Award winning toxin test receives international support
30 Aug, 2008
Source: IRL Innovate
A new method for testing marine toxins in shellfish has been validated for worldwide use by the IRL initiated Virtual Institute for Metrology in Chemistry & Biology and the Cawthron Institute.
The test was developed by four New Zealand scientists who won a Three Rs award this year, (which recognises work that helps replace, reduce and refine live animal subjects), for its potential use to replace mice that are currently used in shellfish toxin tests.
The new metrology-based test is a more accurate, efficient and sensitive method for detecting shellfish toxins than the existing method. The current method has been in use since the 1950s and involves mice of a specified body weight and large amounts of dangerous and difficult to use chemicals.
The new in vitro test uses voltage gated sodium ion channels (VGSC) from human skeletal muscle to test the safety of potentially contaminated shellfish and drinking water. When algal toxins bind to VGSCs they disrupt normal nerve and muscle function and can produce poisoning with neurological effects that range from irritated nasal passages and coughing to ataxia and paralysis.
Marine toxins are natural compounds produced by phytoplankton in the water, which shellfish consume. Neurotoxic shellfish poisoning is a syndrome caused by consuming shellfish contaminated by a class of these toxins, called brevetoxins.
Validation of the new test means it is now acceptable for worldwide use.
“Apart from ethical issues, this method has one main property which the previous assay doesn’t have – the ability to be validated and verified,” Paul McNabb of the Cawthron Institute explains.
“This is very significant for international trade because in a trade dispute over a mouse bioassay result it can’t be established whether or not the result is wrong. Whereas, if the test is based on metrology, it can be established through scientific investigation why something that has been certified as safe here in New Zealand has produced a different result in another country.”
Researchers at the United States Food & Drug Authority (USDA) are supporting its use as a total replacement for mouse tests internationally.
- 20 November 2008