Evaluating risk, exposure, and detection capabilities for chemical threats in water

ABSTRACT

The unexpected release of chemicals into the environment requires estimation of human health risks, followed by risk management decisions. When environmental concentrations of toxicants are associated with adverse health risks, the limit for analytical measurement needs to be at or below the risk threshold. The aim of this study was to assess chemical contaminants that have the potential to produce acute adverse human health impacts following oral consumption of contaminated drinking water. The U.S. Environmental Protection Agency’s (EPA) Candidate Contaminant List, version 4 (CCL4) and EPA’s Selected Analytical Methods (SAM) document were screened to identify 24 chemicals that exist as a solid or liquid at room temperature, with acute oral LD₅₀ (lethal dose in 50% of the test population) values < 500 mg/kg-d and water solubility > 500 mg/L at ambient temperature. While these screening criteria were used to identify prioritized needs for targeted research, it does not imply that other chemicals on the CCL4 and SAM lists are not issues in acute and chronic exposures. Of these 24 most toxic and most soluble chemicals, this evaluation identified 6 chemicals (2-chlorovinylarsonous acid, lewisite, N-nitrosopyrrolidine, N-nitrosodiethylamine, 3-hydroxycarbofuran, and triethylamine) lacking either sufficient toxicity value information or analytical sensitivity required to detect at levels protective against adverse effects in adults for acute exposures. This assessment provides an approach for gap identification and highlights research needs related to water contamination incident involving these six priority chemicals.

KEYWORDS:

• Risk
• exposure
• detection
• drinking water
• chemical threat

Acknowledgments

The authors would like to thank Steve Allgeier for consulting with the authors on the development of this manuscript. The authors would also like to thank Latisha Mapp, Adrienne Keel, and Joyce Donohue for their assistance in reviewing and improving the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability Statement

The data that support the findings of this study are openly available in EPA’s Science Inventory at http://doi.org/10.23719/1521126 reference number [to be assigned after acceptance].

Disclaimer

The U.S. Environmental Protection Agency (EPA) through its Office of Research and Development managed the research effort described herein. It has been reviewed by the Agency but does not necessarily reflect the Agency’s views or policies. No official endorsement should be inferred. EPA does not endorse the purchase or sale of any commercial products or services.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.