Behaviour of priority and emerging pollutants in wetlandsweb.emn.fr/x-dsee/wetpol2013/uploads/book...

ABSTRACTS - WETPOL 2013 - October 13-17, 2013 - Nantes - FRANCE

67

Behaviour of priority and

emerging pollutants in wetlands


68

Treatment of Endocrine Disrupting Chemicals (EDCs) by

Constructed Wetlands – A Case Study in Taiwan (O.2)

Lei Yanga, Yi-Peng Jen

b, Ji-Yin Hsieh

c

aDept. of Marine Environment and Engineering, National Sun Yat-sen University, 70 Lien

Hai Road, Kaohsiung, 80424, TAIWAN ([email protected])

bEnvironmental Protection Administration, Executive Yuan, 83 Chung Hua 1st Road, Taipei,

10042, TAIWAN ([email protected])

cDept. of Environmental Science and Engineering, National Pingtung University of Science

and Technology, 1 Shuefu Road, Neipu, Pingtung, 912, TAIWAN

([email protected])

INTRODUCTION

Alkylphenol polyethoxylates (APEOs) have been widely used for industrial, agricultural

and household applications. The biodegradation metabolites of APEOs, such as nonyphenol

and octylphenol, are more persistent and known to disrupt endocrine function in wildlife and

human. These compounds are also recognized as endocrine disrupting chemicals (EDCs).

The objective of this study is to investigate the distribution and removal efficiencies of EDCs,

including nonylphenol diethoxylates, nonylphenol monoethoxylates, nonylphenol, and

octylphenol, for municipal wastewater treated by constructed wetland systems. In addition,

the method of risk quotient was used to evaluate the potential ecological risk of APEOs to

aquatic organisms in wetlands in this study.

METHODS

The research sites included Daniaopi, Hsinhai Bridge I and Hsinhai Bridge II Constructed

Wetlands, all located along the Dahan River in Taipei, Taiwan. The water samples were

taken seasonally from 18 different sampling sites, located in the three construction wetland

systems, separately. The sketch diagram and sampling sites for each constructed wetland

system were shown in Figure 1. The samples were first extracted by using solid-phase

extraction facility (J. T. Baker Ltd.). The extracted samples were then tested for nonylphenol

diethoxylates, nonylphenol monoethoxylates, nonylphenol, and octylphenol by HPLC

(Waters 2695 Separations Module, Waters Ltd.) and Fluorescence Detector (Waters 2475

Multi λ Fluorescence Detector, Waters Ltd.). In this study, the values of risk quotient (RQ) of

APEOs on aquatic organisms were calculated by using following equation: RQ =

MEC/PNEC, where MEC = measured environmental concentrations of APEOs, and PNEC =

predicted no effect concentrations of APEOs on aquatic organisms, which was developed by

USEPA. RQ<1 can be regarded as accepted risk, while RQ >1 represents unaccepted risk.

RESULTS AND DISCUSSION

The analytical results of water quality in samples taken from 18 sampling sites located in

Daniaopi, Hsinhai Bridge I and Hsinhai Bridge II Constructed Wetlands, separately showed

that the percentages of positive testing result for renonylphenol diethoxylates, nonylphenol

monoethoxylates, nonylphenol, and octylphenol were measured equal to 92%, 85%, 17%,

and 74%, respectively with concentrations ranged from <3.3 to 11192.5, <3.3 to 6069.0, <1.3

to 671.0, and <1.0 to 5581.9 ng/L, respectively. However, the average removal efficiencies

from these three different constructed wetlands for renonylphenol diethoxylates, nonylphenol

monoethoxylates, nonylphenol, and octylphenol were measured equal to 58%, 70%, 43%,

and 55%, respectively. Thus, it was concluded that constructed wetland systems performed


69

well to remove the EDCs of APEOs treating municipal wastewater. Regarding the ecological

assessment, the calculated values of RQ in the constructed wetland systems used in this study

were up to 30 times higher than the compared constructed wetland systems located in

Pingtung County, Taiwan treating salty water type aquacultural wastewater, in which trace

amounts of APEOs under detecting limited values were found.

Fig. 1. Sketch diagrams and sampling sites for Daniaopi, Hsinhai Bridge I and Hsinhai Bridge II

Constructed Wetland systems, located along Dahan River in Taipei, Taiwan.

CONCLUSIONS

It was concluded that the existing concentrations of EDCs of four different types of

APEOs tested in the constructed wetland systems of this study might cause potential

ecological risks to aquatic organisms. Furthermore, the decreasing risk quotient from influent

to effluent indicating the feasibility and capabilities to treat the EDCs of alkylphenolic

compounds by using constructed wetland systems.

REFERENCES Ahel, M., Molnar, E., Ibric, S., and Giger, W. (2000) Estrogenic metabolites of alkylphenol polyethoxylates in

secondary sewage effluents and rivers. Water Science and Technology, 42, pp. 15-22.

Juang, D.F. and Chen, P.C. (2007) Treatment of polluted river water by a new constructed wetland,

Environmental Science and Technology. 4, pp. 481-488.


70

Performance of a cascade constructed wetland treating surfactant

polluted water (O.9)

Jessica Tamiazzo, Simone Breschigliaro, Michela Salvato, Maurizio Borin

DAFNAE – Department of Agronomy, Food, Natural resources, Animals and Environment –

University of Padova, Agripolis Campus, Viale dell’Università 16 – 35020 Legnaro (PD),

Italy ([email protected])

INTRODUCTION

Anionic surfactants are largely used in cleaning sectors, especially in car wash activities

and they are potentially dangerous for the environment, especially for aquatic ecosystem

(Wagener and Schink, 1987).

Urban or industrial treatment systems are able to remove sufficiently the concentration of

anionic and non-ionic surfactants (Gomez et al., 2011). Nevertheless they are expensive, and

constructed wetlands might offer an economic solution (e.g. Mantovi et al., 2003).

In this paper the treatment of anionic surfactants by a pilot constructed wetland designed

to reduce the surface area requirement is presented.

METHODS

The experiment aimed to analyse the performance of an innovative pilot constructed

wetland system (CW), arranged in “cascade”, made of three tanks in series placed at different

elevations: the first tank receives the wastewater from the wastewater reservoir and

discharges by gravity to the second tank that is connected with a third tank and finally to the

outlet. In this way the treatment cells may be installed in vertical, on the side of buildings,

saving significant surface area.

The experiment was conducted in a plant nursery near Padua, Italy. The “cascade” CW

was made of six lines of three tanks each, filled with leca (light expanded clay aggregate),

0.50x0.40x0.29 m in length, width and height respectively, with a tap to discharge the water

(Figure 1). The lines were vegetated with Typhoides arundinacea L. (Moench), Mentha

aquatica L. and Carex divisa Hudson with two replications per species.

Fig. 1. On the left: experimental plant scheme; on the right: transit system of the wastewater in the tank.

To simulate the car washes wastes a synthetic wastewater was created, mixing tap water

and a common carwash cleaning detergent (Autoflash, Kimicar®) to achieve anionic

surfactants concentrations of 10, 50 and 100 mg L-1

that were used in different loading cycles

carried out in October and November 2010 and May-August 2011.


71

Concentrations at outlet were analysed and discharge measured every seven days, as

residence time of CWS. In the final phase, with input concentration of 100 mg L-1

, samples at

outlet were also analysed giving only three days of residence time, increasing the flow rate.

The surfactant analysis was conducted using a Hach-Lange spectrophotometer, DR 2800.


The concentrations measured at the outlet were decisively lower respect to the inlet at all

the inlet concentrations. No statistic differences were obtained among plants that were not

damaged by the surfactant, even at the highest concentration. The highest abatement (98,8%)

was obtained with inlet concentration of 100 mg L-1

and reduced residence time.

The amount of anionic surfactants removed increased increasing the inlet concentration.

With input concentrations of 100 mg L-1

the removal was 17 and 34 g m-2

with 7 and 3 days

of HRT respectively (Figure 2).

0

1

2

3

4

5

6

7

10 50 100 100 AP

Ou

tlet co

ncen

trati

on

(m

g L

-1)

Inlet concentration (mg L-1)

0

5

10

15

20

25

30

35

40

45

10 50 100 100 AP

Rem

ov

al

qu

an

tity

(g

m-2

)

Inlet concentration (mg L-1)

Fig. 2. Anionic surfactants concentrations (mg L-1

) and removal (g m-2

) at outlet in relation to inlet.

CONCLUSIONS

The pilot “cascade” system well performed in abating surfactants pollution even at very

high concentrations and represents an interesting perspective to implement wetland treatment

where limited surface is available. The studied plants had similar efficiency and were not

damaged by the high concentrations of surfactant applied.

ACKNOWLEDGEMENTS

Research carried out with the financial support of MIPAF OIGA 2009 Project

“Reproduction, cultivation and evaluation of vegetal species for environmental purposes”.

REFERENCES Gomez, V., Ferreres, L., and Pocurull, F. (2011) Determination of non-ionic and anionic surfactants in

environmental water matrices. Talanta 84:859-866.

Mantovi, P., Marmiroli, M., Maestri, E., Tagliavini, S., Piccinini, S., and Marmiroli, N.(2003) Application of a

horizontal subsurface flow constructed wetland on treatment of dairy parlor wastewater. Bioresource

Technology 88: 85–94.

Wagener, S., and Schink, B. (1987) Anaerobic degradation of nonionic and anionic surfactants in

enrichment cultures and fixed-bed reactors. Water Research 21(5):615–622.


72

Perchloroethene removal in a plant root mat filter and horizontal

subsurface flow constructed wetland treating a sulfate rich

contaminated groundwater (O.21)

Zhongbing Chen, Peter Kuschk

Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research

– UFZ, Permoserstrasse 15, 04318 Leipzig, Germany ([email protected])

INTRODUCTION

Because of improper uses and storage, PCE has been recognized as being among the most

ubiquitous groundwater contaminants. PCE and its’ metabolites trichloroethene (TCE),

dichloroethenes (DCEs) and vinyl chloride (VC), are known to be toxic to humans. VC is

even known as a human carcinogen, and is an USEPA priority pollutant with a maximum

contaminant level (MCL) of 2 µg L-1 in drinking water. Anaerobic conditions are necessary

for the first step of reductive dechlorination of PCE to TCE, which can be followed by

reductive dechlorination or oxidation of TCE, dichloroethenes (1,1-DCE, 1,2-trans-DCE, 1,2-

cis-DCE), VC and ethene under anaerobic and/or aerobic conditions (Bradley, 2003; Mattes

et al., 2010). However, the use of CWs for treating chlorinated hydrocarbons contaminated

groundwater is scarce to date (Braeckevelt et al., 2011; Pardue et al., 1999; Kadlec et al.,

2012).

Floating plant root mat is a variant of CWs, in which the plants are no longer rooted in a

soil but grow on floating rafts, or floating by the self-buoyancy of their dense interwoven

roots and rhizomes that form a mat (Headley & Tanner, 2011; Van de Moortel et al., 2010).

When the water level is lowered to such an extent that the mat touches the root proof bottom

of the pond or channel, and the hydraulic flow is forced directly through the root mat, this

system functions as a plant root mat filter (PRMF). The floating plant root mats and the non-

floating PRMFs are not yet broadly applied technologies (Chen et al., 2012; Tanner &

Headley, 2011; Van de Moortel et al., 2010). Especially, no information on the treatment of

water contaminated with chlorinated ethenes by PRMFs is available.

The objective of this study was to compare the treatment of sulfate rich groundwater

contaminated with PCE in two pilot-scale CWs (a horizontal subsurface flow (HSSF)-CW

and a PRMF).

METHODS

The HSSF CW was established in March 2003 and the PRMF in March 2010 in Bitterfeld,

Germany. Each system consisted of a container with 6 m length, 1 m width and 0.6 m height.

The HSSF CW was filled with the local aquifer material to a height of 0.5 m and planted with

common reed (Phragmites australis). More details about this HSSF CW are described

elsewhere (Braeckevelt et al., 2011). The PRMF was set with 3 years old well developed

plant root mats of a height of about 30 cm of common reed with densely interwoven roots.

Both systems were continuously supplied with contaminated groundwater with a flow rate of

5.0 L/h. The inflow concentration of PCE is about 2 mg L-1 and sulfate concentration is

around 850 mg L-1.


