Industry may be producing more carcinogenic PCB chemicals today than at any point in history, even though their production was banned more than 40 years ago.
PCBs (polychlorinated biphenyls) are man-made substances that were used as coolants and lubricants in electrical equipment until they were banned due to their association with health problems and because they do not easily break down in the environment.
They are known to cause cancer in animals as well as damage the immune, reproductive, nervous, and endocrine systems. They may also be carcinogenic to humans, and exposure to them has been associated with skin conditions such as acne in adults and neurobehavioral and immunological changes in children.
Research confirmed by The Guardian and Watershed Research shows that PCBs are produced as a by-product of chemical reactions, meaning that small amounts of PCBs are present in many chemicals used today. means.
“This is surprising given that the manufacture of PCBs has been banned for more than 40 years and PCBs are to be eliminated under the Stockholm Convention,” said Manchester, which conducted the study. said Dr. Dave Megson, an environmental forensic scientist at Metropolitan University. study.
“When you consider the amount of these chemicals and the trace amounts of PCBs they contain, this is a huge number. About 45,000 tons per year in the United States alone.” At the peak of commercial production in the 1970s, About 39,000 tonnes were produced each year, the study said.
“Most people associate this incidental production of PCBs with paints and pigments, but our research shows it’s much broader than that,” Megson said. According to his research, chlorinated solvents used in the manufacture of chemicals are the main source.
“Currently, PCBs are not detected in many studies because the specific PCBs produced by chance are different from the PCBs produced intentionally in commercial mixtures more than 50 years ago.”
The study states that these types of byproduct PCBs are not measured in many existing monitoring programs and could pose “unmonitored and growing environmental and human health risks.” The report states that they should be classified as “contaminants of emerging concern” and are urgent because all PCBs, not just traditional PCBs from commercial mixtures, are considered toxic. This suggests that there is a need to address this.
Lee Bell of the International Network of Chemical NGOs, also a member of the PCB expert group at the Stockholm conference, said: In the case of intentional PCB manufacturing, parties to the convention have a deadline of 2028 to destroy all stockpiles of old PCBs. Parties are woefully behind in this task, with approximately 80% of PCB stockpiles still not destroyed.
“The study’s assumption that approximately 43,000 tons of PCBs could have been legally produced in the United States in 2019 is likely true, despite the uncertainties. This would exceed the 1970 US peak production of 39,000 tons.On a global scale, current unintentional PCB production could be even higher and warrants urgent investigation.”
Bell says there needs to be stricter limits on the release of traditional PCBs and by-product PCBs into water. “It is unfortunate that hundreds of millions of dollars are being spent destroying legacy PCBs while regulators allow unintentional PCB contamination to spread virtually unabated.”
PCBs have been detected at high levels in marine mammals and have been a long-standing concern for Dr. Francesca Ginley of the Marine Conservation Society. “PCBs are persistent chemicals. They persist for decades, accumulate in the environment, and bioaccumulate in the body. marine mammals.
“We are witnessing the impact of PCBs on the UK’s killer whale population, which is heading for complete collapse within the next 100 years, consistent with severe PCB contamination. Killer whales on the west coast of Scotland were caught in fishing nets in 2016. “It was found entangled and dead, and post-mortem examination revealed that the PCB levels in its tissues were 100 times higher than levels known to affect the health of marine mammals.” Ginray.
A study last year by the Zoological Society of London and the University of Glasgow found that killer whales stranded in the UK were 30 times over the toxic threshold for PCBs. It warned that the chemicals “could wipe out the killer whales.”
The manufacture of PCBs was banned in the United States in 1979 and in the United Kingdom in 1981, and efforts continue in the United Kingdom to restrict their use in electrical equipment. Sources of legacy contamination from commercially manufactured PCBs include materials in landfills and buildings.
A Defra spokesperson did not comment on the production of PCBs as a by-product, but said: “We aim to eliminate the use of PCBs by 2025 in our environmental remediation plan and are committed to working with industry to register all equipment and ban their use.” that contain chemicals.
“We have also been consulting on proposals to amend the PCB Regulations to ensure we deliver on our commitments. [under the international Stockholm convention] As well as providing clarity to industries and companies. The response to our consultation and next steps will be published in due course. ”
The U.S. Environmental Protection Agency (EPA) states that “its regulations permit inadvertently produced PCBs at defined low concentrations and under certain conditions. Facilities that produce or import PCBs must report this activity to EPA and maintain records regarding PCBs, including the levels of PCBs produced and released.”
The U.S. Environmental Protection Agency said it could not comment on Megson’s findings, but said information available at the time the rule went into effect showed that “less than 11,000 pounds (4,989 kg) of inadvertently produced PCBs enter products annually. It is estimated that less than 1,000 pounds per year can enter the environment.”
Last month, EPA received a petition from the Washington State Department of Ecology regarding the issue of inadvertently produced PCBs. The report calls on the EPA to “initiate rulemaking to protect public health from PCBs in consumer products.” EPA has until April 3, 2024 to approve or deny the petition.
“If PCBs continue to be released, the problem will only get worse,” Ginley said. “They’re not just causing a temporary problem. They’re affecting entire generations of animals. This is not just for killer whales; PCBs are thought to be associated with increased mortality and reduced testicular weight from infectious diseases in UK porpoises. We should learn from the harm, apply it to other persistent chemicals, and not keep making the same mistakes.”
