MPI’s decision not to raise glyphosate limits on wheat, barley, and oats might sound reassuring at first glance.
The limits remain at 0.1 mg/kg on those cereals — however for dry field peas, the new limit will now be set at 6 mg/kg (in line with overseas markets). On paper, that still looks like the right outcome.
But there’s a line in MPI’s media release that raises more questions than it answers.
They say they were confident that the originally proposed higher limits “would not have presented any health risks” to consumers. That’s a bold statement — especially when the same announcement acknowledges that glyphosate use patterns in New Zealand have changed significantly over the past 5–6 years.
And this is where real-world evidence matters.
Because while the limits have technically “stayed the same” for cereals, our own community-funded independent laboratory testing has already found glyphosate residues in multiple retail food products at current levels. That isn’t modelling or theoretical exposure — that’s real exposure. That’s what is on supermarket shelves right now.
So when regulators claim that higher limits would have been “safe” anyway — what is that confidence based on? What assumptions sit beneath that statement? And if exposure is already occurring under the status quo, how do we meaningfully evaluate an increase?
This isn’t about alarmism. It’s about transparency — and whether certainty is being asserted… or actually demonstrated.
What Does “No Health Risk” Actually Mean — and Who Decides?
When officials say there is “no health risk”, most people assume that this means one thing:
that the exposure has been measured, evaluated, and proven safe.
But that isn’t how MRLs work.
Maximum Residue Levels are not health-protective limits. They are trade limits — set to reflect what is expected to be present in food under “normal use.” MRLs don’t prove safety. They simply define compliance.
So when MPI uses the phrase “no health risk”, what are they referring to?
Is this based on New Zealand-specific measurement of glyphosate in blood, urine, or breastmilk?
No.
Is it based on monitoring real food products to see how often limits are breached, and whether those breaches correlate with actual exposure?
No.
Is it based on a full toxicological assessment of glyphosate + surfactants + other formulation additives as they exist in Roundup® products — the products people actually use in real life?
No.
The “confidence” in safety largely comes from regulatory assumptions — and those assumptions are built on animal data, short-term studies, and mathematical models. And those models do not include chronic, low-dose, everyday exposure from multiple foods, multiple days in a row, across an entire population.
So when a regulator asserts “no health risk”, that doesn’t mean safety has been proven.
It usually just means the model says it should be fine.
And without active surveillance of what New Zealanders are actually exposed to — how would anyone know if that model holds true?
Because right now, the only real-world data we have — the only actual measurement — is coming from independent testing funded by ordinary people.
And that alone should make us cautious about accepting simple reassurance as evidence.
When Exposure Is Real — Assumptions Stop Being Enough
One of the key differences between MPI’s position and what we are seeing in our own work is that our view isn’t based on projections or modelling — it’s based on measurement.
We’ve already found glyphosate residues in New Zealand retail food under the current limits, and that shifts the discussion entirely. This is no longer theoretical exposure or predicted dietary intake; this is what is actually showing up in everyday products.
And once exposure is real, the question of safety can’t simply rely on confidence statements or assumptions built into regulatory models. It becomes a matter of demonstrating, with evidence, that real-world residues pose no harm over time — especially when those exposures accumulate, involve multiple food types, and occur across an entire population over time.
Without that kind of evidence, “no health risk” starts sounding less like a scientific conclusion and more like a presumption. In a situation where glyphosate is already detectable in food at current settings, the bar for proving safety should logically be higher — not lower.
If Exposure Exists Already — Why Push for Higher Limits?
That’s the part that still doesn’t make sense to many people watching this unfold. If residues are already showing up in retail food at the current settings, then what exactly was driving the proposal to raise them in the first place?
MPI’s media release implies that changes in grower practice were a key factor in stepping back from higher limits — but that suggests the original proposal wasn’t grounded in current use patterns to begin with.
If the sector had already shifted away from pre-harvest glyphosate on human-consumption cereals, then why were higher limits even considered?
And if the public response was one of the reasons MPI changed course, then it raises an uncomfortable possibility: that some regulatory decisions may be driven more by alignment and convenience than by fresh scientific evaluation of real-world exposure in New Zealand.
When exposure is real — and when limits are already being met or exceeded — the idea of raising those limits starts to look more like a paperwork solution than a public health one. It tidies the numbers. It makes breaches disappear.
But it doesn’t answer the real question: how do we know what these residues mean for long-term human health when we’re not actively measuring exposure in the general population, and no one is routinely tracking what New Zealanders are actually consuming day to day?
The Decision Itself Raises Questions — Because the Logic Isn’t Straightforward
What still hasn’t been explained is why MPI chose to completely abandon the increases for wheat, barley, and oats — instead of simply reducing the scale of the increase. If the original proposal was 10 mg/kg, and MPI were truly confident those levels posed “no health risk,” then why not settle on something in between — say 3 or 5 mg/kg — as a compromise? We don’t have an answer for that. The leap from “10 mg/kg is safe” to “0.1 mg/kg is the right limit after all” doesn’t have a clear explanation in the public record.
And then there is the outlier: peas.
Only peas received the higher limit — lifted to 6 mg/kg — despite peas not being a major domestic staple or, from what we can tell, a major export driver. That decision is hard to reconcile if the stated reasoning is health risk.
