A welcome end to notorious tests

Monday, 28 September 2009 13:04

Advocates for Animals has welcomed the news that non-animal methods to replace the Draize rabbit test for severe eye irritancy have now been accepted by the Organisation for Economic Cooperation and Development (OECD).

At last, guidance is in place on how to conduct the tests without using live rabbits - meaning that thousands of rabbits will be spared procedures where chemical substances are applied to their eyes.

Since 1944, the Draize rabbit eye irritation test has been the standard method for evaluating the ocular irritation/corrosion potential of a substance for regulatory purposes. Adult albino rabbits are most commonly used for eye irritancy tests because they have eyes with a large surface area. At least three animals are used per test substance. The test involves applying the substance directly into one eye (the other eye acting as a control) and observing effects for up to 21 days. Effects can include swelling, soreness and weeping eyes.

Now, two test-tube methods for assessing eye irritation have been accepted by the OECD, the BCOP (Bovine Corneal Opacity and Permeability) test and the ICE (Isolated Chicken Eye) test, both for identifying ocular corrosives and severe irritants.

Whilst the Draize test will continue to be conducted for substances that are not severe eye-irritants, the OECD’s decision does mean that many thousands of rabbits will be spared distressing and painful tests that have been scientifically criticised for many decades for poor reproducibility and species differences between rabbits and humans.

Some 4,500 rabbits are used in eye irritancy tests in the European Union each year. Global use is likely to be considerably higher.

It has taken at least thirty years for alternative tests to be approved, with research starting in the 1980s, scientific approval by the European Centre for the Validation of Alternative Methods (ECVAM) coming in 2007 and now OECD acceptance in 2009 meaning that the test can be used globally. Early-stage research work in the 1980s, funded by the Dr Hadwen Trust, has now resulted in one of the replacement methods approved.

Advocates for Animals agrees, however, with the comments made on its website by Dr Hadwen Trust :“It is highly regrettable that it has taken some thirty years to achieve international acceptance of these replacement solutions. Whilst funding, industry support for alternatives and consequently the speed of method development has significantly improved in recent years, unnecessary delays in the validation process remain a problem.

“A particular issue is that animal test data are still treated as the ‘gold standard’ against which alternative tests are compared in order to achieve scientific validation. However when animal data are of such poor and variable quality such as the rabbit eye test, the process of replacing scientifically weak animal methods can be delayed by years.”

(Information drawn, with thanks, from Dr Hadwen Trust)