The SOT Weekly Update published an essay written by Barbara Beck titled, “My Circuitous Scientific Path through Academic, Industry, and Consulting” as part of a “series designed to celebrate SOT member diversity and showcase the diverse pathways and experiences of its members.”

The essay starts with, “I have a confession regarding my scientific and career journey to toxicology.”  Read the essay.




Gradient has joined the Geosyntec family of companies. This partnership will advance the shared vision of Geosyntec and Gradient to bring robust and trusted scientific analyses to bear on diverse and challenging environmental, health, and safety issues.

Geosyntec is a consulting and engineering firm specializing in collaborating with both private and public sector clients to tackle new ventures and complex challenges related to our environment, natural resources, products, and civil infrastructure. With a collective staff exceeding 2,200 professionals, including engineers, scientists, and various technical and project support personnel, Geosyntec operates from over 100 offices across the United States, Australia, Canada, Finland, Ireland, Spain, Sweden, the United Arab Emirates, and the United Kingdom.

Manu Sharma, MS, PE, President of Gradient, said, “Since our inception, Gradient has held steadfast focus on our dual mission of providing trusted scientific analysis on complex environmental and health issues while supporting a collaborative, collegial, and multidisciplinary team. Geosyntec was built on similar values and has also grown and flourished by supporting its people and maintaining a commitment to the highest professional standards. Together, Gradient and Geosyntec will harmonize our strengths to address the most consequential environmental, health, and safety challenges facing our clients around the world.”

Peter Zeeb, PhD, PG, President, and CEO of Geosyntec, said, “Geosyntec and Gradient are both unwavering in our commitment to rigorous science and engineering delivered with exceptional client service. Gradient tackles complex environmental, health, and safety issues for their clients and brings a complementary, deep subject matter expertise and several new service offerings to our family of companies. This partnership enables us to provide a broader scope of services to our combined clients and accelerates our ability to service target markets focused on emerging and current societal-scale challenges.”

Learn more about Geosyntec at

Morrissey Goodale (Morrissey Goodale | Advisory Services for the AEC Industry)  served Gradient as an advisor on the transaction.

Gradient announces five employees promoted to Principal and Principal Scientist in 2024.

John Kondziolka, M.S. is promoted to Principal Scientist: Mr. Kondziolka’s practice focuses on competition for water resources, contaminant fate and transport, and assessing risk for sustainable chemical transitions.

Lindsey K. Borton, M.P.H. is promoted to Principal:  Ms. Borton has a practice in biological evaluation and toxicological risk assessment of medical devices.

Robyn L. Prueitt, Ph.D., DABT is promoted to Principal: Dr. Prueitt has developed a practice in toxicology, carcinogenesis, and human health risk assessment.

Jeffrey T. Rominger, Ph.D. is promoted to Principal: Dr. Rominger is an environmental engineer and scientist at Gradient whose practice focuses on chemical fate and transport, environmental forensics, and environmental fluid mechanics.

Caroline B. Tuit, Ph.D. is promoted to Principal: Dr. Tuit is an environmental chemist with expertise in data quality and environmental forensics for evaluating the sources, fate, and transport of chemicals.

Here is wishing them the best in their new leadership roles.

Gradient is presenting at the 2024 Annual Meeting of the Society of Toxicology, taking place March 10-14, 2024, in Salt Lake City, Utah. See presentation details below, and click the links to view poster abstracts.

Gradient’s 2024 SOT Meeting Presentations:

“Considerations for Identification Confidence in Chemical Characterization and Risk Assessments”
Isaac Mohar, Joshua Young (US FDA), Eric Sussman (MCRA)
Exhibitor-Hosted Session
Room 155 C
3/13/24 @ 3:00 pm-4:00 pm

P484: Application of a 3D QSAR Approach for the Re-evaluation of Organophosphorus Compounds for Cohort of Concern Identification
Alex Gauthier, Thomas Dugan, Hayley Gadol
Session: Medical Devices
3/11/24 @ 9:15 am-11:15 am

P324: Deriving an Allowable Exposure Limit for Isobornyl Acrylate for Skin Sensitization in Skin-Contacting Consumer Products
Seth Larch, Rebecca Ticknor, Isaac Mohar, Tom Lewandowski
Session: Skin Sensitization
3/11/24 @ 9:15 am-11:15 am

P489: Modifications to Toxtree’s Revised Cramer Module in the Context of Cramer Classification Predictions for Medical Device Extractables
Pranav Mashankar, Brigitte Cronin, Rachel Chang, Joel Cohen
Session: Medical Devices
3/11/24 @ 9:15 am-11:15 am

