EPA Starts the IRIS Review Process for Three Chemicals

On September 18th, the Environmental Protection Agency (EPA) announced the start of the review process under Integrated Risk Information System (IRIS) for three chemicals – ethylbenzene, nitrate and nitrite, and chloroform. This is the first step in a 14-step process for an IRIS review, and this review process will likely take several years.
The likelihood, as well as the timing, for any potential revisions to any drinking water regulations is not clear at this time. After these reviews, the Office of Groundwater and Drinking Water (OGWDW) would have to assess the revised risk numbers and make the decision on whether a revision to a regulated is warranted (or not warranted) as part of the Agency’s Six-Year Review process.  EPA’s Third Six-Review of Existing Drinking Water Regulations was published on January 11, 2017, so at this point, the Fourth Six-Year Review is scheduled to be published sometime in early 2023. If a decision is made at that time to move forward with a revision of a regulation, any regulatory revision is also a multi-year process.