EPA Publishes Guidance on Surfactant Reference Values Based on New Approach Methods
The U.S. Environmental Protection Agency (EPA) recently published four documents relating to New Approach Methods (NAM) to the New Chemicals Division (NCD) Reference Library. The NCD Reference Library includes guidance documents, compliance advisories, templates, manuals, and other materials of interest for stakeholders wanting to understand the most up-to-date approaches for New Chemical assessment under Section 5 of the Toxic Substances Control Act (TSCA). Documents published to the NCD Reference Library are impactful, covering complex and often controversial topics.
The most recent tranche of documents posted to the NCD Reference Library encompasses NAMs for assessing potential human health hazards of surfactants:
- Reference Guide for Structural Classifications of Surfactants for Use in Determining if a New Chemical Substance is a Surfactant;
- Memorandum: Implementation of a New Approach Method for Human Health Risk Assessment for Surfactants;
- Data Evaluation Record for Triton X-100; and
- Data Evaluation Record for Oleoyl Sarcosine.
In these documents, NCD outlines a refined approach for inhalation risk assessment for surfactants using the MucilAirTM three-dimensional human airway epithelial model, which was favorably peer-reviewed by the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) Scientific Advisory Panel (SAP) in 2018. EPA derives human-relevant points of departures (POD) for respiratory irritation for two reference surfactants: the nonionic surfactant Triton X-100 and the anionic surfactant oleoyl sarcosine. The human equivalent concentrations (HEC) derived from the MucilAirTM assay will be used to assess portal-of-entry respiratory irritation for new chemical substances that are nonionic and anionic/zwitterionic surfactants. EPA also indicates in the implementation memorandum an intent to “continue to incorporate a broader range of structurally diverse surfactant analogues as human-relevant data become available.”
EPA has published cutting edge policy and guidance in the last year to the NCD Reference Library, including guidance on mixed metal oxides and a decision framework for hazard identification of skin irritation and corrosion. This library also includes key documents such as boilerplate language for TSCA Section 5 Consent Orders and common engineering default values used in New Chemical Assessments. There is currently no subscription or Listserv feature for the NCD Reference Library, though this feature has been requested, so for now stakeholders must keep a close eye on its webpage for future impactful updates from NCD.