P482: What Is a More Conservative Approach for Risk Assessment? Comparing Materials Characterization Data with an Extractables Profile for a Permanent Orthopedic Implant
Cassandra Meakin, Catalina Restrepo, Stephanie Kearing, Lindsey Borton
Session: Medical Devices
3/11/24 @ 9:15 am-11:15 am

P483: Derivation of Fit-for-Purpose Non-Cancer Duration-Based TTC Values for Medical Device Constituents
Taylor Builee (Taylor Builee LLC), Sherry Parker (SParker Toxicology and Consulting), Bindu Prabhakar (WuXi AppTec), Frances Hsia (Boston Scientific), Alessia Stornetta (Boston Scientific), Stephen Bond, Michael Peterson, Valériane Levelut (NAMSA)
Session: Medical Devices
3/11/24 @ 9:15 am-11:15 am

P172: Considerations for Deriving a Safe Intake of Propylene Glycol
Charlotte Marsh, Steven Boomhower, Ari Lewis
Session: Safety Assessment: Non-pharmaceutical
3/11/24 @ 11:45 am-1:45 pm

P156: Evaluating the Potential for Reproductive Effects from Intermittent Lead Exposures Using Blood Lead Modeling Under Proposition 65
Steven Boomhower, Jiayang Chien, Rosemary Mattuck, Barbara Beck
Session: Risk Assessment I
3/11/24 @ 2:15 pm-4:15 pm

P375: Critical Analysis of Sperm Parameter Data Used as the Basis for a Tolerable Daily Intake for Bisphenol A
Mary Hixon, Robyn Prueitt, Julie Goodman
Session: Reproductive Toxicology I
3/12/24 @ 11:45 am-1:45 pm

P117: Protecting Against Adverse Reproductive and Gestational Outcomes from Workplace Exposures: Screening Assessments for Developmental and Reproductive Toxicity
Nicole Olgun, Mary Hixon, David Dodge, Tom Lewandowski
Session: Risk Assessment II
3/12/24 @ 11:45 am-1:45 pm

P156: Critical Evaluation of Immunotoxicity Data Used as the Basis for a Tolerable Daily Intake for Bisphenol A
Robyn Prueitt, Mary Hixon, Julie Goodman
Session: Risk Assessment III
3/12/24 @ 2:15 pm-4:15 pm

“#1212: Looking into the Future: How to Evaluate Safety of New and Unique Consumer Electronics”
Tom Lewandowski
Informational Session: From My Cosmetics to Smart Watch, Toxicology Touches It All!
3/12/24 @ 4:45 pm – 6:05 pm, Grand Ballroom J

P414: Applying EEDmax Approach from ISO 10993-17:2023 to Risk Assessment of DEHP
Colleen Clarke, Perry Piatos, Seth Larch, Rachel Chang
Session: Regulation/Policy
3/13/24 @ 2:15 pm-4:15 pm

Gradient will present at Energy, Utility & Environment Conference (EUEC) 2024. February 13-15, 2024. Dallas, TX.

Gradient Presenting at EBC 5th Annual PFAS Seminar. February 6, 2024. Framingham, MA.

Ifeoluwa A. Bamgbose was awarded a Certificate in Regulatory Sciences from the University of Arkansas for Medical Sciences (UAMS) in August 2023.

Gradient Principal Scientist Dr. Isaac Mohar will be presenting at the Pharm Ed Resources, Inc. Extractables & Leachables West 2023 conference, November 2-3, 2023 in La Jolla, CA.

The Environmental Business Council (EBC) of New England announced that Hilary Robinson, PE, has joined the Leadership Team of the EBC Emerging Contaminants Working Group.

The members of the EBC Emerging Contaminants Working Group Leadership Team help to identify programming for EBC events.  Read more about the position, here.

The European Commission updated the Classification, Labelling and Packaging (CLP) Regulation on March 31, 2023, with the following hazard classes (link):

These new hazard classes for CLP of substances and mixtures were adopted on April 20, 2023. New substances on the market will need to be classified and labeled for these new CLP hazard classes by May 1, 2025, and new mixtures by May 1, 2026. Although the specific criteria for the new classifications have not been finalized, draft guidance with important details on the proposed classification scheme was released last month (link).

Complying with these new CLP hazard classes will require considerable effort and resources. Gradient scientists Dr. Tim Verslycke and Ms. Ari Lewis recently presented at PSX 2023 and PCPC 2023 on the likely impact of the new endocrine disruption classes and described a structured approach for screening ingredient portfolios to identify priorities, data gaps, and plan resources informed by prior project work on this topic. If you missed these talks or are interested in discussing further, please reach out.

To learn more about Gradient’s process for portfolio screening against the new CLP hazard classes or to have Gradient present to your company on this topic, please contact:

Tim Verslycke, Ph.D.

Ari Lewis, M.S.