Hg in Buyat

7/29/2019 Hg in Buyat

1/17

Heavy metal contamination from gold mining recorded in Porites lobata skeletons,

Buyat-Ratototok district, North Sulawesi, Indonesia

Evan N. Edinger a,b,c,*, Karem Azmy c, Wilfredo Diegor c, P. Raja Siregar d

a Department of Geography, Memorial University, St. Johns, NL, Canada A1B 3X9b Department of Biology, Memorial University, St. Johns, NL, Canada A1B 3X9c Department of Earth Sciences, Memorial University, St. Johns, NL, Canada A1B 3X9d Indonesian Forum for the Environment (WALHI), Jl. Tegal Parang Utara No. 14, Jakarta 12790, Indonesia

a r t i c l e i n f o

Keywords:

Submarine mine tailings

Arsenic

Laser ablation ICP-MS

Coral skeleton

Porites lobata

Indonesia

a b s t r a c t

Shallow marine sediments and fringing coral reefs of the Buyat-Ratototok district of North Sulawesi,

Indonesia, are affected by submarine disposal of tailings from industrial gold mining and by small-scale

gold mining using mercury amalgamation. Between-site variation in heavy metal concentrations in shal-

lowmarine sediments was partially reflected by trace elementconcentrations in reef coral skeletons from

adjacent reefs. Corals skeletons recorded silicon, manganese, iron, copper, chromium, cobalt, antimony,

thallium, and lead in different concentrations according to proximity to sources, but arsenic concentra-

tions in corals were not significantly different among sites. Temporal analysis found that peak concentra-

tions of arsenic and chromium generally coincided with peak concentrations of silica and/or copper,

suggesting that most trace elements in the coral skeleton were incorporated into detrital siliciclastic sed-

iments, rather than impurities within skeletal aragonite.

2008 Elsevier Ltd. All rights reserved.

1. Introduction

Retroactive determination of heavy metal concentrations prior

to anthropogenic activities is often crucial to understanding the

environmental impacts of those activities, particularly in locations

where these activities have had a long history. Such retroactive

determination is particularly difficult in coastal marine environ-

ments, where bioturbation can obscure the temporal record of met-

als in sediments. Coral skeletons have been used extensively to

record the history of metal pollution from dredging, mining, terres-

trial runoff, and other sources on coral reefs (Brown and Holley,

1982; Howard and Brown, 1984, 1987; Anderegg et al., 1997; Scott

and Davies, 1997; Esslemont, 1999, 2000; Fallon et al., 2002; David,

2003; Runnalls and Coleman, 2003). The ability of corals to record

metal pollution varies among metals, due to differences in solubil-

ity and differences in the degree to which trace elements can be

incorporated into aragonite crystal lattice (Howard and Brown,

1984). Arsenic and mercury, two of the principal contaminants

from gold mining, present analytical challenges in this context.

The atomic radius of arsenic is incompatible with the dimensions

of the aragonite crystal lattice, therefore arsenic incorporated into

coral skeletons is thought to be primarily detrital, having entered

the coral skeletonas incorporated siliciclastic sediment, rather than

as dissolved metal. Mercury presents analytical challenges due to

its volatility, which requires distinct analytical techniques for

mercury in sediments from techniques used for most other metals.

Traditionally, studies of trace elements in coral skeletons have

relied upon mechanical sampling followed by chemical analysis

using atomic absorbtion spectroscopy (AAS, e.g. Khaled et al.,

2003), inductively coupled plasma atomic emission spectroscopy

(ICP-AES or ICP-OES, optical emission spectroscopy e.g. Bastidas

and Garcia, 1997; David, 2003), or solution inductively-coupled

plasma-mass spectrometry (ICP-MS, e.g. Scott and Davies, 1997).

Of these methods, ICP-MS is the most sensitive, and has the great

advantage of analyzing a wide suite of elements simultaneously

(Scott and Davies, 1997).

Several recent research efforts relating to coral skeletal records

of pollution have used laser ablation mass-spectrometry (LAM-

ICPMS) to reconstruct the history of trace element pollution from

coral skeletons (Fallon et al., 2002; Runnalls and Coleman, 2003).

Laser ablation has several advantages over traditional analytical

methods, including ability to extract precisely located samples

from within the coral skeleton, ability to measure concentrations

of a wide range of elements simultaneously, and direct introduc-

tion of sample to the analytical instrument, thus skipping exten-

sive cleaning, dissolution and possibilities of contamination or

operator error associated with wet chemistry (Veinott, 2001).

Laser ablation may also introduce some challenges, however.

Laser ablation ICP-MS may induce fractionation of some isotopes

as the ablation pit becomes deep (Eggins et al., 1998; Gunther

0025-326X/$ - see front matter 2008 Elsevier Ltd. All rights reserved.doi:10.1016/j.marpolbul.2008.05.028

* Corresponding author. Address: Department of Geography, Memorial Univer-

sity, St. Johns, Canada NL A1B 3X9. Tel.: +1 709 737 3233; fax: +1 709 737 3119.

E-mail address: [email protected] (E.N. Edinger).

