Current legislation dictates that animal test data is
still required to help assess potential health hazards of chemicals to humans. Although there are valid
arguments either way concerning the extrapolation of animal data to humans and whether alternative methods of assessment are
acceptable, the fact remains that animals are unfortunately required in many cases for regulatory assessment.
Progress has been made in recent years to reduce the numbers
of animals required during testing and in vitro test data is now more widely accepted in many cases.
There is also progress in computer modelling and recognition in the importance of reading across data within groups
of chemicals. Under the 'old' European system, the Dangerous Preparations Directive makes
it clear that mixtures should be classified by calculation and not by performing animal tests on mixtures. The new European
REACH and CLP Regulations take this further and require approval to be obtained from ECHA, the European Chemicals Agency,
before any animal tests are carried out, for both substances and preparations. Approval for new testing on animals will
only be granted once all other methods to generate the necessary data have been exhausted.
Denehurst supports the development of alternatives to animal testing
and has over the years successfully made the case to use old non-regulatory data, read-across methods, modelling assessment
or to use protocols that require fewer animals. Animal testing must only be performed when all other options
have been explored and even then, the study design must take into account animal welfare. Denehurst will
not support animal testing that has not been demanded by a regulatory agency and where alternative methods have not been attempted.
The concerns of Denehurst reflect current
legislation in Europe and contrary to the views of many who protest against animal testing, there are very strict rules on
the use of animals in scientific procedures.
- A permit (licence) must be obtained from an Government
Agency (eg UK Home Office) before animal testing can be performed. Premises will be inspected without prior
warning and personnel must be suitable qualified. The named licence holder is legally responsible and can
be subject to criminal proceedings if the conditions of the licence are not met.
- Tests that
deliberately lead to death as an end point are not permitted. The LD50 test is banned in Europe
and alternative non-lethal end points are used for classification.
- Maximum permitted dose levels reflect those of classification
end points; for example, acute oral testing is limited to 2000 mg/kg, longer-term toxicity testing to 1000 mg/kg/day and fish
toxicity to 100 mg/l.
- Preparations calculated to be hazardous by the Preparations Directive cannot be tested, unless there is concern that
the hazardous properties have been enhanced by mixing; for example, plant protection products are formulated with solvents
and surfactant to improve efficiency and calculating health effects is not possible.
- Repeating previous work is not permitted and test
laboratories must demonstrate that reasonable efforts have been made in finding out if previous testing has been performed.
For new substances, an ‘Article 15’ enquiry to the regulatory authorities must be made to ensure that the
substance has not been previously notified.
- Skin and eye irritation studies are not permitted on animals if the pH is <
4 or > 11 and if in vitro testing indicates that classification is required. Only substances
that appear non-hazardous following in vitro testing can be tested to confirm the non-hazardous classification; even
then, only one animal should be initially tested and a maximum of three animals should be used.
- Fish are vertebrates and are covered
by animal test regulations
- Cosmetics or chemicals to be used only in cosmetic or other personal care products cannot be tested on animals.
It should be remembered that animal testing is very expensive
and even if there was no legislation restricting this work and even if chemical suppliers had no concerns about animal welfare,
it does not make economic sense to perform unnecessary studies.
The UK has probably the most carefully controlled legal system for animal welfare in the World and goes beyond minimum
requirements set out by EU legislation. UK laboratories have consistently led the way in animal welfare,
environmental enrichment for animals, and in finding alternatives to the use of animals in scientific procedures.
In the US, for example, higher dose
levels can be used and LD50 testing is still permitted. In many cases, it is also expected that
mixtures and preparations are tested instead of calculating effects. This reflects the regulatory
demands set by the US Government and does not necessarily reflect welfare concerns by US chemical suppliers.