For many New Zealand families, Weet-Bix is one of those products that quietly sits in the background of everyday life.
It’s familiar. Trusted. Routine. Something dropped into bowls before school, with hot water and/or milk poured over the top almost automatically — or eaten later in the day with butter and Marmite as a quick snack or nostalgic treat.
That’s part of what makes these latest independent testing results so significant.
No More Glyphosate NZ recently submitted six Weet-Bix-style breakfast cereal products to Hill Laboratories for glyphosate residue testing using LC-MS/MS analysis. The purpose was not to create outrage or headlines, but to better understand whether similar supermarket products show meaningful differences in herbicide residue levels.
The results revealed substantial variation between products.
The Weet-Bix Products Tested
The following products were submitted for laboratory analysis:
- Weet-Bix Original
- Pams Wheat Biscuits
- Woolworths Wheat Biscuits
- Weet-Bix Gluten Free
- Weet-Bix Cholesterol Lowering
- Weet-Bix Multi-Grain
Some products were labelled as made in New Zealand, while others prominently displayed “Made in Australia” on the packaging.
At this stage, No More Glyphosate NZ has not independently verified the origin of the ingredients used in each product.
Weet-Bix Glyphosate Test Results
| Product | Glyphosate Level |
|---|---|
| Weet-Bix Original Batch A60602043 L1 – BB 01 Mar 2027 | <0.010 mg/kg (<10 ppb) |
| Pams Wheat Biscuits Batch A60630716 L1 – BB 04 Mar 2027 | <0.010 mg/kg (<10 ppb) |
| Woolworths Wheat Biscuits Batch A60561607 L1 – BB 25 Feb 2027 | <0.010 mg/kg (<10 ppb) |
| Weet-Bix Gluten Free Batch 006 20:0051 – BB 06 Oct 2026 | 3.9 mg/kg (3,900 ppb) |
| Weet-Bix Cholesterol Lowering Batch 1-22-07:47 – BB 02 Feb 2027 | <0.010 mg/kg (<10 ppb) |
| Weet-Bix Multi-Grain Batch 6040 02:05 2 41 – BB 09 Feb 2027 | 0.198 mg/kg (198 ppb) |
AMPA (glyphosate’s primary breakdown product) was below 0.05 mg/kg in all samples.
Glufosinate residues were below 0.006 mg/kg in all samples.
The laboratory reporting limit for glyphosate in this testing round was 0.010 mg/kg. “Non-detect” means any residues present were below the laboratory’s reporting threshold.
Weet-Bix Gluten Free Returned the Highest Glyphosate Result
Four of the six products returned results below the reporting limit.
One product — Weet-Bix Multi-Grain — returned a detectable glyphosate result of 0.198 mg/kg.
But the standout finding was Weet-Bix Gluten Free, which returned a glyphosate result of 3.9 mg/kg, equivalent to 3,900 parts per billion (ppb).
That result was substantially higher than every other product tested in this round.
Importantly, independent residue testing cannot determine the exact source of residues within a supply chain. It can only identify whether residues are present and at what concentration.
What these results do show, however, is that residue levels can vary significantly between products that many consumers may view as broadly similar.
Why Did Some Weet-Bix Products Test Higher Than Others?
One of the more interesting aspects of these findings is the contrast between products within the same brand family.
- Weet-Bix Original: below reporting limit
- Weet-Bix Cholesterol Lowering: below reporting limit
- Weet-Bix Multi-Grain: detectable glyphosate
- Weet-Bix Gluten Free: substantially elevated glyphosate result
Interestingly, not all Australian-made products returned detectable residues. Weet-Bix Cholesterol Lowering, which was also labelled as made in Australia, tested below the reporting limit.
That nuance matters.
The results suggest the differences may relate less to manufacturing location alone and more to ingredient sourcing, formulation, or agricultural practices linked to specific ingredients used within certain product lines.
One possible factor is the use of glyphosate-based herbicides as pre-harvest desiccants in some agricultural systems — a topic explored further in our articles on crop desiccation and glyphosate use in food production.
Gluten-free products, for example, often rely on different grains, starches, fibres, or imported ingredients compared with standard wheat-based cereals.
How Do These Glyphosate Results Compare With NZ Limits?
For comparison, New Zealand’s current glyphosate residue limit for wheat, oats, and barley intended for human consumption remains 0.1 mg/kg.
