Fruit sprayed with pesticide linked to food poisoning, claim scientists

Unwashed fresh fruit and vegetables sprayed with pesticide could be responsible for passing on food-poisoning bacteria, say Canadian researchers who found that dangerous bugs multiplied in the solutions sprayed on crops.

Unwashed fresh fruit and vegetables sprayed with pesticide could be responsible for passing on food-poisoning bacteria, say Canadian researchers who found that dangerous bugs multiplied in the solutions sprayed on crops.

Simple rinsing of produce under a tap "does little to remove harmful bacteria", said the scientist who led the research. He recommends a good scrubbing with soap and water.

Fears about such food-borne poisoning has recently led to a boom in domestic products that can thoroughly wash all sorts of vegetables and fruit - including hand-operated spin dryers to remove any trace of contaminants.

Such action is necessary because bacteria such as salmonella, listeria and E.coli 0157 can all thrive in the presence of some fungicides and insecticides that are officially approved for use on raw fruit, said Greg Blank and his colleagues at the University of Manitoba.

Dr Blank, of the university's department of food science, was intrigued by the growth in the number of cases of food poisoning attributed to fresh produce, New Scientist magazine reports today. So he set up an experiment to replicate the effect of a farmer using bacteria-contaminated water to mix his sprays.

The results were alarming: "Numbers [of bacteria] could increase one-thousandfold," he reported. The bacteria thrived on about one-third of the pesticides approved for use.

However, the Canadian work was criticised by Ross Dyer, the technical manager of the Crop Protection Association in Britain. He said that any such problem would be caused by the contaminated water - and that, rather than the use of pesticides per se, was the weakness. "If the water supply is contaminated, it's that that's supplying the bacteria in the first place," he said.

But Dr Blank said: "You have to be careful where you buy. Some farmers use green, uncomposted manure to fertilise fields. You don't have to be a rocket scientist to realise that that's going to lead to contamination." E.coli 0157, in particular, is passed on from animals' faeces and can cause kidney failure or even death in people.

Although Dr Blank has not concluded research to find out how long the bacteria survive in the food production chain, he is concerned enough that he treats all his vegetables with suspicion until they are thoroughly washed.