Vulnerable populations bear the burden of EPA’s inadequate policy on industrial chemicals

In 2016 with bipartisan support, the Frank R. Lautenberg Chemical Safety for the 21st Century Act became law, updating the Toxic Substances Control Act (TSCA). Before the update, TSCA was widely seen as ineffective at protecting public health, especially for susceptible groups like pregnant women, infants, children, the elderly, and workers. Under the new Lautenberg amendments to TSCA, EPA has begun to assess health risks of the first 10 chemicals, but is EPA applying the best available science on susceptibility to safeguard the health of at-risk groups?

In a peer-reviewed commentary recently published in PLOS Biology, my co-authors and I highlight that that EPA’s plans for risk evaluation of the first ten chemicals do not  incorporate established science on factors contributing to increased susceptibility or exposure and will underestimate risk.

It has been well established that susceptible groups can be especially harmed by exposure to industrial chemicals. To understand susceptibility related to an environmental pollutant, think about how a chemical like lead can hurt children in a more pronounced way than adults. Children’s bodies are still developing;  placing their health at higher risk, and children’s behaviors (e.g., putting things in their mouth, crawling on the floor) can increase exposures. As shown in the Figure below, age, life stage, pre-existing disease, pregnancy status, genetic variation, and many other factors can contribute to increased susceptibility. Social vulnerabilities like poverty can prevent people from being able to reduce harms due to lack of access to nutrition or medical care.

fig 1
Exposure disparities (such as from proximity to polluting industries or use of consumer products), social vulnerabilities (such as lack of access to health care) and biological susceptibilities (such as age or pre-existing disease) create differences in how chemicals affect a person’s health, contributing to adverse health outcomes and disparities for vulnerable populations throughout the lifespan. Image created by Swati Rayasam.

To protect susceptible groups as required by law, we make specific recommendations to improve the scientific basis of EPA’s risk evaluations and align them with evidence-based principles to protect public health. These principles are articulated in the National Research Council’s 2009 report, Science and Decisions: Advancing Risk Assessment, including:

  • Incorporate biological and sociodemographic factors that affect susceptibility (e.g., age, life stage, underlying disease),
  • Add up chemical exposures to susceptible groups from all pathways such as air, water, food, skin contact (a.k.a., aggregate exposure), and
  • Accurately detect highly exposed groups, including those with occupational exposures.

These common-sense, science-based guidelines are not new; what is new is EPA’s complete departure from this science despite the law mandating EPA to protect the health of susceptible and highly exposed groups.

Today approximately 9.5 trillion pounds of about 40,000 industrial chemicals are currently in production based on EPA estimates. Under the new legal framework in the Lautenberg amendments, EPA has started to evaluate risk for an important set of 10 chemicals. How EPA assesses susceptible and highly exposed populations is critically important to public health. The first 10 chemicals under evaluation account for a combined production volume of over 1 billion pounds per year. In addition, EPA’s decisions on key details in the risk evaluations will influence its future evaluations and the level of toxic chemicals in our homes, communities and bodies for generations—with our most vulnerable populations disproportionately bearing the burden of health consequences.

This has been the case for decades, which is why Professor Carl Cranor concluded the public was being “legally poisoned” under the old TSCA. Without correctly identifying and taking into account risks to susceptible groups, it’s unlikely that EPA’s actions under new Lautenberg TSCA will change this situation. However, with strong, timely, and evidence-based public health action, EPA has the opportunity – and we argue legal duty — to reverse this legacy, limit dangerous chemicals, and improve the health of our families and communities.