Marine Pollution Bulletin 56 (2008) 15531569

Contents lists available at ScienceDirect

Marine Pollution Bulletin

j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / m a r p o l b u l
mailto:[email protected]://www.sciencedirect.com/science/journal/0025326Xhttp://www.elsevier.com/locate/marpolbulhttp://www.elsevier.com/locate/marpolbulhttp://www.sciencedirect.com/science/journal/0025326Xmailto:[email protected]


2/17

and Hattendorf, 2001), and laser ablation necessarily mixes lattice-

bound trace elements incorporated from solution with those in-

cluded within the skeleton as detrital sediment (e.g. Runnalls and

Coleman, 2003). Finally, for metals that are heterogeneously dis-

tributed within the skeleton, the high spatial precision of off-the-

shelf laser ablation IPC-MS systems may contribute to high inter-

sample variation that obscures broader patterns.

The objectives of this paper are (1) to compare spatial patterns

of trace element concentration in marine sediments with those in

coral skeletons, and (2) to examine temporal patterns in trace ele-

ment concentrations in coral skeletons as a historical record of

contamination from gold mining activities. We present trace ele-

ment concentrations and chronologies from Porites lobata corals

collected on reefs adjacent to two distinct types of gold mining

activities: submarine tailings disposal of industrial gold mine tail-

ings, and small-scale gold mining using mercury amalgamation in

coastal watersheds. Our results show that coral skeletons can re-

cord trace element contamination from distinct types of gold min-

ing activities, including trace elements that are normally not

incorporated into aragonite coral skeletons. In addition, we address

two methodological points, (1) comparing whole-sediment and


3/17

mental danger on the basis of the low dissolved metal concentra-

tions (PTNMR, 2002b), but elevated arsenic and antimony concen-

trations in shallow marine sediments suggest tailings dispersal at

least 1 km northeast, and at least 3 km southeast, of the tailings

outfall, in waters as shallow as 20 m (Edinger et al., 2007). Arsenic

in tailings includes both geochemically stable and reactive forms,

but antimony in tailings is mostly stable (Blackwood and Edinger,

2007).

1.1.2. Small-scale mining

Small-scale mining in Indonesia releases large fluxes of mercury

to air and water, contributing mercury to fish consumed by hu-

mans (Kambey et al., 2001; Limbong et al., 2003). In the region

of this study, artisanal gold miners operated extensively in the To-

tok and Kotabunan watersheds (Fig. 1) until approximately 1989,

although artisanal gold mining continues to a much lesser extent

in both areas. No small-scale mining has occurred in the Buyat Riv-

er watershed. Concentration of arsenic, cobalt, copper, and other

metals in sediments affected by artisanal mining was slightly high-

er than in regional pre-mining background analyses, possibly due

to enhanced erosion associated with mining activities (Edinger

et al., 2007).

2. Materials and methods

2.1. Sampling areas

Field sampling took place on fringing reefs of Buyat and Totok

Bays (Fig. 1). Buyat Bay (approximately 050.40N/12442.30E) is a

small bay exposed to wave action from the Molucca Sea. The Buyat

River debouches at the NW corner of the bay, and a coarse sand

tombolo separates Buyat Bay from Totok Bay. The east side of Buy-

at Bay hosts fringing coral reefs; the reefs closest to the beach are

now completely dead, while those monitored by the mining com-

pany, in the outer portion of the bay and along the outer margin of

the Ratototok Peninsula are in better condition (PTNMR, 2002b).

Maximum depth in the bay is approximately 90 m. The shelf re-

mains relatively flat until reaching the shelf break at about

120 m depth, roughly 8 km from shore, from which point the bot-

tom descends to bathyal depths (PTNMR, 1994). The shape of the

Buyat River mouth, visible plumes of sediment from the Buyat Riv-

er, and PTNMR current meter data suggest that surface currents

generally flow counter-clockwise around the bay. Bottom currents

appear to follow a similar pattern (PTNMR, 1994, 2002a, b).

Totok Bay (approximately 0520N/12442.70E) is a larger bay

protected from wave action by the Ratototok Peninsula. Coastlines

are mangroves along the protected side of the tombolo separating

Totok Bay from Buyat Bay and along the northern margins of the

bay, fringing coral reefs along the inner side of the Ratototok Pen-

insula and the islands in the bay, and cleared mangrove in front of

Ratototok village, and adjacent to the mouth of the Totok River.Maximum depth is about 100 m. The shape of sand spits suggests

that currents in Totok Bay generally flow in a counter-clockwise

direction around the bay.

The climate is monsoonal, with a rainy season November to

April, and dry season May to October. Sea surface temperatures

range from 27 to30 C (PTNMR, 1994). Tides in the region are mixed

semi-diurnal and microtidal, with a spring tide range of approxi-

mately 1.2 m.

