Oral Presentation SETAC Asia-Pacific Virtual Conference 2022

Performing Environmental Risk Assessment for Potentially Persistent, Bioaccumulative, and Toxic Substances (#66)

Huiting Chen 1 , Gail E Bragin 2 , Craig W Davis 2
  1. ExxonMobil (China) Investment, Shanghai, SHANGHAI, China
  2. Environmental Science, ExxonMobil Biomedical Sciences, Inc, Annandale, New Jersey, US

PBT/vPvB substances are not easily degraded in the environment and have the potential to accumulate in organisms. They have attracted widespread attention in chemical management in various countries. P, B and T are all properties which can elevate concern for chemicals due to their potential to cause risk in unintended and/or specific manners. To address these concerns, criteria to identify chemicals with PBT properties have emerged, which over time has led to different regional approaches to management. These approaches range from strict categorization-based approaches, defining such substances as “high concern” to be restricted, to their use in prioritizing the conduct of higher-tier evaluations that include exposure from specific use scenarios to make decisions based on risk. Quantitative risk assessment can actually be performed for PBT and vPvB substances to assess the risk to aquatic life and exposure to man via the environment. P, B and T attributes, such as half-lives, BCF and BMF should be explicitly accounted for in quantitative exposure assessments that comprise a risk assessment. A well-defined and unambiguous scope and systematic approach to risk assessment can help assessors and regulators to quantify chemical risk in a confident and efficient manner as well as to identify and prioritize additional higher tier chemical information needs. This presentation will discuss the challenges associated with P, B assessment and recommend the use of weight of evidence approaches to fully consider the attributes of the chemical substance itself and the risks brought by possible exposure in order to achieve effective management of potential PBT chemicals.