Prepared by: Gary JacobiPrepared by: Gary Jacobi

Extent of CCA Treated Wood in Consumer Mulches and Methods of

Detection

Extent of CCA Treated Wood in Consumer Mulches and Methods of

Detection

Mulch made from C&D WoodMulch made from C&D Wood

ObjectivesObjectives

Determine the extent to which CCA-treated wood has contaminated consumer mulches

Determine if visual methods can be used to identify suspect mulch

Determine if X-ray fluorescence (XRF) technology can be used to identify suspect mulch

Determine the extent to which CCA-treated wood has contaminated consumer mulches

Determine if visual methods can be used to identify suspect mulch

Determine if X-ray fluorescence (XRF) technology can be used to identify suspect mulch

Mulch Analysis MethodsMulch Analysis Methods

Sample

Visual Inspection

Size Distribution

Ash for Total Metals

SPLP AnalysisChemical Analysis

Physical Analysis

XRF Analysis

Visual InspectionVisual Inspection

Plywood and Foreign Objects (Nails, Plastic, Rubber, Glass, String, Rocks, Etc.)

Size DistributionSize Distribution

Uniformity Coefficient (UC): The UC will approach 1 if the pieces of sample

are the same size

d50: The size in inches that 50% of the sample is finer than

Uniformity Coefficient (UC): The UC will approach 1 if the pieces of sample

are the same size

d50: The size in inches that 50% of the sample is finer than

UC d60

d10

Sieve AnalysisSieve Analysis

Visual AnalysisVisual AnalysisVisual Analysis Category Fraction

of Samples

Number of Samples

Additional Information

Colored 52% 44 Of the colored samples, 36 were red, 6 were gold, and 2 were black

Contain Plywood 18% 15 Contain Particle Board 4% 3 Contained Oriented Strand Board

0% 0

Contained Painted Wood 7% 6 Contained Other Objects 12% 10 Other objects included, nails, rope,

string, plastic, rocks, and glass. Smooth/Straight Surfaces 60% 50 Pine Bark 56% 47 Of the 47 samples that contained pine

bark, 7 consisted of at least 95% pine bark

* 73% mulches with plywood are colored

Results: Size DistributionResults: Size Distribution

Average d50 of samples was 0.29 in.

Average Uniformity Coefficient was 5.0

Average d50 of samples was 0.29 in.

Average Uniformity Coefficient was 5.0

d50 Histogram

3

34

39

35

0

10

20

30

40

50

0 - 0.1 0.1 - 0.2 0.2 - 0.5 0.5 - 1 1 - 1.5

d50 (in)

Fre

qu

en

cy (

%)

UC Histogram

9

18

23

30

4

0

10

20

30

40

1 - 3 3 - 4 4 - 5 5 - 8 > 8

UC Range

Frequency

(%

)

Chemical AnalysisChemical Analysis

Sample

Visual Inspection

Size Distribution

Chemical Analysis

Physical Analysis

Ash for Total Metals

SPLP Analysis

XRF Analysis

Analysis ProcedureAnalysis Procedure Total MetalsResults

LeachableResults

XRF

Ashed Samples: 84

44

31 13 4 36

40

Results: Ash for Total MetalsResults: Ash for Total Metals

As > 2.1 mg/kg

Colored Not Colored

As < 2.1 mg/kg As > 2.1 mg/kg As < 2.1 mg/kg

Results: Ash for Total MetalsResults: Ash for Total Metals

XXXX

Fraction of Samples in Category with Values Greater Than Indicated Category

Copper vs. ChromiumCopper vs. Chromium

y = 1.96x - 3.95

R2 = 0.955

0

100

200

300

400

500

600

0 100 200 300 400 500

Copper (mg/kg)

Ch

rom

ium

(m

g/k

g)

5% CCA Control

Type A CCA

Type C CCA

Type B CCA

Type C MinType C MaxBest Fit Line for Mulch Data, Overlaps Theoretical "Type C" Maximum Line

Orlando

JacksonvilleTallahasseePensacola

Gainesville

Tampa

Fort Myers

St. Pete

Marathon

Key Largo

Lake Worth

South Florida

Legend

Arsenic <0.07 – 2.1 mg/kg

Arsenic 3.7 – 50 mg/kg

Arsenic 50 – 100 mg/kg

Arsenic greater than 100 mg/kg

Sebastian

Brandon

City Location

Colored

Non-Colored

SPLP ResultsSPLP Results

Methods: SPLP AnalysisMethods: SPLP Analysis

SPLP Samples: 84

44

31 13 2 38

40

Mulch SPLP ResultsMulch SPLP Results

Positive for As

Colored Not Colored

Not Positive for As Positive for As Not Positive for As

SPLP TableSPLP Table

XX

X X

Orlando

JacksonvilleTallahasseePensacola

Gainesville

Tampa

Fort Myers

St. Pete

Marathon

Key Largo

Lake Worth

South Florida

Legend

Arsenic below detection limit

Arsenic 12–20 ug/L

Arsenic 21-50 ug/L

Arsenic greater than 51 ug/L

Sebastian

Brandon

City Location

Colored

Not Colored

XRF AnalysisXRF Analysis

ResultsResults

Fraction of positive hits of As with XRF

0 to 0.2 >0.2 to 0.5 >0.5 to 1

> 75 1 1 6

> 25 - 75

2 3 0

To

tal

Re

co

ve

rab

le

As

(m

g/k

g)

0 - 25 66 4 0

ConclusionConclusion 52% are colored mulches

12% colored mulches positive for arsenic 17% mulches contained plywood

67% mulches with plywood positive for arsenic 87% mulches with plywood were colored

73 % of colored mulches with plywood contained arsenic 44 % of South Florida samples detected positive for

arsenic in SPLP analysis 75 % of open bin mulches contained high

concentrations of arsenic

52% are colored mulches 12% colored mulches positive for arsenic

17% mulches contained plywood 67% mulches with plywood positive for arsenic

87% mulches with plywood were colored 73 % of colored mulches with plywood contained arsenic

44 % of South Florida samples detected positive for arsenic in SPLP analysis

75 % of open bin mulches contained high concentrations of arsenic

ConclusionConclusion

Engineered wood was found in 21% of consumer mulches

Arsenic was found in 28% consumer mulches

SPLP tested showed that arsenic leached from 27 % of consumer mulches 48% of these samples leached over 50 μg/L

XRF is capable of spotting arsenic in mulch, especially mulch with higher concentrations

Engineered wood was found in 21% of consumer mulches

Arsenic was found in 28% consumer mulches

SPLP tested showed that arsenic leached from 27 % of consumer mulches 48% of these samples leached over 50 μg/L

XRF is capable of spotting arsenic in mulch, especially mulch with higher concentrations

QuestionsQuestions

Draft Report on-line at www.ccaresearch.org

under the “publications” link

Comments accepted on report until August 30th

Draft Report on-line at www.ccaresearch.org

under the “publications” link

Comments accepted on report until August 30th