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ToxStrategies Welcomes Dr. Rayetta G. Henderson and Ann Holbrow Verwiel

ToxStrategies is pleased to announce the addition of two health scientists, Dr. Rayetta G. Henderson and Ann Holbrow Verwiel.

Dr. Henderson – Research Triangle Park, North Carolina
Dr. Rayetta Henderson joined our team as a senior health scientist and is located in the Research Triangle Park, North Carolina area. She has managed scientific programs for the EU’s Registration, Evaluation & Authorisation of Chemicals (REACH) and Classification, Labeling, and Packaging (CLP) Regulations and has experience supporting trade associations in the development of strategies for addressing metal-specific issues related to REACH and CLP. In this role, she served as a scientific representative on a number of technical working groups, including legal and financial subgroups. She is knowledgeable of the UN’s Globally Harmonized System (GHS) including hazard assessment and classification for jurisdictions worldwide. Dr. Henderson has substantial experience designing, monitoring, and interpreting scientific data from toxicity studies and alternative method studies in support hazard evaluations.

Dr. Henderson has studied and performed health effects assessments on various chemicals including perfluorinated compounds (PFCs), dioxin-like compounds, and metals, particularly nickel and nickel-containing substances. Dr. Henderson earned her Ph.D. in Toxicology from the University of North Carolina at Chapel Hill, where her research focused on understanding the mechanism of action leading to the developmental toxicity of perflurooctane sulfonate (PFOS).

To read more about Dr. Rayetta Henderson and get her contact information, please visit her company web page.

Ann Holbrow Verwiel – San Francisco Bay Area, California
Ann Holbrow Verwiel joined our team as a managing health scientist and is located in our new San Francisco Bay Area office. She has more than 20 years of experience in environmental consulting in the areas of human health risk assessment, site assessment, and environmental regulation. Over her career, she has focused on integrating risk assessment into an overall risk management approach to problem definition, investigation, and mitigation. She has successfully applied this approach in negotiations with regulatory agencies and public groups to significantly reduce the cost/extent of investigation, assessment, and mitigation. She has published and presented papers on a wide variety of topics, including Monte Carlo analysis of the conservatism in risk assessment, environmental fate and transport of contaminants, and environmental auditing.

Ms. Verwiel has managed and conducted numerous human health risk assessments that addressed a wide variety of chemicals in soil, soil vapor, air, and groundwater. She has evaluated the chemical signatures, fate and transport mechanisms, and likely current and future human exposures as key first steps in the health risk evaluation. In the area of air toxics, she has worked to develop investigation strategies and perform assessments of exposure to indoor and ambient air that included emission source evaluation; modeling; and soil vapor, indoor air, and ambient air measurements. She also has assisted several entities with air toxic analysis to meet the requirements of Proposition 65, AB2588 Toxic “Hot Spots” Act, and the California Environmental Quality Act (CEQA). She has worked with regulatory public participation specialists, public affairs officers, and others to develop written summaries and presentation materials that convey complex technical issues to the public. She has provided litigation support for several projects, involving disputes between property owners and facility operators, alleged air emissions exposures, and Proposition 65 litigation.

To read more about Ms. Ann Verwiel and get her contact information, please visit her company web page.