Richard Denison, Ph.D., is a Lead Senior Scientist.

The 2016 Lautenberg Act amendments to the Toxic Substances Control Act (TSCA) expanded and enhanced Congress’ vision for how the Environmental Protection Agency (EPA) should evaluate and mitigate the potential risks of chemicals.  [pullquote]The industry’s interest is simple:  The fewer exposures to a chemical EPA looks at, the more likely it is to find those it does look at safe.[/pullquote]

The original TSCA was intended to encompass the full lifecycles of chemicals, from manufacturing to use to disposal, authorizing EPA to regulate any of those activities.  It gave EPA co-authority with the Occupational Safety and Health Administration (OSHA) over chemical exposures in workplaces and with the Consumer Product Safety Commission (CPSC) over chemical exposures from consumer products.  And it provided a wide array of means by which EPA could regulate chemicals to address unreasonable risks it identified, ranging from requiring warnings to limiting the amount of a chemical that could be used in a certain way to an outright ban on all uses of a chemical.  Unfortunately, the original law also contained fatal flaws that rendered this vision unachievable in practice.

Congress finally stepped in to address those flaws through the 2016 amendments.  But the amendments also did something else:  they added several elements that further expanded what EPA was to include in addressing chemical risks.  Congress explicitly required that EPA identify and protect against risks not only to the general population, but to vulnerable subpopulations at potentially greater risk due to heightened exposure or greater susceptibility to a given exposure.  It mandated that EPA prioritize chemicals, and evaluate and regulate their risks, under the chemicals’ “conditions of use,” a term Congress defined broadly to encompass not only the full chemical lifecycle, but also all of the “intended, known, or reasonably foreseen” activities that occur at each lifecycle stage.

And Congress directed EPA to determine whether a chemical’s risks were unreasonable and warranted regulation based solely on its effects on human health or the environment, without regard to costs or other non-risk factors.  Only after EPA completed its science-based evaluation of risks and determined regulation was warranted, was EPA to consider costs and other non-risk factors, and then only in deciding how best to eliminate the unreasonable risk.  Congress also retained the provision of TSCA that relegates to the very last step any consideration of whether other authorities – be they EPA’s or other agencies’ – could be used instead of TSCA.

Each of the new elements has a strong basis in the large body of science that has emerged over the decades since TSCA first passed in 1976 that elucidates how we are exposed to chemicals, how they can affect our basic biology, and how variability in the human population mediates the potential impacts.

Any objective reading of the new law would lead one to expect, therefore, that the breadth and depth of EPA’s chemical risk evaluations would grow considerably.  And for most of the first year after passage of the new law, that was where things appeared to be heading.

Enter the Pruitt EPA.   Read More »