Key Opportunities to Replace, Reduce, and Refine Regulatory Fish Acute Toxicity Tests.

Natalie Burden,James R Wheeler,John Handley,Mark Clook,Audrey Pearson,Kate Benyon,Neil Harper,Rachel Benstead,Thomas H Hutchinson,Kathryn Ryder,Roger Van Egmond,Christopher Green,Samuel K Maynard,Dave Sheahan,Chris Mead

doi:10.1002/etc.4824

Abstract

Fish acute toxicity tests are conducted as part of regulatory hazard identification and risk‐assessment packages for industrial chemicals and plant protection products. The aim of these tests is to determine the concentration which would be lethal to 50% of the animals treated. These tests are therefore associated with suffering in the test animals, and Organisation for Economic Co‐operation and Development test guideline 203 (fish, acute toxicity) studies are the most widely conducted regulatory vertebrate ecotoxicology tests for prospective chemical safety assessment. There is great scope to apply the 3Rs principles—the reduction, refinement, and replacement of animals—in this area of testing. An expert ecotoxicology working group, led by the UK National Centre for the Replacement, Refinement and Reduction of Animals in Research, including members from government, academia, and industry, reviewed global fish acute test data requirements for the major chemical sectors. The present study highlights ongoing initiatives and provides an overview of the key challenges and opportunities associated with replacing, reducing, and/or refining fish acute toxicity studies—without compromising environmental protection. Environ Toxicol Chem 2020;39:2076–2089. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Highlights

Employed in the nineteenth century as a forensic tool for investigating fish kills from effluent pollution, fish acuteApplying the 3Rs in fish acute toxicity tests—Environmental Toxicology and Chemistry, 2020;39:2076–2089Industry sector Plant protection productsIndustrial chemicals Biocides RegionExample legislationAcute in vivo test required for active substances Species required/recommended, and product/(yes/no) formulation testing requirements EUEuropean Commission (2013) Yes
Many regulatory regimes require ecotoxicity data across 3 trophic levels, conducting tests using nonvertebrate species first may provide sufficient information for safety assessment when considered with other data, if the chemical falls into a class where potential toxic effects are well known
Conduct retrospective data analysis comparing the acute toxicity of a range of different formulation types with the same active substance tested in the same species, to determine whether there are any patterns and if any general rules can be established

Summary

Introduction

Employed in the nineteenth century as a forensic tool for investigating fish kills from effluent pollution, fish acuteIndustry sector Plant protection productsIndustrial chemicals Biocides RegionExample legislationAcute in vivo test required for active substances Species required/recommended, and product/(yes/no) formulation testing requirements EUEuropean Commission (2013) Yes. The European Union's Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) regulation for industrial chemicals uses a pseudo‐exposure‐driven approach because only substances produced or imported over 10 tonnes/yr require fish acute toxicity data (Table 1).

Results

Conclusion