2.2. Sediment sample collection and analysis

Reef sediments and coral skeletons were collected in June 2002

(17 sediment samples, BY01-18), with further sediment samplingin August 2004 (25 sediment samples, BY21-52). Sediment analysis

characterized end-members of sediment in the system, including

three primary sources: artisanal gold mining (the Totok River

and Kotabunan River) industrial gold mine tailings disposed in

Buyat Bay, and the Buyat river, which drains the mine site and

has similar bedrock geology to the Totok River watershed (Edinger

et al., 2007). Background sediment composition was determined

from two sources: the sites furthest to sea in Totok Bay (BY15,

BY45 and BY51), and the description of marine sediments collected

in 1993 for the industrial gold mines Environmental Impact

Assessment (PTNMR, 1994).

Sediment samples were collected using a hand-operated Petit-

Ponar grab sampler deployed from a motorized outrigger canoe

or fishing boat. Position of sampling station positions were re-corded using a hand-held GPS. Depth was determined by the

length of grab sampler rope; depth measurements associated with

grab samples are therefore maximum depth estimates. Visual

descriptions of sediment colour, grain size, and bulk composition

(carbonate vs. siliciclastic) were recorded in the field, with subse-

quent measurement of grain size distribution and carbonate con-

tent in the lab. All samples were frozen immediately upon return

to shore and kept frozen until analysis.

2.3. Sediment trace element analysis

Three gram sediment subsamples were dry-sieved through a

0.063 mm polyurethane mesh to account for grain-size related

biases in sediment chemistry. Sediment subsamples were homog-enized by stirring, dried, ground to


4/17

where 0.40 is the weight percent Ca in CaCO3. Although this method

could overestimate the carbonate content of sediments by including

Ca from volcanic rocks, the weight percent of Ca in calcium carbon-

ate is more than three times that of the weight percent Ca of calcic

plagioclase, such that nearly all Ca was probably present as CaCO 3.

Pre-mining sediment chemistry is reported as the average of 31

marine sediment samples from Buyat Bay and environs, as reported

in the mining companys original environmental impact assessment

(PTNMR, 1994).

Fig. 2. X-ray negative of coral skeleton BY04L, showing density bands. Approximate

track of carbonate sampling and laser ablation analysis indicated by dashed black

line. White scale bar 1 cm.

Table 2

Sediment (


5/17

2.5. Coral skeleton sample collection and analysis

Domal P. lobata corals were collected whole from approxi-

mately 1 m below low tide on seven fringing reefs surrounding

Buyat Bay and Totok Bay. Sites BY04, BY05, BY07, BY08, and

BY10 were all from fringing reefs surrounding Buyat Bay. Site

BY14 is a small fringing reef near the mouth of the Totok River. Site

BY15 is a fringing reef on the southwest corner of Pulau Babi, in To-

tok Bay, approximately 3 km from the Totok River, and serves as a

reference site for the Totok River. Coral skeletons were cut in half

vertically and air dried in the field prior to shipment to Canada,

where all further analysis took place.

Coral skeletons were cut into 810 mm thick slabs parallel to

growth lines using a diamond blade rock saw cooled with tap

water. Coral skeleton slabs were rinsed with distilled water after

cutting, and etched in 0.2 N HNO3 prior to analysis. Each coral skel-

eton slab was X-rayed to reveal density bands (Fig. 2). For each cor-

al, the slab showing the clearest banding, and for which the cut

was most clearly parallel to corallites, was selected for further

analysis. Analyses did not follow the axial growth direction of

the coral, hence distance between growth bands does not directly

reflect coral skeletal extension rates (Edinger et al., 2000).

2.6. Coral skeleton stable isotope sampling and analysis

To verify that density bands in coral skeletons were annual

growth bands, and to assure time control within coral skeletons,

d13C and d18O of coral skeleton aragonite were analyzed in coral

BY04, and Sr/Ca ratios of coral skeletal aragonite were analyzed

in all samples (see below). Small subsamples of skeleton, approx-

imately 320 lg, were drilled from the skeletons along lines per-

pendicular to growth banding at 2 mm increments. Samples

were reacted in inert atmosphere with ultrapure concentrated

orthophosphoric acid at 72 C in a Thermo-Finnigan Gasbench

II; the produced CO2 was automatically delivered to a Thermo-

Finnigan Delta-plus XP isotope ratio mass spectrometer in a

stream of helium and measured for isotope ratios. Laboratory

standards NBS-18 and NBS-19 were repeatedly measured during

each analysis run and yielded a routine precision better than 0.1

per mille.

2.7. Coral skeleton trace element concentrations

Coral skeleton trace element concentrations were analyzed

using laser ablation-ICPMS. Coral skeleton slabs were cut to

46 23 6 mm (standard thin-section size) blocks for insertion

into the laser ablation sample cell. Distance down the coral skele-

ton was recorded to the nearest 10 lm using the position of the

sampling carriage. A NuWave UP 213 nm NdYAG laser system

was interfaced to an HP 4500 quadrupole ICPMS with argon as

the plasma gas, and helium as the carrier gas. The laser was set

to 80 um spot size at 10 Hz, yielding an average beam intensity

of 0.5 mJ, equivalent to 11 J/cm2. In all analyses, 44Ca was used as

the internal standard. Analyses were conducted on three days:

November 14, 2005, November 17, 2005, and August 31, 2006.

