Contaminants of emerging concern (CECs), including pharmaceuticals and personal care products (PPCPs), are increasingly being detected at low levels in surface water, and there is concern that these compounds may have an impact on aquatic life. It is important for EPA to be able to evaluate the potential impact of CECs and PPCPs on aquatic life and have an approach for determining protective levels for aquatic organisms.
These chemicals have features that require additional consideration when applying existing ambient water quality criteria for the protection of aquatic life, using EPA’s 1985 Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Life and Their Uses.
There are many CECs and PPCPs that act as so-called endocrine disruptors (EDCs). EDCs are compounds that alter the normal functions of hormones resulting in a variety of health effects. EDCs can alter hormone levels leading to reproductive effects in aquatic organisms, and evaluating these effects may require testing methodologies not typically available along with endpoints not previously evaluated using current guidelines.
The emerging contaminants may also demonstrate low acute toxicity but cause significant reproductive effects at very low levels of exposure. In addition, the effects of exposure to aquatic organisms during the early stages of life may not be observed until adulthood. Therefore, traditional toxicity test endpoints may not be sufficiently comprehensive for criteria derivation for these chemicals and the chemicals may also have specific modes of action that may affect only certain types of aquatic animals (e.g., vertebrates such as fish).
Therefore, EPA developed a White Paper Aquatic Life Criteria for Contaminants of Emerging Concern: Part I Challenges and Recommendations detailing the technical issues and recommendations to serve as a basis for modifying the 1985 guidelines. These modifications should enable the Agency to better address CECs and develop ambient water quality criteria when appropriate for protection of aquatic life that makes the best use of available science.
EPA’s Office of Water asked the Science Advisory Board (SAB) for advice on the scientific merit of a white paper that identifies and addresses technical issues in deriving aquatic life criteria for emerging contaminants such as pharmaceuticals and personal care products exhibiting endocrine disrupting activity or other toxic mechanisms.
