Pesticides in fruit and vege

There are three main types of pesticides: herbicides, which kill weeds and other unwanted plants; fungicides, which kill fungi such as mildews and moulds; and insecticides, which kill insects.

The insecticides found in our test included organophosphates and pyrethroids. Organophosphates are one of the most controversial group of pesticides. They’re toxic to the environment, especially to insects, birds and aquatic life.

Pyrethroids are synthetic insecticides that disrupt the insect’s nervous system, leading to paralysis and death. There’s emerging evidence that pyrethroids may pose significant risks for our health and the environment.

No pesticide residues were detected in broccoli, capsicum, carrots, flat mushrooms, garlic and green kiwifruit.

Insecticides

Fungicides

Herbicides

Foods are allowed to contain pesticide residues up to the specified maximum residue levels. Under the Food Act, all food produced and sold must comply with the MRLs. However, exceeding the MRLs doesn’t necessarily mean a product will be removed from sale.

The Ministry for Primary Industries (MPI), which monitors pesticide residues in foods, said safety margins are incorporated into MRLs and considered there was no food safety risk from pesticide levels in the produce we tested.

MPI’s own food testing has detected some of the same pesticides in other produce. Interim results from its latest test round, published last year, reported 16 pesticide residues above MRLs in nine foods. These included several organophosphate pesticides banned in the EU: acephate in endive, diazinon in quince and methamidophos in Chinese broccoli.

While MPI considered none of the residues presented an “acute food safety risk”, acephate levels in one endive sample presented a risk of chronic exposure if the food was being regularly consumed. The grower no longer uses acephate.

Environmental effects are the other major concern with pesticides. Some pesticides we’re using are known to have significant environmental risks but research on their impacts in New Zealand is patchy.

A 2019 study, published in Environmental Pollution, measured pesticide concentrations in 36 streams in Waikato, Canterbury, Otago and Southland during the summer of 2017/2018. Three or more pesticides were found at 69% of sites and 30 sites contained chlorpyrifos, a pesticide banned overseas.

The Environmental Protection Authority (EPA) is responsible for approving pesticides and setting controls on their use. All pesticides used on fruit and vege must also be registered with MPI.

Growers must keep records of pesticide use. However, regulators don’t routinely monitor the volume of pesticides applied to crops so there’s little data about what’s happening on the ground.

In its 2019 Annual Report, the EPA acknowledged little was known about New Zealand’s chemical landscape or the impact it has on human and environmental health. It plans to develop a “chemical map” with information about what’s used and where, and evidence of harm.

In 2013, the EPA placed tighter controls on acephate, chlorpyrifos and other organophosphate pesticides in the face of mounting international evidence about their toxicity. However, according to MPI, some agricultural chemical suppliers and growers remain unaware of these changes and require “reminders”.

Regulators don’t routinely monitor the volume of pesticides applied to crops, so there’s little data about what’s happening on the ground.

Five organophosphates, including diazinon and methamidophos found in our test, are finally being phased out. From July 2023, methamidophos will no longer be able to be imported or made here. Diazinon has a longer phase-out period and will remain available until July 2028.

Four other pesticides in our test are on the EPA’s priority chemicals list for review. There are 39 chemicals on the list and the EPA expects to finish reviewing 25% during 2020. There’s no timeline for when other reviews will be completed, which means some chemicals banned in other countries could remain in use here for years.

The process for reviewing pesticides has come in for flak for other reasons. Victoria University environmental law expert Catherine Iorns believes it’s time to overhaul the rules.

In a 2018 article, published in the Environmental and Planning Law Journal, she argued the current system doesn’t include enough focus on adverse environmental effects and risks were assessed on a single chemical, rather than the cumulative effect of many pesticides.

“We still wait for proof of harm, and a lot of damage is and has been done before that harm is proven … there are no restrictions placed for the health of the ecosystem because we are waiting for that proof,” Ms Iorns said.

Internationally, there are also calls from scientists for tougher controls on pesticides. In January more than 70 scientists published a strategy for insect conservation and recovery, which included phasing out pesticide use.

We also tested imported organic and non-organic raisins. The Ministry for Primary Industries’ 2016 total diet survey reported raisins and sultanas contained the greatest number of pesticide residues.

We didn’t detect any residues in Ceres Organics Raisins or Sun Maid Natural California Raisins (both from the US). Seven residues were found in Cinderella Baking Raisins, though none were above the MRL. One (cyhalothrin) is banned in the EU.

• Ceres Organics Raisins (USA)
  No residues detected
  
• Sun Maid Natural California Raisins (USA)

  

  No residues detected
  

• Cinderella Baking Raisins (Turkey)
  Residues detected:
  • azoxystrobin 0.041mg/kg (MRL 0.9mg/kg),
  • cyhalothrin 0.055mg/kg (MRL 0.3mg/kg),
  • cypermethrin 0.026mg/kg (MRL 0.5mg/kg),
  • cyprodinil 0.095mg/kg (MRL 5mg/kg),
  • fludioxonil 0.034mg/kg (MRL 2.2mg/kg),
  • indoxacarb 0.085mg/kg (MRL 5mg/kg),
  • pyrimethanil 0.061mg/kg (MRL 5mg/kg)
    

Several members asked us to test rolled oats for glyphosate (aka Roundup) so we sent eight products to the lab.

Glyphosate wasn’t detected in six products including the four organic oats we tested: Ceres Organics Rolled Oats Jumbo, Chantal Organics Jumbo Rolled Oats, Harraways Organic Rolled Oats, The Commonsense Pantry Organic Coarse Oats, Uncle Tobys Rolled Oats Traditional and Creamy and Countdown Australian Rolled Oats.

However, two products – Harraways Oats Rolled Oats and Pams Rolled Oats – contained glyphosate residues above the MRL of 0.10mg/kg. Both had glyphosate levels approximately three times higher.

Both brands come from the same supplier. In response to our results, the companies conducted their own testing, which found eight products (with different production dates) had an average glyphosate level below the MRL (0.081mg/kg). Two products were above the MRL (0.11 and 0.15mg/kg).

Harraways chief executive Stuart Hammer said the company routinely tested glyphosate levels and past results found its oats fluctuated around the MRL. “Harraways has a process in place to supply glyphosate-free oats. In 2019, we asked our growers to voluntarily not use glyphosate on crops. However, for the 2020 season, growers have signed legally enforceable contracts not to use any form of chemical defoliant, including glyphosate,” Mr Hammer said.

Both companies anticipate their oats will be glyphosate-free by the end of 2020.

The Ministry for Primary Industries considered the levels of glyphosate we found “indicated no food safety concern”. In 2015 and 2016, it tested pea and wheat crops for glyphosate, and found residues in 26 of 60 wheat samples. Twenty were above the MRL though MPI considered there was “no food safety concern”.