A recent development in Canada has raised an interesting question for New Zealand.
Not because Canada has suddenly decided glyphosate is unsafe, and not because Canadian regulators have announced a ban or major restriction. Rather, the development raises a broader question about how modern regulators should monitor widely used pesticides.
If Canada believes glyphosate warrants continuous oversight, should New Zealand be doing the same?
Recently, it came to our attention that glyphosate is being monitored under Health Canada’s Continuous Oversight Policy, a framework formally introduced by the Pest Management Regulatory Agency (PMRA) in October 2025.
Importantly, Canadian regulators have stressed that inclusion within the continuous oversight framework does not indicate a new safety concern. Bayer has also stated that the change reflects a broader shift in how pesticides are monitored rather than a specific problem with glyphosate itself.
Yet the announcement raises a wider question about how modern regulatory systems should operate.
Should regulators periodically revisit chemicals every decade or so?
Or should they continuously evaluate new evidence as it emerges?
For New Zealanders, that question may be worth asking.
What Is Canada’s Continuous Oversight Policy?
Historically, many pesticide approvals have relied on formal reassessments conducted at fixed intervals.
A chemical is approved, data is reviewed, and regulators revisit the product years later unless a major issue arises in the meantime.
That model was developed in an era when scientific research moved much more slowly.
Today, new studies are published every week.
Researchers continue to investigate glyphosate’s potential effects on human health, soil biology, biodiversity, endocrine systems, microbiomes, and environmental contamination pathways. Lawsuits continue to generate new evidence and expert testimony. Biomonitoring studies continue to examine human exposure levels in different populations.
The volume of information available today is vastly different from what regulators faced twenty or thirty years ago. Canada’s Continuous Oversight Policy appears to acknowledge this reality.
Rather than relying primarily on fixed review schedules, the goal is to continuously assess emerging information and determine whether regulatory action may be required.
At least in principle, the approach allows regulators to stay closer to the science as it develops.
How Does New Zealand Review Glyphosate and Other Pesticides?
New Zealand’s Environmental Protection Authority (EPA) has mechanisms that allow hazardous substances to be reassessed.
However, reassessments do not occur automatically every few years.
Instead, they are generally triggered when an application for reassessment is submitted and the EPA determines that sufficient grounds exist to proceed.
Glyphosate became the subject of significant public attention in New Zealand when the Environmental Law Initiative (ELI) sought a reassessment of the herbicide. In 2021, the EPA declined the request, concluding that the information presented did not justify opening a formal reassessment process.
That decision was subsequently challenged through the courts, leading to years of legal proceedings before the appeal process ultimately concluded.
Throughout that period, new studies on glyphosate continued to be published around the world, raising an obvious question: if scientific evidence continues to evolve between reassessment requests, who is actively monitoring and evaluating that information?
Why Continuous Monitoring Is Different From Periodic Reassessment
The debate is often framed as a choice between two positions. Either glyphosate is safe. Or glyphosate is dangerous.
But regulatory systems are not actually designed around absolute certainty. They are designed to manage uncertainty.
New analytical methods can reveal exposure pathways that were previously difficult to measure. Long-term environmental effects may also take years or decades to become fully understood. Regulatory systems therefore operate in an environment where uncertainty is constantly being reduced, but rarely eliminated.
In that context, continuous oversight is not necessarily an admission that something is wrong. It may simply be recognition that science never stands still.
Many New Zealanders would likely expect regulators to keep monitoring important chemicals even after approval decisions have been made.
The question is whether existing systems are structured to do that effectively.
Why Continuous Oversight Could Improve Public Confidence
One of the challenges surrounding glyphosate is that public trust has become deeply divided. Some people believe regulators have thoroughly assessed the evidence and reached the correct conclusions. Others believe important risks have been overlooked or dismissed.
The result can be a gap between regulatory decisions and public confidence.
Continuous oversight may offer one way to address that problem.
Rather than waiting for a major controversy, a court case, or a reassessment application, regulators can demonstrate that they are actively monitoring developments as they occur.
Whether that monitoring ultimately changes regulatory conclusions is a separate question. The important point is that the process remains visible and ongoing.
For many members of the public, confidence in the review process may be just as important as the final decision itself.
How Does New Zealand’s Approach Compare With Canada?
It would be premature to conclude that one system is clearly superior to the other.
Canada’s approach is still relatively new, and it remains to be seen how Continuous Oversight will operate in practice.
However, the development does highlight an important difference in regulatory philosophy. One model relies primarily on periodic reassessments triggered by specific events or applications, while the other seeks to continually monitor incoming information and respond when necessary.
Both approaches aim to protect public health and the environment. The question is whether one is better suited to an era where scientific evidence is expanding at an unprecedented rate.
What Would Continuous Glyphosate Monitoring Look Like in New Zealand?
When people hear the phrase “continuous oversight,” it is easy to imagine regulators constantly re-testing products or conducting major reviews every few months. In reality, the concept is usually much more practical than that.
Continuous monitoring does not necessarily mean changing regulatory decisions every time a new study is published. Instead, it means having a structured process for identifying, reviewing, and assessing new information as it emerges.
For glyphosate, that could include monitoring newly published scientific studies, reviewing biomonitoring data that measures human exposure, tracking environmental monitoring programmes and food residue monitoring data, and evaluating regulatory decisions being made overseas. It could also involve assessing new evidence related to health effects, environmental impacts, resistance development, or changing patterns of use.
A system like this might also help identify trends that would otherwise be difficult to spot. One study on its own may not alter a regulator’s conclusions. However, a growing body of evidence pointing in the same direction could warrant closer examination over time.
Continuous oversight could also improve transparency. Rather than waiting for a reassessment application or legal challenge to trigger public discussion, regulators could periodically communicate what new evidence has been reviewed and whether it has changed their understanding of the risks.
Importantly, continuous monitoring does not predetermine the outcome. It may confirm that existing regulatory decisions remain appropriate. Equally, it may identify areas where further investigation is needed.
The key difference is that the conversation becomes ongoing rather than episodic. In a world where new research is published every week, some would argue that regulatory oversight should evolve in the same way.
Should New Zealand Adopt Continuous Glyphosate Monitoring?
The Canadian announcement does not prove that glyphosate is unsafe, nor does it automatically mean New Zealand’s regulatory system is inadequate. What it does do is invite a broader conversation about how modern regulators should operate.
If new scientific evidence continues to emerge year after year, should regulators wait for formal reassessment requests before taking a closer look, or should continuous monitoring become the new standard?
Canada appears to have concluded that ongoing oversight is worth pursuing.
Whether New Zealand follows a similar path remains an open question.
For a chemical as widely used and widely debated as glyphosate, many New Zealanders may reasonably wonder whether continuous oversight is exactly what regulators should be doing.
Further Reading
If you’re interested in how regulators monitor chemicals after approval, assess emerging evidence, and decide when reassessments are necessary, the resources below provide additional context on the systems and processes discussed in this article.
Health Canada – Policy on Continuous Oversight of Pesticides
Published in October 2025, this policy document explains how Health Canada’s Pest Management Regulatory Agency (PMRA) monitors scientific literature, incident reports, water monitoring data, and other emerging information throughout the lifecycle of registered pesticides. The document outlines Canada’s shift from periodic monitoring towards a continuous oversight model designed to identify potential risks earlier and support timely regulatory action when necessary.
EPA New Zealand – About the Chemical Reassessment Programme
The EPA explains how hazardous substances can be reviewed after they have already been approved for use in New Zealand. The page outlines who can apply for a reassessment, how substances are prioritised for review, and the role reassessments play in updating or changing existing approvals when new information becomes available.
Safe According to Whom? What Regulators Mean When They Say a Chemical Is Safe
This No More Glyphosate NZ article explores how regulators determine whether a chemical is considered “safe,” including the role of risk assessment, exposure assumptions, and regulatory judgement. It provides useful background for understanding how different regulators can sometimes reach different conclusions while reviewing similar evidence.
Image Source & Attribution
We created the feature image on this page in Canva.
