Michael Dourson has a PhD in toxicology from the University of Cincinnati, College of Medicine, and is a board-certified toxicologist (i.e., DABT) serving as the Director of Science at the 501c3 nonprofit organization Toxicology Excellence for Risk Assessment (TERA). Prior to this, he was Senior Advisor in the Office of the Administrator at the US EPA. Before this, he was a Professor in the Risk Science Center at the University of Cincinnati, College of Medicine and also worked at TERA and US EPA.
He has been awarded the Arnold J. Lehman award from the Society of Toxicology, the International Achievement Award by the International Society of Regulatory Toxicology and Pharmacology, and 4 bronze medals from the U.S. Environmental Protection Agency. He has been elected as a Fellow of the Academy of Toxicological Sciences (i.e., FATS) and as a Fellow for the Society for Risk Analysis (i.e., FSRA).
He has co-published more than 150 papers on risk assessment methods or chemical-specific analyses (4 of them winning awards), and co-authored well over 100 government risk assessment documents (many of them risk assessment guidance texts). He has made over 150 invited presentations to a variety of organizations, and has chaired over 150 sessions at scientific meetings and independent peer reviews. He has been elected to multiple officer positions in the American Board of Toxicology (including its President), the Society of Toxicology (including the presidency of 3 specialty sections), the Society for Risk Analysis (including its Secretary), and is currently the President of the Toxicology Education Foundation, a nonprofit organization with a vision to help our public understand the essentials of toxicology. In addition to numerous appointments on government panels, such as EPA’s Science Advisory Board, he is a current member on the editorial board of Regulatory Toxicology and Pharmacology and Human and Experimental Toxicology.
Current hazard identification practice and NAM research: Never the twain shall meet?
Scientists will occasionally (often?) lament the fact that traditional risk assessors do not use their cutting edge, non-animal, data in evaluations to protect the public from various chemical risks. But why should they do so? Risk assessors know that some critical effects found in experimental animals cannot easily be determined with non-animal data, e.g. reduced body weight. Furthermore, assessors are often reluctant to go with only non-animal data because protecting the public health is done with an abundance of caution and they are comfortable with what is known to be generally protective.
So how does one bridge the gap? Two possibilities, and perhaps others, exist. The first stems from the well-established recognition that environmental chemical mixtures cannot be easily evaluated with experimental animals, in large part because the mixtures are highly varied and changeable. In contrast, non-animal data can be used to “fingerprint” a chemical or mixture with well-established experimental animal data and this fingerprint can then be compared to fingerprints of other chemicals or mixtures without such experimental animal data to gauge their overall toxicity. The second approach is to use existing non-animal data as a means of evaluating the mode of action for the critical effect of any chemical. The use of such data is now well established in the risk assessment community for some non-animal data and new non-animal methods will only enhance this evaluation.
So what are the steps forward? There are likely several. However, an easy one is to invite traditional risk assessments scientists to become familiar with the types of non-animal data that may be of some use in the in their own evaluations. Such invitations will likely make them more comfortable with these data and allow them to make suggestions for improvements on future non-animal testing.