Last week I posted a short story from our sister publication, Plastics & Rubber Weekly, about a pair of scientists who want governments around the world to classify certain kinds of plastic waste as "hazardous." I thought that would be the end of the discussion.
But the debate is continuing to get attention, so let's take a closer look.
As the first story noted, the issue was raised in a "Comment" column in the periodical Nature: "Classify plastic waste as hazardous." Two California-based graduate students -- Chelsea Rochman and Mark Anthony Browne -- claim that labeling some plastics -– specifically PVC, polystyrene, polyurethane and polycarbonate -- as hazardous would cut health risks and protect wildlife. ("Pair urges government to classify some plastic waste as hazardous.")
The pair wrote: "We believe that if countries classified the most harmful plastics as hazardous, their environmental agencies would have the power to restore affected habitats and prevent more dangerous debris from accumulating. Ultimately, such a move could boost research on new polymers and replace the most problematic materials with safer ones."
They write later in the article: "We feel that the physical dangers of plastic debris are well enough established, and the suggestions of the chemical dangers sufficiently worrying, that the biggest producers of plastic waste -- the United States, Europe and China -- must act now. These countries should agree to classify as hazardous the most harmful plastics, including those that cannot be reused or recycled because they lack durability or contain mixtures of materials that cannot be separated."
The precautionary principle is a key part of their point. According to the article, "We believe that manufacturers of plastic, along with the food and textile industries that rely heavily on it, should have to prove that their products and packaging are safe."
I sympathize with the authors' concern about plastic marine debris -- this is a real problem that the global plastics industry was slow to address, but now is finally starting to take action. But the idea that the answer to the problem is to declare large segments of the plastic industry "hazardous" is an extreme and unreasonable approach.
First, the safety of PVC, polystyrene, polyurethane and polycarbonate have been investigated for years. While the fine details may be debated, and some materials are not appropriate in certain applications, the government agencies charged with deciding chemical safety have largely determined that these plastics are not "hazardous."
Second, I don't anticipate that governments will be eager to take on all the legal and regulatory burdens that would result from such a determination. Better to let them focus on materials that clearly are dangerous, rather than keeping them busy with lesser threats.
American Chemistry Council reaction
Steve Russell, vice president of plastics for the American Chemistry Council, issued a statement on the Nature commentary that's worth sharing:
"America's plastics makers agree that litter doesn't belong in our oceans, waterways or any part of our natural environment. And, the global plastics industry has organized to combat the problem, sponsoring research and working in public-private partnerships. But the suggestions by the commenters in the journal Nature are neither justified nor helpful.
"We agree that marine debris deserves serious attention; but it also deserves serious debate. The suggestion to classify plastic as hazardous waste does not reach that mark. ... Plastics used in food contact and medical device applications are evaluated for safety by governments around the world. And the plastics identified by the authors as 'higher priorities' are used in durable applications (pipes, siding, roofing, refrigerators) which are not generally littered or found in the ocean.
"Scientists have long understood that persistent organic pollutants (POPs) can bind to organic compounds, such as plastics; what is currently not known is whether pollutants bound to plastics are then bioavailable or a significant route for exposure to marine life. For example, NOAA has stated that 'POPs have a high affinity for plastic in seawater. This is the basis for several POP sampling techniques, including passive sampling. While this high affinity results in elevated POP concentrations on microplastic particles, these POPs may not be readily bioavailable.'
"America's plastics makers agree more research is needed on this subject, and we are supporting a comprehensive scientific review of this issue by the Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP)working with international agencies and NOAA."
Should common plastics be labeled toxic?
For the last word today -- or, if you're so inclined, an opportunity to jump into the debate -- check out The New York Times' Rendezvous blog, which asked readers "Should common plastics be labeled toxic?"
So far 14 readers have weighed in, with the majority in favor of the proposal. Not a scientific sample, to be sure, but evidence that the public image of plastics is not nearly as high as many in the industry would like.