Reducing repetition of regulatory vertebrate ecotoxicology studies

A significant number of regulatory ecotoxicology studies currently carried out do not comply exactly with the corresponding OECD Test Guideline, resulting in uncertainty for the regulatory decision makers evaluating the studies. This may ultimately result in requests for repeat testing, including repetition of vertebrate tests. We are leading a project which aims to determine which deviations fundamentally undermine study endpoints, and which deviations do not impact on the scientific quality of studies. This will involve both scientific and historical analysis of the technical requirements included within vertebrate Test Guidelines, and consultation with a broad range of experts in the field. The analysis will inform recommendations on the critical factors that influence overall test performance. This work is being guided by an expert Working Group comprised of international representatives from 12 organisations across governmental regulatory bodies, academia and the chemicals industry.

We have conducted surveys  to collect information on the most commonly conducted Test Guideline studies, the deviations to technical requirements encountered most frequently, and which deviations are currently tolerated before the results of a study are no longer deemed scientifically robust. They were open to contract research organisations conducting vertebrate ecotoxicology studies; companies sponsoring vertebrate ecotoxicology studies; and regulatory authorities assessing submissions containing data from vertebrate ecotoxicology studies. The data will be used to prioritise which Test Guidelines and technical requirements are taken forward for in-depth analysis. 

The intention is that the findings of this project will form the basis of regulatory guidance to support regulators, study sponsors and study directors. Such guidance has the potential to decrease the number of requests for repeat in vivo studies, and to simultaneously increase the scientific robustness of required in vivo tests.


A poster on this work was presented at the NC3Rs Toxicology Showcase in September 2016: Reducing repeat testing of regulatory vertebrate ecotoxicology studies through a critical assessment of Test Guideline criteria.

Burden N, Gellatly N, Benstead R et al. (2017). Reducing repetition of regulatory vertebrate ecotoxicology studies. Integrated Environmental Assessment and Management, 13(5):955-957. doi: 10.1002/ieam.1934

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