Human Exposure Task Force

The objective of the Human Exposure Task Force is to decide on exposure topics to be proposed to the ECETOC Scientific Committee (i.e. as ECETOC Task Forces or Cefic LRI activities), based on either topics already discussed during the Human Health Scoping meeting or any additional ideas emerging from other routes.

Background

There are increasing public and regulatory concerns regarding potential health risks posed by aggregate exposure, i.e. exposure to (the same) substance from multiple sources via multiple routes. The key questions are whether there is indeed any basis for consideration for aggregate exposure, whether the source-by-source approach can identify or miss significant risks to the environment and human health, and if so, when and by how much. Additional concerns relate to the fact that a substance and its diverse uses can be regulated under different legislations; the question is then how potentially identified risks from aggregate exposure could be best managed when the key exposure sources fall under different regulatory regimes.

Currently, these questions are addressed by following a tiered approach to aggregate exposure assessment (AEA). However, work undertaken in 2016 by the ECETOC TF on Effective Use of Human Exposure Data revealed that meaningful aggregate (consumer) exposure assessment is only possible with high tier approaches that rely on detailed (distributional) exposure factors data.

To further tackle this topic, a new Task Force on ‘Mid-tier approach to aggregated exposure assessment’ was formed in 2020; the Task Force intends to build on previous ECETOC work and explore suitable methodologies/tools for a mid-tier aggregate exposure assessment (AEA) that would determine the key exposure sources for a given substance, or whether a more detailed aggregate assessment would be useful.

Objectives

The new Task Force identified the following objectives:

  • Explore suitable methodologies/tools for a mid-tier AEA
  • Estimate reasonable worst-case or realistic AE
  • Criteria for the need and scope of a more detailed assessment
  • Address the complexities/uncertainties stemming from combination of different exposure assessment methods/tools, multiple lines of evidence and independent sources of information
  • Widen scope to products beyond cosmetics and food (e.g. household and DIY products, articles), investigate methodologies applicable to both consumers and workers

Deliverables

The Task Force aims to deliver the following:

  • A systematic evaluation of AEA methods, including comparative assessment of advanced mid-tier techniques vs the first-choice low-tier additive and high tier (probabilistic person-oriented) approaches
  • A framework for advanced/refined aggregate exposure assessment and practical recommendations for its application in the regulatory context
  • A peer-reviewed manuscript explaining the framework and demonstrating its utility and efficiency
  • A dedicated workshop for results dissemination and technical advocacy

The new Task Force’s work is expected to last between 24-30 months, finishing by the end of 2022.