Consumer products and packaging ranging from newspapers to cereal boxes contain a category of toxic chemicals known as polychlorinated biphenyls (PCBs), according to a report released Aug. 7 by the Washington State Department of Ecology. The chemicals were banned 35 years ago and are no longer used in manufacturing, but are still generated as a byproduct of certain chemical processes. They pose a variety of human health risks, including cancer and developmental problems.

What Are PCBs and Why Are They Dangerous?

PCBs were manufactured by combining a substance known as biphenyl with chlorine and used in a variety of products. The most common use was in electrical transformers because the compound is both flame retardant and does not conduct electricity. However, evidence of PCBs’ toxicity and tendency to accumulate in the environment led to their ban in 1979 under the Toxic Substances Control Act (TSCA).

PCBs belong to a particularly harmful group of chemicals known as PBTs, meaning they are “persistent, bioaccumulative, and toxic.” These are toxic chemicals that do not easily break down in nature and therefore accumulate in plants and animals. People can be exposed to PCBs through food such as fish and dairy, by swimming in contaminated waters, and through indoor air pollution, especially in buildings using older transformers.

Exposure to PCBs at high levels is linked to a number of health concerns including cancer, endocrine disruption, and weakened immune systems. Infants can also be exposed to PCBs in their mother’s womb or through breast milk, causing problems such as low birth weight and decreased motor skills.

Despite their ban, PCBs persist in the environment due to prior manufacturing and current industrial processes that unintentionally create the toxins. Nearly all of Washington State’s waterways have tested positive for PCBs, sometimes above acceptable levels. This prompted Washington’s Department of Ecology to examine what products may be contributing to its continued release.

The Washington State Department of Ecology Report

Recent studies point to pigments and dyes as a contemporary source of PCBs. Thus, the Washington State Department of Ecology study focused on 68 consumer products using pigments in order to assess whether PCBs were present. These included a range of everyday products such as packaging materials, paints, and paper products.

Researchers detected PCBs in 72 percent of tested products in concentrations ranging from one to 45 parts per billion (or ppb, which is roughly equal to one drop of water in an Olympic size swimming pool). All paper products had traces of PCBs, as well as most food product packaging and most paints. These include ordinary products handled by both children and adults, such as printed newspapers and fruit snack packages. Caulks were the only products to show relatively low or undetectable levels of PCBs.

Based on these findings, the report concludes:

  1. PCBs are present in everyday consumer products
  2. PCBs leach into the environment through both water and air
  3. People may be exposed to PCBs through direct contact with consumer products.

The report does not include a risk assessment of PCBs, nor does it further discuss exposure routes. It does, however, point to the importance of testing additional products such as cosmetics and clothing.

Regulating an "Incidental" Chemical

When the U.S. Environmental Protection Agency (EPA) banned PCB production in the late 1970s, scientists already knew the compound could be inadvertently created through pigment and dye manufacturing. In the early 1980s, EPA exempted unintentionally created PCBs that occurred at levels less than 50 parts per million (or ppm, which is equal to one drop of water in a 50 liter barrel). The products sampled by the Washington State Department of Ecology fall far below this threshold and are not subject to regulation.

However, even if PCB levels are too low to cause direct effects, the chemical can still enter the environment, accumulating in water, soil, and throughout the food chain at levels high enough to pose a health risk.

Moreover, the EPA acknowledges that this 50 ppm threshold was based on economic concerns and does not take exposure or health risks into consideration. EPA has been reviewing its PCB regulations since 2009, including the current limit for unintentionally manufactured PCBs. The agency issued an advanced notice of proposed rulemaking in 2010 but to date has not released any proposed rules.

Conclusion

States like Washington are working to clean up waterways contaminated by PCBs and to educate the public about the risk of exposure. However, as EPA continues to delay updating PCB regulation, these toxic chemicals continue to be released into the environment in hazardous amounts.

Reducing the release of PCBs in the environment is the best way to prevent future contamination, avoid accumulation in the food chain, and reduce health risks to people. EPA must move forward with updating its PCB standards so it can safeguard communities and the environment from these dangerous toxins.

(Visited 81 times, 1 visits today)