Each run of 20 analyses included four analyses of NBS 610 glass

standard, three analyses of MACS-1 coral aragonite reference

material, and at least one duplicate analysis of coral skeleton from

the same vertical position within the coral skeleton. In coral BY04,

laser ablation spots were matched to the position of the drill holes

for carbonate d13C and d18O analyses. Because of the open skeletal

nature of P. lobata, analyses did not strictly follow corallite walls.

Duplicate analyses were run to check for consistency, and in cases

where the initial run displayed significant yield attenuation.

Fig. 4. Trace element concentrations in sediments (


6/17

Trace element concentrations in coral skeletons were calibrated

to the NBS 610 fused glass standard, rather than the MACS-1 car-

bonate reference material, because there are, as yet, no published

certified values for MACS-1. Instead, the MACS standard was used

for quality control. The relative standard deviation (RSD) and stan-

dard error (sd/n1/2) of each element measured was calculated for

the MACS standard, as a measure of the consistency with which

the laser-ablated carbonates released each element to the mass

spectrometer. The results from the LA-ICPMS analyses of the MACS

standard were compared to data obtained by solution ICPMS done

in the same lab, using the procedure described for sediment trace

element analysis.

2.8. Data analysis

Prior to statistical analysis, repeat coral skeleton trace element

concentration data were screened to assess variability and to con-

solidate repeat analyses. Repeat analyses for which the initial abla-

tion signal displayed significant attenuation were removed.

Second, the average of repeat analyses was calculated for pairs that

both had consistent yield. Because concentrations of trace ele-

ments in coral skeletons appeared non-normal, concentrations

were compared among sites using exploratory data analysis(EDA) and the KruskallWallis test. Correlation coefficients among

the elements analyzed in all coral skeleton ablations were calcu-

lated using bivariate linear correlation of log-transformed concen-

trations. Correspondence between metal concentrations in the


7/17

including the tailings, and 1570% in reef sediments (Table 2). Car-

bonates in reef sediments were easily recognizable as poorly-

sorted, angular, very coarse-grained bioclasts from corals, calcare-

ous algae and molluscs, while carbonates in fluvial and non-reefal

sediments were mostly subangular crystalline detrital carbonates

(Fig. 3).

Most sediment samples were >70% siliciclastic, except BY05,

BY07, BY08, BY10, BY15, BY29, and BY51 (Fig. 3; see Appendix 1).

Of the siliciclastic samples, most were dominantly siliciclastic

mud, except for shallow nearshore samples BY07, BY09, BY11,

BY39, BY41, and BY52, collected near the mouths of the Buyat, To-

tok, and Kotabunan rivers, and samples BY16, 17, and 18, collected

in the Buyat and Totok rivers (Table 2, Appendix 1). The samples

collected near the end of the tailings pipe were fine silts.

3.2. Sediment trace element concentrations

3.2.1. Sediment sample analytical accuracy and precision

Duplicate analyses of identical samples for sediment metal con-

centrations (n = 4 pairs) yielded results differing by


8/17

fractions of sediments from the two Totok Bay reefs, while anti-

mony concentrations in Totok Bay reef sediments were 12 times

elevated in the mud fraction over whole sediment values.

3.3. Coral skeletal metal analyses

3.3.1. Laser ablation and solution ICP-MS analysis of MACS-1 reference

materialAmong the oxides and elements considered here, MgO, Al2O3,

Ti, V, As, Sb, and Tl had RSD values greater than 50%, while SiO2,

FeO, Cr, Mn, Co, Ni, Cu, Zn, Ba, and Pb had RSD values less than

40% (Table 5). RSD for Sr ranged from 12% to 20%, with the highest

value observed in 84Sr, and the lowest in 86Sr.

Laser ablation analyses of MACS-1 for SiO2, Ti, V, Mn, As, and Tl

differed from solution analyses by 100% or more, while analyses for

FeO, Cr, Co, Ni, Cu, Zn, Sb, Ba, and Pb differed from the solution

analysis by less than 50%.

3.3.2. Variation in coral skeleton trace element concentrations amongreefs

Median aluminum oxide concentrations were lowest in corals

from exposed, siliciclastic poor sites BY08 and BY10 (Fig. 5A,

0.05

0.04

0.03

0.02

0.01

0.00

BY05-11

BY05-20

BY04L-31

BY10-17

BY15-22

BY08-40r

BY14-1

BY14-5

BY07-16BY05-19r BY14-21

0.35

0.30

0.25

0.20

0.15

0.10

0.05

0.00

BY10-01

BY05-13

BY10-03

BY15-13

BY08-8r

0.50

0.40

0.30

0.20

0.10

0.00

BY10-17BY08-13

BY14-1

BY14-3BY07-7

By05-1

BY04L-4

BY10-10BY08-12

BY08-15

BY07-5

0.12

0.10

0.08

0.06

0.04

0.02

0.00

BY04L-42

BY04L-38

BY14-1

BY07-5

By05-1

BY04L-33

BY10-01BY15-19r

BY08-7

BY07-3

BY04 BY 07 BY 08 BY 10 BY 14 BY 15BY 05

BY04 BY 07 BY 08 BY 10 BY 14 BY 15BY 05 BY04 BY 07 BY 08 BY 10 BY 14 BY 15BY 05

BY04 BY 07 BY 08 BY 10 BY 14 BY 15BY 05

A

lO

wt%

2

3

S

iO

wt%

2

MgO

wt%

FeO

wt%

A B

DC

Fig. 5. Boxplots showing major oxide concentrations in coral skeleton analyses. (A) Aluminum oxide, (B) silica, (C) magnesium oxide and (D) iron oxide concentrations in

coral skeletons.

