When people hear the word testing, they often assume it means one thing: precise measurement.
How much is there?
Is it above a legal limit?
Is it “safe” or “unsafe”?
That expectation makes sense — but it doesn’t reflect how environmental testing actually works, or why different types of tests exist in the first place.
As No More Glyphosate NZ begins testing public spaces like playgrounds and parks, it’s important to be clear about what these tests are designed to do — and what they are not.
This is not about lowering the bar.
It’s about asking the right question at the right stage.
Why Environmental Testing Starts With Detection, Not Dose
In many areas of science, the first question isn’t how much — it’s simply:
Is it there at all?
That distinction matters.
Screening tests are widely used in environmental monitoring, food safety, water quality, and public health because they answer a foundational question: presence or absence.
Before you can responsibly debate exposure levels, risk thresholds, or long-term effects, you first need to establish whether a substance is present in the environment being examined.
If it isn’t there, the conversation ends.
If it is, the conversation changes.
Why Detecting Glyphosate Presence Still Matters
It’s sometimes suggested that detecting a substance without immediately quantifying it is meaningless.
In reality, the opposite is true.
Detection establishes:
• that a substance is entering a space where people live, play, or work
• that an exposure pathway exists
• that assumptions about “non-use” or “minimal contact” may not hold
• that further investigation may be justified
Presence doesn’t claim harm.
It doesn’t declare danger.
It signals relevance.
And relevance is what triggers responsible next steps.
What Screening Tests Are — and Why They’re Used
How Screening Tests Differ From Full Quantitative Analysis
Environmental testing is often staged.
Stage 1: Screening
Is the substance detectable at all?
Stage 2: Targeted analysis
Where is it showing up, and under what conditions?
Stage 3: Quantification and assessment
How much is present, how often, and in what context?
Skipping the first stage doesn’t make science stronger — it makes it less efficient and more expensive.
Starting with screening allows:
• limited resources to be used responsibly
• testing to focus on places that actually warrant deeper analysis
• early assumptions to be challenged with real-world data
This is standard practice in many fields, not a deviation from them.
Why This Testing Focuses on Presence, Not Exposure Levels
Dose-based debates tend to dominate public discussions about glyphosate.
But dose alone doesn’t answer every question — especially in public spaces, where exposure is:
• unintentional
• repetitive
• experienced by different age groups
• cumulative over time
In playgrounds, parks, and shared spaces, the first issue isn’t regulatory thresholds — it’s whether residues are present where people reasonably assume they are not.
That’s a different question from agricultural application, and it deserves its own evidence base.
When Detection Leads to Further Investigation — Not Alarm
There’s a common fear that detecting a chemical automatically leads to alarmism.
It doesn’t have to.
Responsible detection does three things:
- Clarifies reality — replacing assumptions with data
- Narrows debate — from abstract arguments to specific locations
- Enables proportional response — rather than blanket claims
Presence doesn’t mean “stop everything.”
It means “let’s look more closely.”
That’s not activism.
That’s diligence.
What Screening Tests Can’t Tell Us on Their Own
To be clear, screening tests do not tell us:
• precise exposure levels
• individual health outcomes
• long-term risk on their own
• causation
Those questions require more detailed analysis — and often institutional involvement.
But without initial detection, those conversations never begin.
Why Clear Testing Language Matters for Public Understanding
Much of the frustration around glyphosate debates comes from people answering different questions.
One side argues safety thresholds.
The other questions environmental presence.
Both think they’re answering the same question — but they aren’t.
By clearly separating presence from amount, we avoid overstating claims and understating concerns at the same time.
That clarity protects credibility — including ours.
The First Question Environmental Testing Needs to Answer
At this stage, the most responsible question isn’t:
“Is it within limits?”
It’s:
“Is it present where people don’t expect it to be?”
Once that’s answered, everything else can follow — carefully, proportionally, and transparently.
That’s how meaningful inquiry starts.
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Image Source & Attribution
We’re grateful to the talented photographers and designers whose work enhances our content. The feature image on this page is by Talha Hassan. You can find more of their work here: https://unsplash.com/@talhahassan116.
