Winter 2023

What’s New at Gradient

Awards and Announcements


Ifeoluwa A. Bamgbose and Rachel Y. Chang are now Diplomates of the American Board of Toxicology (DABT).

Barbara D. Beck has been recertified as a Fellow in the Academy of Toxicological Sciences (ATS).

Steven R. Boomhower was named to the Editorial Board of the scientific journal Frontiers in Environmental Health.

Steven R. Boomhower was invited to be an Adjunct Lecturer at Georgetown University for the Spring 2023 semester.

Kurt Herman was appointed to serve on the Board of Health of the Town of Concord, MA.

Tim Verslycke has been elected to serve as President of the International Board of Environmental Risk Assessors (IBERA), a program of the Society of Environmental Toxicology and Chemistry (SETAC), for 2023-2024.



The following Gradient employees have been promoted to Principal or Principal Scientist:



Afshar-Mohajer, N; Wu, CY. 2022. “Use of a drone-based sensor as a field-ready technique for short-term concentration mapping of air pollutants: A modeling study.” Atmos. Environ.

Upcoming Presentations


Society of Toxicology (SOT) 62nd Annual Meeting. March 19-23, 2023. Nashville, TN.

  • “Challenges in Evaluating Risks from Lead Exposure.” B. Beck, J. Cohen, S. Boomhower, C. Marsh.
  • “Updates to ISO 10993-17 for Medical Device Toxicological Risk Assessments: What You Need to Know.” Exhibitor-hosted session. L. Borton.
  • “Ranking Surrogate Suitability for Read-Across of Medical Device Extractables: A Case Study of Irganox-Related Compounds.” R. Chang.
  • “New Approach Methods for Toxicological Risk Assessment of Extractable Compounds from Biodegradable/Bioresorbable Medical Devices.” Workshop. J. Cohen.
  • “Comparison of Contrast Media Components with International Organization for Standardization (ISO) Standard Solvents to Determine Representative Patient Risk.” C. Meakin, I. Hadley, L. Borton.
  • “Framework for In Silico Toxicity Screening of Novel Odorants.” I. Mohar.
  • “Considerations in Evaluating Dermal Absorption of Per- and Polyfluoroalkyl Substances (PFAS).” A. Yeh, L. Kerper, R. Prueitt, B. Beck.

ACS Spring 2023 – Crossroads of Chemistry. March 26-30, 2023. Indianapolis, IN.

  • “The Effects of Atmospheric Oxidation on Benzo[a]pyrene Aerosol Particles: Mutagenicity and Potential Health Effects.” A. Hrdina, S. Kaushal, N. Drury, J. Cohen, B. Engelward, J. Kroll.

Previously Presented


Battelle 2023 Sediments Conference. January 9-12, 2023. Austin, TX.

  • “Identifying and Managing Uncertainty in Environmental Response Costs at Sediment Sites.” K. Herman, M. Pollock, N. Slagowski, S. Zhao, J. Rice.
  • “Calculation of Contaminant Mass in Sediments for Use in Cost Allocation.” J. Kneeland, E. Butler, R. Mozumder.
  • “Where Science and Cost Apportionment Collide: Contaminant Loading from Upland Soils to Sediments.” M. Mayo, J. Rominger, N. Grasso.
  • “Digitizing the Haystack: Streamlined Techniques to Pinpoint Potentially Responsible Parties.” M. Mayo, J. Rice, S. Zhao. (Presented as both a talk and a poster.)
  • “Identifying Byproduct (Also Known As “Inadvertently Generated”) Polychlorinated Biphenyls in Water Bodies.” J. Rominger, K. Herman, A.P. Tcaciuc.

By The Way… 


Conservation efforts have made it possible for previously endangered species – including the humpback whale and jaguar – to recover from the threat of extinction.