What happens when we test supermarket bread more than once?
When we first tested supermarket bread for glyphosate residues, all samples returned “none detected” at the reporting limits used by the lab (0.05 mg/kg). While that was reassuring at face value, it also left an important question: were residues truly absent, or simply below the level being measured?
To explore that further, we arranged a follow-up round of testing using a lower reporting threshold of 0.01 mg/kg (10 ppb). That second round revealed something different. While some samples still showed no detectable residues, others did.
With that in mind, we commissioned a third round of testing and selected a fresh set of samples from a range of well-known brands. The aim was not to prove a point, but to see whether those earlier findings reflected a one-off outcome or something more consistent.
This latest testing included eight commonly available breads from different brands and batches, all drawn from the same everyday food category that most households rely on.
Glyphosate test results in NZ bread — same shelf, different outcomes
These results come from the third batch of supermarket bread testing. By this point, the question had shifted from whether glyphosate could be detected to whether the mixed results seen previously would show up again.
| Bread Sample | Glyphosate Level |
|---|---|
| Freya’s Tusan Mixed Grain Batch AD1 1900 BB 29 Mar 26 | 0.21 mg/kg (210 ppb) |
| Burgen Superb Soy & Linseed Batch AK5 082 20:07 BB 29 Mar 26 | 0.168 mg/kg (168 ppb) |
| Woolworths Essentials Wheatmeal Batch AK3 083 4:32 BB 29 Mar 26 | Not detected |
| Tip Top Supersoft Batch 081 BB 28 Mar 26 | Not detected |
| Burgen Mixed Grain Batch AK5 081 18:56 BB 28 Mar 26 | 0.044 mg/kg (44 ppb) |
| Vogel’s Sunflower & Barley Batch AD6 0402 BB 28 Mar 26 | 0.024 mg/kg (24 ppb) |
| Vogel’s Original Mixed Grain Batch AD6 0207 BB 29 Mar 26 | 0.033 mg/kg (33 ppb) |
| Vogel’s Harvest Grains (Sprouted Whole Grains) Batch AD6 0324 BB 28 Mar 26 | 0.023 mg/kg (23 ppb) |
Two samples showed no detectable glyphosate. The remaining six contained measurable residues, ranging from 0.023 mg/kg to 0.21 mg/kg.
The samples were also screened for AMPA (a primary breakdown product of glyphosate) and glufosinate, another herbicide. Neither was detected above the laboratory’s reporting limits.
On its own, this is a snapshot. But placed alongside earlier testing, it begins to take on more context.
Comparing glyphosate results across three rounds of bread testing
Looking at a single round of testing in isolation can only show so much. But when the results are placed alongside earlier batches, a clearer picture begins to emerge.
The first round of testing returned no detectable glyphosate in any of the six bread samples tested. At the time, that was reassuring—but it also reflected the limits of what could be measured.
In the second round, that picture began to shift. Some products still returned non-detect results, while others showed measurable residues.
This third round builds on that, allowing for direct comparison across multiple batches of the same or similar products.
What stands out is not simply that glyphosate can be detected, but that certain products show similar patterns across different test rounds.
For example, Burgen Superb Soy & Linseed returned a detectable result in the second round (0.089 mg/kg) and again in the third round (0.168 mg/kg), both from different batches. Vogel’s Original Mixed Grain shows a similar pattern, with detectable levels in both the second (0.020 mg/kg) and third (0.033 mg/kg) rounds.
At the same time, some products continue to return non-detect results across repeated testing. Tip Top Supersoft and Woolworths wheatmeal-style breads showed no detectable glyphosate in all three rounds of testing.
These comparisons are limited to the products tested and the batches sampled. But taken together, they suggest that differences in results are not simply random across bread types. In some cases, the same products appear to return similar outcomes across repeated testing.
Which raises a practical question: if some products consistently return non-detect results, what is different about how they are produced?
Are glyphosate levels in NZ bread within legal limits?
