The United States Environmental Protection Agency (EPA) has published its proposed rule for the prioritization of existing chemicals for the risk evaluation mandated under the Frank R. Lautenberg Chemical Safety for the 21st Century Act (LCSA). The LCSA granted EPA new authority to assess and manage the risk of existing chemicals, and it gave EPA one year to create regulations to fulfill this new authority, including a rule defining a risk-based screening process to designate existing chemicals as either high or low priority. In the proposed rule, EPA outlines four phases it intends to use to accomplish its prioritization task:

(1) Pre-Prioritization – The LCSA directs EPA to consider hazard, exposure, proximity to drinking water sources, potentially exposed or susceptible subpopulations, production volume, and conditions of use when it makes its designation. In order to ensure that EPA makes an appropriate designation, the proposed rule uses these factors in the pre-prioritization phase to narrow the pool of candidate chemicals. EPA will also consider whether the chemical...