The Ministry for Primary Industries is to increase the heat on growers of crops that keep breaching the limits on chemical use.
MPI has released an update on its annual Food Residue Surveillance Programme.
In the past six months 250 samples of fresh, unwashed produce have been tested, including asparagus, eggplant, feijoas, hops, lemons, olive oil, persimmons, pumpkins, spring onions, sweet corn, tamarillos and walnuts.
Eleven of those failed to comply with maximum residue limits; they came from spring onion, asparagus, walnut, olive oil and tamarillo crops.
MPI food assurance manager Paul Dansted says he's pleased with the low level of non-compliance.
But he says he expects that figure to increase as the ministry targets more problematic crops.
Dr Dansted says the programme focuses on foods which are most likely to have residues.
"There are some kinds of crops that are more likely to collect residues, so you can imagine some crops are like an upside down bowl and when the crops are sprayed it tends to concentrate down the bottom, so those crops are more likely to have higher levels of residues", he says.
Dr Dansted says the ministry will release a final report in August.