All of the results recorded in this round of testing fall well below current maximum residue limits (MRLs) for glyphosate in wheat and grain products. From a regulatory standpoint, these products are compliant.
But compliance and absence are not the same thing.
Maximum residue limits are designed to define what is considered acceptable within a risk-based framework. They do not represent zero exposure, and they are not intended to reflect cumulative intake across multiple foods over time.
For many people, the more relevant question is not whether a residue is allowed, but whether it is expected—particularly in staple foods consumed regularly.
Why glyphosate levels may differ between bread products
At this stage, the data points to patterns, but not a single cause.
Several factors could influence the presence or absence of detectable glyphosate residues in bread. These include how the grain is grown, whether glyphosate is used as a pre-harvest desiccant, how grain is sourced and blended, and how it is processed during milling.
For example, more refined white breads rely on flour that has had the outer layers of the grain removed. Those outer layers are also where residues are more likely to be present. Wholegrain and multigrain breads, by contrast, retain more of the original grain structure.
That may explain part of what we are seeing, but not all of it.
What the results suggest is a system with multiple variables—some of which appear to reduce residue levels, and others that allow them to persist.
What this testing shows — and what it doesn’t
This testing reflects specific products, from specific batches, tested under defined laboratory conditions. It does not claim to represent all bread or all production systems.
What it does provide is independent, real-world data drawn directly from products available to New Zealand consumers.
In a space where much of the conversation is shaped by regulatory thresholds and theoretical models, this kind of testing adds something different. It shows what is actually present, at a level that is measurable, and comparable across products.
Why independent glyphosate testing relies on community support
Testing like this is expensive, and we are not funded by industry or government. In this instance, each sample cost $351 plus GST, bringing the total cost of this round of testing to $3,229.20. (Lab costs increased on 01 April 2026)
This work is made possible by a growing community of supporters who value independent testing and transparent reporting. That support allows us to move beyond assumptions and into measurement, building a clearer picture of what is present in everyday foods.
Importantly, all donations go directly toward laboratory testing. They do not fund wages, product purchases, or courier costs—they fund the testing itself.
If you find value in this work and would like to support future testing, you can do so here:
https://nomoreglyphosate.nz/like-what-were-doing/
Whether it’s a one-off contribution or ongoing support, it directly shapes what we’re able to test next.
As this work continues, there are more products to test, more categories to explore, and more patterns to understand.
What these NZ bread test results suggest going forward
This third round of testing does not close the loop, but it does add weight to what is beginning to emerge.
Across repeated testing, some products continue to return no detectable glyphosate, while others return measurable levels. Those patterns do not appear to be evenly distributed.
If all bread were produced under similar conditions, we might expect more consistent results—but that’s not what we’re seeing.
And once that difference becomes visible across multiple rounds of testing, it shifts the conversation—from whether residues can be detected, to why those differences exist in the first place.
Further reading on glyphosate in food and NZ testing
As more testing is completed, a clearer picture begins to emerge. Rather than relying on a single set of results, this work is building a growing dataset of glyphosate levels in everyday foods available in New Zealand.
You can explore all previous testing results here:
- Glyphosate Testing Results — No More Glyphosate NZ
https://nomoreglyphosate.nz/tag/testing-results/
This includes earlier bread testing, where most samples returned non-detect results at the laboratory threshold, as well as more recent testing that begins to show greater variation between products.
Taken together, these results provide a more complete picture than any single test on its own.
Looking ahead — from testing to understanding
At some point, conversations about food shift from assumptions to evidence.
Testing does not answer every question. But it does change the nature of the discussion. Once patterns begin to repeat, they invite a closer look.
Not just at what is happening—but at what could be done differently.
P.S. In previous rounds of testing, we have shared results with food producers and offered them the opportunity to comment. In most cases, no response was received, and where responses were provided, they typically reflected standard corporate communications.
To keep this process practical and sustainable, we are no longer proactively seeking comment prior to publication. However, any producer who wishes to respond to the findings presented here is welcome to do so, and we will include relevant comments as they are received.
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