The U.S. can claim two dubious distinctions when it comes to highly hazardous polychlorinated biphenyls (PCBs)—not only was it the world’s top producer and user of the chemicals, but when it comes to cleaning up its mess, our new analysis finds that the U.S. is far behind other higher-income countries. In the last 10 years, while Canada and Czechia (Czech Republic) destroyed 99% of their PCB stocks, the U.S. has only decreased its stocks by 3%.
PCBs: still a problem
While the production of PCBs generally ceased almost 40 years ago, we found that more than 10 million tonnes of PCB-containing materials still remain around the globe. These large remaining stocks are a global concern because PCBs are persistent, bioaccumulative, and toxic (PBT) chemicals, also known as persistent organic pollutants (POPs).
PCBs are persistent- they don’t break down in the environment and can easily move around the globe, concentrating in the polar regions. As such, PCBs are found in the high Arctic and Antarctic, far from production and use locations. The bioaccumulation of PCBs means that the chemicals build up in animals and people, becoming more concentrated as they move up the food chain. High levels are found in top predators like killer whales and threaten their survival. Finally, PCBs are toxic, with numerous health hazards, including cancer, reproductive toxicity, developmental neurotoxicity, and immune toxicity.
This trifecta of troubling properties means that PCBs, along with other POP chemicals, are extremely difficult to control. Once produced, these chemicals spread far and wide, magnify in food webs (including in people and our food supply), and contribute to health harms. If one country uses POP chemicals, it can affect the entire globe—so addressing the world-wide threats of POPs requires global cooperation.
The Stockholm Convention on Persistent Organic Pollutants
The Stockholm Convention on Persistent Organic Pollutants is a global treaty aiming to protect people and the environment from POPs by requiring parties to limit the release of these chemicals. The treaty includes 184 countries and the European Union, but the U.S. is not a signatory.
The Stockholm Convention requires parties to achieve environmentally sound management of PCBs (destruction without the production of other contaminants in the process and so that the PCBs don’t leak into the environment) by 2028. According to our analysis, 30% of signatories are on track to meet this target as of 2021, including Canada and Czechia.
U.S.: big production, slow reduction
As noted above, the U.S. led the world in PCB production and use, with Monsanto producing more than 50% of all global PCBs. Despite having a big problem to deal with, the U.S. stood out amongst high-income countries for 1) lacking regulatory deadlines to phase out use of PCBs and to eliminate PCB stocks, and 2) having an incomplete and fragmented inventory of PCB-containing materials and their disposal. These weaknesses have contributed to the United States’ dismal progress on eliminating PCB stocks (i.e., 3% compared to 99% over a similar time period in Canada and Czechia).
Unfortunately, because they are POPs that can spread around the globe, the remaining PCB stocks in the U.S. and their improper management is now everyone’s problem.
Lessons learned: other chemicals, other treaties
As work to create an international, legally binding agreement to end plastic pollution gets underway, it is useful to look at the relevant lessons learned from our analysis.
Comprehensive information on any materials and substances to be managed is key—because you can’t manage what you don’t know about. We found that 42% of Stockholm Convention signatories didn’t have a handle on the amounts or whereabouts of PCBs in their country, hampering their ability to eliminate stocks.
Low-income countries must manage PCBs, most of which have originated from high income countries exporting their hazardous waste as a cheap method of “waste management.” These low-income countries need financial, administrative, and political support to implement treaty obligations, as these resources are generally lacking. Strategies such as funding specific initiatives for PCBs through the Global Environment Fund have had limited success, but far higher levels of global investments are needed to meet the significant challenges in less wealthy nations, especially as these countries often bear the brunt of myriad pollutants generated by high-income countries, including PCBs and plastics.
Last, as the saying goes, an ounce of prevention is worth a pound of cure. Our analysis finds that decades after production stopped, we are far from eliminating the threats of PCBs. This highlights that limiting production and use of current POPs like PFAS should be an urgent priority for chemicals management policies globally. Countries should curtail potential POPs at the stage of chemical manufacturing– because the best management strategy for POPs is to not make POPs in the first place.
My co-authors on this paper are Lisa Melymuk, Jonathan Blumenthal, Ondrej Sanka, Adriana Shu-Yin, Katerina Sebkova, Kristi Pullen Fedinick, and Miriam Diamond.