After a fresh produce company was informed that the ink on its plastic bags contained lead well above the limit set by state laws, it turned away 15 container loads of packaging being sent from overseas and sought out a new supplier.
The testing was done by the Toxics in Packaging Clearinghouse (TPCH), and while the produce company was able to confirm the group's findings, which were reported in 2009, other companies with packaging that violated state laws replied with certificates from testing laboratories that showed they were in compliance.
This kind of finding means that even if you're doing your due diligence, you could still end up on the wrong side of regulations. But the TPCH is working to bring more assurance to the process and educate testers and the companies using them about what they can do to guarantee their results are as accurate as possible.
Patricia Dillon, program manager for the TPCH, said when the group began testing packaging on store shelves five years ago, they kept running into companies with lab results that were contradictory to the TPCH's own findings.
"We just got too many results that said the packaging was clean," she said.
The problem, she said, was that some labs were missing some of the lead and cadmium present in materials due to the test processes they used. In the last couple of years, labs have gotten better with their processes, Dillon said, but problems remain.
The TPCH recently had seven labs test eight packaging samples that it knew the lead and cadmium content of. Nine of the 56 results [PDF] were considered unacceptable, meaning the labs underreported the amount of lead or cadmium by more than 25 percent below the average result. And one resulted in a false negative: The lab said the packaging complied with state law when in fact it did not.
If a company put that packaging on store shelves, and a state found it violated the law, no certificate of compliance from a testing lab would shield it from having to pull those products from the market.
Nineteen states have laws that restrict the amount of lead, cadmium, mercury and chromium in packaging to 100 parts per million combined. Those states include California, Connecticut, Florida, Georgia, Illinois, Iowa, Maine, Maryland, Minnesota, Missouri, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, Virginia, Washington and Wisconsin.
Aside from California, whose law was passed in 2003, all the laws predate 1995. "These laws are all about reducing the amount of heavy metals that go into the waste stream, because heavy metals do not disappear," Dillon said. "Packaging is very short-lived, there is lots of it, and it very quickly goes from the retail shelf to the trash can."
The TPCH has brought attention to toxics in packaging through the use of x-ray fluorescent (XRF) analysis -- a quick and relatively inexpensive procedure in which an XRF device emits radiation at a material to determine its elemental composition -- which it began using about five years ago.
"We thought most packaging was free of heavy metals because the laws had been in effect for so long, but when we started to screen we found that was not the case," Dillon said. Studies released in 2007 and 2009 [PDF] showed that 16 percent and 14 percent, respectively, of screened packages exceeded state laws.
Two types of packaging in particular stood out: flexible PVC (used for comforters, bed sheets, toys) and inks or colorants on plastic bags. What also stood out was how often companies said their packaging had been tested by labs and had certificates showing the packaging was in compliance with laws.
The results of the recent lab survey, though, were better than expected, Dillon said. As noted, only one of the 56 results would have told a company its packaging was legal when it really wasn't.
Dillon said some of that success could be due to the Consumer Product Safety Improvement Act, which went into effect in early 2009, setting new standards for lead in children's toys. It also required tests to be based on the total concentration of metals in toys, not just how much could leach out.
And most differences between the TPCH's screenings and the lab results, Dillon said, are likely due to testing methods used by labs.
"If you dont prepare the sample correctly, you won't detect the metals," she said.
Specifically, the problem arises when labs do not completely dissolve the samples they are testing. Labs test what is in packaging by dissolving it and then measuring what is left in the solution. If the sample is not completely dissolved, not all of the metal in it might be in the solution.
The TPCH recommends [PDF] that companies affected by the state packaging laws ask their testing labs to note how much of their samples were dissolved during testing, and to repeat any tests in which metals were found and the samples were not completely dissolved.
Toxic image CC-licensed by eek the cat/Flickr