Rodent Sperm Analysis: A rationale for and path toward acceptance and use in ecological risk assessment.

The Rodent Sperm Analysis method was devised some two decades ago to advance ecological assessment science for mammals, one of two groups of terrestrial receptors routinely evaluated at chemically contaminated sites. In part, this method recognizes that sufficient time has elapsed at sites, such that a need to anticipate or predict impacts to ecological receptors is an obsolete task. The method therefore, recommends evaluating the very receptors that occupy sites for evidence today of their displaying compromised reproduction, a toxicological endpoint of great concern within the regulatory community. Critically, Rodent Sperm Analysis is not a risk assessment method but rather a direct health status assessment method, a distinction that ecological risk assessors may fail to recognize or appreciate. Further, the method is not intended as a replacement for the conventional approach to ecological assessment, but rather a method to be run in tandem with it, where it may likely reveal that site mammals are commonly free of impacts and that conventional assessments are fully unnecessary. This Discussion paper is a cautious analytical review of ecological assessor perceptions about the vetted and recently ASTM International certified Rodent Sperm Analysis method. The review identifies potential impediments to the method gaining broader acceptance by professionals in the field, prominently among these, resistance to adopting a new ecological assessment paradigm that may be more helpful than the one presently in place.