PCE was removed completely after a flow path of 4 m during the recorded period in the

HSSF CW. However, in the PRMF a similar PCE removal performance was only reached

during summer period. This could be due to the temperature effect on the microbial activity,

mailto:[email protected]


73

as the soil free PRMF seems to be more sensitive than the soil based HSSF CW; so, in the

PRMF the temperature was during summer about 1°C higher and during winter about 1 °C

lower than in the HSSF CW). On the other hand, the plant activity was stable during the

summer period (represented by water loss); it can be assumed that during this period plants

release more organic carbon than during the colder seasons which is needed for the anaerobic

dechlorination process. Significant differences of the PCE load along the flow path was found

between the HSSF CW and the PRMF ( P=0.002), which means lower residual PCE load was

found in the HSSF CW in comparison to the PRMF. The HSSF CW showed robust PCE

removal capacity, as all PCE was removed after 0.5 m from the inlet in the HSSF CW. The

difference of PCE concentration in three depths in the HSSF CW was only found at 0.5 m

between the 30 cm with 50 cm and 40 cm with 50 cm (P=0.009 and 0.041, respectively).

CONCLUSIONS

The PRMF showed lower removal efficiency for PCE than the HSSF CW. Nevertheless,

during the summer period PCE was also completely removed like in the HSSF CW. In

comparison to the HSSF CW, not all dechlorination products could be detected, especially

VC and ethene, which are preferably metabolized by microorganisms via an aerobic pathway.

The PRMF seems to be more suitable for the removal of contaminants which need oxic

condition like low chlorinated hydrocarbons as VC for their microbial degradation, while

HSSF CW provide better conditions for microbial anaerobic processes like the dechlorination

of highly chlorinated hydrocarbons as PCE prevail.

REFERENCES Bradley, P.M. 2003. History and Ecology of Chloroethene Biodegradation: A Review. Bioremediat. J., 7(2), 81-

109.

Braeckevelt, M., Seeger, E.M., Paschke, H., Kuschk, P., Kaestner, M. (2011). Adaptation of a Constructed

Wetland to Simultaneous Treatment of Monochlorobenzene and Perchloroethene. Int. J. Phytoremediation.,

13(10), 998-1013.

Chen, Z., Kuschk, P., Reiche, N., Borsdorf, H., Kästner, M., Köser, H. 2012. Comparative evaluation of pilot

scale horizontal subsurface-flow constructed wetlands and plant root mats for treating groundwater

contaminated with benzene and MTBE. J. Hazard. Mater., 209–210, 510-515.

Headley, T.R., Tanner, C.C. 2011. Constructed Wetlands with Floating Emergent Macrophytes: an innovative

stormwater treatment technology. Crit. Rev. Environ. Sci. Technol., In press.

Kadlec, R.H., Martin, D.C., Tsao, D. 2012. Constructed marshes for control of chlorinated ethenes: An 11-year

study. Ecol.Eng., 46(0), 11-23.

Mattes, T.E., Alexander, A.K., Coleman, N.V. 2010. Aerobic biodegradation of the chloroethenes: pathways,

enzymes, ecology, and evolution. FEMS Microbiology Reviews, 34(4), 445-475.

Pardue, J.H., Kassenga, G., Shin, W.S. 1999. Design approaches for chlorinated VOC treatment wetland.

Wetlands and Remediation: An International Conference, Salt Lake City, Utah. Batelle Press, Columbus(OH),

USA. pp. 301–308.

Tanner, C.C., Headley, T.R. 2011. Components of floating emergent macrophyte treatment wetlands influencing

removal of stormwater pollutants. Eco. Eng., 37(3), 474-486.

Van de Moortel, A., Meers, E., De Pauw, N., Tack, F. 2010. Effects of Vegetation, Season and Temperature on

the Removal of Pollutants in Experimental Floating Treatment Wetlands. Water Air Soil Pollut., 212(1), 281-

297.


74

Transport and biodegradation of chloroacetanilide herbicides in

lab-scale wetlands (O.23)

G. Imfelda, E. Maillard

a, O.F. Elsayed

a, I. Nijenhuis

b, M. Millet

c

a Laboratory of Surface Hydrology and Geochemistry of Strasbourg (LHyGeS), UMR7517

University of Strasbourg - CNRS, France

b Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research

(UFZ), Leipzig, Germany

c Atmospheric Physical Chemistry Department (LMSPC), University of Strasbourg, UMR

7515 CNRS, France

INTRODUCTION

Chloroacetanilide herbicides, such as metolachlor, alachlor and acetochlor, are used for

control of annual grasses and broad-leaved weeds on a variety of crops including maize,

sugar beet and sunflower. The extensive use of chloroacetanilide herbicides is reflected in

their frequent detection in ground and surface waters. Wetland systems can intercept upward

flow of pesticide-contaminated water from shallow aquifers during groundwater discharge.

Knowledge on the transfer and biodegradation of chloroacetanilide herbicide in wetlands in

relation with biogeochemical conditions is very scarce. Compound-specific stable isotope

analysis (CSIA) is a promising approach for the assessment of contaminant degradation in the

environment, but has not yet been reported for the evaluation of pesticide biodegradation in

wetlands.

Here, we examined the transfer and biodegradation of metolachlor, alachlor and acetochlor

in lab-scale wetlands using a comprehensive approach that combine hydrochemical, chiral

and compound-specific isotope analyses. The lab-scale wetlands were designed to investigate

the influence of upward discharge of pesticide-contaminated groundwater into wetland

systems.

METHODS

The experimental design consisted of 4 wetland columns (diameter: 15 cm, height: 65 cm).

3 columns were separately and continuously supplied with 1.8 µM (~500 µg L-1

, i.e. runoff

concentration after herbicide application) of Rac-metolachlor, acetochlor and alachlor spiked

in fresh runoff water from a vegetated ditch collecting runoff-associated chloroacetanilides

from agricultural land (background herbicide concentration < 2 µg L-1

). A fourth column

(control) was supplied with runoff water only. The wetlands were filled with gravel and sand

and planted with Phragmites australis (Cav.), kept at 20 °C ± 0.5 °C, and exposed to LED

lamp light for 8 h d-1

. The nominal residence time was 9.3 days (bromide tracer experiment).

The experiment was carried out over 202 days. The continuous injection of

chloroacetanilides in the wetlands was preceded by an inoculation period of 104 days during

which runoff water was supplied without herbicides. Porewater samples were collected at the

inlet and outlet of each column, and from sampling ports mounted at 15, 25, 35, 45 and 55 cm

from the inlet point. The sampling campaigns were carried out biweekly at 0, 14, 28, 42, 56,

70, 84 and 98 days after the chloroacetanilide injection started.

Dissolved organic carbon, major and trace ions, total phosphorous, total sulfur and metals

were quantified by FR EN ISO standards and laboratory procedures. Chloroacetanilide

herbicides in water samples were extracted using a solid-phase extraction (SPE) procedure

and quantified with a GC-MS equipped with a chiral column. The carbon isotope


75

composition of chloroacetanilides was analysed using a GC-C-IRMS system consisting of a

gas chromatograph coupled via a GC/C III interface to an isotope ratio mass spectrometer.


A spatial gradient of oxygen concentrations was observed in the four lab-scale wetlands

with oxic conditions (212 ± 24 µM) prevailing at the bottom of the wetlands between 15-25

cm, and anoxic conditions between 45-55 cm from inlet points. Nitrate depletion observed in

the four wetlands suggests the occurrence of nitrate reducing conditions in anoxic zones

towards wetlands outlets. The high removal between day 0 and 28 was mainly attributed to

sorption. Removal of acetochlor and alachlor loads from inlets to outlets from day 28 to day

98 averaged 56 ± 6% and 53 ± 11%, respectively, whereas metolachlor was more persistent

(average mass removal of 23 ± 5%) (Fig. 1). A bulkier alkoxyethyl side chain leading to

greater steric hindrance around the carbon chlorine bond and lower degradation rates may

explain the greater persistence of metolachlor.

Fig. 1. Temporal change of metolachlor, alachlor and acetochlor mass removal in the wetlands.

Biodegradation occurred mainly in anoxic zones as evidenced by both concentration

analysis and CSIA. Enrichment factors could not be calculated for metolachlor because

changes in the isotopic composition were ≤ 0.8‰. Carbon isotope fractionation indicated in

situ biodegradation of alachlor (Ɛbulk = -2.0 ± 0.3) and acetochlor (Ɛbulk = -3.4 ± 0.5). Similar

enrichment factors over time suggest that the same degradation pathways prevailed in the

wetland throughout the investigation period. An orbitrap-based MS analysis revealed the

occurrence of 3 to 4 degradation products in each wetland. The enantiomeric separation of

metolachlor revealed EF(S) < 0.5, which suggests enantioselective degradation at the outlet.

CONCLUSIONS

Based on a multiple-method approach, the results underscore the linkage between the

changes of hydrochemical conditions and degradation of chloroacetanilide herbicides in

wetland systems. Our results indicate moderate mass removal for acetochlor and alachlor and

lower removal for metolachlor in wetland systems. Enantioselective degradations could affect

the fate of metolachlor in wetland environments, and emphasise the role of chirality in

pesticide degradation. This study is also a first step towards the application of CSIA to

evaluate the fate of chloroacetanilide herbicides in wetlands and other complex environments.

ACKNOWLEDGEMENTS

This research has been funded by the European Union under the 7th Framework

Programme (Marie Curie ITN CSI:ENVIRONMENT, contract number PITN-GA-2010-

264329.) and the PhytoRET project (C.21) of the European INTERREG IV program Upper

Rhine.


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Response of a free-water surface constructed wetland after a

Cr(VI) accidental dump (O.39)

Maine, M.A.1,2

, Sánchez, G.C.1, Mufarrege M.M.

2, Hadad, H.R.

2, Di Luca,

G.A.2, Caffaratti, S.E.

1, Pedro, M.C.

1

1Química Analítica, Facultad de Ingeniería Química, Universidad Nacional del Litoral.

Santiago del Estero 2829 (3000) Santa Fe, Argentina ([email protected]) 2Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina.

INTRODUCTION Constructed wetlands (CW) are often designed as secondary or tertiary treatments for

industrial wastewater (Kadlec and Wallace, 2009). CWs efficiently decrease mean

concentrations and variability concentrations of contaminants in water. This regulation

capacity implies an important advantage: if the primary treatment failed and there was an

accidental load of high concentrations of contaminants, the CW would retain them. A free-

water surface wetland was constructed and planted with Typha domingensis (cattail) at a

metallurgic industry. The effluent to be treated is composed of industrial wastewater and

sewage (both had previously received a primary treatment). The primary treatment of the

industrial effluent consists of the reduction of Cr(VI) to Cr (III) and the subsequent

oxihydroxides precipitation. This wetland normally receives effluents with Cr concentrations

of 0.10-3.5 mg l-1

. The aim of this work was to evaluate the response of the wetland system

faced with an accidental dump of Cr(VI).

METHODS

A metallurgical effluent with a concentration of 200 mg l-1

Cr(VI) was poured in the

wetland for 8 hs. Then, the wetland was closed for 30 days, avoiding the effluent outflow.

Cr(VI), total Cr, pH and conductivity were measured in the effluent in the inlet and outlet

area. Cr was also determined in T. domingensis (root and leaf), sediment and plant detritus at

the beginning and 30 days after the dumping. Cr(VI) concentration was determined

colorimetrically. Total Cr concentration was determined in water, sediment and macrophytes

after acid digestion by atomic absorption spectrophotometry.


The concentration of Cr(VI) and total Cr in water decreased significantly in the outlet

effluent (Fig. 1). No significant differences were found between the concentration of total Cr

and Cr(VI) in water over time. Cr(VI) can be reduced by organic matter, Fe(II), dissolved

sulfides, and humic compounds with sulfhidryl groups (Kadlec et al., 2000). In this case,

organic matter probably caused the reduction of Cr(VI) to Cr(III), which immediately

precipitated as oxihydroxides. After the dump, Cr concentration in sediment was significantly

greater in the inlet than in the outlet area, indicating retention by sediment (Table 1). T.

domingensis tolerated the treatment in the outlet area while it died in the inlet area. A layer of

plant detritus covered the sediment in the inlet area. Plant detritus showed higher Cr

concentration than sediments (Table 2). Cr concentration increased significantly in root

tissues of the inlet area, reaching values higher than those reported in literature (Dotro et al.,

2009; Maine et al., 2007). Cr concentration in leaves was significantly lower than that found

in roots, indicating low translocation. As Cr concentration in water decreased after 30 days,

the wetland was emptied, plant detritus containing high Cr concentrations was removed and

new specimens of T. domingensis were planted in the inlet area.


77

Fig 1. Cr(VI) and total Cr concentrations (mg l-1 ) in water at the wetland outlet

Table 1. Total Cr concentrations (mg g

-1) in sediment at the wetland inlet and outlet

Sediment Inlet Outlet

Initial 0.065 0.016

After 30 days 0.916 0.070

Table 2. Total Cr concentrations (mg g

-1) at the wetland inlet and outlet

Inlet Outlet

Initial conditions Leaf Root Leaf Root

T. domingensis 0.024 0.535 0.011 0.068

After 30 days

T. domingensis 0.677 12.44 0.042 0.715

Plant detritus 11.62 1.98

CONCLUSIONS

Cr(VI) was efficiently removed from water after 30 days. Accumulation of Cr in

sediment, plant detritus and root plants were the pathways responsible for the

disappearance of Cr from water.

Plant detritus with high Cr concentration was easily removed from the wetland.

T. domingensis accumulated high Cr concentrations and was affected in the inlet

area while it did not show phytotoxic symptoms in the outlet area.

90 days after the dump, the wetland restarted its normal operation, demonstrating

the robustness of this treatment system.

ACKNOWLEDGEMENTS

The authors thank Consejo Nacional de Investigaciones Científicas y Técnicas

(CONICET), Universidad Nacional del Litoral (UNL)-CAI+D Project and Agencia de

Promoción Científica y Tecnológica for providing funds for this work.

REFERENCES Dotro G., Palazolo P. and Larsen D. (2009) Chromium fate in constructed wetlands treating tannery

wastewaters. Wat. Environ. Res., 81(6):617-625.

Kadlec, R.H., Knight, R.L., Vymazal, J., Brix, H., Cooper, P. and Haberl, R. (2000) Constructed Wetlands for

Pollution Control: Processes, Performance, Design and Operation. IWA Publishing.

Kadlec, R.H. and Wallace, S.D. (2009) Treatment Wetlands, CRC Press, Boca Raton, Florida. 893p.

Maine, M.A., Suñé, N., Hadad, H.R., Sánchez, G. and Bonetto, C. (2007) Removal effciency of a constructed

wetland for wastewater treatment according to vegetation dominance. Chemosphere. 68:1105-1113.

0

20

40

60

80

100

120

140

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30

Days

mg

l-1 C

r

Total Cr Cr(VI)


78

Use of rewetted fen peatlands for the degradation of emerging

pollutants (O.43)

Sebastian Maassen, Dagmar Balla, Ralf Dannowski

Leibniz Centre for Agricultural Landscape Research (ZALF), Institute of Landscape

Hydrology, Eberswalder Strasse 84, Müncheberg, 15374, GERMANY ([email protected],

[email protected], [email protected])

INTRODUCTION

In a joint research project (ELaN) started in 2011, we are analyzing degraded fen soils of

the Randow-Welse lowlands in the sparsely populated rural Uckermark region in

northeastern Germany with reference to their suitability for biomass production (short

rotation coppice, reeds). In terms of sustainability, peat mineralization processes have to be

reduced by high water levels. Because of the negative water budget during the vegetation

period, supplemental water pumped from the channel system is required to be given upon the

surface for rewetting (Dannowski & Balla 2004). Rewetted fen peatlands could be integrated

into water protection purposes by the additional purification of treated waste water. We

hypothesize that with the application of treated waste water on rewetted peat sites the

potential for the anaerobic decay of emerging pollutants increases due to both, high organic

matter/DOC content in the peat as well as a prolonged residence time during the groundwater

passage as shown in Fig. 1.

Fig. 1. Schematic of the use of rewetted fen sites for energy plant production and as an additional cleaning

stage for waste water treatment.

The feasibility of this idea strongly depends on the proof of harmlessness for the

groundwater quality. In order to protect groundwater bodies from hazardous substances, all

regulations allow the utilization of treated waste water only in limited boundaries. Hence, our

investigations are focused on the proof of the environmental compatibility with respect to

groundwater protection. The study site had previously been rewetted with supplemental water

in an earlier research campaign from 1996 to 2002. From 2002 to 2011, the site was

abandoned and intensified peat mineralization took place. Our intention is also to deal with

the site’s abiotic aspects after intermediately losing the rewetting status.

METHODS

The Biesenbrow site (8 ha) located in the Randow-Welse valley (Uckermark, state of

Brandenburg) consists of fen peat up to 120 cm in thickness which in former time was

drained and sub-irrigated under intensive grassland use. During the rewetting period 1996-

2002, an abiotic monitoring of soil parameters as well as ground- and surface water chemistry

was performed (Balla et al., 2004). Before the re-start of rewetting in 2011, a topographical

survey and groundwater chemistry analysis were performed at the site. Groundwater

monitoring wells in three depths (2, 4, 6 m) were installed to screen the groundwater quality

(a) common practice for the discharge

of treated waste water (as quickly as

possible into the running water system)

(b) hypothesized bypass flux using the

anaerobic peat layer and long travel

times (t > months or years) passing the

groundwater body into the receiving

surface waters


79

with regard to emerging pollutants, heavy metals, cations and anions. The residence time in

groundwater will be modeled by the finite element Model FEFLOW (DHI-WASY). To

calibrate the model, thermodynamic parameters at the channel bottom are measured and the

water and mass flux from the rewetted site into the surrounding channels is determined

(Maassen and Balla, 2010).


In comparison of the original geodetic survey before rewetting in 1995, in 2011 the area

has lost 6.6 cm in height in average of all measurement points, with minimum of 0 and

maximum of 18 cm. The elevation differences are heterogeneously distributed. Related to the

16 years without cultivation (no plowing, no fertilizer, no biomass removal), the loss in

elevation is approximately 0.4 cm per year. The water chemistry of the monitored

groundwater wells showed a significant increase of the sulfate concentration (SO4), as well as

a decrease of soluble phosphorus (SRP) and dissolved organic carbon (DOC). The chloride

concentration (Cl) was nearly constant. The obvious rise of sulfate is most likely attributed to

peat mineralization and the release of soil bound sulfur, whereas the trends of the other

parameters might be a result of regional mineralized groundwater upwelling through the peat

layer beyond the irrigation period. After nearly two years of irrigation with addition of treated

wastewater (6 months during the growing seasons of 2011 and 2012), approximately

4,000 m3 of treated wastewater mixed with 30,000 m

3 of channel water was applied at an area

of 4 ha. There were no adverse effects on groundwater quality detectable. Some groups of

substances show "hot spots" in the concentrations in treated wastewater (e.g. pharmaceuticals

Diclofenac and Carbamazepine, flame retardant tris-(chlorisopropyl)-phosphate).

CONCLUSIONS

In degraded fens rewetted with admixture of treated wastewater, added value can be

achieved by biomass production and an extra purification of the wastewater, particularly in

rural areas without the intention of the immediate use of the groundwater resource. Therefore,

the inclusion of degraded fens into future infrastructures for the disposal and usage of

wastewater could be a promising alternative for the conservation of surface water systems.

ACKNOWLEDGEMENTS

The ELaN project (www.elan-bb.de) is funded by the Federal Ministry of Education and

Research within the funding activity "Sustainable Land Management".

REFERENCES Balla, D., Velty, S. and Dannowski R. (2004) Wirkung einer Wiedervernässungsmaßnahme auf das Grund- und

Oberflächenwasser – Pilotanlage Biesenbrow. Archiv für Naturschutz und Landschaftsforschung 43:41-58.

Dannowski, R. and Balla, D. (2004) Wasserhaushalt und geohydrologische Situation einer vernässten

Niedermoorfläche mit Schilfanbau in Nordost-Brandenburg. Archiv für Naturschutz und Landschaftsforschung

43:27-40.

Maassen, S. and Balla, D. (2010) Impact of hydrodynamics (ex- and infiltration) on the microbially controlled

phosphorus mobility in running water sediments of a cultivated northeast German wetland. Ecol. Eng. 36

(9):1146-1155.


80

Pesticide transport, partitioning and distribution in a stormwater

wetland collecting runoff from a vineyard catchment (O.53)

E. Maillarda and G. Imfeld

a

aLaboratory of Hydrology and Geochemistry of Strasbourg (LHyGeS), University of Strasbourg/ENGEES,

CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, FRANCE ([email protected]; [email protected])

INTRODUCTION

Wetlands are biogeochemically active zones that may intercept pesticide-contaminated

runoff and contribute to pesticide attenuation before they reach aquatic ecosystems (Imfeld et

al, 2009). The transport and fate of pesticides in wetlands is mainly governed by their

partitioning between the solid and aqueous phases, and their distribution between the

different compartments (i.e. bed sediments, vegetation, water and organisms). Although

several studies have focused on pesticides in wetlands (Maillard et al, 2012), the distribution

of runoff-associated pesticides between wetland compartments has never been quantified.

There is a need to identify the major pools of pesticides in wetland systems and quantify their

change over time to better understand wetland functioning with respect to pesticide

metabolism. In this study, we used a mass-balance approach to quantify, throughout an entire

season, runoff-associated herbicides and fungicides and their distribution among the different

compartments of a stormwater wetland collecting pesticide runoff.

MATERIAL AND METHODS

The studied stormwater wetland (Rouffach, France) is located at the outlet of a 42 ha

vineyard catchment. The wetland has a surface area of 319 m2 (including a forebay and a

gravel filter), a residence time of about 10 h, and is naturally planted with common reeds. 11

fungicides, 1 herbicide and 1 degradation product were monitored from March to September

2011. Runoff discharges were continuously measured at the inlet and outlet of the wetland

and weekly composite water samples were collected. Pesticides were quantified in suspended

solids (> 0.7 µm), and in < 0.7 µm and < 0.22 µm filtrate water. A mass balance was

established to quantify monthly the pesticide amount in the vegetation and

macroinvertebrates biomasses, as well as in the wetland water and sediments.


During the investigation period, 1944 m3 of runoff water entered the stormwater wetland,

leading to a total input of 33.6 tons of suspended solids (> 0.7 µm).

Fig. 1. Relative loads of pesticides associated with suspended solids (> 0.7 µm) and in the

aqueous phase (< 0.7 µm) at the inlet (A) and the outlet (B) of the studied stormwater wetland.

Rat

io L

oad

/ L

oad

to

t [%

] Ratio Load /

Load tot

[%]


81

In the same time, 58.8 g of dissolved pesticides and 3.0 g of particle-laden pesticides

entered the wetland over the season. Outlet pesticide loads were 2.3 g and 56.6 mg,

respectively in the dissolved and in the particulate phase. Pesticide partitioning differed

according to molecule properties (Fig.1). The removal efficiency varied over time with

respect to hydrological and biogeochemical conditions in the wetland, and was 96.1% for

dissolved pesticides and 98.1% for particle-associated pesticides.

Glyphosate, AMPA and dithiocarbamates were molecules with the largest loadings in the

wetland (Fig.2). The highest pesticide loads (26.3 g) were detected in the wetland fine bed

sediments (< 250 um) and in the SS (13.3 g) trapped by the gravel filter, especially at the end

of the season, in September. This highlights the large pesticide trapping efficiency of wetland

sediments and wetland-intrinsic biotransformation processes. In contrast, coarser sediments

(> 1mm), wetland vegetation and macroinvertebrates biomasses bore less pesticide amounts.

Pesticide loads bound to the vegetation, and in particular to the roots, decreased over time,

suggesting that the root zone was mainly involved in pesticide transformation/degradation.

CONCLUSIONS

This study shows that wetlands are efficient for trapping both dissolved and sorbed

pesticides. This is the first time that a detailed quantification of pesticide pools within a

wetland is provided. This enabled to identify which compartments mainly contribute to

pesticide transport, accumulation (i.e. bed sediments) or transformation (i.e. roots

compartment). Pesticide accumulation in sediments raises the issue of pesticide

remobilization and their management after dredging operations. We anticipate our results to

be a starting point for the quantitative analysis of pesticide partitioning among wetland

compartments, with further implications for the ecotoxicological risks associated with

pesticide runoff.

ACKNOWLEDGEMENTS This research has been funded by the PhytoRET project (C.21) of the European INTERREG IV program

Upper Rhine. Elodie Maillard was supported by a fellowship of U.E. and the Alsace region.

REFERENCES Imfeld G, Braeckevelt M, Kuschk P and Richnow HH (2009) Monitoring and assessing processes of organic

chemicals removal in constructed wetlands. Chemosphere 74, pp. 349-362

Maillard E, Payraudeau S, Ortiz F and Imfeld G, (2012) Removal of dissolved pesticide mixtures by a

stormwater wetland receiving runoff from a vineyard catchment: an inter annual comparison. International

Journal of Environmental Analytical Chemistry, Volume 92, Issue 8, pp. 979-994.

Fig. 2. Distribution of the pesticide mixture between the different compartments of the wetland.

Ratio Load /

Load tot

[%]

Wetland compartments

203 Total loads [mg] 461 505 26258 121

909 33 0.5 200 13388 1920

2092 75


82

Removal of emerging organic contaminants in hybrid constructed

wetlands for the treatment of wastewater of small communities of

warm climate regions (O.54)

Cristina Ávilaa, Carlos Aragón

b, Isabel Martín

b, Juan J. Salas

b, Josep M.

Bayonac, Joan García

a

aGEMMA-Group of Environmental Engineering and Microbiology, Department of

Hydraulic, Maritime and Environmental Engineering, Universitat Politècnica de Catalunya-

BarcelonaTech, c/Jordi Girona, 1-3, Building D1, Barcelona, 08034, SPAIN

([email protected], [email protected])

bFoundation Centre for New Water Technologies (CENTA). Autovía Sevilla-Huelva (A-49),

km. 28. Carrión de los Céspedes, Seville, 41820, SPAIN ([email protected],

[email protected], [email protected])

cDepartment of Environmental Chemistry, IDAEA-CSIC, c/Jordi Girona, 18-26, Barcelona,

08034, SPAIN ([email protected])

INTRODUCTION

Constructed wetlands (CWs) constitute a good alternative for wastewater treatment of

small communities worldwide. A comprehensive approach aiming at combining different

types of CWs proved to be a highly efficient ecotechnology for an integrated sanitation of

small communities in warm climates, holding very low O&M requirements (Ávila et al.,

2013). It produced a good final effluent for its reuse after the treatment of combined sewer

effluent, even at stormy periods and first-flush events. However, the occurrence of emerging

organic contaminants (EOCs) in poorly treated wastewater and eventually in other

watercourses constitutes nowadays an increasing concern worldwide due to their possible

toxicological effects to the environment and living organisms. The application of reclaimed

water could pose unknown undesirable effects to the environment and thus the occurrence

and behavior of EOCs in this type of treatment systems should be further studied.

The scope of this study was to evaluate the efficiency of a full-scale hybrid CW system

located in Seville (southern Spain) on the removal of several EOCs (i.e. ibuprofen –IB-,

diclofenac –DCF-, acetaminophen –ACE-, carbamazepine –CBZ-, ethinyl estradiol –EE2-,

tonalide –AHTN-, oxybenzone –OXY-, triclosan –TCS-, bisphenol A –BPA-) from a

combined sewer effluent.

METHODS

The hybrid treatment system was part of a larger pilot-scale treatment plant that received

the wastewater from 2500 P.E. from the municipality of Carrión de los Céspedes (Seville,

Spain) together with the runoff collected in a combined sewer system. The treatment line

consisted of an imhoff tank followed by a 317 m2 vertical subsurface flow CW (VF), a 229

m2 horizontal subsurface flow CW (HF) and a 240 m

2 free water surface CW (FWS) in

series. They were all planted with Phragmites australis and received an average flow of 14

m3 d

-1. The VF received an average organic loading rate of about 9 g BOD5 m

-2 d

-1 and an

average hydraulic loading rate of 44 mm d-1

. The final effluent was collected in a 20 m3 open-

air water tank working as a raft for irrigation.

Effluent 24-h composite samples of the different treatment units were grabbed once a

week (n = 8) from May to June 2011. They were transported to the laboratory in 250 mL

amber glass bottles and kept refrigerated at 4ºC until analysis (sample holding time < 1 day).

Samples were analysed for EOCs as described elsewhere (Matamoros and Bayona, 2006).


83


Mean values and standard deviations of wastewater quality parameters along the treatment

line are shown in Table 1. The hybrid CW system was very efficient on their removal.

Results for EOCs (Fig. 1) showed that they could be categorized as (i) efficiently removed

compounds with removal higher than 85% (IB, ACE, AHTN, BPA) and (ii) moderately

removed compounds with removal efficiencies between 50% and 85% (DCF, CBZ, TCS).

EE2 and OXY were <LOD in every sampling point throughout the study. The removal of

ACE took place completely in the VF wetland. Table 1. Wastewater physico-chemical characteristics at the effluent of the different treatment units along

the treatment line. Mean values and standard deviations are shown.

Influent Imhoff tank VF HF FWS

T (°C) 23.8 ± 1.7 24.0 ± 1.7 22.8 ± 1.6 22.2 ± 1.7 19.9 ± 1.7

DO (mg L-1

) 0.2 ± 0.0 0.2 ± 0.0 2.0 ± 1.7 4.2 ± 0.4 2.7 ± 0.3

Eh (mV) -138 ± 8 -198 ± 31 -124 ± 9 -61 ± 44 -71 ± 61

TSS (mg L-1

) 212 ± 59 114 ± 33 9 ± 4 15 ± 5 6 ± 2

BOD5 (mg L-1

) 320 ± 57 125 ± 7 11 ± 8 7 ± 2 6 ± 2

TN (mg L-1

) 40.1 ± 8.8 38.5 ± 6.1 13.3 ± 3.6 3.6 ± 1.4 2.4 ± 0.6

TP (mg L-1

) 5.9 ± 1.2 5.9 ± 1.6 5.3 ± 1.8 4.2 ± 2.0 3.1 ± 0.4

Ibup

rofe

n

Diclofe

nac

Ace

tam

inop

hen

Car

bam

azep

ine

EE2

Tonalide

Oxy

benz

one

Bisph

enol A

Triclosa

n

Co

nce

ntr

atio

n (

g L

-1)

0

1

2

3

4

5

6

14

16

18

20

22 Influent

Imhoff

VF

HF

FWS

Ibup

rofe

n

Diclofe

nac

Car

bam

azep

ine

Tonalide

Bisph

enol A

Triclosa

n

Re

mo

va

l e

ffic

ien

cy (

%)

0

20

40

60

80

100 VF

HF

FWS

Figure 1. (a) Concentration of the different EOCs along the treatment line; (b) Accumulated removal

efficiencies of selected EOCs at the different units of the hybrid CW system.

The experimental system appears as an integrated approach capable of accomplishing a

good removal of EOCs. This reinforces the idea of hybrid CWs as very robust systems for

wastewater treatment and reuse in small communities. Since monitoring was carried out in

summer season, the performance in winter time should be further evaluated.

ACKNOWLEDGEMENTS

This research has been funded by the Spanish Ministry of Environment (MMARM)

through the Project No. 085/RN08/03.2. Ms. Cristina Avila kindly acknowledges a

predoctoral fellowship from the Universitat Politècnica de Catalunya. BarcelonaTech.

REFERENCES Ávila, C., Salas, J.J., Martín, I., Aragón, C. and García, J. (2013) Integrated treatment of combined sewer

wastewater and stormwater in a hybrid constructed wetland in southern Spain and its further reuse. Ecological

Engineering 50:13-20.

Matamoros V. and Bayona J.M. (2006) Elimination of pharmaceuticals and personal care products in subsurface

flow constructed wetlands. Environmental Science and Technology 40:5811-5816.

(a) (b)


84

Temporal and Spatial Dynamics of Organochlorine Pesticides in

the Suspended Particulate Matter from Lake Chaohu (O.96)

Fu-Liu Xu, Qing-Mei Wang, Wei He, Ning Qin, Xiang-Zhen Kong,

MOE Laboratory for Earth Surface Process, College of Urban & Environmental Sciences,

Peking University, Beijing 100871, China ([email protected])

INTRODUCTION

China is one of the countries with the largest amount production and usage of

organochlorine pesticides (OCPs) in the world. Some OCPs such as DDTs have been banned

to use in China since 1983; however, they are still detected in various environmental and

biological media (Tao et al., 2008). In the present study, the residual level, temporal-spatial

variation, composition, potential sources and ecological risks of OCPs in the SPM from Lake

Chaohu, the fifth largest lake in China were studied.

METHODS

The SPM samples were collected monthly through the filtration of water samples from

four sites located in the eastern, central and western area of Lake Chaohu during May 2010 to

April 2011. The Microwave-assisted extraction method and a silica gel-neutral alumina

mixed column were used to extract and purify the SPM samples. OCPs in the SPM samples

were analysed by GC-MS.


Residues of OCPs in the SPM

Seventeen types of OCPs were detected in the SPM samples. The annual average

concentration of total OCPs in the SPM was 172.68 ± 434.88 ng/g. The residual level of

DDTs was the highest (138.76 ± 407.27 ng/g), accounting for 80.4% of the total OCPs,

followed by HCHs (15.08 ± 10.30 ng/g) and HCB (9.74 ± 15.77 ng/g), accounting for 8.7%

and 5.6% of the total OCPs, respectively.

The temporal-spatial variations of OCPs in the SPM

The spatial distribution of OCPs in the SPM followed such order as eastern lake (46.07

ng/g) > western lake (39.38 ng/g) > central lake (30.88 ng/g). The concentration of OCPs

remained steady from May to July and reached a maximum value in August, then fell rapidly

in September and continued to decrease from September to November. Seasonal trends in the

HCH and DDT contents were different. Specifically, the concentration of HCHs increased

slightly from spring to autumn, while the maximum concentration of DDTs was observed in

the summer, which was higher that of the other two seasons (Fig.1).

Composition of OCPs in the SPM

HCHs and DDTs were the two dominant OCPs. DDTs were the most dominant OCPs in

the spring and summer, and its proportion reached a maximum value in the summer (87.92%)

and decreased to a minimum in the fall (33.38%). The dominant OCPs in the fall was HCHs,

and its proportions in the spring, summer and fall accounted for 8.95%, 4.08% and 43.85%,

respectively. The proportion of HCB also reached a maximum (10.51%) in the fall. In

contrast, the proportion of the rest OCPs in all three seasons were lower than 10%.


85

Fig. 1. temporal-spatial variations of OCPs, HCHs, DDTs and HCB in the SPM

Source apportionment of major OCPs in the SPM

The possible sources of major OCPs can be identified by looking at the isomer ratios of

these pesticides (Iwata et al. 1995). The ratios of α-/γ-HCH and β-/(α+γ)-HCH indicated that

the recent use of lindane was the primary source of HCHs in the SPM. The ratios of o,p’-

/p,p’-DDT and DDT/(DDD+DDE) indicated that residual DDTs in SPM were mainly derived

from the new inputs of industrial DDT. The α-/γ-chlordane ratio of most samples was less

than 0.77, indicating that there was a recent input of industrial chlordane in Lake Chaohu.

Potential ecological risk

The Consensus-Based Sediment Quality Guidelines (CB-SQGs) (MacDonald et al., 2000)

were used to evaluate the potential ecological risk of OCPs in the SPM. The results showed

that γ-HCH, p,p’-DDE and ΣDDTs might have a negative impact on aquatic organisms, and

that p,p’-DDT and o,p’-DDT had the greatest risks.

CONCLUSIONS

Seventeen types of OCPs were detected in the SPM samples. HCHs and DDTs were found

as two dominant OCPs and with high residual levels. Their possible sources were the recent

illegal use of lindane and industrial DDT. HCHs and DDTs might have adverse effects on

aquatic organisms.

ACKNOWLEDGEMENTS

The funding was provided by the National Science Foundation of China (NSFC)

(41030529 and 40725004).

REFERENCES Iwata H, Tanabe S, Ueda K, Tatsukawa R (1995) Persistent organochlorine residues in air, water, sediments,

and soils from the Lake Baikal region, Russia. Environmental Science & Technology 29:792–801

MacDonald DD, Ingersoll CG, Berger TA (2000) Development and evaluation of consensus-based sediment

quality guidelines for freshwater ecosystems. Archives of Environment Contamination and Toxicology 39:20-31

Tao S, Liu WX, Li Y, Yang Y, Zuo Q, Li BG, Cao J (2008) Organochlorine pesticides contaminated surface soil

as reemission source in the Haihe Plain, China. Environmental Science & Technology 42:8395-8400


86

Using stable isotope analysis in vegetated flow-through stream

mesocosms to study aquatic-terrestrial subsidies (O.104)

Matthias V. Wieczoreka, Denise Kötter

a, René Gergs

a and Ralf Schulz

a

aInstitute for Environmental Sciences, Fortstraße 7, Landau, 76829, Germany

INTRODUCTION

Emergence of aquatic insects provides a considerable energy subsidy to riparian food

webs but may also serve as a vector for contaminant residues (Walters 2008). Therefore

riparian food webs are at risk to be adversely affected by aquatic contamination. The

objective of the present study was to develop an integrated stream mesocosms test design

capable of identifying these inter-habit effects and, furthermore, providing a comprehensive

approach for current ecotoxicological testing within the scope of Regulation (EC) No.

