Center for Progressive Reform

New CPR White Paper Proposes 47 Priority Chemicals for EPA's IRIS Toxic Chemical Database

by Lena Pons

In October, EPA requested nominations for substances that it should evaluate under the Integrated Risk Information System (IRIS). Today CPR releases Setting Priorities for IRIS: 47 Chemicals that Should Move to the Head of the Risk-Assessment Line -- a paper that we've submitted to EPA as our nominations for priority chemicals.

Following up on our recent IRIS reform white paper, which made recommendations for how to improve the IRIS process and complete more reviews of basic toxicology information, CPR has completed additional research into how EPA sets priorities for IRIS assessments. The paper was written by CPR President Rena Steinzor, Policy Analyst Matt Shudtz, and myself.

We found 253 chemicals that have been identified by EPA regulatory program offices that are missing key IRIS information. From this list, we named 47 that we believe need to be the highest-priority, based on the air toxics, drinking water, and Superfund program offices’ most pressing needs. EPA is currently working on assessments for 17 of these substances.

Regulatory decisions under the Clean Air Act, Superfund, and Safe Drinking Water Act are all dependent on risk assessments which rely on the numerical toxicology data contained in the IRIS database. Delaying these assessments requires EPA program offices to rely on less rigorous estimates of the risks associated with toxic substances. This can negatively impact regulatory decisions -- how can you properly protect the public from exposure to chemicals if you haven't first adequately assessed the health effects of those chemicals?

This is no abstract problem; we're allowing the release of these chemicals -- sometimes a lot of them -- into the air near where real people live. Our paper shows that in some cases, individual communities are near facilities releasing a number of un-assessed chemicals. Residents of Geismer, Louisiana, for example, are exposed to 14 air toxics that do not have IRIS assessments, according to EPA data.

Our paper recommends a two-step process for improving the IRIS agenda setting process. First, EPA should consult with regulatory program offices and take regulatory priorities into consideration. Second, EPA should take environmental justice into consideration, and identify whether there are communities with exposures to a large number of chemicals missing from the IRIS database.