prepared by: gary jacobi extent of cca treated wood in consumer mulches and methods of detection
TRANSCRIPT
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