Endocrine Disruption and Environmental Pollution
Chemicals such as those that form part of cosmetic and toiletries products, medicines and household products are required by laws in the US, Europe and Japan to be tested for their ability to disrupt the hormonal systems of mammals. Chemicals that have these effects are often referred to as 'gender bending' chemicals but here we refer to them as endocrine disruptors (EDs).
Under the European Chemicals Policy and the commensurate Registration, Evaluation and Authorisation of Chemicals (REACH) system, both in vivo and in vitro methods are proposed for testing chemicals for their ability to cause endocrine disruption.
Three in vivo assays are currently being considered by the OECD as tests for endocrine disruption. These can require the use of large numbers of animals. The first is the rodent Hershberger assay to detect chemicals that have the potential to act like, and consequently interfere with, endogenous male sex hormones. The second is the uterotrophic assay that measures the effects of chemicals on female rodents. The final assay involves tests conducted on amphibian metamorphosis.
FRAME works with the US Environmental Protection Agency to ensure that in vitro cell-based tests are used to their full potential and to ensure that any in vivo tests are used as a last resort. Part of this work involves looking at the validity of each type of assay and the relevance to humans.