U.S. EPA regulates chemicals in the United States through the Toxic Substances Control Act (TSCA), where new chemicals are added to the TSCA inventory through regulations in Section 5 of the Act, and chemicals already on the inventory are evaluated through regulations in Section 6. For both new chemicals and existing chemicals, a determination must be made as to whether the chemical poses an unreasonable risk to people or the environment. ToxStrategies uses our deep knowledge of toxicology and exposure sciences to help clients compile and analyze the information necessary for EPA to make determinations about their chemicals. Our approaches foster transparency, minimize delays, and provide EPA with the information needed to make informed decisions.
Chemical Hazard Assessment
- Systematic reviews of published literature to support hazard assessments
- Automated workflows for New Approach Methodologies (NAMS) for toxicity assessment
- Evaluation of in-vitro high-throughput screening assay data
- Toxicity test study design placement and monitoring, data management and interpretation
- Dose-response assessment
- Physiologically based pharmacokinetic (PBPK) modeling
- Weight of evidence analysis
- Epidemiology data assessment
Chemical Exposure Assessment
- Identify conditions of use
- Conceptual exposure model development
- Environmental fate predictions
- Predictive exposure modeling for conditions of use
- Compilation and analysis of occupational, environmental and consumer exposure measurements
- Identification of highly exposed and susceptible populations
- Biomonitoring data assessment
Regulatory Support
- PMN strategy and timeline development
- Data review and gap analysis
- EPA Interaction Support
- Response to agency questions
- Technical representation
- Support for consent order or SNUR discussions
- Preparation of Submission Documents
- Written narratives summarizing hazard and exposure information
- Response to comments
- Completion of PMN submission package
Models & Programs
- ChemSTEER
- E-FAST
- EPISuite
- OPERA
- Consumer Exposure Model (CEM)
- AERMOD
- AERSCREEN
- OECD Toolbox
- VEGA models
- GenRA
Section 5 Regulatory Submission Experience
- Pre-Manufacture Notification (PMN)
- Low volume exemption Applications (LVE)
- Significant New Use Notification (SNUN)
- Microbial Commercial Activity Notice (MCAN)
Section 6 Regulatory Support Experience (Scoping, Risk Evaluation and Risk Management)
- 1,3-butadiene
- Acrylonitrile
- Asbestos
- Formaldehyde
- Phthalates
- Phthalic anhydride
- Hexabromocyclododecane (HBCD)
Case Study #1: Significant New Use Notification (SNUN)
ToxStategies advised on a leachate experimental design and used the resulting data to perform a comprehensive evaluation of potential environmental releases and human exposures. We also used a weight-of-evidence approach to determine acceptable toxicity levels to humans as well as sensitive fish and land-based species. Risks to humans and the environment were then estimated and used to inform the EPA in their evaluation of a SNUN.
Case Study #2: Support for Existing Chemical Risk Evaluation
We have critically reviewed risk evaluations for various existing high priority chemicals. Our analyses of modeled and estimated chemical environmental releases, usage, and exposure, as well as derivation and choice of toxicity level (Existing Chemical Exposure Limit) have formed the basis for comments on draft risk evaluations. These important comments have been aimed at ensuring the best available science is used in assessing risk from high priority chemicals.
Case Study #3: Pre-Manufacture Notification (PMN)
Our firm has guided clients through the full spectrum of a PMN. Computational toxicological assessments of new chemicals and laboratory analyses have driven advice on cost-effective laboratory analyses. This information was then used to assess hazards and derive toxicity levels. Combined with our conceptual exposure model and exposure estimation, our client submitted a PMN request avoiding re-work and minimizing review times.