The first thing to note with this paper is actually found towards the end, and unfortunately not mentioned in the highlights, urinary levels indicate that exposures for these compounds are well below relevant exposure guideline values. This indicates that while the levels detected are elevated compared to some other countries there is no evidence that there is an immediate health risk.

The paper provides a range of results for different pesticide metabolites and presents evidence that food exposure may be the primary contributing factor to high levels of pesticide metabolites found in New Zealand children as compared to some other countries. Overall, the study provides important data for assessing the overall burden of pesticide exposure in New Zealand within a vulnerable population. It clearly highlights that New Zealand is not immune from chemical exposures being documented elsewhere and that exposure may be from more than just a “chemical event” such as spraying. Perhaps we all need to be more cautious about the chemicals we use including those we use in the home and on our pets. Good food and hand-washing practices are a good place to start.

More specifically, the authors note the difficulty in obtaining reliable data around pesticide use in New Zealand, a point also raised in the recent report by the Parliamentary Commissioner for the Environment. Such data would have enhanced the current study as it would have provided the authors an opportunity to clearly relate their study to pesticides used in high quantities within the study regions. Instead they have had to rely on a more generic screen which has indeterminate relevance to New Zealand agricultural practices. This means that determining the relevance of different exposure pathways (e.g. food vs direct spray contact) was complicated and less robust.

The authors articulate the limitations of the study, particularly noting that the use of urinary exposures as a measure of chronic exposure is not a precise exercise. Pesticides used currently are often excreted within 48 hours and there are many different variables involved that lead to significant variations between different people, even with the same exposure. Whether the numbers used in the study are sufficient to counter these effects, as the authors claim, is difficult to determine. The authors rightly suggest there is much more work that needs to be done to determine the full impact of the results presented.