If the logic is “alignment with overseas markets,” that may explain the number — but it doesn’t explain why public health reasoning applied to cereals apparently doesn’t apply to peas.
The difference feels arbitrary — or at least unexamined — and that gap in reasoning matters, because it makes it harder for the public to understand what principle is actually guiding New Zealand’s regulatory stance.
Was this driven by science? By trade? By industry comfort? Or simply by political risk?
We genuinely don’t know — and MPI hasn’t clearly said.
Do Limits Protect the Public — or Do They Protect the System?
This is really the heart of the issue. Maximum Residue Levels are often presented to the public as if they are health-protective thresholds, set at the point where risk becomes unacceptable.
In reality, MRLs are not designed that way. They are set around expected residues under “normal agricultural use,” and adjusted when practices shift, markets change, or compliance becomes difficult to maintain.
When viewed through that lens, it becomes easier to see why an increase might have been proposed in the first place — not because consumers were at risk at 0.1 mg/kg, but because industry expected higher levels to show up. In other words, MRLs tend to follow the way chemicals are used, not lead it.
And when residues do exceed the limit — as has already happened in New Zealand — the consequences have been minimal. No recalls. No penalties. No public warnings. We’ve seen this pattern before — warnings ignored, findings shelved, and opportunities to fix the system quietly passed over.
When a limit can be breached without regulatory action, it’s hard to argue the limit exists primarily to protect consumers. It begins to look more like a number designed to define “allowed” versus “not ideal,” rather than safe versus unsafe.
Which raises the uncomfortable possibility that MRLs are functioning as compliance management tools — instruments for system stability — rather than the firm health-protective lines many people assume them to be.
Where Transparency Matters Most — Evidence, Not Assumptions
All of this brings us to a very simple expectation — and it shouldn’t be controversial: when a regulator claims something is safe, the public deserves to see the basis for that claim. Not the shorthand. Not the headline. The evidence.
At the moment we have reassurance, confident wording, and references to international alignment — but we don’t have the underlying analysis that demonstrates what real exposure means for New Zealanders in 2025.
Meanwhile, independent testing — the only real-world measurement happening in this country right now — is showing that glyphosate residues are already present in everyday supermarket food. That is a gap that cannot be ignored.
If exposure is measurable, then safety needs to be measurable too. If residues are entering the food supply, then the health implications of those residues must be evaluated — not assumed away. And if regulators are going to claim certainty, then that certainty has to be earned.
Because at this point, the only data we have isn’t coming from the system itself — it’s coming from the people who decided to test what the system doesn’t measure.
And with the latest news that the glyphosate reassessment is being pushed even further out in New Zealand, the gap between exposure data and regulatory action only widens.
The Gap Between Assurance and Evidence
We are left with a decision that appears positive on paper, but still lacks a clear explanation underneath. MPI did not raise limits for the cereals most New Zealanders consume daily, yet they assert those higher limits would have posed no health risk.
They then increased the limit for peas — a smaller crop — without fully explaining the reasoning behind treating that category differently. And all of this sits against a backdrop where no one in government is routinely measuring glyphosate exposure in the population, while independent testing is already showing residues at current settings.
If confidence is being expressed without transparent evidence, then the public is only being asked to trust — not to understand. And trust is not what it used to be in this country. Over recent years we’ve seen a steady erosion of faith in government agencies, in regulators, and even in the political process itself — because too often the reasoning behind big decisions hasn’t been openly shared.
In that context, clarity is not optional. Openness is not a nice-to-have. If the system wants to rebuild trust, then transparent evidence must sit at the centre of the conversation — not assumptions, and not reassurances.
Resources & References
Before forming an opinion on what’s “safe” or “acceptable,” it helps to explore the evidence that underpins — or challenges — the assumptions regulators work from.
MPI media release — Glyphosate residue limits to stay at 0.1mg/kg (2025)
New Zealand Food Safety confirms it will keep wheat, barley, and oats at 0.1 mg/kg, while setting peas at 6 mg/kg — despite asserting that higher limits would not have posed health risks.
No More Glyphosate NZ — Honey testing results
Independent community-funded testing of retail honey found glyphosate above NZ’s legal limit, highlighting real exposure at current settings.
No More Glyphosate NZ — Weet-Bix testing results
Accredited lab testing identified glyphosate residues in one of New Zealand’s most widely consumed cereals — demonstrating exposure through household staples.
No More Glyphosate NZ — Bread testing in progress
Early bread testing (with more underway) is already showing residues at current limits — reinforcing the need for exposure measurement, not assumptions.
MRLs in New Zealand — A regulatory explainer
How Maximum Residue Levels are set, why they follow expected agricultural use — and why they do not equal proven safety.
The science will continue to evolve, but one principle should guide us now: when residues are already showing up in food, reassurance is not enough — exposure must be measured, understood, and taken seriously.
Image Source & Attribution
The feature image on this page is a screenshot of the Ministry for Primary Industries (MPI) website page: Glyphosate residue limits to stay at 0.1mg/kg for wheat, barley and oats, with restrictions introduced on permitted use edited using Canva.com
