Identifying Hormonally Active Compounds, Pharmaceuticals and Personal Care Product Ingredients of Health Concern from Potential Presence in Water Intended for Indirect Potable Reuse
Year Released: 2010
Funding Partners: Bureau of Reclamation, California State Water Resources Control Board, Clark County Water Reclamation District
Total Investment: $107,673.17 (Cash: $104,631.88, In-Kind: $3,041.29)
Principal Investigator: Shane A. Snyder, Ph.D., Southern Nevada Water Authority
Over the past decade, a diversity of emerging contaminants has been identified in waters around the globe. Of particular interest are pharmaceuticals and personal care products (PPCPs) and potential endocrine disrupting compounds (EDCs), both of which are generally detected in extremely low (sub-µg/L) concentrations in water. Despite these low levels, public, scientific, and regulatory communities have shown increasing interest and concern about the potential occurrence of these compounds in drinking water and their potential health effects. The vast majority of these compounds are not regulated, and developing toxicity criteria can be time consuming and resource intensive.
Goals and Objectives
The project reviews methodologies for developing screening level human health risk-based criteria for PPCPs and EDCs potentially present in water intended for indirect potable reuse and develop decision criteria.
The research approach is to:
- Develop scientifically based decision criteria to support selection of an appropriate methodology for identifying human health risk-based screening levels for emerging compounds (specifically PPCPs and EDCs), if a “new” chemical (i.i, one without an existing human health risk-based toxicity criterion) is found in source or drinking water.
- Review and establish the advantages/disadvantages and resource requirements of several possible moethods for rapidly developing health risk-based screening levels relative to accepted methodologies (e.g., the U.S. EPA “reference dose” approach), for a representative set of case study compounds.
- Present the case studies and finding sat a meeting of experts, regulators, and stakeholders to support discussion and derive consensus on a recommended approach.
- Develop a report summarizing the evaluations and workshop conclusions
Findings and Conclusions
This approach will help in the selection of an appropriate screening methodology to rapidly develop a screening level if a “new” chemical is detected in water. If the concentration of the contaminant is at or above this screening level, then more detailed evaluation of the toxicity and occurrence of the compound is recommended; if the concentration is below the screening level, then the risk to public health is predicted to be well below levels of concern and the presence of the compound does not alone warrant further toxicological studies. Screening values could also be used to develop method reporting limits based on human health endpoints.
Using the approach developed in this report, it is possible to rapidly establish conservative health risk-based screening level values.