Could a parent’s job influence how autism unfolds in their child? A new UC Davis Health study suggests the answer might be yes, finding that parental workplace exposure to certain chemicals during pregnancy could be linked not only to autism diagnosis but also to its severity, cognitive function, and behavior.
Published in the International Journal of Hygiene and Environmental Health, the research draws on more than 500 families from the long-running CHARGE (Childhood Autism Risks from Genes and Environment) study in California, evaluating chemical exposure from three months before pregnancy through birth.
Linking Jobs to Autism Characteristics
Researchers from UC Davis and the National Institute for Occupational Safety and Health examined both mothers’ and fathers’ job histories, estimating exposure to 16 chemical agents, from plastics and car fluids to disinfectants and pharmaceuticals. They then matched these data with children’s Autism Diagnostic Observation Schedule (ADOS-2) severity scores and assessments of cognitive, adaptive, and behavioral skills.
- Plastics and polymers (such as polyethylene and PVC) were associated with poorer cognitive performance, reduced adaptive skills, and behavioral issues including hyperactivity and social withdrawal.
- Ethylene oxide, used in sterilization, was linked to higher autism severity and weaker daily living skills.
- Phenol exposure correlated with greater autism severity and behaviors like repetitive movements and hyperactivity.
“This research shows that workplace safety isn’t just about protecting the worker — it’s also about protecting their future children,” said co-author Irva Hertz-Picciotto of the UC Davis MIND Institute.
Fathers in the Spotlight
One striking finding was the impact of paternal exposures. The strongest cognitive deficits appeared in children whose fathers were exposed to plastics and polymers, with notable declines in language, fine motor skills, and visual perception. While maternal exposures also showed associations, paternal workplace hazards were more often linked to lower skills and higher autism severity scores.
How Chemicals Might Influence Development
Many of the identified agents are known neurotoxicants. Plastics and their additives can cross the placenta, disrupt hormones, trigger inflammation, and alter gene expression during critical brain development periods. Ethylene oxide and phenol are potential endocrine disruptors and may provoke immune responses that influence neurodevelopment.
Limitations and Next Steps
The authors caution that the study does not prove causation and that exposure estimates relied on job descriptions rather than direct measurements. Some exposures were rare, limiting statistical power. However, the patterns — especially for plastics/polymers and ethylene oxide — were consistent across multiple domains of functioning.
Workplace Safety and Family Health
Given the findings, researchers suggest that occupational health guidelines should consider not just the worker’s well-being but also the potential effects on future children. They call for more studies that include fathers in reproductive health research and for workplaces to adopt protective measures such as improved ventilation and personal protective equipment.
Journal: International Journal of Hygiene and Environmental Health
ScienceBlog.com has no paywalls, no sponsored content, and no agenda beyond getting the science right. Every story here is written to inform, not to impress an advertiser or push a point of view.
Good science journalism takes time — reading the papers, checking the claims, finding researchers who can put findings in context. We do that work because we think it matters.
If you find this site useful, consider supporting it with a donation. Even a few dollars a month helps keep the coverage independent and free for everyone.