The detected levels in Weet-Bix Multi-Grain (0.198 mg/kg) and Weet-Bix Gluten Free (3.9 mg/kg) were substantially higher than that benchmark.
Questions around what constitutes a “safe” level of glyphosate exposure continue to be debated, particularly when considering long-term, low-dose exposure across multiple foods. How Safe Is Glyphosate in Our Food? Rethinking the Acceptable Daily Intake explores some of the questions increasingly being raised around ADI models and cumulative exposure assumptions.
Under the Trans-Tasman Mutual Recognition Agreement, food legally sold in Australia can also be sold in New Zealand — even when residue levels exceed limits that apply to some New Zealand-grown foods.
As more independent food testing emerges, questions around residue limits and long-term dietary exposure are receiving increasing public attention.
That’s why independently testing both local and imported food matters more than ever.
Still, the results raise broader questions about sourcing systems, agricultural practices, and how residue levels can vary so significantly between similar products sold side-by-side on supermarket shelves.
Why Independent Glyphosate Testing Matters
For years, much of the public conversation around glyphosate has remained highly abstract.
Terms like “acceptable daily intake,” “maximum residue limits,” and “regulatory compliance” dominate official discussions, while consumers are often left with little visibility into what residues may actually exist in everyday foods.
Independent testing helps bring some of that visibility back.
Not because one result alone proves harm, and not because all products within a category are necessarily the same, but because comparative testing can reveal patterns and differences that would otherwise remain invisible to the public.
One of the clearest takeaways from this testing round is that low or non-detectable glyphosate levels appear achievable within this product category. Four of the six products tested returned results below the laboratory reporting limit.
That raises an important question:
Why do some similar products carry substantially different residue profiles than others?
How the Weet-Bix Testing Was Conducted
- Samples were purchased through normal retail channels.
- Testing was performed independently by Hill Laboratories.
- LC-MS/MS analysis was used.
- Results are reported in mg/kg and ppb.
- Laboratory reporting limit for glyphosate: 0.010 mg/kg.
No More Glyphosate NZ did not seek formal comment from manufacturers prior to publication of this testing round. Previous enquiries regarding independent residue testing have generally resulted in responses emphasising that products comply with current regulatory requirements.
However, we welcome feedback or clarification from manufacturers regarding ingredient sourcing, agricultural practices, or testing methodologies relevant to these findings.
Will Future Testing Show Similar Results?
At this stage, these findings represent a single testing round.
Further testing — including repeat sampling across future batches — will help determine whether these results reflect isolated variability or a more consistent pattern over time.
But one thing is already becoming clear:
Consumers are increasingly interested not just in what food products contain, but how agricultural systems, ingredient sourcing, and processing practices may influence what ultimately ends up on supermarket shelves.
And those questions are unlikely to disappear any time soon.
Supporting Independent Food Testing in New Zealand
No More Glyphosate NZ’s independent testing programme is funded entirely by public support. We do not receive funding from government agencies, chemical companies, or the food industry.
Every donation goes directly toward laboratory testing to help expand transparency around glyphosate residues in New Zealand foods.
Donation options: https://nomoreglyphosate.nz/like-what-were-doing/
Important Testing Note:
No More Glyphosate NZ’s independent testing currently focuses on glyphosate, AMPA, and glufosinate residues. These tests do not screen for the many other pesticide, fungicide, insecticide, or agrichemical residues that may also be present in food products. Unless broader multi-residue testing is carried out, the full chemical profile of a product remains unknown.
Further Reading
Glyphosate in NZ Breakfast Cereals — Independent Test Results
A previous round of independent breakfast cereal testing that found detectable glyphosate residues across a range of mainstream cereal products.
Glyphosate in Bread: What Independent NZ Testing Revealed
A comparative look at glyphosate residues found in New Zealand supermarket bread products.
Why Glyphosate Isn’t Just a Weed Killer — It’s a Public Health Issue
An overview of why glyphosate remains one of the most debated chemicals in the modern food system.
Image Source & Attribution
The feature image on this page includes an original photograph provided by the No More Glyphosate NZ team. Who doesn’t remember eating Weet-Bix with butter and Marmite as a kid? This one brought back a few childhood memories around the NMGNZ table — although opinions remain divided on the correct butter-to-Marmite ratio.
