Protecting Human Health: That Explains It!

By Elizabeth Erwin

Child plays with water.

EPA's IRIS Program provides health effects information to help protect public health and the environment.

This past December, I had the opportunity to attend the annual Society for Risk Analysis (SRA) meeting in Charleston, SC. One of my responsibilities was to cover a symposium on EPA’s Integrated Risk Information System (IRIS) chaired by Becki Clark, Acting Director of my EPA office, the National Center for Environmental Assessment (NCEA).

Over the past year, I have become very familiar with IRIS, as a large part of my job is to communicate to the public, other federal agencies, and stakeholders what IRIS is, what it isn’t, and what it does to protect human health and the environment.

When I mention IRIS to friends and family, I’m often met with quizzical expressions. After several failed attempts at an explanation that included chemical names like “hexabromocyclododecane” and other scientific mouthfuls, I began giving them the bottom line: while IRIS assessments are not regulations or by themselves full risk assessments, the information they contain is an important basis for decisions that protect the health of all Americans.

Obviously, each of us has at some point taken a drink of tap water, inhaled deeply while enjoying an afternoon outside, or tracked soil into our homes. We perform these and dozens of other mundane daily activities without giving a second thought to potential harmful consequences, thanks in large part to EPA’s actions, many of which are based on IRIS human health assessments of more than 550 chemical substances.

Earlier this year, EPA finalized the long-awaited non-cancer assessment for dioxin, a major milestone for the Agency. Dioxins are toxic chemicals that exist in the environment naturally and can be released in greater quantities through forest fires, backyard burning of trash, certain industrial activities, and residue from past commercial burning of waste.

This final IRIS assessment is the latest effort in a successful, coordinated strategy by the Federal government that has reduced known and measurable air emissions of dioxins in the United States by about 90 percent since 1987.

Risk assessors, health professionals, and state, local, and international governments can now use these latest findings to guide future efforts to identify any residual sources of dioxin and protect public health.

Achievements such as this are what make me proud to be associated with EPA’s IRIS Program, especially when I get that oh-so-common question, “So, what do you do?” Attending the IRIS presentation reminded me that to answer that question, all I have to say is simply, “I help support the science that protects human health” – because that’s exactly what the IRIS Program does.

About the Author:  Elizabeth Erwin is a member of EPA’s science communication team where she helps make IRIS and other EPA science programs and assessments available and accessible.

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