Monitoring results show pesticides remain in food

This is the first report of the UK Working Party the Pesticide Residues (WPPR) published under the chairmanship of Prof Ian Shaw, Head of the Centre for Toxicology at the University of Central Lancashire.
    New features in the report are the chair's foreword and a useful and accessible summary dealing with the most frequently-asked questions about residues in foods, incorporating some of the findings of the report. These both help to give the report a more human feel.  There is also an extended introduction describing the background to residue work in Europe, sampling methods, quality control and the WPPR's programmes.
    Some of the WPPR findings will be familiar to those who follow these matters. Organophosphates in carrots have been in the news since unexpectedly high levels were found in individual carrot roots last year (see PN27 p3). Also surprisingly high levels of lindane were found in milk towards the end of 1995. This trend has since declined, but there is no explanation to hand for the elevated residue levels (see PN32 p14).
    There are other familiar issues. UK-grown lettuce continues to be a source of concern. "Several results were indicative of possible misuse, and there were several others where it was unclear whether approval conditions had been fully met." Four samples contained vincolozolin (not approved for use on lettuce and restricted because of reproductive toxicity to workers). One contained chlorothalonil and one carbaryl and five tolclofos-methyl (none of which are approved). Three residues of dithiocarbamates and three of iprodione exceeded the maximum residue levels (MRLs).
    The report notes with disappointment the continuing exceedances and evidence of non-compliance in using pesticides that are not approved. "There is no current risk to consumers but the risk is that consumers may draw their own conclusions-which may be to the detriment of the majority of UK growers because of the actions by a minority."
    Chlormequat, a growth regulator, was found in seven out of 21 UK samples of pears. It has approval for use on UK cereals, but not on pears. The residue findings therefore represent a strong indication of misuse.
    The food industry generates an increasing amount of monitoring data, fulfilling its duties under the Food Safety Act 1990. Or is it? The WPPR again records that some of the industry data was not supported by quality assurance data. There is no compulsion on industry to disclose data. Nor is it clear what are the standards of compliance. We do not know which retailers monitor adequately and which do not. If retailers wish to assure us of the safety of food they should be able to demonstrate this with the publication of residue monitoring results.

Annual Report of the Working Party on Pesticide Residues 1995, MAFF/HSE, HMSO, 1996, London,153pp.

[This article first appeared in Pesticides News No. 33, September 1996, page 27]