Bioaccessibility Research Canada (BARC) Guidance for Incorporation of Bioaccessibility Adjustments Into Risk Assessment.

The use of bioaccessibility in risk assessment is a useful tool that allows for a more accurate assessment of human health risk, but most jurisdictions in the world have not yet established guidance for the implementation of this tool. In Canada, a research consortium, BioAccessibility Research Canada (BARC), has been established that is addressing this need for guidance in Canada, and this presentation summarizes the activities undertaken since 2005. Over the years BARC has expanded to include international participants from Europe, the U.S. and Australia, and this has resulted in consensus-style collaboration between regulators, academia, and private industry. The main research needs identified in 2005 have been addressed and will be summarized, along with future plans for BARC. A guidance framework, which was one of the identified needs, has been developed for consideration by the bioaccessibility community. The guidance has proposed standardized definitions of terms used in the field, and consists currently of three parts: (1) a flowchart outlining the approach for using bioaccessibility and bioavailability into risk assessment; (2) checklists for bioavailability and bioaccessibility experiments, including methodological considerations such as liquid-to-solid ratios, grain size, pH and other factors influencing bioaccessibility estimates, and QA/QC requirements; and (3) a checklist of considerations for validation using in vitro/in vivo comparisons. As part of BARC initiatives, ESG has carried out a detailed literature review to identify data gaps and new areas of research in the field, and these will also be presented.