We’ve written about endocrine disruption, hormonal imbalance, and the potential reproductive risks of glyphosate before
…but until now, we haven’t written about male fertility.
It’s a topic that rarely makes headlines. But a new animal study — published in a respected pharmacology journal in November 2025 — adds weight to a growing concern:
Glyphosate-based weedkillers like Roundup may be quietly damaging sperm and testicular function in ways that aren’t being discussed — or regulated.
And that raises serious questions for Kiwi men, for families trying to conceive, and for anyone wondering what long-term exposure might mean for future generations.
New Study Links Glyphosate to Sperm Damage
Let’s start with the science.
In a peer-reviewed study published in Naunyn-Schmiedeberg’s Archives of Pharmacology, researchers exposed adult male mice to a glyphosate-based herbicide at a dose that mimicked real-world exposure — 500 mg/kg daily for 35 days.
The results were alarming.
- Testicular damage: Mice exposed to glyphosate showed significantly reduced testis weight and disrupted tissue structure.
- Sperm dysfunction: Sperm concentration, motility, viability, and normal morphology all declined.
- Hormonal shifts: Testosterone levels dropped. Luteinizing hormone (LH) spiked.
- Oxidative stress increased: The antioxidant system was overwhelmed.
- Inflammation markers rose: Suggesting an immune-related cascade was triggered.
In plain English?
The male reproductive system — from hormone levels to sperm production — was hit hard.
What’s especially revealing is this:
When the mice were also given Coenzyme Q10 — a naturally occurring antioxidant — many of those effects were reduced. Sperm quality improved. Hormone levels began to normalise. Testicular tissue partially recovered.
This wasn’t random damage.
It followed a predictable biological pattern — one driven by cellular stress and inflammation.
And if that’s true in mice, we have to ask:
Could the same mechanism be quietly affecting human fertility, too?
Read the study abstract on PubMed.
Animal studies aren’t perfect mirrors of human biology — but they’re often early warning signals.
If you’ve ever wondered whether rat/mice studies really matter for people, we explored that question in more depth here:
We’re Not Rats… But Maybe We Should Pay Attention Anyway
Glyphosate Detected in Human Semen
If that study stood alone, it might be easy to dismiss. But it doesn’t.
A 2024 report out of France sent a similar chill through the scientific community — this time in humans.
Researchers analyzed semen samples from men attending a fertility clinic. The findings?
- Glyphosate was detected in 57% of semen samples.
- Glyphosate levels in semen were four times higher than in the blood of the same individuals.
- Glyphosate presence was associated with markers of oxidative stress, which can damage sperm and DNA.
This was not a fringe study. It was published by a reputable academic group and widely reported — though barely mentioned in New Zealand media.
So now we have animal data and human data suggesting the same thing:
Glyphosate-based herbicides may be undermining male fertility by increasing oxidative stress and disrupting reproductive function.
What This Means for Male Fertility in New Zealand
We are a country that relies heavily on glyphosate — in agriculture, on roadsides, in home gardens, on sports fields, and even around schools.
It’s detected in our honey, our cereals, our bread.
Historically, it’s been allowed on many of our food crops right up until harvest— and residues are tolerated at levels that some scientists believe are far too high.
Now imagine what that cumulative exposure could mean:
- For a teenager working on a dairy farm.
- For a new dad who just sprayed the driveway or lawn edges with Roundup.
- For a couple struggling to conceive.
- For an unborn child inheriting more than just DNA.
Shouldn’t we be asking if this chemical — already flagged as a probable carcinogen — is also interfering with our ability to reproduce?
Because right now, no regulator in New Zealand is seriously asking that question.
Regulatory Gaps and Reproductive Health Risks
In New Zealand, glyphosate remains one of the most widely used herbicides. Regulators have repeatedly assured the public it is safe when used as directed.
But what those assurances don’t account for are:
- Chronic, low-dose exposure
- Combination effects from commercial formulations
- Sensitive populations like children and reproductive-age adults
- Emerging science on endocrine disruption and oxidative damage
Nor do they reflect the fact that no long-term studies on glyphosate’s reproductive effects have ever been required as a condition of approval.
And while acceptable daily intake levels (ADIs) may be based on “no observed adverse effect” thresholds in rodents, studies like the one above suggest we may already be well past that line — especially when real-world exposure includes more than just pure glyphosate.
How Kiwi Men Can Reduce Exposure
Here’s the hard truth: If you’re exposed to glyphosate regularly — through diet, work, or environment — there may be real consequences that no label is warning you about.