1107/2009. We chose the widely distributed web-building spider Tetragnatha extensa as a

representative species for riparian predators. Trophic aspects of riparian food webs were

investigated by stable isotope analysis, carbon (δ13

C) and nitrogen (δ15

N).

METHODS

The present study was performed at 4 of the 16 stream mesocosms at the University

Koblenz-Landau, Campus Landau (Germany). Each stream channel is 45 m long and 0.4 m

wide. The channels contained a sediment layer of 9 cm consisting of sieved top soil and were

equipped with the helophyte Berula erecta. The mesocosm system was run in recirculation

mode with flow rates up to 3 L/s. Meshed cages were placed above the vegetated stream

mesocosms each comprising a strip of a terrestrial model meadow ecosystem and a part of the

respective aquatic stream section. Four individuals of T. extensa were placed in each meshed

cage for a time period of one month. For qualitative and quantitative determination of

emerging insects, emergence tents were placed above the stream mesocosms and additional

meadow strips and were sampled in 48 – 72 h intervals and stored at -18°C. Subsequent to

taxonomic determination, stable isotope ratios of δ13

C and nitrogen δ15

N were measured in

spiders and their potential prey, including aquatic and terrestrial insects. Data analysis was

performed with R (package: SIAR).


The analysis of stable δ13

C and nitrogen δ15

N isotope ratios revealed the trophic

relationships of the present stream mesocosm community, comprising emerging terrestrial

and aquatic insect species and the predatory spider T. extensa. Data analysis of prey and

spider samples showed that the overall emergence predominantly consisted of aquatic

emergence (>70 %). Stability and reproducibility in general were shown for the present

stream mesocosms. The test system was stable regarding abiotic water parameters and no

significant differences in community composition of the four mesocosms were observed

(PERMANOVA).


87

Figure 1. δ

13C and δ

15N values (mean ± SD) of terrestrial and aquatic arthropods. Each replicate of

aquatic arthropods (n = 8) is composed of at least one individual. The replicates of T. extensa (n = 8) are

composed of 18 individuals with minimum of one individual per replicate. Due to low terrestrial

emergence, δ13

C and δ15

N values are composed of reduced replicates: Staphylinidae (n = 3), Empididae (n

= 3), Tipulidae (n = 4) and Cicadellidae (n = 8) with at least 3 individuals per replicate.

CONCLUSION

Evaluation of the present study indicates that the use of stable isotopes ratios in

ecotoxicological stream mesocosm studies can provide a tool to identify contaminant related

effects of aquatic pollution on riparian food web structure. Therefore, the inclusion of land-

water interactions such as trophic cross-ecosystem linkages in ecotoxicological stream

mesocosm studies might be a relevant future application to obtain and create more realistic

test scenarios.

ACKNOWLEGEMENTS

We thank various academic staff of the Institute for Environmental Sciences who

performed the stable isotope analysis and supported use over the whole experimental phase

and the data analysis.

REFERENCES Walters, D. M., K. M. Fritz, and R. R. Otter. 2008: The dark side of subsidies: adult stream insects export

organic contaminants to riparian predators. Ecological Applications 18:1835–1841.


88

Mechanisms controlling metal/metalloid accumulation in organic

rich sediments (O.3)

Jörg Schallera

aInstitute of General Ecology and Environmental Protection, University of Technology

Dresden, PF 1117, 01737 Tharandt, Germany. Email: [email protected]

INTRODUCTION

Organic sediments are known to be a significant sink of inorganic elements and metal

pollutants in contaminated ecosystems. Metal / metalloid content of detritus has been shown

to increase significantly during decomposition. However the role of the decomposer

community in this fixation and the factors that make sediments a sink of metals and

metalloids remains unclear. Furthermore, the possible effect of nutrients availability during

decay and especially the availability of silicon on metal fixation is not fully understood.

Consequently, we made experiments to test these factor in regard to their impact to metal

fixation.

METHODS

Laboratory batch experiments were conducted to assess the effect of different functional

groups of invertebrates and different litter types (grown under high and low silicon

availability) on metal fixation during litter decomposition.


During decomposition, invertebrate shredder as an ecosystem engineer significantly

facilitated the enrichment of magnesium (250%), manganese (560%), cobalt (310%), copper

(200%), zinc (43%), arsenic (670%), cadmium (100%) and lead (1340%) into small particle

sizes. The enrichments occurred under very high concentrations of dissolved organic carbon.

Smaller particles have higher surface area that results in higher biofilm development. Further,

the highest amounts of elements were observed in biofilms. Therefore, invertebrate shredders

can enhance retention of large amounts of metal and arsenic in wetlands. Furthermore, we

found clear effects of bioturbators like the tube dwelling Chironomus plumosus.

In addition, the results of the silicon experiment are a significantly higher metal/metalloid

accumulation during decomposition of plant litter grown under low silicon availability

(Fig. 1). This may be explained by the altered litter properties (mainly nutrient content)

affecting the microbial decomposition of the litter, the microbial growth on the litter and

possibly by the silicon double layer, which is evident in leaf litter with high silicon content

and reduces the binding sites for metals/metalloids. Furthermore, this silicon double layer

may also reduce the growing biofilm by reducing the availability of carbon compounds at the

litter surface and has to be elucidated in further research. Hence, low silicon availability

during plant growth enhances the metal/metalloid accumulation into plant litter during

aquatic decomposition.


89

Fig. 1. Effect of silicon availability on metal fixation during litter decay from Schaller (2013).

CONCLUSIONS

In conclusion, the process of litter decay controls the metal fixation by organic matter.

This effect is enhanced by invertebrate shredder. Bioturbators as another functional animal

group significantly affect the remobilization/fixation of metals within organic rich sediments.

In addition, silicon availability during plant growth impact the metal fixation during decay of

the plant material as a part of organic rich sediments.

REFERENCES Schaller, J. 2013. Metal/metalloid fixation by litter during decomposition affected by silicon availability during

plant growth. Chemosphere 90:2534-2538.


90

Mining wastewater treatment by steel slag reactive filters (O.57)

Yves Comeaua, Dominique Claveau-Mallet

a, Scott Wallace

b

aPolytechnique Montréal, P.O. box 6079, Station Centre-Ville, Montreal (QC) CANADA

H3C 3A7 ([email protected]; [email protected])

bNaturally Wallace Consulting, 109 E. Myrtle Street, Stillwater, MN 55082, USA

INTRODUCTION

Management of closed mining sites is a major environmental issue. In particular, mining

leachates produced from contaminated rain and surface water have to be treated before being

discharged. In this project, we were interested in the orphan Joplin gypsum mine, located in

Missouri. The current lime precipitation system is deficient and discharge criteria for

phosphorus, fluoride and metals are not met. The objective of the project was to propose a

replacement treatment system that would be efficient and economical. The tested system was

a steel slag constructed wetland. It was previously shown that steel slag removes efficiently

phosphorus (Drizo et al., 2006; Vohla et al., 2011), but its utilization for the treatment of

multi-components wastewater remains not well documented. Limitations concerning the use

of slag filters are high pH at the effluent, clogging and a sharp decline in efficiency

(Chazarenc et al., 2008).

METHODS

Lab-scale tests were conducted using slag filters and synthetic mining wastewater.

Plexiglas columns (length 17 cm and diameter 15 cm) were bottom fed with two synthetic

wastewaters representing diluted and concentrated leachates. The wastewater composition

was pH 6.9-5.7, Al 1.7-8.2 mg/L, Mn 0.24-0.83 mg/L, Zn 0.20-3.3 mg/L, o-PO4 11-107 mg

P/L and F 9-37 mg/L. Two types of slag were tested: electric arc furnace (EAF) slag from

Fort Smith, Arkansas and EAF slag from Blytheville, Arkansas. Void hydraulic retention

time (HRTV) of columns was between 4.3 and 19.2 h. Water was sampled at the outlet of

columns and analysed for pH, phosphorus, fluoride, calcium, manganese, zinc and

aluminium. Precipitates formed in filters were sampled at the end of tests and analysed by X-

ray diffraction for composition and crystal size. A schematic of the experimental system is

presented in Figure 1.

Fig. 1. Schematic of the experimental setup.

Fort Smith Blytheville

Type of Upstream Downstream Duration

wastewater columns columns (d)

High

conc.

3A

HRTV = 14.5 h

3B

HRTV = 17.3 h169

Type of slag

1A

HRTV = 14.2 h

1B

HRTV = 18.2 h162

Low

conc. 4A

HRTV = 4.8 h

4B

HRTV = 4.3 h145

5A

HRTV = 19.2 h

5B

HRTV = 14.6 h179

2A

HRTV = 17.2 h

2B

HRTV = 17.2 h222


91


Simultaneous removal of phosphorus, fluoride and metals by a slag filter was shown to be

possible and efficient. The best system was composed of two successive Fort Smith slag

filters with a total HRTV of 34 hours. Its overall removal was 99,9%, 85.3%, 98.0% and

99.3% for P, F, Mn and Zn, respectively. The system was efficient for the whole test duration

(179 days), however, a decrease in efficiency and pH was observed after 70 days in the

upstream column.

Fig. 2. Influent and effluent concentration from two successive Fort Smith slag filters operated at total

HRTV of 34 h.

Phosphorus and metals removal was related with a high pH in the effluent. Fluoride

removal was also related to high pH in the effluent but also to the F/P ratio in the wastewater.

With a high F/P ratio (0.88 by mass), soluble fluoride was in excess for the precipitation of

fluoroapatite, reducing the fluoride removal efficiency (10%). Fluoride removal was higher

(85%) at lower F/P ratio (0.33 by mass). Fluoride was removed more efficiently by the

Blytheville slag (>90%) then by the Fort Smith one (75%).

The proposed mechanism for P removal was precipitation of apatite and crystal growth.

Apatite growth rate was related to the phosphorus concentration in the wastewater. Calcite

crystals growth was identified as a competing mechanism to P removal (Claveau-Mallet et

al., 2013).

CONCLUSIONS

A constructed wetland composed of Fort Smith EAF slag was suitable for the treatment of

a mining wastewater containing a high concentration of phosphorus (as much as 110 mg

P/L), fluoride and metals.

Fluoride removal in slag filters was favoured by a low F/P ratio in the wastewater.

Apatite crystal growth was the main P removal mechanisms in steel slag filters.

REFERENCES Chazarenc, F., Kacem, M., Gerente, C. and Andres, Y. (2008) 'Active' filters: a mini-review on the use of

industrial by-products for upgrading phosphorus removal from treatment wetlands. 11th

Conference on Wetland

Systems for Water Pollution Control, November 1-7. Indore, India, International Water Association.

Claveau-Mallet, D., Wallace, S. and Comeau, Y. (2013). Removal of phosphorus, fluoride and metals from a

gypsum mining leachate using steel slag filters. Water Research. 47(4): 15-12-1520.

Drizo, A., Forget, C., Comeau, Y. and Chapuis, R. (2006) Phosphorus removal by steel slag and serpentinite.

Water Research. 40(8): 1547-1554.

Vohla, C., Koiv, M., Bavor, H. J., Chazarenc, F. and Mander, U. (2011). Filter materials for phosphorus

removal from wastewater in treatment wetlands - A review. Ecological Engineering. 37(1): 70-89.

0.0001

0.001

0.01

0.1

1

10

100

PO4-P F Mn Zn Al

co

ncen

etr

ati

on

(m

g/L

)

PO4-P


92

Metals removal in 8 different configurations of horizontal

constructed wetlands (O.60)

Anna Pedescollab

, Ricardo Sidrach-Cardonab, Eloy Bécares

a

a Ecology Section, Department of Biodiversity and Environmental Management, University

of León, Campus de Vegazana s/n, 24071 León, Spain ([email protected]).

b Environmental Institute, c/ La Serna 56, 24007 León, Spain.

INTRODUCTION

Although constructed wetlands (CWs) are a suitable technology for wastewater treatment,

mainly in small communities (García et al., 2010), we still know little about the behaviour of

these systems. In this work we tried to understand how these systems work depending of its

design configuration, by means the analysis of metal removal.

METHODS

Eight mesocosms-scale CWs were built inside the facilities of the León WWTP, in the

Northwest of Spain. Each CW consisted of a fibreglass container measuring 80 cm wide, 130

cm long and 55 cm high, which differed from each other in the design configuration.

