Molecular study shows unexpected effects of toxin

Scientists from the University of Birmingham studying the effects of the widely-used pesticide fenitrothion, have discovered unexpected cell damage in a common freshwater fish, roach, exposed to the toxin. With colleagues from the universities of Exeter and Sussex the researchers exposed male roach to the pesticide for 28 days then studied the metabolites in their cells. Metabolites include fats, sugars and thousands of other natural chemicals - substances that can indicate whether a cell is healthy. The results did not show the expected neurological effects of fenitrothion on the roach, but revealed a host of other effects, including changes to the way steroids are metabolised. This suggests that fenitrothion is an endocrine disruptor - a so-called gender-bender which can affect an organism's sexual characteristics. The work reveals the range of effects this kind of exposure can have on non-target organisms, and it could help scientists develop effective 'environmental biomarkers' or indicators that show when toxic substances have found their way into the wider environment. This area of research - called metabolomics - has developed over the last decade as a new way of investigating the links between metabolic changes and an organism's health - for example, measuring cholesterol can provide an indication of heart disease in humans.