Autism now affects 1 in 31 children in the United States, with similar rises seen worldwide.
Politicians, scientists, and parents are all searching for answers — and the recent announcement from President Trump and Health Secretary Robert F. Kennedy Jr. put the issue firmly back into the spotlight.
But here’s the trap: every time autism makes headlines, the debate narrows to a single culprit. One year it’s vaccines. Now it’s acetaminophen. Next time it could be something else. What if we’re asking the wrong kind of question?
What if there isn’t just one smoking gun, but many?
Each exposure — glyphosate in food, acetaminophen during pregnancy, endocrine disruptors in plastics, heavy metals in water, multiple vaccines at once — could act like another wedge, prying open the door to immune and nervous system breakdown. Add in generational vulnerabilities carried in our genes, and what looks like a lottery begins to make sense. The odds aren’t random at all — they tilt with every added exposure.
So maybe the rise in autism isn’t about one chemical or one intervention. Maybe it’s about the stacking effect of them all. And if that’s true, then the real question becomes: how many “safe” exposures does it take before the system can no longer cope?
Acetaminophen and Autism
The Trump administration’s first move was bold: ordering the FDA to issue a physician notice and change the safety label for acetaminophen — better known as Tylenol or paracetamol. The reason? A growing body of studies suggesting that when taken during pregnancy, acetaminophen may increase the risk of neurodevelopmental disorders, including ADHD and autism.
It’s a startling shift, considering acetaminophen has long been marketed as one of the safest painkillers around. More than half of pregnant women worldwide take it. Yet systematic reviews, including one led by Harvard researchers, have consistently flagged associations between prenatal acetaminophen exposure and autism or ADHD in children. In many of these studies, the higher the exposure, the higher the risk.
Critics — including the American College of Obstetricians and Gynecologists — caution that the evidence isn’t ironclad. They warn that pregnant women might forgo pain relief unnecessarily, potentially leading to other health risks. And they’re right about one thing: the science isn’t settled.
But here’s where the debate gets stuck: too often it flips between “safe” and “unsafe,” when reality is far messier. What if acetaminophen isn’t the sole culprit but just one of many stressors? On its own, it might not explain a five-fold increase in autism. But combined with other exposures, could it be one more wedge in the door?
Folate and Leucovorin
The second initiative announced was the FDA’s approval of leucovorin — also known as folinic acid — to treat cerebral folate deficiency (CFD), a condition that has been linked to developmental delays and autistic features. Early trials suggest leucovorin may even improve speech in some children, offering a glimmer of hope for families searching for options beyond behavioral therapies.
On the surface, this seems like progress. But it also raises bigger questions. If folate pathways can influence autism symptoms, does that mean genetics alone are to blame? Or could folate disruption be another example of how environment and biology collide?
Consider this: several studies have found that children with autism often carry folate receptor antibodies, which block folate from entering the brain. Without enough folate, the nervous system struggles to develop properly. But what if those antibodies — or the folate pathways themselves — are being disrupted by environmental exposures? Some researchers have even speculated that certain drugs, including acetaminophen, might play a role in that disruption.
In other words, folate metabolism may not be a separate story at all. It might be another piece of the same puzzle — one more wedge that weakens resilience in vulnerable children.
Vaccines in the Spotlight
The third announcement was the one that grabbed the most headlines: Robert F. Kennedy Jr. promised that vaccines will be closely examined as part of the autism inquiry. He noted that up to 70% of mothers who have children with autism believe vaccines played a role, and President Trump went further, saying it’s time to stop gaslighting parents and start listening to them.
For families who have long felt dismissed, this acknowledgement matters. But it also reopens one of the most polarising debates in modern medicine. The mainstream scientific consensus is that vaccines are safe and effective, yet countless parents tell stories of their child changing almost overnight after a round of shots. How do we reconcile official reassurance with lived experience?
What if vaccines, like acetaminophen, are not the smoking gun but a smoking gun? Injecting a newborn or infant with multiple substances — adjuvants, preservatives, and antigens — might be a manageable stress for some children, but not for all. Genetics, timing, and cumulative exposures could tip the balance. For a child already vulnerable due to in-utero chemical exposures, vaccine injury might be the final straw.
It doesn’t have to be either/or. The vaccine question may be one factor in a much larger picture of environmental stressors. The tragedy is that by fighting over absolutes — vaccines always safe, or vaccines always harmful — we may be missing the chance to ask better questions about how all these exposures interact.
More Than One Smoking Gun
When we zoom out, a pattern starts to emerge. Autism has too often been treated like a whodunnit with only one suspect in the lineup. First it was genetics. Then vaccines. Now acetaminophen. Each time, the debate narrows, the camps dig in, and the bigger picture fades.
But what if autism isn’t about a single villain? What if it’s about how multiple exposures collide? Glyphosate in our food, acetaminophen during pregnancy, endocrine disruptors in plastics, PFAS in drinking water, heavy metals in soil and air, vaccine adjuvants in infants — none of these may explain a five-fold increase in autism on their own. But layered together, across generations, they might.
