The UK Government’s Pesticide Safety Directorate found the following proportions of fruit and vegetables with detectable pesticides residues in UK supermarkets 1998-2000: Marks & Spencer 63%, Somerfield 59%, Sainsbury’s 49%, Asda 48%, Safeway 46%, Tesco 44%, Co-op 44%, Morrison 39%, Waitrose 29%. Most of the residues were within legal safety limits. Lettuce, grapes and strawberries, however, persisted in exceeding safety limits and containing residues of more than one pesticide.

Which? Magazine advised people to wash fruit and vegetables thoroughly, scrub root vegetables, discard outer leaves and not use peel or zest.

Ed.- Green Health Watch advises that scrubbing root vegetables is insufficient. All should be peeled. Even then, there are many ‘systemic pesticides’ which penetrate deep into the core of vegetables and fruit and cannot be removed.

The latest available figures* show that most outdoor salad crops grown in the UK are sprayed with one pesticide or another almost weekly during their ten to twelve week growing period: four insecticide, two fungicides and two herbicide applications. Often there are more: eleven to twelve applications are common.

Lettuce is on the Consumers Association (CA) ‘Persistent Offenders List’ for pesticides residues. In 2002 a CA survey found that half contained residues, nearly one in five contained levels above statutory maximums and a third contained residues of more than one pesticide. These levels were found in supermarket produce even though all of the external leaves (which contain most of the residues) had been removed when the lettuce was first picked and many more leaves had been removed in the packing factory.

* UK Government Central Science Laboratory 1999

Ed.- The nutritional value of a lettuce varies widely between varieties. Iceberg is the least nutritious, Romaine probably the most. As a general rule, the darker green the leaves, the more nutritious.