Characteristics of the CWs are listed in Table 1. The experimental plant was operated from

May 2007 to December 2010. The wetlands were fed with homogenised wastewater from the

primary settler of the León WWTP at a hydraulic loading rate of 50 mmd-1

(CW6’ received

100 mmd-1

) with a continuous flow rate. Table 1. Main characteristics of the wetlands of the experimental plant.

CW Plant species Flow type

Gravel

matrix

(cm)

Water

depth

(cm)

Outlet

pipe

position

Organic load

(g BOD5m-2

d-1

)

CW1 Typha

angustifolia

Hydroponic (Floating

macrophytes)

Without

gravel 30 Top 3-10

CW2 Typha

angustifolia

Free water surface

(FWS) 25 50 Top 3-10

CW3 Typha

angustifolia FWS 25 50 Bottom 3-10

CW4 Unplanted FWS 25 50 Bottom 3-10

CW5 Phragmites

australis

Hydroponic (Floating

macrophytes)

Without

gravel 30 Bottom 3-10

CW6 Phragmites

australis Subsurface flow (SSF) 50 45 Bottom 3-10

CW6’ Phragmites

australis SSF 50 45 Bottom 6-20

CW7 Unplanted SSF 50 45 Bottom 3-10

Samples of inlet and outlet were taken in summer and winter campaigns and analysed for

different metals concentration (Fe, As, Ni and Pb).


The experimental plant was efficient in Pb removal (with efficiencies ranging from 79% to

92%). Effluent concentrations were in the range of other studies for all the metals (Lesage et

al., 2007) although differences were observed between CWs depending on the metal analysed

(Fig. 1). Thus, strict subsurface flow systems (CW6, CW6’ and CW7) were less efficient in

Fe and As removal. In fact, these systems released Fe and As, which can be related with


93

redox conditions within the wetlands (Galletti et al., 2010; Lesage et al., 2007). SSF wetlands

were more reduced than FWS systems (CW2, CW3 and CW4).

Fig. 1. Metals concentration for the influent and for outlet samples of the experimental plant for winter

and summer campaigns. Concentrations are expressed in gL-1

.

Moreover, clearly differences were observed between winter and summer sampling

campaigns. Also redox conditions presented seasonality because of the higher plant and

microbial activity in summer (García et al., 2010).

CONCLUSIONS

Metals analysed in this study seemed to be more affected by flow type (FWS and

hydroponic vs. SSF) and seasonality than other design factors, such as plant species or the

gravel matrix. In this sense, FWS flow would be more suitable conditions for metal removal,

due to the more oxidised conditions within these systems.

ACKNOWLEDGEMENTS

This study was funded by the Spanish Ministry of Science through the projects CTM2005-

06457-C05-03 and CTM2008-06676-C05-03/TECNO. Anna Pedescoll acknowledges the

Juan de la Cierva Programme of the Spanish Ministry of Science and Innovation.

REFERENCES Lesage, E., Rousseau, D.P.L., Meers, E., Tack, F.M.G., De Paw, N. (2007) Accumulation of metals in a

horizontal subsurface flow constructed wetlands treating domestic wastewater in Flanders, Belgium. Science of

the Total Environment 380, 102-115.

Galletti, A., Verlicchi, P., Ranieri, E. (2010) Removal and accumulation of Cu, Ni and Zn in horizontal

subsurface flow constructed wetlands: Contribution of vegetation and filling medium. Science of the Total

Environment 408, 5097-5105.

García, J., Rousseau, D.P.L., Morató, J., Lesage, E., Matamoros, V., Bayona, J.M. (2010) Contaminant removal

processes in subsurface flow constructed wetlands: A review. Critical Reviews in Environmental Science and

Technology 40(7), 561-661.

Inf CW1 CW2 CW3 CW4 CW5 CW6 CW6' CW7

As

0

5

10

15

20

25

30


Fe

0

10000

20000

30000 Winter

Summer


Ni

0

5

10

15

20

25


Pb

0

2

4

6

8

10


94

Pharmaceuticals in a Subsurface Flow Constructed Wetland and

Two Ponds (O.128)

S. Rühmlanda, A. Wick

b, T.A. Ternes

b, M. Barjenbruch

a

aTechnische Universität Berlin, Department of Urban Water Management FG Siedlungswasserwirtschaft, Sekr.

TIB 1-B16, Gustav-Meyer-Allee 25, Berlin, 13355, GERMANY www.siwawi.tu-berlin.de

([email protected])

bFederal Institute of Hydrology, Department of Water Chemistry, Am Mainzer Tor 1, Koblenz, 56068,

GERMANY ([email protected]; [email protected])

INTRODUCTION

Micropollutants can have an impact on ecosystems. For example, the antimicrobial

Sulfamethoxazole (SMX) is able to alter the composition of microbial communities and

hinder their nitrate reduction capacity at concentrations as low as 1.3 µg/L (Underwood et al.

2011). Constructed wetlands and ponds provide various options for the elimination

(degradation, absorption) of pharmaceuticals. This study examinates the treatment

performance of three different designs at a technical scale with emphasis on the redox

conditions.

METHODS Layout of Constructed Wetland (CW) and Ponds

The CW and the ponds were built and planted in 2004 and 2005. They are fed with the

same effluent from a large conventional wastewater treatment plant with nutrient removal in

the outskirts of Berlin in Germany. The hydraulic loading was 50 mm/d. The following

treatment plants were examined:

•Sandy SSF: sandy subsurface flow wetland, 1,320 m², water level constantly above filter

bed, estimated HRT = 11 d, O2 = 0.2 mg/l, redox potential = -150 mV

•Pond with floating plants: floating aquatic plant system, planted with Iris pseudacorus,

Scirpus sp. and Carex sp., 1,520 m², estimated HRT = 5.5 d, O2 = 0.2 mg/l, redox potential =

-140 mV

•Unplanted pond, 1,550 m², estimated HRT = 4 d, O2 = 2.2 mg/l, redox potential = -30 mV

The oxygen concentrations and redox potentials given above are the averages of five

measurements at the outlets in August 2012. Sampling and Analysis

The influent was sampled four times with an automatic sampler for 24 hours each. Seven

grab samples were taken at the effluents of the three cells. Sampling took place between

August 13th and August 31st 2012. The weather was dry in general and the air temperature

was around 20°C during the day.

The samples were filtered through 0.45 µm syringe filters made of regenerated cellulose

and a surrogate mix was added to a final concentration of 200 ng/L. The samples were

analysed by direct injection with a LC-MS/MS system (QTrap® 5500, AB Sciex, Darmstadt,

Germany). The injection volume was 80 µL and the chromatographic separation was

achieved using a Zorbax Eclipse Plus C-18 (2.1 x 150 mm, 3.5 µm, Agilent Technologies,

Waldbronn, Germany). All target compounds were measured within one chromatographic run

by scheduled multiple reaction monitoring (sMRM) using electrospray ionization (ESI) both

in negative and positive mode. At least two mass transitions were measured for quantification

and confirmation. An internal standard calibration was used for quantification. For quality


95

assurance samples were also fortified with the target compounds at a level of 200 ng/L and

1000 ng/L. Results were only considered valid if the recovery was in the range of 75-125%.


Consistent with their known persistence, the antiepileptic carbamazepine (CBZ) and the

artificial sweetener acesulfame were not significantly removed (<25%) by the three different

treatment systems. However, for 40 of the 53 measured target compounds a significant

removal of >30% could be observed at least for one of the treatment systems. For example,

diclofenac was diminished from 2.2 to 0.3 µg/L in the unplanted pond, which corresponds to

a removal of 82 ± 4% (see table). The pond with floating plants and the SSF showed lower

removal efficiencies of 65 ± 8 and 20 ± 19%, respectively. As diclofenac is a compound

known to be sensitive to photochemical degradation (Poiger et al., 2001), the different

removal efficiencies of diclofenac in the three treatment systems might be caused by their

different exposure to sunlight.

Table. Influent concentrations [µg/L] and elimination efficiencies of the treatment systems

subsurface flow wetland (SSF), pond with floating plants and unplanted pond

The results for other micropollutants also revealed that the removal efficiencies strongly

depend on the specific treatment system. For example, the results indicated that the good

supply with oxygen (oxic biodegradation) and/or light (photochemical degradation) in the

unplanted pond significantly enhanced the conversion of venlafaxine (VLX), VLX-

metabolites, CBZ-metabolites and the betablocker metoprolol. Gasser et al. (2012) made the

same observations for VLX and its metabolites. On the other hand, very low redox potentials

seem to be favourable to remove SMX which is also consistent with results of Mohatt et al.

Compound

Influent, n=4

Treatment Cell

Elimination, n=7

concentration

[µg/L]

95% confidence

interval [%] [%]

statistical

error [%]

Diclofenac 2.2 18 SSF 20 19

(analgesic) Pond floating pl. 65 8

Pond 82 4

Carbamazepine (CBZ) 2.2 9 SSF ≤0 16

(antiepileptic) Pond floating pl. 15 17

Pond ≤0 11

2-Hydroxy-CBZ 0.21 10 SSF 9 16

(CBZ-metabolite) Pond floating pl. 35 14

Pond 65 5

3-Hydroxy-CBZ 0.27 16 SSF ≤0 27

(CBZ-metabolite) Pond floating pl. 34 16

Pond 79 4

Venlafaxine (VLX) 0.50 10 SSF 53 9

(antidepressant) Pond floating pl. 76 5

Pond 81 3

N-Desmethyl-VLX 0.12 13 SSF 49 9

(VLX-metabolite) Pond floating pl. 60 9

Pond 72 4

O-Desmethyl-VLX 1.7 14 SSF 24 14


Pond 83 5

N,O-Didesmethyl-VLX 0.33 15 SSF 15 17


Pond 75 7

Sulfamethoxazole (SMX) 0.32 36 SSF 60 15

(sulfonamide antibiotic) Pond floating pl. 53 20

Pond 30 26

∑ SMX, Acetyl-SMX 0.46 22 SSF 70 7

Pond floating pl. 61 12

Pond 44 12

Metoprolol 2.0 7 SSF 64 5

(betablocker) Pond floating pl. 73 4

Pond 92 3


96

(2011). While the concentration of SMX (including the conjugate acetyl-SMX) decreased by

70 ± 7% in the SSF, SMX was only removed by 44 ± 12% under more aerobic conditions in

the uncovered pond.

CONCLUSION

Constructed wetlands and ponds are able to further diminish certain micropollutants

following a municipal wastewater treatment plant. The design of the treatment system

determines whether degradable compounds under anaerobic or under aerobic conditions are

removed.

REFERENCES Gasser, G.; Pankratov, I.; Elhanany, S.; Werner, P.; Gun, J.; Gelman, F.; Lev, O. (2012) Field and laboratroy

studies of the fate and enantioneric enrichment of venlafaxine and O-desmethyolvenlafaxine under aerobic

and anaerobic conditions. Chemosphere 88:98–105.

Mohatt, J., Hu, L., Finneran, K., Strathmann, T. (2011) Microbially Mediated Abiotic Transformation of the

Antimicrobial Agent Sulfamethoxazole under Iron-Reducing Soil Conditions. Environmental Science &

Technology 45:4793-4801.

Poiger, T., Buser, H.-R., Müller, M. (2001) Photodegradation of the pharmaceutical drug diclofenac in a lake:

pathways, field measurements, and mathematical modeling. Environ. Toxicol. Chem. 20(2):256-263.

Underwood, Jennifer C.; Harvey, Ronald W.; Metge, David W.; Repert, Deborah A.; Baumgartner, Laura K.;

Smith, Richard L. (2011) Effects of the Antimicrobial Sulfamethoxazole on Groundwater Bacterial

Enrichment. Environment Science and Technology 45:3096–3101.