Table 6

KruskallWallis tests comparing trace element concentrations in coral skeletons

Element or oxide Sediment group Rank order among corals Significance

Al2O3 Oxides, fluvial BY05 > BY04 = BY05 = BY14 = BY15 > BY08 > BY10 P< 0.001

SiO2 Oxides, fluvial BY14 > BY05 = BY04 > BY08 = BY10 > BY15 > BY07 P< 0.001

FeO Oxides, Fluvial BY05 > BY15 > BY08 = BY10 > BY14 > BY04 > BY07 P< 0.001

Cr Fluvial or tailings BY04 > BY07 = BY14 > BY05 = BY08 = BY10 > BY15 P< 0.001

Co Fluvial BY04 = BY08 > BY15 > BY05 > By07 = BY10 > BY14 P< 0.001

Cu Fluvial BY04 > BY15 > BY07 = BY10 > BY05 = BY08 = BY14 P< 0.001

Pb Fluvialartisanal BY05 > BY04 = BY08 > BY07 = BY10 > BY14 = BY15 P< 0.001

As Tailings BY04 = BY14 > BY05 = BY07 = BY08 = BY10 = BY15 P= 0.178

Sb Tailings BY04 > BY14 = BY05 = BY08 > BY07 > BY10 = BY15 P< 0.001

Tl Tailings BY04 > BY05 > BY08 = BY14 > BY10 = BY15 > BY07 P< 0.001

Sites: Reef closest to tailings: BY04, Tj. Buyat reef: BY05, Tj. Sikod: BY08, Ratototok Peninsula: BY10, Bobokan Reef (Buyat river mouth): BY07, Totok river mouth: BY14,Reference: BY15. Significance indicated by KruskallWallis test.

1560 E.N. Edinger et al. / Marine Pollution Bulletin 56 (2008) 15531569


9/17


10/17

Peak concentrations of arsenic and antimony in Tj. Buyat coral

BY10 were recorded in 2000, and coincided with a minor peak in

Cr, and with mildly elevated concentrations of SiO2, Cu, and Ba

(Fig. 8C). Smaller peaks in Sb and Cr co-occurred, and coincided

with Cu orSiO2 peaks, but not with peaks in Ba concentration. Peak

concentrations of As in Tj. Sikod coral BY08 occurred in 1996, 1997,

and 1999, with a minor peak in late 1998 (Fig. 8D). Peak concentra-

tions of As and Cr frequently co-occurred, but peaks in As and Sb

did not. Peak concentrations of As generally coincided with peaksin silica content.

Concentrations of As and Sb in Bobokan coral BY07 (near the

Buyat river mouth) were generally low, often close to the detection

limit for these elements (Fig. 9A). Peak concentrations of Cr in coral

BY07 occurred in 1998, 1999, and 2001, and generally coincided

with peaks in Ba, SiO2, and Cu. Peak concentrations of As and Sb

in coral BY14 (Totok River mouth) occurred in 1998, 1999, and

2001, with additional high concentrations recorded in the two

ablations closest to the upper surface of the coral (Fig. 9B). These

high concentrations probably resulted from remnant tissue con-

tamination of the material ablated. Peak concentrations of Sb and

Cu generally coincided with peak concentrations of SiO2, or to a

lesser extent, Cu, but had little apparent relationship with Ba con-

centrations, except for the elevated As and Sb concentrations in

2001. Concentrations of antimony in reference coral BY15 were

generally below detection limits (Fig. 9C). Arsenic concentrations

had low peaks in 1998, 2000, and near the top of the coral, but

these peaks did not have a clear correspondence with Ba, Cu, or

SiO2. Chromium peaks in BY15 were generally associated with

minor peaks in silica content. Two major peaks in Cu in 1999

2000 also coincided with increases in silica content.

3.4. Correlations between trace elements in sediments and in coral

skeletons

Trace element concentrations in sediments (


11/17

Table 7

Correlation matrix among elements recorded in coral skeletons, ln-transformed

MgO Al2O3 SiO2 CaO42 CaO43 FeO Co Cu Zn As Sb Ba Tl

Al2O3 0.060

SiO2 0.063 0.507**

CaO_42 0.040 0.002 0.038

CaO_43 0.016 0.002 0.165* 0.534**

FeO 0.077 0.646** 0.329** 0.006 0.168*

Co 0.117 0.069 0.022 0.002 0.037 0.09Cu 0.068 0.005 0.061 0.041 0.073 0.066 0.19**

Zn 0.008 0.11 0.258** 0.026 0.065 0.079 0.099 0.305**

As 0.034 0.294** 0.247** 0.143* 0.151* 0.215** 0.029 0.000 0.142*

Sb 0.016 0.006 0.252** 0.047 0.013 0.132 0.027 0.046 0.159* 0.226**

Ba 0.383** 0.128 0.141* 0.144* 0.087 0.308** 0.052 0.127 0.088 0.012 0.024

Tl 0.32 0.155* 0.261** 0.007 0.059 0.07 0.024 0.109 0.211** 0.204** 0.280** 0.052

Pb 0.133 0.047 0.141* 0.022 0.014 0.171* 0.034 0.234** 0.115 0.112 0.075 0.251** 0.067

** p < 0.01, * p < 0.05. N= 207 in all cases.

0

8

4

12

16

20

[Ba,

Cu

],ppm,

[Si/100]ppm

Ba

Cu

SiO /100

100 20 30 40 50 60 70 80 90 100

vertical distance (mm)

200

2

200

1

200

0

199

9

199

8

199

7

199

6

BY 04 (closest reef to tailings outfall)

18O

O

7.0

7.5

8.0

8.5

9.0

Sr/

Cammo

l/mo

l

9.5

As

Sb

Cr

0.0

0.4

1.6

0.8

1.2

2.0

[As,

Sb

,Cr]

Sr/Ca

-4.5

-5.0

-5.5

-6.0

-6.5

Fig. 8. Coral skeleton trace element chronologies: reef affected by industrial mine tailings. (A) Reef inside Buyat Bay (BY04). (B) Tj. Buyat (BY05). (C) Ratototok Peninsula(BY10); (D) Tj. Sikod (BY08). Annual bands (vertical grey bars) were identified using the skeletal density bands, and verified as annual using Sr/Ca ratios.

E.N. Edinger et al. / Marine Pollution Bulletin 56 (2008) 15531569 1563


12/17

elling with fine-grained silica from mine tailings, rather than pyritecrystalswith arsenicor antimony-rich rims (Blackwood and Edinger,

2007). Amorphous colloidal ironarsenic phases were observed intailings sediment and in sediments from Buyat Bay reef BY04 and

2002

2001

2000

1999

1998

7.0

7.5

8.0

8.5

9.0

Sr/Cammo

l/mol

9.5

5 10 15 20 25 30 35 40 45 50

0

8

4

12

16

20

[Ba,

Cu],ppm,

[Si/100]ppm

SiO /10

BaCu


BY 05 (500 m east of tailings outfall)

0.0

0.4

1.6

0.8

1.2

2.0

[As,

Sb

,Cr,]

As

Cr

Sb

7.0

7.5

8.0

8.5

9.0

Sr/

Cammo

l/mo

l

9.5

50 10 15 20 25 30 35 40 45

2002

2001

2000

1999

1998


BY 10 (1 km east of tailings outfall)

Sb

Cr

As

0.6

0.0

0.4

0.2

0.8

1.0

[As,

Sb

,Cr,

]

Cu

Si/100

Ba

0

8

4

12

16

20

[Ba,

Cu

],ppm,

[Si/100]ppm

Fig. 8 (continued)



13/17

Tj. Buyat Reef BY05 (Blackwood and Edinger, 2007). However, ironand arsenic peaks did not always coincide in skeletal chronologies,

and iron and arsenic were not correlated in coral skeletal analyses

from siteBY04,suggesting thatmuchof thearsenicin coral skeletons

may have been present as Mgarsenate, another tailings processing

by-product. Arsenic in Totok Bay reefs was likely present as fine-

grained arsenopyrite (Blackwood and Edinger, 2007); silt-sized

grains of arsenopyrite were observedin sediment from both the To-

tok and Buyat rivers (Blackwood and Edinger, 2007).

4.2. Influence of grain size on sediment trace element analyses

Sediment trace element analysis results for the mud fraction

were highly consistent with whole sediment concentrations previ-

ously reported for the same sites (Edinger et al., 2007; Table 4). Themajor differences encountered were at tailings-influenced sites

dominated by bioclastic reef sediment, particularly BY05, BY08,

and BY10 (Edinger et al., 2007). The fine fraction sediment data fur-

ther document dispersal of mine-tailings derived sediment onto

reefs 12 km away from the mine tailings outfall (Edinger et al.,

2007). The high degree of agreement between whole-sediment

and


14/17

various trace elements rather than a fused homogenized glass,inhomogeneities can be expected, particularly for elements incom-

patible with the aragonite crystal lattice. Similarly, differences inablation yield between the fused glass standard, the MACS

50 10 15 20 25 30 35 40 45

0

8

4

12

16

20

[Ba,

Cu],ppm,

[Si/100]ppm

Ba

Cu

SiO /100


2002

2001

2000

1999

BY 07 (closest to Buyat river mouth)

1998

As

Cr

Sb0.0

0.4

1.6

0.8

1.2

2.0

[As,

Sb,

Cr,]

