Pesticides Board responds to Sue Kedgley's claims

6 April 2000

The Registrar of the Pesticides Board, John Reeve, would like to clarify public statements made regarding pesticides residues found in New Zealand foods from the recently released 1997/98 New Zealand Total Diet Survey issued by Ministry of Health.

Sue Kedgley, in a recent Green Party Press release highlights the findings that 59 percent of the food surveyed contained pesticide residues - an increase of 3 percent since the previous 1990/91 survey. This is despite the report clearly stating that the survey was biased towards testing foods that were expected to contain residues, and that the increase in detecting residues from the samples can be attributed to the 10-fold improvement in the analytical methods used in the latest survey.

The report further states that the number of pesticides screened for had increased from 73 to 90, and that in 1997/98, only 20 pesticides were detected, whereas in 1990/91, 30 pesticides were detected.

In fact, as the report states, of the 272 samples with detectable residues, 160 of these would not have been detected by the less sensitive methods used in the 1990/91 survey, and the majority of the residues were at lower levels than those found in 1990/91.

"Further, Ms Kedgley highlights the finding of DDT residues in foods. DDT has been subject to very strict controls in New Zealand since the 1970's, and has essentially not been used in agriculture since that time. The residues found were at a level so low as not to constitute a breach of food regulations or pose a risk to human health. In fact, the levels were found at the lowest levels detectable and reflect a continuing downward trend of organachlorine residue levels in New Zealand food. The figure constitutes less than 1 percent of the internationally established acceptable daily intake," says Mr Reeve.

The Pesticides Board is keenly interested in the outcome of the Ministry of Health's investigations into finding the source of the DDT, but the finding of residues at the level of detection seems to indicate that any local use would not have been recent.

The Ministry of Agriculture and Forestry has been working closely with the poultry industry on a voluntary residue programme over the past two years, and this has not shown up evidence of any recent DDT use in New Zealand.

Ms Kedgley is also concerned at what she claims are "high levels of residues of the controversial dithiocarbamates in fruit and vegetables". The report clearly states that the exposure estimates used were worst case scenarios and possibly overestimated hazards by as much as three to ten-fold. Further, many crops (eg brassicas - such as cabbages) contain natural compounds that will interfere with the analyses, leading to an overestimate of the fungicide residue present. Despite these overestimates of the hazard, the New Zealand Total Diet Survey shows that the dietary exposure of New Zealanders to residues of dithiocarbamates is only 30 percent of the internationally acceptable daily intake. The report shows no residue increase of these fungicides since the 1990-91 survey.

The Pesticides Board is encouraged with the survey statement that said that the pesticide residue levels found in the 1997/98 New Zealand Total Dietary Survey showed dietary exposure estimates that are well within internationally established health standards and are therefore considered safe." Notwithstanding this, the Board will maintain the rigorous standards that it applies to applications for registration of pesticides in New Zealand to ensure that pesticides are used in a safe and prudent manner and pose no food safety risks to consumers.

The New Zealand Total Diet Survey was released on 30 March 2000.

For further information contact:

John Reeve, Agricultural Compounds and Veterinary Medicines (ACVM) Group, Ph 04 460 8733

Contact MPI

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