Gradient scientists are at the forefront of scientific developments in the PIE field. We have developed effective strategies to address a variety of PIE projects, including a tiered fate and effects data collection and assessment framework for potential environmental risks of existing and new APIs. We have provided comments on proposed regulations, developed best practices for wastewater and biosolids management, prepared environmental assessments to support regulatory filings in the US and Europe (including for antibiotics and endocrine-active APIs), published impactful reports in the scientific literature, and communicated PIE risks to the public and other stakeholders.
Project Examples:
Risk-Based Remedial Strategy for a Pharmaceutical Manufacturing Plant. Gradient developed a risk-based closure strategy for a former pharmaceutical synthesis facility. Our strategy included identifying a subset of potentially risk-driving compounds and threshold concentrations protective of human and ecological receptors to form the basis of site cleanup.
Environmental Fate and Effects Database. Gradient reviewed pharmaceutical environmental fate and ecological effects data from proprietary, published, and governmental sources. We synthesized this data into a database for preparing ecological assessments and establishing risk-based wastewater discharge limits.
Ecological Benchmarks for Pharmaceutical Wastewater Treatment. Gradient calculated predicted aquatic no adverse effect concentrations (PNECs) for three endocrine-active pharmaceutical ingredients. The PNECs were used to establish effluent limits at a manufacturing plant.
Publications:
Bamgbose, IA; Vo, J; Verslycke, T. 2025. “A read-across approach to support environmental assessment of data-poor pharmaceuticals” (submitted).
Bamgbose, IA; Mohar, I; Verslycke, T. 2020. “Are Existing Environmental Assessment Approaches Appropriate for Novel Drug Products?” Presented at the American College of Toxicology (ACT) 41st Annual Meeting, Austin, TX, November 12-19.
Marty, MS; Blankinship, A; Chambers, J; Constantine, L; Kloas, W; Kumar, A; Lagadic, L; Meador, J; Pickford, D; Schwarz, T; Verslycke, T. 2017. “Population-relevant endpoints in the evaluation of endocrine-active substances (EAS) for ecotoxicological hazard and risk assessment.” Integr. Environ. Assess. Manag. 13(2):317-330.
Williams, M; Backhaus, T; Bowe, C; Choi, K; Connors, K; Hickmann, S; Hunter, W; Kookana, R; Marfil-Vega, R; Verslycke, T. 2016. “Pharmaceuticals in the environment: An introduction to the ET&C special issue.” Environ. Toxicol. Chem. 35(4):763-766.
Verslycke, T; Mayfield, DB; Tabony, JA; Capdevielle, M; Slezak, B. 2016. “Human health risks of triclosan in land-applied biosolids.” Environ. Toxicol. Chem. 35(9):2358-2367.
Boxall, ABA; Rudd, MA; Brooks, BW; Caldwell, DJ; Choi, K; Hickmann, S; Innes E; Ostapyk, K; Staveley, JP; Verslycke, T et al. 2012. “Pharmaceuticals and personal care products in the environment: What are the big questions?” Environ. Health Perspect. 120(9):1221-1229.
Verslycke, T; Mastrocco, F; Lemay, JC. 2012. “A Concordance Assessment of Predicted-no-effect-concentration (PNEC) Aquatic Toxicity Data for Pharmaceuticals.” Presented at SETAC 6th World Congress, Berlin, Germany, May 20-24.