7.5

8.0

8.5

9.0

Sr/C

ammol/mol

9.5

50 10 15 20 25 30 35 40 45


2002

2001

2000

1999

BY 14 (closest to Totok river mouth)

1998

0

8

4

12

16

20

[Ba,

Cu

],ppm,

[Si/100]ppm

Ba

Cu

SiO /100

As

Cr

Sb

0.0

0.4

1.6

0.8

1.2

2.0

[As,

Sb,

Cr,

]

8.0

8.5

9.0

9.5

10.0

Sr/

Cammo

l/mo

l

Fig. 9. Coral skeleton trace element chronologies: reef affected by fluvial runoff, artisanal mining, and reference site. (A) Bobokan, near Buyat river mouth (BY07); (B) Totok

River mouth (BY14), affected by artisanal mining; (C) Reference site, Pulau Babi, Totok Bay(BY15). Annual bands (vertical grey bars) were identified using theskeletal density

bands, and verified as annual using Sr/Ca ratios.



15/17

pressed-pellet carbonate reference material and the porous arago-

nitic coral skeletons may also contribute to analytical uncertainty.

Lateral variation in detrital material incorporation at a scale of

1001000 lm likely accounted for the high variability in most me-

tal chronologies, and the relatively low repeatability of laser abla-

tion analyses in the coral skeleton samples. Some laser ablation

ICP-MS systems have been modified to sample from a larger area

(50 500lm), rather than a discrete circular ablation pit (e.g. Sin-

clair et al., 1998; Fallon et al., 2002, 2003; Sinclair, 2005 ). Such a

modified laser ablation system could probably avoid some of the

problems with small-scale spatial heterogeneity observed in this

study, as it would average the element concentrations within a

wider area. Similarly, drilling out subsamples of coral skeleton

for solution analysis (cf. Shen and Boyle, 1989; Bastidas and Garcia,

1997; David, 2003) would likely yield a greater amount of total

material, possibly avoiding issues with


16/17


17/17

References

Anderegg, D., Dodge, R.E., Swart, P.K., Fisher, L. 1997. Barium chronologies from

South Florida reef corals environmental implications. In: Proceedings of

Eighth International Coral Reef Symposium, vol. 2, pp. 17251730.

Appleton, J.D., Williams, T.M., Orbea, H., Carrasco, M., 2001. Fluvial contamination

associated with artisanal gold mining in the Ponce Enriquez, Portovel-Zaruma

and Nambija areas, Ecuador. Water, Air, and Soil Pollution 131, 1939.

Aspinall, C. 2001. Small-scale mining in Indonesia. International Institute for

Environment and Development, Mining Minerals and Sustainable DevelopmentReport No. 79, 30 p.

Bastidas, C., Garcia, E., 1997. Metal content on the reef coral Porites astreoides: an

evaluation of river influence and 35 years of chronology. Marine Pollution

Bulletin 38, 899907.

Blackwood, G.M., Edinger, E.N., 2007. Mineralogy and trace element relative

solubility of coastal marine sediments affected by submarine tailings disposal

and small-scalegold mining, North Sulawesi, Indonesia. Environmental Geology

52, 803818.

Brown, B.E., Holley, M.C., 1982. Metal levels associated with tin dredging and

smelting and their effect upon intertidal reef flats at Ko Phuket, Thailand. Coral

Reefs 1, 131137.

Budd, A.F., Mann, K.O., Guzman, H.M., 1993. Environmental interpretation using

insoluble residues within reef coral skeletons: problems, pitfalls, and

preliminary results. Coral Reefs 12, 3142.

CCME (Canadian Council of Ministers of Environment) 2001. Canadian sediment

quality guidelines for the protection of aquatic life. Summary tables. Updated.

In: Canadian Environmental Quality Guidelines, Publication No. 1299, Canadian

Council of Ministers of the Environment, Winnipeg.

Cortes, J., Risk, M.J., 1985. A reef under siltation stress: Cahuita, Costa Rica. Bulletinof Marine Science 36, 339356.

David, C.P., 2003. Heavy metal concentrations in growth bands of corals: a record of

mine tailings input through time (Marinduque Island, Philippines). Marine

Pollution Bulletin 46, 187196.

Edinger, E.N., Limmon, G.V., Jompa, J., Widjatmoko, W., Heikoop, J.M., Risk, M.J.,

2000. Normal coral growth rates on dying reefs: are coral growth rates good

indicators of reef health? Marine Pollution Bulletin 40, 404425.

Edinger, E.N., Siregar, P.R., Blackwood, G.M., 2007. Heavy metal contamination of

shallow marine sediments from submarine tailings disposal and artisanal gold

mining, Buyat-Ratototok district, North Sulawesi, Indonesia. Environmental

Geology 52, 701714.

Eggins, S.M., Kinsley, L.P.J., Shelly, J.M.G., 1998. Deposition and element

fractionation processes during atmospheric pressure laser sampling for

analysis by ICP-MS. Applied Surface Science, 278286.

Esslemont, G., 1999. Heavy metals in corals from Heron Island and Darwin Harbour,

Australia. Marine Pollution Bulletin 17, 209213.

