Over the past four months, EPA issued proposed rulemakings under the Toxic Substances Control Act (TSCA) that relied on scientific methods that fail to protect susceptible subgroups from harmful toxic chemical exposures. Using methods developed by the World Health Organization (WHO), scientists at PRHE estimated that workers and fenceline community residents — groups that are both more exposed and more susceptible to harm from toxic chemical exposures — actually face risk levels up to 5,000 times higher than what EPA often considers as a health protective benchmark for four highly toxic chemicals: methylene chloride, perchloroethylene, carbon tetrachloride, and 1,4-dioxane.
These chemicals, which are linked to cancer, liver toxicity, reproductive toxicity, neurological harm, and even death (see Table 1), are among the first chemicals for which EPA has proposed risk management rules under the amended TSCA to restrict or prohibit chemical use.
TSCA was designed to protect human health
EPA’s recent rulemakings underscore a decades-long pattern of failing to protect people and the environment from harmful chemical exposures, especially children, workers, and fenceline community residents who face the greatest risks and health harms.
Every year, hundreds of thousands of workers manufacture billions of pounds of toxic chemicals in the U.S. and residents of communities near facilities that release these chemicals — also known as fenceline communities — are exposed to millions of pounds of chemical releases. Moreover, communities living in proximity to polluting facilities are more likely to be low-wealth, communities of color that are more susceptible to harm due to multiple compounding non-chemical stressors, like food and housing insecurity, racism, and discrimination.
TSCA, as amended in 2016 by the Frank R. Lautenberg Chemical Safety for the 21st Century Act, was intended to offer stronger protections for children, pregnant people, workers and fenceline community residents. The amended TSCA specifically includes language requiring EPA to evaluate the risk posed by toxic chemicals to “potentially exposed or susceptible subpopulations” and issue risk management rules that eliminate any unreasonable risk to these groups to protect human health.
The four recent rulemakings, however, fail to do so. EPA found that all four chemicals present unreasonable risk to human health, but failed to evaluate the full extent of those risks or provide adequate mitigation strategies that would eliminate those risks.
EPA’s math doesn’t add up
According to EPA, an acceptable risk level, or likelihood of developing disease, falls anywhere between 1-in-10,000 and 1-in-1,000,000, with the low end of the range being the commonly used target risk level in many EPA policies. However, as demonstrated in the four recent rulemakings, EPA only estimates risk likelihood when evaluating the risk of developing cancer and uses a method that is not scientifically appropriate when evaluating potential risks of non-cancer related diseases from toxic chemical exposures.
Scientists at PRHE estimated the likelihood of developing non-cancer health harms for the four TSCA chemicals using a method developed by WHO, and the findings are staggering. For example, the likelihood of developing a loss of visual memory function — an outcome seen in patients with Parkinson’s Disease — as a result of workplace exposures to perchloroethylene was as high as 1-in-200, a risk level nearly 5,000 times higher than the 1-in-1,000,000 risk level that EPA frequently considers health protective (see Table 2). Even more troubling is that this risk level is associated with workplace perchloroethylene exposures that EPA considers safe and allowable under its recent proposed risk management rule.
EPA is underestimating risk to fenceline communities
For all four chemicals, EPA also relied on a screening methodology to examine risks to fenceline communities that has previously been criticized as being inadequate by scientific experts and community stakeholders. Among myriad flaws, this methodology failed to: 1) consider chemical releases from more than one facility at a time; 2) aggregate exposures from more than one exposure route or pathway (for example, adding together air and drinking water exposures); and 3) examine the impact of non-chemical stressors on human health risk. Collectively, these omissions underestimate risk for fenceline communities, which tend to be low-wealth communities of color facing multiple chemical and non-chemical stressors and living in proximity to clusters of polluting facilities.
Despite the flawed screening methodology, EPA still found unacceptable risks to fenceline communities and failed to propose any measures to address or manage those risks. Moreover, the risks EPA identified fell disproportionately on low-wealth communities of color. For example, in its proposed risk management rule for carbon tetrachloride, EPA found cancer risk levels for some fenceline communities exceeded 1-in-10,000 (which is typically the upper bound of what EPA considers acceptable) as a result of ambient air exposure — and these estimates don’t even consider the risks of non-cancer related health effects, which could substantially increase risk levels. EPA itself acknowledged that the communities within 1 mile of carbon tetrachloride-releasing facilities, which were concentrated in Texas and Louisiana, were predominantly communities of color with nearly a quarter of the population living below the poverty line. And yet, EPA failed to provide mitigation strategies that would eliminate that risk — which includes prohibition of use.
EPA must do better to regulate toxic chemicals
A failure to address and eliminate risk to susceptible subpopulations, like fenceline communities, is not only a violation of TSCA, but also can perpetuate exposures in part due to systemic racism that contributed to these environmental injustices (for example, from historical redlining). It is EPA’s duty to protect human and environmental health and eliminate the health risks associated with toxic chemical exposures. The amended TSCA provides EPA with the opportunity to issue health protective rulemakings that utilize the best available scientific methods and protect susceptible subpopulations from the harms of toxic chemical exposures. This first round of risk management regulations under the revised TSCA have failed to do so, perpetuating a flawed and inadequate chemical regulatory system.
Prohibiting all uses of these four chemicals will ensure that fenceline communities and the public will not be exposed to harmful levels of these pollutants and contribute to healthier workers and communities.
About the author
Rashmi Joglekar, PhD is the Associate Director of Science, Policy, and Engagement at PRHE. She has a wealth of knowledge and understanding of how toxic chemicals impact susceptible populations and communities and is skilled in addressing these issues with decision-makers in Washington, DC. Rashmi completed her doctorate in the Integrated Toxicology and Environmental Health Program at Duke University, specializing in neurodevelopmental toxicology.
Thank you to Swati Rayasam and Dan Axelrad for help with fact checking and editing this blog.