Endocrine Disruption Evaluation

ToxStrategies consulting professionals have the scientific expertise and experience necessary to characterize the potential for a substance to have endocrine-disrupting properties. Applications include chemicals associated with personal care products, food-contact materials and food ingredients, pesticides, and industrial chemicals. We have a working knowledge of both the US EPA Endocrine Disruptor Screening Program (EDSP) and the guidance that was developed jointly by the European Chemical Agency (ECHA) and European Food Safety Authority (EFSA) on the identification and assessment of potential endocrine disruptors (EDs). Recognizing the ever-evolving nature of the field, including the varying approaches to characterization and regulatory requirements world-wide, our goal is to provide fit-for-purpose analyses that assess and differentiate potential endocrine signals in the context of hazard and risk assessments.

With our primary goal of meeting the specific needs of our clients, ToxStrategies consultants can work in a partnership role with your existing scientific staff, or in cases where companies do not have an in-house group of scientists, we can serve as your go-to resource. We are also available to provide representation to regulatory authorities on endocrine-disruptor issues. Following are examples of ToxStrategies professionals’ extensive experience with evaluation of potential substance-specific endocrine activity.

Identification and Appraisal of ED-Relevant Information

• Targeted literature search using syntax developed in-house for public and proprietary databases
• In-house database toolbox, including public and proprietary literature (e.g., PubMed, Embase) and knowledge (e.g., ToxPlanet, FDA EDKB) databases
• Identification of validated guideline studies relevant to human health and environment/ecotoxicity (OECD Conceptual Framework GD 150)
• Identification of epidemiological data, including field studies and population models
• Curated mapping and mining of high-throughput database assays (i.e., ToxCast/Tox21)
• Categorization of ED-relevant studies and endpoints by assay category and endocrine pathway ( i.e., estrogen [E], androgen [A], thyroid [T], and steroidogenesis [S])
• Established workflow that uses templates for data extraction by lines of evidence (including published ECHA templates)
• Critical appraisal tools for assessment of in vitro, in vivo (mammalian and wildlife studies), and epidemiological data

Evaluation of Potential Endocrine Disruption

• Assessment of activity and adversity within and across E, A, T, and S pathways
• Hazard identification of ED properties via guidance adopted by ECHA and EFSA
• Characterization of adverse outcome pathways for ED; including effects on reproduction and development, thyroid function, endocrine-related tumor types
• Hypothesis-driven weight-of-evidence analysis for relevant endocrine pathways/modalities for assessing potential activity in humans or wildlife
• Mode-of-action and/or adverse-outcome pathway analysis to assess the biological link between adverse effects and ED activity
• Weighting on endpoint-outcome relevance
• Evaluation of contextual data, such as toxicokinetics, for interpretation of endocrine pathway homeostasis
• Application of various ED frameworks (e.g., Other Scientifically Relevant Information [OSRI] used within EPA) to characterize ED properties
• Identification of incomplete data sets and prioritization of data gaps and testing modes

Screening and Testing Chemicals for Potential Endocrine Disruption

• Strategic assessment and/or development of test guidelines and testing needs (e.g., US EPA OCSPP Series 890 TG, OECD TG 150)
• Determination of and support for identification and/or opting out of specific testing
• Assessment compatibility of published studies to guideline testing protocols
• Predictions from QSAR or “read across” based on data on similar chemicals
ToxStrategies consultants also design, implement, and oversee ED testing programs across in vitro and in vivo studies (mammalian studies and studies in wildlife) within US EPA’s EDSP tiered program, and levels of methods identified in OECD GD 150:
• Assist with placing studies based on qualification of contract research organizations (CROs)
• Monitor studies in vivo and in vitro (mammalian and in wildlife)
• Coordinate test-chemical information and analysis
• Dose and/or concentration selection for screening and testing protocols; design of dose/concentration range-finding studies
• Data review and interpretation in the context of evidence base

For more information about our services, please contact us.