Third 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 third quarter of the 2024 NZTDS included sampling and testing of 73 ‘national’ foods and ingredients, bought from Auckland supermarkets from October to December 2024. This included buying at least 4 units of 3 individual brands and compositing them for testing.
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 65,361 chemical tests, analysing 356 chemicals in a total of 1,372 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, selenium, sodium, thallium, and zinc. Foods and ingredients were prioritised for agricultural chemical and contaminant (including packaging chemical) testing.
Of the 58,449 agricultural chemicals tests reported, 99.8% 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 1,620 general element tests reported (aluminium, antimony, arsenic [total and inorganic], cadmium, lead, mercury [inorganic], thallium, and tin), the majority had levels below the LOQ. For those that were above the LOQ, we assessed none were an immediate food safety concern (see below for more details).
The majority of nutrient elements tests reported (iodine, iron, selenium, sodium, zinc) were within expected levels, and none presented a food safety concern.
Of the packaging chemicals bisphenols, BPA was found at levels lower than previously reported in New Zealand and it presents no safety concern. BPF and BPAF were detected in 2 foods at low levels that do not themselves present a safety concern. It is likely that these are being used as replacements to BPA. New Zealand Food Safety is evaluating the current science on BPA and its alternatives and will summarise our conclusions in the NZTDS final report.
Of the samples tested for the packaging chemical phthalates, 99.7% were below the LOQ. Those above the LOQ were within the safe range previously reported in a 2017 MPI survey.
All of the foods tested for 7 per- and polyfluorinated alkylated substances (PFAS) were below the respective LOQs.
Of the foods tested for contaminants, 2 ingredients and 2 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. 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, a raising agent called sodium aluminium phosphate (SAlP), which is used in baked products.
At the time, New Zealand Food Safety engaged with the baking industry to 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 quarter one. 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.
After the quarter one results, as a precaution, we engaged with the identified food businesses to phase out their use of additive 541. This work is continuing, and these food businesses 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 with this data to support a review. We will continue to engage with FSANZ on this matter.
Detailed results by chemical groupings
- Agricultural chemicals 1 [XLSX, 4.5 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, 252 KB]
Includes: a targeted multi-residue screen covering dithiocarbamate fungicides (expressed as CS2) and phenoxy and aromatic acid herbicides. - Contaminants [XLSX, 249 KB]
Includes: aluminium, antimony, arsenic (total), arsenic (inorganic), bisphenols, cadmium, DON, lead, mercury (total), nitrates and nitrites, PFAS, phthalates, thallium, and tin. - Nutrients [XLSX, 149 KB]
Includes: Iodine, iron, selenium, sodium, and zinc.
Disclaimer: Results may be subject to change. New results files will be uploaded and dated accordingly.
Fourth quarter sampling began in January 2025
The fourth quarter sampling round started on 20 January and ran to through to 31 March 2025. We collected 45 ‘regional’ foods and ingredients, bought from Auckland, Palmerston North, Christchurch and Dunedin.
The full dietary exposure assessment report is expected to be published mid-2026.
