Exploring and understanding the toxicity of inorganic and organic contaminants

We were joined by Emeritus Professor Jack Ng from the Queensland Alliance for Environmental Health Sciences, the University of Queensland. Jack was the lead author of the NEPM guidance for industry on “Contaminant Bioavailability and Bioaccessibility”, and a contributor to several WHO, JECFA, and IARC monographs including the upcoming IARC monograph for the evaluation of PFOS and PFOA.

Jack spoke to us about the challenges of the complexity of exposure measurement in toxicity and risk assessment related to the internal dose, and the uncertainty dealing with exposure of multiple contaminants. Jack provided examples for validating new tools developed for assessing multiple contaminants. The IARC carcinogen evaluation framework will also be discussed using PFOS and PFOA as an example. Some of the key learnings were – the importance of internal dose assessment.  How bioavailability and bio accessibility provide a more refined risk assessment. Developing a new tool for safe cattle grazing on rehabilitated mine sites, and for assessing cyanide complexes in tailing dams.