Recent research has pointed to a possible risk factor for people who work with pesticides, this includes agricultural workers and people who spray pesticides on houseplants.

The study conducted by the Occupational and Environmental Medicine team at the Institute of Public Health, Epidemiology and Development in France, found the risk of getting a brain tumour was almost twice a high for individuals exposed to the highest amounts of pesticides, for example, agricultural workers. And there were even higher risks among this group, more than three times that of the general population, of a specific type of central nervous system tumour called a glioma.

They carried out their research in Bordeaux where there is widespread use of fungicides to protect grape vines. The research team were not able to gather data that would have enabled them to say, specifically, which pesticides were linked to the risk of getting brain tumours.

"The French study has identified an area warranting further investigation, however, we caution that the results should not be exaggerated," said Kathy Oliver, who is secretary of the International Brain Tumour Alliance.

She added: "It is important to emphasise that more research is required before people start throwing out their cans of household pesticides."

She further stated that: "Our organisation maintains contact with the world's leading specialists in brain tumours and unfortunately no single cause has yet been identified."

This viewpoint is supported by Cancer Research, UK: "More research is needed to confirm the observations made in this study as the results were based on people's recollection of pesticide exposure," says Josephine Querido, Cancer Research UK's science information officer.

"Brain tumours are relatively rare and, although workers exposed to high levels of pesticides in industry or farming may be at higher risk of certain cancers, current evidence is inconclusive and any risks are likely to be very small," she added.

A Crop Protection Association spokesman was more phlegmatic about the French team's findings, stating that: "Pesticides are some of the most thoroughly regulated chemicals in the world.

"There is no conclusive scientific evidence of a link between pesticides and brain tumours.

"This type of study does not demonstrate cause and effect, and the authors themselves admit that they did not identify which pesticides were used or the levels of exposure," he said.

Pharmaceutical International's Newsdesk