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

Readers of this blog will recall the major concerns EDF, EPA’s science advisors, and many others have raised about the Trump EPA’s systematic exclusion from its risk evaluations of all human exposures to chemicals released to air, water and land.  EPA has taken this illegal, unscientific and un-health protective approach across the board in the risk evaluations it has issued to date in draft or final form under the Toxic Substances Control Act (TSCA).

EDF first flagged the emergence of this fatally flawed approach over two years ago, and again when it was applied to the likely human carcinogen 1,4-dioxane, one of the first 10 chemicals undergoing TSCA risk evaluations.  Since then the Trump EPA has doubled down, repeatedly defying its own science advisors who have called out this deficiency in virtually all of their peer reviews of EPA’s draft risk evaluations.  EPA is clearly refusing to budge, issuing two final risk evaluations for methylene chloride and 1-bromopropane that seek to codify the approach.[pullquote]EPA’s Office of Water is deferring any decision on whether to regulate 1,4-dioxane in drinking water, pending completion of a risk evaluation that expressly excludes that exposure.  That exclusion is in turn based on the TSCA office’s claim that the Office of Water already has it covered.[/pullquote]

The asserted basis for ignoring tens of millions of pounds of these chemicals released annually is EPA’s claim that the releases are adequately managed under other laws the agency administers.  To bolster that claim, EPA also asserts that it has closely consulted with the EPA offices that administer those other laws to ensure this is the case.  Let’s take a closer look at the nature – and apparent effects – of that consultation in one setting:  1,4-dioxane in drinking water, which falls under the authority of the Safe Drinking Water Act (SDWA) administered by EPA’s Office of Water.  Read More »