Expert panel to better understand endocrine disrupter low doses effects

Reproductive health / Risk, hazard and precaution

Environmental Sciences Manager Malyka Galay Burgos

Administrative Assistant Sonia Pulinckx

22-23 April 2013, Barcelona (Spain)

Background

In the field of endocrine disruption, the so-called “low dose‘ effects, non-monotonic dose responses (NMDRs), the existence or otherwise of toxic thresholds, mixture effects at low doses, and critical windows of exposure are challenging the current paradigm of toxicology and risk assessment of chemicals. Although the EFSA Opinion on the Hazard Assessment of Endocrine Active Substances (publ. 20 March 2013), and the earlier (June 2012, Parma) EFSA Scientific Colloquium on Low Dose Response in Toxicology and Risk Assessment, both suggest that there is no reason why endocrine active substances (EASs) should not be subject to risk assessment, the issues listed above imply a possible need to make modifications either to the risk assessment paradigm or to current test methods, or both. Furthermore, neither the EFSA Colloquium nor the more recent Workshop on Low Dose Effects and Non-Monotonic Dose Responses for Endocrine Active Chemicals (Sept. 2012, Berlin) were able to reach consensus about the importance, or even the existence, of these issues. This lack of consensus is partly due to uncertainty about the quality of data used to support these concepts, and partly due to a lack of understanding about putative underlying mechanisms of toxicity.

Aim

The aim of this workshop is to agree on a specific research programme which would be needed to achieve such a consensus and develop understanding of the implications for risk assessment of endocrine disrupters.

Terms of reference

The group will initially be formed by 14 members with representation from academia, regulatory authorities and industry. The purpose of this group would be to design and oversee the conduct and interpretation of a programme of experimental work to address the hypotheses that:

1. Endocrine active chemicals do not have a threshold below which adverse effects are seen and should be regarded and tested in a different way to chemicals acting through other modes of action.
2. At low dose / exposure levels, endocrine active chemicals exhibit non monotonic dose responses
3. When mixed at low doses, endocrine active chemicals produce effects greater than those which may be predicted from simple dose addition.

As an initial step, we would like to hold a meeting/workshop to agree on the concepts of the programme of work and how it could be best designed, conducted and managed to ensure that the outcome is both scientifically valid, and would be accepted as unbiased and as a significant scientific contribution to the field.