Over the past decade, the Spanish slug Arion lusticanus has been invading central Europe, displacing indigenous slugs and destroying crops.
But the physiology of the slimy aggressor could prove to be literally one in the eye for drug testing, according to Belgian research.
Els Adriaens and Jean Paul Remon, from the laboratory of pharmaceutical technology at the University of Ghent, have shown that these slugs provide a reliable alternative for the Draize eye test, in which rabbits are used to test the irritancy of substances.
The team was investigating the irritation potential of ingredients added to drugs to improve their absorption through mucus walls, such as the eyes, cheeks, nose and lungs.
Dr Adriaens began experimenting with slugs because their bodies are covered in a membrane very similar to that in the human nose. The effects of the irritants are easily observed as they occur on the outside of the slug. She said the results of the slug irritancy tests compared well with those on rabbits, dogs and humans. "There is a good chance that the mucosal irritation test could replace eye testing on animals."
The test could be ready for laboratory use by next year. The procedure was recently granted a patent in the US and there has been considerable interest from pharmaceutical companies.
Dr Adriaens said that her work had been positively received despite some public aversion to animal experiments. "The slugs I use come from gardens and people are happy that I take them."
A spokesman for the British Union for the Abolition of Vivisection described the use of any animal as "morally unacceptable".
* The number of animals used in scientific procedures is at a 45-year low, according to government figures. In 2001, there were 2.62 million procedures on 2.57 million animals, a 3.4 per cent decrease on 2000. Most procedures were for breeding, basic research and applied research, including drug testing.