But there are steps you can take:
- Cut dietary exposure by choosing organic or glyphosate-free foods whenever possible
→ See our testing results for NZ honey, Weet-Bix, cereals, and bread - Avoid glyphosate-based weedkillers at home
→ Try our roundup-free garden alternatives here - Support your body’s detox systems with antioxidant-rich foods, zinc, CoQ10, and a healthy lifestyle
- Share this information with your mates, your doctor, your local school
- Join our campaign to demand better testing, better regulation, and better protection for future generations.
Why Male Fertility Deserves More Attention
Sperm counts are falling globally. Male fertility rates are quietly declining. Endocrine disruptors are showing up everywhere — including in our food.
Now, with science pointing to a clear link between glyphosate exposure and male reproductive damage, the question we need to ask is simple:
Why aren’t we doing more to protect our men — and our future families — from this chemical?
Because the evidence isn’t just hypothetical anymore.
And the consequences could last generations.
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Disclaimer:
This article discusses emerging research related to reproductive health and the potential mitigating role of Coenzyme Q10. It is not intended as medical advice. Always consult your healthcare provider before beginning any new supplement, especially if you are pregnant, planning to conceive, or managing a health condition.
Resources & References
Before You Scroll On…
The conversation around glyphosate and male fertility is still unfolding — and often ignored. But the science is already speaking. Below you’ll find studies, expert reviews, and original reporting that informed this article. Together, they raise serious questions about what’s really at stake.
Glyphosate and Hormone Disruption: What We Know So Far
(No More Glyphosate NZ, May 8, 2025)
A site‑feature article exploring the broader evidence that glyphosate and glyphosate‑based herbicides may act as endocrine disruptors, affecting hormone signalling, reproductive health, and intergenerational risk.
Why Raising MRLs Threatens Public Health
(No More Glyphosate NZ, May 8, 2025)
Discussion of how increasing maximum residue levels (MRLs) for glyphosate in foods could undermine public health safeguards—especially for vulnerable populations and reproductive endpoints.
The Death by a Thousand Cuts of Chemical Exposure
(criticalmindshift.com)
A broader‑theme piece on how low‑dose, cumulative exposure to multiple chemicals—including herbicides like glyphosate—can contribute to gradual health declines including fertility.
No Control Group Left: What Happens When Everyone is Exposed
(criticalmindshift.com)
Investigative article about how ubiquitous chemical exposure (including glyphosate) complicates epidemiology and weakens regulatory reliance on “unexposed” control groups when assessing reproductive and endocrine harms.
Coenzyme Q10 protects against glyphosate‑based herbicide‑induced testicular and sperm toxicity by modulating Nrf2/Keap1/HO‑1 and TLR4/NF‑κB pathways
(Mutluay et al., 2025)
A controlled animal study in adult male mice showing that exposure to a glyphosate‑based herbicide (500 mg/kg/day for 35 days) caused testicular damage, declines in sperm concentration/motility/morphology, hormonal shifts (↓ testosterone, ↑ LH), oxidative stress and inflammation. Coenzyme Q10 co‑treatment ameliorated many of these effects.
Glyphosate presence in human sperm: First report and positive correlation with oxidative stress in an infertile French population
(Vasseur et al., 2024)
The first study to report glyphosate detection in human seminal plasma (57% of samples), observed levels four times higher than blood, and a positive correlation with oxidative stress biomarkers—raising concern about male reproductive health.
Review: Mechanisms of Glyphosate and Glyphosate-Based Herbicides Action in Female and Male Fertility in Humans and Animal Models
Serra et al., 2021)
A comprehensive review of animal and in vitro studies showing how glyphosate/GBHs can disrupt the HPG axis (in males and females), alter steroidogenesis, impair gonadal cells, and produce transgenerational effects.
Effects of Roundup and its main component, glyphosate, upon mammalian sperm function and survival
(Nerozzi et al., 2020)
A study in pig‑model semen showing that both glyphosate and its commercial formulation (Roundup) reduced sperm motility and viability in vitro; Roundup was more toxic than glyphosate alone.
We’re Not Rats… But Maybe We Should Pay Attention Anyway
(No More Glyphosate NZ, June 26 2025)
A commentary article exploring how rat studies of glyphosate should not be dismissed when assessing human health relevance, especially in reproductive and endocrine end‑points.
Where This Leaves Us
When reproductive health is at risk, the burden of proof shouldn’t fall on the harmed — it should fall on those making, selling, and approving the chemicals. These references offer a place to start asking better questions. The rest is up to us.
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