Pesticide practice under the microscope
6 May 2008
A survey of a range of New Zealand produce has shown generally good pesticide practices were used when growing them. This year capsicum, strawberries, lettuce, mushrooms and courgettes went under the microscope.
The latest results from the Food Residue Surveillance Programme (FRSP), which looks at chemical residues found in fresh, unwashed produce, were released this week. Although some samples showed residues slightly over the permitted level, Paul Dansted, NZFSA Principal Advisor (Chemicals) says none of them represent any food safety or health concerns.
The annual FRSP targets between four and eight types of produce with the choice of crop determined by a range of factors. The foods are often varieties that authorities overseas have found to contain higher residue levels, or minor crops where growers may not have access to specific information about use of a particular agricultural compound on that crop. Dr Dansted says as the study focuses on areas where NZFSA suspects there might be problems, it is no surprise that non-compliant produce is sometimes found and he is pleased with the overall findings of this year's survey.
"Because the FRSP sets out to probe specific foods, for example those that may be problematic because they are susceptible to attack by pests or disease, it is more likely to identify problems than a purely random survey chosen from all foods. We are generally pleased with the result of this survey, but we fully expect that, from time-to-time, we will uncover problems that require corrective action. Only when such problems are identified can they be dealt with by education, regulation, sanctions or even legal action in extreme circumstances. In some cases a combination of these is required."
Of 36 samples of strawberries, there were four non-compliances. Two non-compliant levels of the chemical cyprodinil were found in two samples, one at 0.12 mg/kg and one at 0.13 mg/kg – only slightly above the maximum reside level (MRL) of 0.1mg/kg for this crop. Two non-compliant levels of the chemical fludioxinil, which also has an MRL of 0.1 mg/kg, were found in another two samples, one at 0.11 mg/kg and one at 0.12 mg/kg.
Of 24 samples of capsicum, three non-compliances were found. Iprodione with an MRL of 0.1 mg/kg was found in one sample at a level of 0.12 mg/kg. Propham with an MRL of 0.1 mg/kg was found in one sample at a level of 0.11 mg/kg. Methamidophos, which has an MRL of 0.2 mg/kg showed up in one sample at 0.39 mg/kg.
Of 24 fancy lettuce samples, two non-compliances were found. The chemical permethrin, which has an MRL of 0.1 mg/kg, was found at levels of 0.21 mg/kg and 0.30 mg/kg.
Of 24 samples of mushrooms, there was only one non-compliance. Prochloraz with a MRL of 0.5 mg/kg was found in one sample at 1.1 mg/kg.
None of the 24 samples of courgettes showed detectable residues for any of the compounds.
Dr Dansted says a dietary intake assessment of all non-compliant results has been conducted and the residue levels found in this year's problem crops pose no health risk to consumers. "These levels, although over the MRL, are well below that needed to produce any human health effects."
However, although the non-compliant samples are not a risk, Dr Dansted says work is going ahead to reduce the number of non-compliances. He says the study findings are used to inform growers about areas of concern and they enable NZFSA to discuss with the relevant sectors the best means of bringing the residue levels down to acceptable levels or to produce data that supports a new MRL. The individual growers are also told that problems were found in their crops, so they can improve their practices. "If we find problem crops we follow up again and if we find that it's the same growers that are the problem, we will take a much stronger regulatory approach," he says.
The Food Residue Surveillance Programme is one of NZFSA's ongoing monitoring programmes. It sits alongside the Total Diet Survey (TDS), which is carried out every five years to assess the public's exposure to a range of agricultural compound residues, selected contaminants and nutrients (eg, iodine) through analysing foods 'as consumed'. Another part of the suite of monitoring programmes is the National Residues Programme (NRP), which randomly samples animal products at the point of harvest for a wide range of contaminants and agricultural compounds. The Dairy Residue Monitoring Programme tests raw (unpasteurised) milk at the farm and before it's transferred to the tanker or dairy factory. The surveys together give a picture of what New Zealanders are exposed to through their food.
Resources available from www.nzfsa.govt.nz:
Agricultural compound residues in food
– common questions: