Commentary: Setting Aside Tradition When Dealing with Endocrine Disruptors

Abstract

In 1996, the US Congress directed the Environmental Protection Agency to produce screens and assays to detect estrogenic and other endocrine-disrupting chemicals in food and water. To date, there are none. Years have been wasted in attempts to utilize traditional toxicological approaches to solve the problem, when in retrospect, it is now apparent that the delay in part stems from the reluctance to attack the problem with entirely new approaches. To develop new testing protocols, it is necessary to set aside much of the dogma of toxicology and to begin again with open minds. A few pertinent examples are provided concerning what has been overlooked and what needs to be done. In particular, it is necessary to give close attention to the selection of animal strain and diet, factors that were only loosely controlled historically when one takes into consideration what has been learned in the last decade. Vast numbers of animals have been sacrificed, and more will be sacrificed, in futile attempts to validate assays and to develop safety standards unless knowledge gained over the past decade concerning the sensitivity and complexity of the endocrine system is taken into consideration.

How isoflavone levels in common rodent diets can interfere with the value of animal models and with experimental results

“…However, when dealing with models used in endocrine disrupter studies such as the uterotrophic assay, numerous scientists have urged for caution and recommended paying attention to isoflavones in the diet (Kanno et al 2002, Thigpen et al 2002, Colborn 2004, Stokes 2004. The rodent uterotrophic bioassay is used in the determination of oestrogenic or antioestrogenic potential of chemical compounds.…”