PCB in the USA: According to the study, banned chemical continues to be produced on a large scale

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Mackerel (symbolic image): PCBs can be absorbed into the body through contaminated foods

Photo: Ross Woodhall / Image Source / Getty Images

PCB chemicals have actually been banned for decades, including in Germany.

But according to a study, the industry continues to produce them on a large scale - as a common by-product.

The researchers therefore appeal to consider PCBs as an emerging pollutant.

The study was published in the journal “Science of The Total Environment”, and was first reported by the “Guardian”.

Polychlorinated biphenyls - PCBs - were used as plasticizers in paints, sealants or insulating agents.

PCBs have been banned in Germany since 1989, and in the USA for a decade longer.

PCBs can still be released as a byproduct.

The chemicals accumulate in the environment over many years and are considered harmful to health.

Among other things, they are suspected of being carcinogenic.

Often not recorded in studies

The research team led by David Megson from Manchester Metropolitan University estimates that significantly more PCBs are currently being produced in the USA than during the peak of commercial production in the 1970s.

While around 39,000 tons of PCBs were said to have been produced in the USA alone in 2019, it is now 45,000 tons per year.

However, these PCBs are not detected in most studies, the group writes.

As Megson explains in the Guardian, this is because the chemicals created as an unintended byproduct are different from those commercial PCBs from the last century.

Therefore, they would potentially pose a growing, uncontrolled risk to the environment and human health.

"Most people associate the accidental production of PCBs with paints and pigments, but our research shows it is a much broader spectrum," Megson told the Guardian.

For example, chlorinated solvents used in the chemical industry are an important source, according to the study.

According to the report, the U.S. Environmental Protection Agency (EPA) stated that its "regulations allow unintentionally generated PCBs at low, specified concentrations and under certain conditions."

Companies that unintentionally produce or import PCBs are obliged to report this activity and record the respective quantities.

The EPA cannot comment on the specific quantities from the investigation.

But when the regulations came into force, it was estimated that less than 4,989 kilograms of unintentionally generated PCBs were entering products each year, and of that amount, less than about 450 kilograms per year were likely entering the environment.

In Germany, the Federal Environment Agency assumes that 221 kilograms of PCBs were created as a byproduct in 2021 and writes that the remaining emissions from ongoing applications are “only estimated to be low.”

People ingest PCBs, for example, by eating contaminated fish.

The proportion of PCBs increases with the fat content of the animals; fatty fish such as mackerel, salmon and halibut have the highest levels - which, according to German authorities, are still well below the permissible limits.

Detected in killer whales

"The assumption made in the study that around 43,000 tons of PCBs were legally produced in the USA in 2019 could be correct despite all the uncertainties," said Lee Bell from the NGO International Pollutants Elimination Network to the Guardian.

He was a member of the PCB expert group of the Stockholm Convention, an agreement on binding bans and restrictions under international law for certain persistent organic pollutants.

"On a global scale, current unintentional PCB production could be much higher and needs to be urgently investigated."

The chemical can also be problematic for animals - it has already been found in high concentrations in marine mammals.

"We have seen the impact of PCBs in the British killer whale population, which is heading for complete collapse within the next hundred years due to heavy PCB pollution," said Francesca Ginley of the Marine Conservation Society, according to the report.

According to her, a killer whale on the west coast of Scotland was found dead in 2016 after becoming entangled in fishing nets.

An autopsy revealed that the PCB concentration in his tissue was 100 times higher than levels known to affect the health of marine mammals.

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