Esslemont, G., 2000. Heavy metals in seawater, marine sediments and corals from

the Townsville section, Great Barrier Reef Marine Park, Queensland. Marine

Chemistry 71, 215231.

Fallon, S.J., White, J.C., McCullock, M.T., 2002. Porites corals as recorders of mining

and environmental impacts: Misima Island, Papua New Guinea. Geochimica et

Cosmochimica Acta 66, 4562.

Fallon, S.J., McCulloch, M.T., Alibert, C., 2003. Examining water temperature proxies

in Porites corals from the Great Barrier Reef: a cross-shelf comparison. Coral

Reefs 22, 389404.

Gunther, D., Hattendorf, B., 2001. Elemental fractionation in LA-ICP-MS. In:

Sylvester, P. (Ed.), Laser-ablation-ICPMS in the Earth Sciences: Principles and

Applications, Mineralogical Association of CanadaShort CourseSeries, vol. 29,p.

8391.

Howard, L.S., Brown, B.E., 1984. Heavy metals and reef corals. Oceanography and

Marine Biology Annual Review 22, 195210.

Howard, L.S., Brown, B.E., 1987. Metals in Pocillopora damicornis exposed to tin

smelter effluent. Marine Pollution Bulletin 18, 451454.

Kambey, J.L., Farrell, A.P., Bendell-Young, L.I., 2001. Influence of illegal gold mining

on mercury levels in fish of North Sulawesis Minahasa Peninsula (Indonesia).

Environmental Pollution 114, 299302.Khaled, A., El-Nemr, A., El-Sikaily, A., 2003. Contamination of coral reef by heavy

metals along the Egyptian Red Sea Coast. Bulletin of Environmental

Contamination and Toxicology 71, 577584.

Limbong, D., Kumampung, J., Rimper, J., Arai, T., Miyazaki, N., 2003. Emissions and

environmental implications of mercury from artisanal gold mining in north

Sulawesi, Indonesia. Science of the Total Environment 302, 227236.

PTNMR (P.T. Newmont Minahasa Raya), 1994. Studi analisis dampak lingkungan

kegiatan pertambangan emas di Minahasa dan Bolaang Mongondow, Sulawesi

Utara, Indonesia. [Environmental Impact Analysis study of gold mining in

Minahasa and Bolaang Mongondow, North Sulawesi, Indonesia]. PT Newmont

Minahasa Raya, Jakarta, pp. 1487.

PTNMR 2002a. Minahasa Gold Mine Post-closure Submarine Tailings Modeling

Study. PT Newmont Minahasa Raya, Manado, pp. 131.

PTNMR 2002b. Minahasa Mine Closure Plan. PT Newmont Minahasa Raya, Manado,

pp. 1241.

Runnalls, L.A., Coleman, M.L., 2003. Record of natural and anthropogenic changes in

reef environments (Barbados West Indies) using laser ablation ICP-MS and

sclerochronology on coral cores. Coral Reefs 22, 416426.

Salomons, W., Forstner, U., 1984. Metals in the Hydrocycle. Springer, Berlin. p. 349.

Scott, P.J.B., Davies, M., 1997. Retroactive determination of industrial contaminants

in tropical marine communities. Marine Pollution Bulletin 34, 975980.

Shen, G.T., Boyle, E.A., 1989. Determination of lead, cadmium, and other trace

metals in annually-banded corals. Chemical Geology 67, 4762.

Sinclair, D.J., 2005. Correlated trace element vital effects in tropical corals: a new

geochemical tool for probing biomineralization. Geochimica et cosmochimica

acta 69, 32653284.

Sinclair, D.J., Kinsley, L.P., McCulloch, M.T., 1998. High resolution analysis of trace

elements in corals by laser ablation ICP-MS. Geochimica et cosmochimica acta

62, 18891901.

Turner, S.J., Flindell, P.A., Hendri, D., Hardjana, I., Lauricella, P.F., Lindsay, R.P.,

Marpaung, B., White, G.P., 1994. Sediment-hosted Gold Mineralisation in the

Ratatotok District, North Sulawesi, Indonesia. Journal of Geochemical

Exploration 50, 317336.

Veinott, G., 2001. The use of laser-ablation-ICP-MS in the environmental sciences.

In: Sylvester, P. (Ed.), Laser-ablation-ICPMS in the Earth Sciences: Principles and

Applications, Mineralogical Association of CanadaShort CourseSeries, vol. 29,p.

213224.Weeks, T., McGaffin, I., Loah, J., 1997. Whole ore treatment at PT Newmont

Minahasa Raya. World Gold 97. Australasian Institute of Mining and

Metallurgy, 141151.

Weeks, T., Wan, R.Y., 2000. Behavior of arsenic in refractory gold ore processinga

case study of PT Newmont Minahasa Raya. In: Young, C.A. (Ed.) Minor Elements

2000, Society of Mineral and Metals Exploration, Littleton, Colorado, pp. 125

133.

E.N. Edinger et al. / Marine Pollution Bulletin 56 (2008) 15531569 1569

Hg in Buyat

Documents

Transcript of Hg in Buyat