Testing for heavy metals in food packaging
EDF’s detailed recommendations on testing for heavy metals in food packaging
Companies should periodically test all food packaging that contacts food anywhere along the supply chain for arsenic, cadmium, or lead to identify potential contamination. You should investigate levels over 10 parts per million (ppm) for any one of the heavy metals, and stop using any packaging where an ink, adhesive, or other component has a combined heavy metal concentration of more than 100 ppm.
We recommend that companies use a CPSC-accepted, third-party certified labs that evaluate children’s products for lead consistent with CPSC’s methods CPSC-CF-E1001-08.3 (for metals) and E1002-08.3 (for non-metals). While we recognize that packaging is not a children’s product, the CPSC and third-party oversight for children’s products provide us with greater confidence in the analysis in the absence of similar oversight specific to packaging. Note that while the testing is focused on lead, the methods cover arsenic and cadmium as well.
Following these recommendations will help reduce the risk of contaminating food as well as the recycling and composting streams. It will also help verify compliance with state laws (see the Toxics Packaging Clearinghouse for details).
Methods to measure heavy metals in food contact materials
CPSC has approved two methods: CPSC-CF-E1001-08.3 for metals and CPSC-CF-E1002-08.3 for non-metals to evaluate lead in children’s products to ensure compliance with the 100 ppm limit in the agency’s rules. From our experience, the methods allow for measurements down to 10 ppm.
The CPSC methods allow for various destructive testing techniques, but, as a practical matter, x-ray fluorescence (XRF) is the most popular one because it is fast and does not destroy the samples. Because of the potential variability of the metal content in a substrate, CPSC only allows an XRF if the lead levels are measured below 70 ppm.
The Toxics Packaging Clearinghouse encourages the use of XRF to assess compliance with its 100 ppm limit on total chromium, cadmium, lead and mercury. The Clearinghouse found that the technologies requiring a sample to be digested can underestimate the heavy metal content because the plastics do not consistently dissolve.
Examples of laboratories marketing heavy metal testing in food contact-like materials
CPSC requires that labs evaluating children’s products for compliance with the lead testing limit must be third-party certified and accepted by the agency. The agency provides a search tool at https://www.cpsc.gov/cgi-bin/labsearch/ that companies can use to find an accepted lab. On the webpage, select one or both of the methods described above from the options under “testing scope” and submit the request. You can narrow the search by lab name, lab ID, country, state or city. We used the tool and found more than 400 labs.