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EPA Requests Public Comment on the Latest Systematic Review Protocol Under the IRIS Program

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EPA Press Office (

WASHINGTON (March 20, 2019) — The U.S. Environmental Protection Agency (EPA) recently announced a 45-day public comment period associated with the release of the Systematic Review Protocol for the Hexavalent Chromium [Cr(VI)] IRIS Assessment. The 45-day public comment period began March 15, 2019 and ends April 29, 2019. EPA also announced a public science meeting (by webinar) scheduled for April 24, 2019 to provide an opportunity for the public to offer comments on the systematic review protocol.

The systematic review protocol is a methods document that describes how the IRIS human health assessment of hexavalent chromium will be conducted and builds on the preliminary materials released for public comment in 2014. When final, the assessment will update the 1998 IRIS assessment of hexavalent chromium. As described in the systematic review protocol, the updated assessment will include evaluations for cancer, as well as noncancer effects of the respiratory, gastrointestinal, hepatic, hematological, immunological, reproductive, and developmental systems associated with both inhalation and ingestion of hexavalent chromium.

EPA's IRIS Program develops assessments that provide toxicity values for health effects resulting from exposure to chemicals found in the environment. Hexavalent chromium has been identified as a priority by EPA’s Office of Water (OW) and the Office of Land and Emergency Management (OLEM). Through the IRIS Program, EPA provides high quality science-based human health assessments to support the Agency's regulatory activities and decisions to protect human health.

Hexavalent chromium occurs naturally in the environment and can also be released into the environment as a result of human (industrial) activities. It is found in soil, air, groundwater, and drinking water. Uses include chrome plating, pigment manufacturing (textile dyes, printing inks, and glass production), stainless steel production, leather manufacturing, drilling muds, and chemical synthesis. Hexavalent chromium is also widely used as a corrosion inhibitor, including within water-cooled systems.

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To register for the public science meeting (webinar), please visit: