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Interlaboratory Study 2009

We are pleased to announce that we participated in an international, interlaboratory study on metals in plastics during September 2009.  The study was conducted by the Institute for Interlaboratory Studies (Dordrecht, NLD).  

The study consisted of 2 commercial samples of polypropylene and polyethylene plastic with varying amounts of chromium (Cr), hexavalent Cr, cadmium (Cd), lead (Pb) and mercury (Hg).  As in past studies, our results were in excellent agreement with the study means.

 

In this study 106 laboratories from 29 countries participated, 7 from the US.  Since we routinely test for Prop 65 and environmental regulations in many products, especially lead (Pb), cadmium (Cd), and other toxic, heavy metals, we routinely participate this study.  

While the entire report can be viewed at http://www.iisnl.com/pdf/iis09P02X.pdf, the results are summarized below.  Note that there are two columns with our results.  These samples were tested using both ICPMS as well as XRF.  XRF is a much less sensitive technique which we often use to screen samples for high levels.

For a quotation...

Lead (Pb) Results
mg/kg

Sample

 Study
Mean 		WCAS ICPMS Z
0950 268 244 -0.96
0951 271 262 -0.38

Cadmium (Cd) Results
mg/kg

Sample

 Study
Mean 		WCAS ICPMS WCAS XRF
0950 37.9 35.0 42
0951 (3.96) 3.71 3.4

Chromium (Cr) Results
mg/kg

Sample

 Study
Mean 		WCAS ICPMS WCAS XRF
0950 67.5 64.2 68
0951 36.7 35.9 28

 

Hexavalent Cr Results
mg/kg

Sample

 Study
Mean 		Std Dev WCAS total
0950 8.49 15 6.2
0951 10.3 7.5 9.0

The total Cr(VI) was determined on a sample which was pulverized to a fine powder using a freezer mill. 

 

Mercuryr Results
mg/kg

Sample

 Study
Mean 		Std Dev WCAS ICPMS
0950 2.67 0.99 3.6
0951 2.26 1.0 1.6

Interlaboratory Study 2008

We are pleased to announce that we participated in an international, interlaboratory study on metals in plastics during September 2008.  The study was conducted by the Institute for Interlaboratory Studies (Dordrecht, NLD).  

The study consisted of 2 commercial samples of polypropylene plastic with varying amounts of chromium (Cr), hexavalent Cr, cadmium (Cd), and lead (Pb).  As in past studies, our results were in excellent agreement with the study means.

In this study 99 laboratories from 32 countries participated, 4 from the US.  Since we routinely test for Prop 65 and environmental regulations in many products, especially lead (Pb), cadmium (Cd), and other toxic, heavy metals, we were quite interested in participating in this study.  

While the entire report can be viewed at http://www.iisnl.com/pdf/iis08p02x.pdf, the results are summarized below.  Note that there are two columns with our results.  These samples were tested using both ICPMS as well as XRF.  XRF is a much less sensitive technique which we often use to screen samples for high levels.

Previous Studies

To view previous results:

Cd in PVC 2001
Cd and Pb in PVC 2003

For more information on testing for trace elements, click on ICPMS, XRF, or Cr(VI).

For a quotation...

Lead (Pb) Results
mg/kg

Sample

 Study
Mean 		WCAS ICPMS WCAS XRF
0950 <5 <0.07 <10
0951 94.7 94.6 81

Cadmium (Cd) Results
mg/kg

Sample

 Study
Mean 		WCAS ICPMS WCAS XRF
0950 <5 0.06 <10
0951 94.9 94.9 79

Chromium (Cr) Results
mg/kg

Sample

 Study
Mean 		WCAS ICPMS WCAS XRF
0950 195 138 150
0951 <5 0.78 <10

The study mean for XRF results only was 162 mg/kg. 

Hexavalent Cr Results
mg/kg

Sample

 Study
Mean 		WCAS total WCAS surface
0950 * 66 4
0951 <2 <0.2 <0.02

* Study results varied from 0-200 mg/kg.  Our results fell into a group whose mean was 60.5 mg/kg.  The total Cr(VI) was determined on a sample which was pulverized to a fine powder using a freezer mill.  The surface contamination was determined on 1-3 mm pieces.  In both cases Cr(VI) was determined by EPA 3060A/7199.

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Exova

Formerly West Coast Analytical Service (WCAS) and Bodycote Testing Group