Washing fruit and vegetables does not remove chemical pesticide residues, tests commissioned by Government food watchdogs show. One chemical, which has links to cancer, birth defects and infertility, remained on the skin of apples despite the basic kitchen practice. Others remained both on the outside of potatoes and within the flesh, even after cooking.

The findings suggest that the most effective way to minimise the chemicals found on fruit and vegetables is to peel them. The Food Standards Agency insists that residues on fresh produce in the UK are so low that there is no need to wash them.

However, many people, particularly parents, take this step in what is now clearly the mistaken belief that it will offer added protection. At the same time, green campaigners insist there is a ‘cocktail effect’ of food crop chemicals on human health, even at low levels.

In tests, experts at the Agri-Food and Biosciences Institute in Northern Ireland examined whether food preparation and cooking were effective in removing a range of chemicals routinely used in growing and storing apples and potatoes.

The chemicals are used to stave off insects, fungus attacks and to stop some developing blemishes. Researchers looked at apples treated with the insecticide chlorpyrifos, fungicides captan and carbendazim, and antioxidant diphenylamine.

They found: ‘The residues of diphenylamine and carbendazim were not decreased by washing, but were decreased in the peel and core samples by cooking.’ Diphenylamine is not dangerous, however carbendazim is banned in the U.S. as it has been linked to cancer, birth defects and disruption of cell development.

It was banned from many food crops in the UK in 2006. Potatoes were treated with parasite suppressant oxamyl, sprout suppressant maleic hydrazide, post-harvest fungicide imazalil and post-harvest sprout suppressant chlorpropham.

The study found: ‘Washing decreased residues of imazalil and chlorpropham, but maleic hydrazide was not affected.’  When they were cooked in their skins, the experts found ‘some evidence of transfer of residue from peel to flesh’.

Imazalil has been identified by U.S. authorities as a cancer risk. Animal studies with chlorpropham found it caused inflammation of the stomach lining.

Campaigner Nick Mole, of Pesticide Action Network UK, said: ‘Repeated exposure to low doses and mixtures can have a deleterious effect on health, especially amongst the more vulnerable groups such as children.’

The FSA’s advice is that people wash fresh produce to ensure they are clean and free from germs, rather than because there is a need to remove residues. A spokesman insisted the public should not be concerned by the findings.

(By Sean Poulter, Daily Mail, 10/03/2012)