Fourth quarter results released in August 2025
The New Zealand Total Diet Study (NZTDS) aims to evaluate the risk to New Zealanders from exposure to certain chemicals, such as agricultural chemicals, contaminants, and nutrients in a range of foods most commonly eaten in a typical diet. The food, prepared as it would be consumed (for example, bananas are peeled, and meat is cooked), is then tested for the presence and levels of the chemicals, an estimate of exposure for certain population groups is determined, and the risk is estimated through comparison against health-based guidance values.
The fourth quarter of the 2024 NZTDS included sampling and testing of 45 ‘regional’ foods and ingredients, bought from Auckland, Palmerston North, Christchurch, and Dunedin food retailers from January to March 2025.
We tested the composite samples for a range of agricultural chemicals, contaminants (including packaging chemicals), and nutrients.
More information on the methodology can be found in the final project outline.
2024 New Zealand Total Diet Study (Infants and Toddlers) final project outline [PDF, 2.6 MB]
What we found
We conducted a total of 53,948 chemical tests, analysing up to 354 chemicals in a total of 736 foods and ingredients.
A general element screen was done on all foods and ingredients, including for aluminium, antimony, arsenic (total), cadmium, iodine, iron, lead, mercury (inorganic), selenium, sodium, thallium, and zinc. Foods and ingredients were prioritised for agricultural chemical and contaminant (including packaging chemicals) testing.
Of the 50,177 agricultural chemical tests reported, 99.5% had levels below the limit of quantification (LOQ). Of the very small number of detections above the LOQ, none were of a food safety concern.
Of the 1,260 general element tests reported (aluminium, antimony, arsenic [total], cadmium, lead, mercury [inorganic], and thallium), the majority had levels below the LOQ. For those that were above the LOQ, none were of a food safety concern.
Nutrient element results (iodine, iron, selenium, sodium, zinc) were within levels that we would expect and are in line with previous NZTDS findings.
Two food items were found to contain elevated levels of aluminium, which can be present in a range of products at low levels due to the use of a permitted food additive 541 (sodium aluminium phosphate or SAlP). New Zealand Food Safety has assessed the food safety risk as low because any risk can only emerge after high and consistent exposure over many years.
New Zealand Food Safety decided to include aluminium in the current study after the 2016 NZTDS identified elevated concentrations of aluminium in commercially baked goods. This was mainly due to permitted food additive 541, which is used as a raising agent in baked products.
At the time, New Zealand Food Safety engaged with the baking industry to voluntarily phase out additive 541, and our follow-up survey in 2019 found a significant decrease in aluminium concentrations in commercial bakery goods.
New Zealand Food Safety’s 2019 exposure assessment found that the high intakes identified in the 2016 NZTDS for the younger age group had been reversed. In addition, all population cohorts had exposures of below 50% of the health-based guidance value.
This showed our engagement with industry to phase out 541 had successfully mitigated the aluminium dietary risk from commercial bakery goods identified in the 2016 NZTDS.
The elevated levels of aluminium found in a small number of foods in this quarter’s results are in line with what we found in quarters one and 3. New Zealand Food Safety has assessed the food safety risk low because any risk can only emerge after high and consistent exposure over many years.
Since the initial results, as a precaution, we have engaged with the identified food manufacturers to phase out their use of additive 541. This work is continuing, and these manufacturers have committed to removing additive 541 from their products by early next year.
New Zealand Food Safety has also requested a review of the Australia New Zealand Food Standards Code permission for the additive 541 and has provided Food Standards Australia New Zealand (FSANZ) with this data to support a review. We continue to engage with FSANZ on this matter.
Bisphenols, per- and polyfluoroalkyl substances (PFAS), and the mycotoxin, deoxynivalenol (DON), were not found in any of the foods tested for these chemicals.
Of the samples tested for the packaging chemical phthalates, 99.2% were below the LOQ and those above were similar to a previous survey reported in 2017. These results do not present a food safety concern.
Detailed results by chemical groupings
- Agricultural chemicals 1 [XLSX, 2.4 MB]
Includes: a multi-residue screen covering a wide range of insecticides, fungicides, herbicides, and chemical groups such as organophosphates, organochlorines, triazoles, and neonicotinoids. - Agricultural chemicals 2 [XLSX, 239 KB]
Includes: a targeted multi-residue screen covering dithiocarbamate fungicides (expressed as CS2) and phenoxy and aromatic acid herbicides. - Contaminants [XLSX, 381 KB]
Includes: aluminium, antimony, arsenic (total), arsenic (inorganic), bisphenols, cadmium, DON, lead, mercury (total), nitrates and nitrites, PFAS, phthalates, thallium, and tin. - Nutrients [XLSX, 2.6 MB]
Includes: Iodine, iron, selenium, sodium, and zinc.
Disclaimer: Results may be subject to change. New results files will be uploaded and dated accordingly.
Four quarters of sampling and testing completed
The results of the fourth and final quarter of sampling and testing were released on 26 August 2025. The full dietary exposure assessment report is expected to be published in mid-2026.