97

Phragmites sp. Ability to Conjugate Alachlor (O.137)

Renata Ferreiraa, Vanessa Romon

b, Magda Fernandes

a, Augusto Etchegaray

b,

Susete Martins-Diasa

a Institute for Biotechnology and Bioengineering, Centre of Biological and Chemical Engineering, Department

of Bioengineering, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, PORTUGAL

([email protected] - [email protected] - [email protected])

b Faculty of Chemistry, PUC-Campinas, Rod. D. Pedro I, Km 186, Campinas, SP, 13086-900, BRAZIL

([email protected] - [email protected])

INTRODUCTION

The extent of herbicides routinely applied in agricultural intensely augmented over the

years and consequently, environmental and human health risks also increased. Constructed

wetlands (CWs) have been used as a cost-effective and sustainable treatment method for the

retention and degradation of organic contaminants in agricultural ecosystems (Kadlec and

Wallace, 2009). Plants are unique organisms equipped with notable metabolic and absorption

skills, along with transport systems that can take up nutrients or contaminants selectively

from the growth matrix, soil or water. Following uptake, the lipophilic xenobiotic is

converted into a more water-soluble and less toxic metabolite that can therefore be

eliminated. Glutathione S-transferases (GSTs) are a family of isozymes that catalyse the

conjugation of glutathione to several xenobiotics and thus play a central role in detoxification

mechanisms of eukaryotes and prokaryotes. In plants, these enzymes gained particular

attention with respect to detoxification of herbicides. Alachlor is an herbicide from the

chloroacetanilide family that is widely used for the control of annual grasses and broadleaf

weeds in a variety of major crops (e.g. maize, corn and soybeans). It is absorbed in the roots

and transferred to the upper parts of the plant through the apoplast, inhibiting the elongation

of the root system and the development of the shoots of young plants (Labrou et al., 2005).

While integrated in CWs, Phragmites should play an important role on phytoremediation

of domestic, agricultural and industrial wastewaters. The aim of the present work was to

evaluate Phragmites sp. ability to conjugate alachlor, and therefore contribute to the

understanding and potential use of reed plants in CWs for the treatment of agriculture runoff.

METHODS

Phragmites leaves were collected from a pilot-scale horizontal flow constructed wetland

that had been fed with tap water, installed at IST university campus, and immediately frozen

in liquid nitrogen. The plant material was ground to powder in a pre-cooled mortar using a

pestle under liquid nitrogen. Protein crude extract (CE) was prepared according to Davis and

Swanson (2001). A control of GST activity was measured using 10g of CE and 1-chloro-

2,4-dinitrobenzene (CDNB,1.6mM) and reduced glutathione (GSH, 20mM) as substrates.

The CDNB conjugate formation was followed at 340nm (9.6 mM-1

cm-1

) for 250 sec, at

25ºC. One unit (U) of GST specific activity was defined as 1mol of CDNB conjugated per

minute per g of protein. Alachlor conjugation reaction was accomplished using 141g of CE,

0.5mM GSH and 0.25mM alachlor. After incubation at 25ºC for 30 min, the reaction was

ended by adding 12L of 0.6M HCl and the precipitated proteins were removed by

centrifugation (12000×g, 5 min). Reactions without CE were used as blank. Alachlor-

glutathione conjugation reaction was followed by High Performance Liquid Chromatography

with Diode-Array Detection (HPLC-DAD) using a ZORBAX Eclipse XDB-C18 column

(4.6×150mm, 5m diameter). The column was eluted as described by Hatton et al. (1996) for

28 min. The eluent was monitored for UV absorbance at 220 (conjugation formation) and




98

264nm ( maximum of alachlor). After each run, the column was washed with acetonitrile for

12 min.


Glutathione conjugation with alachlor is catalysed by GST. In Phragmites leaves CE, GST

was active (198 ± 25 U). The obtained results presented specific activity levels similar to

previous studies (Carias et al., 2008). HPLC elution profiles are presented in Fig. 1. At

220nm, the increase of the peak at the retention time of 2.3 min is due to the addition of CE

(presence of more peptide bonds). The existence of a new peak, found at 22.5 min, was

indicative of alachlor-GS formation. Alachlor was consumed by the enzyme, as showed in

the chromatogram at 264 nm, by the reduction of the herbicide peak at 2.7 min.

Fig. 1. HPLC chromatograms of the reaction of alachlor and GSH with Phragmites leaf enzymatic crude

extract, monitored at = 220 nm and = 264 nm. Control - without Phragmites crude extract.

CONCLUSIONS

In the present work, GST extracted from Phragmites leaves were able to conjugate with

the herbicide alachlor. This work is a step forward in order to understand reed plants

tolerance towards chloroacetanilide herbicides. It may be concluded that Phragmites can

minimize the toxic effects of agriculture runoff contaminated with herbicides.

ACKNOWLEDGEMENTS

The authors acknowledge support from the Fundação para a Ciência e a Tecnologia

(PTDC/AAC-AMB/112032/2009).

REFERENCES Carias, C.C., Novais, J.M. and Martins-Dias, S. (2008) Are Phragmites australis enzymes involved in the

degradation of the textile azo dye acid orange 7? Bioresource Technol. 99:243-251.

Davis, D.G. and Swanson, H.R. (2001) Activity of stress-related enzymes in the perennial weed leafy spurge

(Euphorbia esula L.). Environ. Exp. Bot. 46:95-108.

Hatton, P.J., Dixon, D., Cole, D.J. and Edwards, R. (1996) Glutathione Transferase Activities and Herbicide

Selectivity in Maize and Associated Weed Species. Pesticide Science. 46:267-275.

Kadlec, R.H. and Wallace, S.D. (2009) Treatment Wetlands. CRC Press Boca Raton, Florida. 1016p.

Labrou, N., Karavangeli, M., Tsaftaris, A. and Clonis, Y. (2005) Kinetic analysis of maize glutathione S-

transferase I catalysing the detoxification from chloroacetanilide herbicides. Planta. 222:91-97.


99

Effect of hydrolysed polyacrylamide polymer contaminated oil

production water on batch-loaded surface flow wetland

mesocososms (O.142)

Stephane Prigenta, Tom Headley

b, Mitchell Kirby

a, James Johnston

a, Badar Al

Sharjib, Nasser Al-Azri

b, Roman Breuer

a

aBauer Nimr LLC P.O. Box 1186, Postal code 114, Al Mina Sultanate of Oman ([email protected] –

[email protected])

bPetroleum Development of Oman LLC, PO Box 81, Muscat, PC 100, Sultanate of Oman

INTRODUCTION

The Nimr Water Treatment Plant (NWTP) has been designed and built by the company

BAUER Nimr LLC in partnership with Petroleum Development Oman (PDO) for petroleum

produced water treatment in the southern desert of Oman. This treatment system has been

operating since 2010 and consists of a surface flow constructed wetland (SFCW) of 350 ha

planted primarily with Phragmites australis. The injection of polymer, such as hydrolysed

polyacrylamide (HPAM), into the Nimr oil reserve is currently planned by PDO, Oman’s

national oil company, in the forthcoming years to augment oil production. There are several

concerns surrounding the potential impacts of HPAM-contaminated produced water on the

operation of the oil separator, SFCW and salt work of the NWTP. The present study,

therefore, aimed to determine the preliminary effect of the use of HPAM on water quality,

plant health, evaporation, evapotranspiration at the NWTP.

METHODS

This experiment was carried out in 0.7 m3 (A = 1.2 m

2, H = 0.6 m) mesocosms

constructed from Intermediate Bulk Containers. Each mesocososm was filled, from the

bottom to the top, with 10cm of a coarse drainage gravel (Ø 18mm-24mm), 5cm of a fine

aggregate (Ø 2mm-10mm) and 20cm of soil substrate. In each planted mesocosm, 20

individual Phragmites australis seedlings were planted on 23rd

July, 2012. Triplicate

mesocosms were operated according to a range of treatment factors, such as HPAM

concentration (0ppm, 200ppm and 500ppm) and planting status (planted and non-planted

except for 500ppm) as shown on Table 1. Table 1: Treatment combinations of the batch-loaded experiment (Code: [0 or 200 or 500 ppm HPAM],[p

for planted or np for non-planted])

The experiment was set up and operated over a period of 5 months (Aug-Dec 2012), near

the NWTP. Six-day batch feeding was performed with well water (6ppt TDS) adjusted with

20-ppm oil in water and different HPAM concentrations (0ppm, 200ppm and 500ppm).

Water quality was monitored from the 10 cm deep water column five hours after “top up”

Code HPAM (ppm) Plants

0 200 500 + -

0,6,np x x

0,6,p x x

200,6,np x x

200,6,p x x

500,6,p x x


100

according to these following parameters: Conductivity (EC), pH, Dissolved Oxygen (DO),

Temperature, Total Dissolved Solids (TDS) and Oil-in-Water (OiW). Water loss was

measured every second day of operation before the mesocosms were topped up. The above

ground biomass was monitored according to a non-destructive method. Shoot height, shoot

density and leaf health were measured on three plant clumps selected at the beginning of the

experiment within the mesocosms. Statistical analysis was performed using a single factor

ANOVA test in Excel™.


The oil in water concentration of all treatments decreased to less than 0.5 mg.L-1

(detection limit) by the end of the six-day batches. The polymer treated plants reach an

average above ground biomass of 1000 g.m-2

by the end of the study (Figure 1). The reason

for the observed increase in growth in the HPAM treated mesocosms is likely due to nitrogen

content of the HPAM, which acted as a fertiliser for the plants under the otherwise nutrient

poor conditions. However, the difference in above ground biomass harvested between the

treatments was not statistically significant.

Figure 2: Dry weight of above ground biomass estimated over the study period

Polymer exposure seemed to increase the rate of leaf necrosis, with the plants exposed to

500 ppm HPAM showing the highest leaf yellowing and necrosis (85% of leaf dead after 6

weeks). This leaf necrosis could be related to increased uptake of boron, manganese, zinc,

molybdenum and nickel leading to higher concentrations in the leaves of the plants exposed

to HPAM. During the experiment, the evaporation rate was similar for both treated and

untreated mesocosms. After three months of establishment, the planted mesocosms receiving

200 ppm of HPAM displayed a higher average evapotranspiration than untreated mesocosms

(9 + 0.5 mm.d-1

). However, these results were not significant due to the high natural

variability amongst the replicates.

CONCLUSIONS

Reed growth and evapotranspiration rates, in some replicates, increased in response to the

polymer. However, results were not consistent across all of the replicated mesocosms and

therefore did not yield statistically significant differences between treatments. This was partly

due to scale limitations of the small mesocosms and short timeframe of the study.

Furthermore, several limitations could be pointed out such as the immature age of the plants

at the beginning of the experiment and the feeding method (batch loading). Therefore, a long-

term experiment is needed in a full scale SFCW to get a comprehensive answer on the effect

of polymer on the NWTP.

ACKNOWLEDGEMENTS

The authors are grateful to Professor H. Brix on his support to the collection and reed

leaves analysis from the NWTP.


101

Treatment of Refinery Effluent Using Vertical Subsurface

Constructed Wetlands: A Case Study in the Tropics (O.144)

Hassana Ibrahim Mustaphaa,c

, J. J. A. van Bruggenb, P. N. L. Lens

a

a Department of Environmental Engineering and Water Technology, Pollution Prevention and

Resource Recovery, UNESCO-IHE, Institute for Water Education, P. O. Box 3015, 2601 DA

Delft, The NETHERLANDS ([email protected]) b

Department of Water Science and Engineering, UNESCO-IHE, Institute for Water

Education, P. O. Box 3015, 2601 DA Delft, The NETHERLANDS (h.vanbruggen@unesco-

ihe.org) a Department of Environmental Engineering and Water Technology, Pollution Prevention and

Resource Recovery Core, UNESCO-IHE, Institute for Water Education, P. O. Box 3015,

2601 DA Delft, The NETHERLANDS ([email protected]) c Federal University of Technology Minna, Department of Agricultural and Bioresources

Engineering, P. M. B 65, Minna, Gidan Kwano Campus. NIGERIA

INTRODUCTION

Industrialization is a very important tool in every nation's economy, at present; it is the main

source of hazardous pollutant into water bodies (Akhavan et al., 2008), particularly in

developing countries where stringent discharge rules are not observed. Most of the people's

livelihood in the developing countries depends on river water for farming, fishing and for

domestic purposes and as sources of soil amendments and for irrigation purposes (Agbenin et

al., 2009). Untreated or partially treated industrial wastewater channeled into the environment

and used for agricultural purposes, for animal consumptions or other purposes pose

considerable environmental problems. Conventional methods are energy intensive and are

very expensive for developing countries to afford; likewise, these methods generate by-

products that are often toxic to both human and the environment and require further treatment

(Ojumu et al., 2005). Constructed wetland technologies may offer a lower construction and

maintenance cost for wastewater treatment, which is especially suitable for developing

countries, also most of the developing countries are found in the tropics where constructed

wetlands are suitable due to the high temperature which enhances biodegradation activity

(Kantawanichkul et al., 1999).

METHODS

This study was conducted at the Kaduna Refinery and Petrochemical Company, Kaduna

(Kaduna South, Nigeria), which lies between latitude 9 0 N and 12

0 N and Longitude 6

0E

and 9 0 E within the Northern guinea savannah ecological zone of Nigeria. The refinery

effluents were treated by chemical addition, clarification, oxidation, oil skimming, filtration

and evaporation before being discharged via drainages into Romi stream. The conducted

experiment was a two-phase experiment. The first phase consisted of characterization of the

primary treated refinery effluent and the second phase addressed constituents of concern in

the final discharged effluent by using artificial vertical subsurface flow constructed wetlands

(VSSF).

The primary treated effluents samples were collected once every month from the final

discharge channel from September, 2011 to December, 2012 for characterization in order to

obtain baseline information on the quality of wastewater discharged into the environment.

Standard methods for Examination of Water and Wastewater were used.

Two VSSF units and duplicates were constructed with 47 cm in diameter and 55 cm in

height. These were planted with Typha latifolia as an alternative to achieve treatment of


102

effluents to non-hazardous levels. The media used was gravel; three different sizes were used

starting at the bottom with 25-36mm, middle portion with size range of 16-25 mm and the top

of the unit with 6-10 mm in size. The refinery effluents were fed gradually by gravity from a

5000 L tank into the wetland units at flow rate of 35L/day and hydraulic retention time of 7

days.

RESULTS

The discharged effluent from the refinery contained high levels of TSS ( 336 mg/l), BOD (

283 mg/l), COD ( 521 mg/l), turbidity (253 mg/l), ammonia (13 mg/l), phosphate (16 mg/l),

potassium (31 mg/l), Cd (0.03 mg/l), Cr (3.4 mg/l), Pb (0.06 mg/l), phenol (1.16µg/L ) and

oil and grease (14 mg/l) which were higher than the permissible discharge limits. There was a

good reduction in the concentration of BOD, COD, ammonia and turbidity with removal

efficiency of 75%, 67%, 51% and 83.98% for BOD, COD, ammonia and turbidity

respectively.

CONCLUSIONS

Typha planted vertical subsurface flow constructed wetlands units were able to reduce the

concentration of BOD, COD, ammonia and turbidity from secondary treated refinery

wastewater.

ACKNOWLEDGEMENTS

The author acknowledges the Netherlands Fellowship Program (NFP) for their financial

support. Dr. Ibrahim El-Idris and staff and management of Kaduna Refinery and

Petrochemical Company, Kaduna, Nigeria are also acknowledged for their support.

REFERENCES Agbenin J. O., Danko, M., and Welp, G (2009). Soil and vegetable compositional relationships of eight

potentially toxic metals in urban garden fields from northern Nigeria, J. Sci. Food Agric. 89:49-54

Akhavan, S. A., Dejban Golpasha, I., Emani, M and Nakhoda, A. M (2008). Isolation and characterization of

crude oil degrading Bacillus spp., Iran. J. Environ. Health. Sci. Eng., 5 (3):149-154

Ojumu, T. V., Beelo, O. O, Sonibara, J. A and Solomon, B .O (2005). Evaluation of microbial systems for

bioremediation of petroleum refinery effluents in Nigeria, African Journal of Biotechnology, 4 (1): 31-35

Kantawanichkul, S., Pilaila, S., Tanapiyawanich, W., Tikampornpittaya, W and Kamkrua, S (1999). Wastewater

treatment by tropical plants in vertical-flow constructed wetlands. Wat. Sci. Tech. 40 (3): 173-178.


103

Storage of agricultural drained water by a pond / reservoir

system to reduce nitrate and pesticides transfer (O.147)

Tournebize J.a, Chaumont C.

a, Fesneau C.

a, Mänder Ü.

a

aIrstea, Hydrosystems and Bioprocesses Research Unit, 1 rue Pierre Gilles de Genes, F92761 Antony, FRANCE

([email protected] – [email protected] – [email protected])

INTRODUCTION

Agricultural non-point source pollution is of increasing concern as attested by the

implementation of new regulations like the European Water Framework Directive

2000/60/EC. To comply with these regulations, actions can be taken at different scales. At the

local scale, fertilizers and pesticide application rate reduction should first be implemented.

However, complementary actions at the watershed scale are needed since remaining applied

molecules will transfer from the watershed to natural receiving waters. Among them,

artificial wetlands including pond and reservoir are suspected to be able to provide nitrate and

pesticides mitigation. The aim of this study is to observe the efficiency of a pond/reservoir to

remove nitrate and pesticides from agricultural drainage water in intensive agricultural

catchment located in Ile de France region of France, over the period 2007-2012.

METHODS

A man-made pond and reservoir used as a constructed wetland for this study is located in

Aulnoy, France, 70 km northeast of Paris (figure 1). The pond and reservoir measure 860 and

3305 m2, respectively, and a total estimated storage volume of 10,000 m

3. The ratio between

the pond/reservoir surface and the agricultural catchment surface is 1.2%. The study site is

located inside the Orgeval catchment belonging to a water quality research observatory. The

climate is oceanic temperate with a mean annual temperature and precipitation of 12°C and

700mm respectively. The agricultural catchment of 33 hectares is located in the sedimentary

Paris Basin. The agricultural land is subsurface drained using perforated pipe installed 10m

apart and buried 0.8-1m to enable soil cultivation during winter. Cereals (corn, maize),

legumes (horse bean, pea), sugar beet or rape are the dominant crops grown in the region.

Drainage collector as inlet of pond/reservoir and outlet of pond/reservoir were equipped with

hourly water level sensor and a 90° V – notch sections and a weekly flow proportional

sampler. Over 30 pesticides were analysed during 5 years.

Figure 3. Experimental pond/reservoir location at outlet of a 33ha agricultural watershed belonging to

Orgeval Observatory (Seine et Marne, France)

0 40 km 0 200 m

33-ha agricultural

catchment totally

drained

Main drain

Orgeval catchment

Bec

k

N N

Pond

Spring

Overflow10 m

Reservoir

Outflow

Main drain

N

0 40 km 0 200 m

33-ha agricultural

catchment totally

drained

Main drain

Orgeval catchment

Bec

k

NN NN

Pond

Spring

Overflow10 m

Reservoir

Outflow

Main drain

NN


104


Nitrate concentration between inlet and outlet were reduced from an average value of

63mg/L to 23mg/L in the pond/reservoir system. Punctual investigations showed that

denitrification is the main dissipation process. Nevertheless N2 or N2O emissions were not

monitored to confirm or not the total denitrification reaction. In the whole about 50% of

nitrate fluxes were removed from the annual drained water.

Pesticides transfer depended strongly on farmer practices. Pesticides exportations from the

drained watershed were linked to date and applied amount over the crop as well as pesticides

properties (Koc and DT50). The average concentrations were slightly reduced, showing

nevertheless elevated concentration mitigation. It was not possible to determine if

degradation or simple dilution was the main process. In term of annual fluxes, some sorbing

pesticides showed 100% removal efficiency, whereas mobile pesticides less than 30%. Note

that 3 pesticides showed negative removal efficiency, highlighting a possible desorption

process.

The pond/reservoir system allowed storing about 14% of annual drained water. This high

volume led to a 300m3 per drained hectare ratio. In this context, hydraulic residential time

varied between few weeks during winter to months during summer. Removal efficiency

depended on seasonal variation as well. Global mitigations were about 50% and 46% for

nitrate and pesticides respectively. Those results are comparable with literature values.

Figure 4. Nitrate and pesticides concentrations at inlet and outlet of the pond/reservoir system during

2007-2012

CONCLUSIONS

A pond/reservoir system as buffer zone between agricultural land and surface water body

appeared to be a good complementary action to reduce nitrate and pesticides transfer by a

factor 2. Hydraulic residential time and temperature seemed to be the main parameters

controlling removal efficiency. Two questions remained unsolved yet dealing with GES

emissions from denitrification process for nitrate and desorption process for pesticides.

Should we wait before recommending this such land management helping to reduce nonpoint

source pollution from subsurface drained watershed?

Inlet Outlet

Pes

tici

de

Co

nce

ntr

ati

on

(µ

g/l

)

Inlet Outlet


105

Behaviour of dimethylphenol isomers in the rhizosphere of

Juncus effusus (O.68)

L. Schultze-Nobre, A. Wiessner, U. Kappelmeyer, P. Kuschk

Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research

- UFZ, Permoserstraße 15, Leipzig, D-04318, GERMANY ([email protected] -

[email protected] - [email protected] - [email protected])

INTRODUCTION

In future a renaissance of coal pyrolysis industry is predicted replacing the petrochemistry

resulting in the revival of new waste water treatment plants with new treatment methods.

Constructed wetlands (CWs) could be a relatively new option in the complex sequence of

physicochemical and biological treatment processes which are applied nowadays. We could

not found enough and consistently experimental results in the literature about 2,6-DMP

elimination in anaerobic process. Aim of the present study was to forecast the fate of

dimethylphenols (DMPs) as effluent constituents of coal pyrolysis and petrochemical

industries in CWs. Because of the low degradation potential under anaerobic condition

(Thomas and Lester, 1993; Puig-Grajales et al., 2000) models experiments were realized

simulating the root zone of horizontal subsurface-flow constructed wetlands where a mosaic

structure of aerobic and anaerobic zones can be expected (Winter and Kickuth, 1989)

METHODS

A laboratory-scale planted fixed bed reactor (PFBR) simulating the microgradient of

rhizosphere zone of constructed wetlands (Kappelmeyer et al., 2002;

Wiessner et al., 2005) planted with Juncus Effusus (see Fig. 1) is

established. The reactor was fed with synthetic wastewater containing a

mixture of 2,6-, 3,4- and 3,5- DMP-isomers in a equimolar ratio as the

only organic carbon contaminants. Experimental phases with different

inflow concentrations of total DMPs were investigated resulting in case of

the lower inflow concentration of 15.7 mg C/L aerobic and in case of the

higher inflow concentration of 78.7 mg C/L anaerobic conditions in the

soil pore water of the reactor. Fig. 1: PFBR


In aerobic conditions Fig.2 - A,B and D

3,4, 3,5- and 2,6-DMP were almost eliminated

respectively.

In anaerobic condition Fig. 2 - D the

removal efficiency were less than in

aerobic condition

and the elimination rate worsened over

time. Better removal were founded by 3,4-

> 3,5- > 2,6-DMP.

Fig. 2: Data from long-term research of 3,4-, 3,5- and 2,6-DMP-C removal in a laboratory-scale PFBR


106

CONCLUSIONS

We have successfully studied the elimination processes of 2,6-DMP under aerobic and

anaerobic conditions. Our long-term research findings shows that DMP can be removed in

aerobic and anaerobic operated conditions in a laboratory scale planted reactor system.

Better removal were obtained with 3,4- > 3,5- > 2,6-DMP. Our experimental results in

comparison with the literature shows that 2,6-DMP can be also removed by anaerobic

conditions using a PFBR.

ACKNOWLEDGEMENTS

This work was supported by the Helmholtz Centre for Environmental Research – UFZ in

the scope of the SAFIRA II Research Program: Revitalization of Contaminated Land and

Groundwater at Megasites, project “Compartment Transfer”. Further funding was provided

by the Helmholtz Interdisciplinary Graduate School for Environmental Research

(HIGRADE) (Bissinger and Kolditz, 2008).

REFERENCES Bissinger, V. and Kolditz, O. (2008) Helmholtz Interdisciplinary Graduate School for Environmental Research

(HIGRADE). Gaia-Ecological Perspectives for Science and Society, 17, 71-73.

Kappelmeyer, U., Wießner, A., Kuschk, P. and Kaestner, M. (2002) Operation of a Universal Test Unit for

Planted Soil Filters - Planted Fixed Bed Reactor. Eng. Life Sci., 2, 311-315.

Puig-Grajales, L., Tan, N. G., van der Zee, F., Razo-Flores, E. and Field, J. A. (2000) Anaerobic

biodegradability of alkylphenols and fuel oxygenates in the presence of alternative electron acceptors. Applied

microbiology and biotechnology, 54, 692 - 697.

Thomas, A. O. and Lester, J. N. (1993) THE MICROBIAL REMEDIATION OF FORMER GASWORKS

SITES - A REVIEW. Environmental Technology, 14, 1-24.

Wiessner, A., Kappelmeyer, U., Kuschk, P. and Kastner, M. (2005) Influence of the redox condition dynamics

on the removal efficiency of a laboratory-scale constructed wetland. Water Res, 39, 248-256.

Winter, M. and Kickuth, R. (1989) Elimination of sulphur compounds from wastewater by the root zone process

- II. mode of formation of sulphur deposits.

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