Think of it like a door slowly being pried open. Each exposure is another wedge: small on its own, but cumulative in effect. The more wedges you add, the wider the door opens — until the nervous system and immune system can no longer hold back the pressure. Genetics and family health history set the frame of the door, but it’s daily life in a chemically saturated world that forces it open.
On the surface, it looks like a lottery. One child develops autism, another doesn’t. But maybe it’s not chance at all. Maybe it’s the tally of exposures — visible and invisible — that pushes some children past the tipping point.
Why This Matters for New Zealand
It would be easy to look at Trump and RFK Jr.’s announcements and think: that’s America’s debate, not ours. But the truth is, every piece of this puzzle applies here in New Zealand too.
Acetaminophen (paracetamol) is just as widely used here as in the U.S., especially during pregnancy. Glyphosate is sprayed across our farms, orchards, and even along school grounds. Endocrine-disrupting chemicals are in our plastics and packaging. Vaccines are delivered on a strict childhood schedule, often in multiple doses at once. Add in PFAS, heavy metals, and the many chemicals regulators tell us are present only at “safe” levels — and the question practically asks itself: safe for whom, and safe in what combination?
New Zealand has not yet launched the kind of large-scale biomonitoring or autism–environment studies that could give us real answers. Instead, we rely heavily on overseas data — while assuming our exposures are somehow different. But the reality is, our children are growing up in the same global chemical soup.
If autism is the canary in the coal mine, then the silence here isn’t safety. It’s neglect. Unless we start asking better questions and demanding independent research of our own, we risk repeating the same mistakes — waiting decades to connect the dots while another generation of families pay the price.
Beyond One Smoking Gun
Autism’s rise is undeniable. What remains uncertain — and hotly contested — is why. The danger is that we keep looking for a single cause when the truth may be more uncomfortable: there isn’t just one.
Acetaminophen during pregnancy, folate metabolism disruptions, glyphosate in our food, vaccine adjuvants, plastics, PFAS, heavy metals — each one on its own may not explain a five-fold increase in autism. But together, they form a toxic stack. Layer upon layer, generation after generation, the burden grows heavier until something gives way.
What if autism isn’t a mystery illness so much as a mirror reflecting back the choices we’ve made as a society — the chemicals we’ve normalised, the trade-offs we’ve accepted, the reassurances we’ve clung to?
The announcements from Trump and RFK Jr. may mark a turning point. But the real test isn’t whether America debates acetaminophen or vaccines. It’s whether we — in New Zealand and beyond — are willing to confront the harder truth: that the causes of autism are likely multiple, cumulative, and deeply entangled with how we live.
And that means prevention won’t come from swapping one drug or one exposure for another. It will come from asking a harder question: how much chemical intrusion into human biology are we willing to tolerate before we admit the system itself is breaking down?
Further Reading
The studies and reports below are only a starting point. They show how evidence is building across multiple fronts — from pregnancy medications to pesticides — yet no single factor explains autism’s rise on its own. It’s the overlaps that may matter most.
Evaluation of the evidence on acetaminophen use and neurodevelopmental disorders.
Prada, D., Ritz, B., Bauer, A. Z., & Baccarelli, A. (2025)
Environmental Health, 24(56)
Harvard-led review finding consistent associations between prenatal acetaminophen use and higher rates of ADHD and autism.
Association of cord plasma biomarkers of in utero acetaminophen exposure with risk of ADHD and autism spectrum disorder in childhood. Boston Birth Cohort.
JAMA Psychiatry (2019).
Cord blood biomarkers showed dose-dependent risk increases for ADHD and autism.
Glyphosate exposure in pregnancy and shortened gestational length: a prospective Indiana birth cohort study.
Parvez, S., Gerona, R., Proctor, C., et al. (2018).
Environmental Health, 17(1).
Detected glyphosate in 93% of pregnant women; higher levels correlated with shorter pregnancies.
Exposure to glyphosate-based herbicides and risk for non-Hodgkin lymphoma: A meta-analysis and supporting evidence.
Zhang, L., Rana, I., Shaffer, R., Taioli, E., Sheppard, L. (2019).
Mutation Research/Reviews, 781.
Meta-analysis highlighting cancer risks, relevant to the broader pattern of low-level chemical exposures.
IARC (2015). Glyphosate Monograph.
International Agency for Research on Cancer.
Classified glyphosate as “probably carcinogenic to humans” based on animal and human evidence.
Food Residues Survey Programme Report 2023–2024.
New Zealand Food Safety (2025).
Technical Paper No: 2025/05.
Official pesticide residue monitoring shows breaches and “safe levels” in common foods, raising questions about cumulative exposure.
The Death by a Thousand Cuts of Chemical Exposure
Explores how chronic, low-level chemical exposures — each considered “safe” on its own — can combine over time to create serious health risks.
Taken alone, each of these studies can be debated. Taken together, they suggest a bigger story: autism may not have one cause but many — a layered reality hidden behind the illusion of “safe” exposure. That’s the space Critical Mindshift was built to explore.
Image Acknowledgement
We’re grateful to the talented photographers and designers on Unsplash for providing beautiful, free-to-use images. The image on this page is by Arturo Esparza. Check out their work here: https://unsplash.com/@arturoeg_foto.
