Toxic Substances Control Act (TSCA) Implementation: How the amended law has failed to protect vulnerable populations from toxic chemicals in the U.S.

Exposures to industrial chemicals are widespread in the population and can increase the risk of adverse health effects such as cancer, developmental disorders, respiratory effects, diabetes, and reproductive problems. The amended Toxic Substances Control Act (amended TSCA) requires the U.S. Environmental Protection Agency (EPA) to evaluate risks of chemicals in commerce, accounting for risk to potentially exposed and susceptible populations, and to mitigate risks for chemicals determined to pose an unreasonable risk to human health and the environment. This analysis compares EPA’s first 10 chemical risk evaluations completed under amended TSCA between June 2020 and January 2021 to best scientific practices for conducting risk assessments based on recommendations from authoritative scientific bodies. We find that EPA’s risk evaluations underestimated human health risks of chemical exposures by excluding conditions of use and exposure pathways; not considering aggregate exposure and cumulative risk; not identifying all potentially exposed or susceptible subpopulations, and not quantifying differences in risk for susceptible groups; not addressing data gaps; and using flawed systematic review approaches to identify and evaluate the relevant evidence.  We present specific recommendations for improving the implementation of amended TSCA to use the best available science to ensure equitable, socially just safeguards to public health. Failing to remedy these shortcomings found in the first 10 chemical risk evaluations will result in continued systematic underestimation of risk for these chemicals and the chemicals still to be evaluated under amended TSCA. The stakes are high for public health because generations of children have been born pre-polluted due to the widespread use of industrial chemicals.Exposures to industrial chemicals are widespread in the population and can increase the risk of adverse health effects such as cancer, developmental disorders, respiratory effects, diabetes, and reproductive problems. The amended Toxic Substances Control Act (amended TSCA) requires the U.S. Environmental Protection Agency (EPA) to evaluate risks of chemicals in commerce, accounting for risk to potentially exposed and susceptible populations, and to mitigate risks for chemicals determined to pose an unreasonable risk to human health and the environment. This analysis compares EPA’s first 10 chemical risk evaluations completed under amended TSCA between June 2020 and January 2021 to best scientific practices for conducting risk assessments based on recommendations from authoritative scientific bodies. We find that EPA’s risk evaluations underestimated human health risks of chemical exposures by excluding conditions of use and exposure pathways; not considering aggregate exposure and cumulative risk; not identifying all potentially exposed or susceptible subpopulations, and not quantifying differences in risk for susceptible groups; not addressing data gaps; and using flawed systematic review approaches to identify and evaluate the relevant evidence.  We present specific recommendations for improving the implementation of amended TSCA to use the best available science to ensure equitable, socially just safeguards to public health. Failing to remedy these shortcomings found in the first 10 chemical risk evaluations will result in continued systematic underestimation of risk for these chemicals and the chemicals still to be evaluated under amended TSCA. The stakes are high for public health because generations of children have been born pre-polluted due to the widespread use of industrial chemicals.