Prenatal Cannabis Modified the Effects of Insecticide Exposure on Child Behavior
Among 197 mother-child pairs, prenatal insecticide exposure (not cannabis itself) was associated with altered child behavior, but cannabis exposure modified the effects of the insecticide-tobacco mixture in sex-specific ways.
Quick Facts
What This Study Found
Prenatal insecticides (pyrethroids and organophosphates) were the primary exposures associated with child neurobehavior. Pyrethroid exposure (3PBA) was positively associated with internalizing behaviors (beta=18.1%). Cannabis (THCCOOH) modified the cumulative effect of the tobacco-insecticide mixture: among females with detectable cannabis exposure, the mixture was associated with lower externalizing behaviors (beta=-46.8%, 95% CI: -70.4%, -4.1%).
Key Numbers
197 mother-child pairs. Pyrethroid (3PBA) and internalizing: beta=18.1% (95% CI: 0.0%, 39.5%). TCPY and externalizing: beta=-12.9% (95% CI: -27.8%, 5.0%). Females with detectable THCCOOH, mixture and externalizing: beta=-46.8% (95% CI: -70.4%, -4.1%). Effects were modified by both THCCOOH and sex.
How They Did This
Prospective cohort of 197 mother-child pairs from Atlanta, Georgia. Cannabis, tobacco, pyrethroid, and organophosphate metabolites measured in maternal urine at 8-14 and 24-30 weeks' gestation. Infant arousal and attention assessed at 2 weeks; child behavior assessed annually at ages 2-5 using CBCL. Quantile g-computation and Bayesian kernel machine regression analyzed mixture effects.
Why This Research Matters
Cannabis and tobacco crops are commonly contaminated with insecticides. This study is one of the first to examine how these co-exposures interact during pregnancy, revealing that cannabis may modify the neurodevelopmental effects of pesticides in sex-specific ways.
The Bigger Picture
Most prenatal cannabis research focuses on THC alone, ignoring the contaminants present in cannabis products. This study suggests that the real-world picture is more complex: the insecticides on cannabis and tobacco plants may be contributing to (or modifying) the neurodevelopmental effects attributed to the substances themselves.
What This Study Doesn't Tell Us
Small sample size (N=197) limits statistical power. Urine metabolites capture only recent exposure, not cumulative prenatal burden. Observational design with multiple comparisons raises risk of chance findings. Effect modification by sex and cannabis needs replication. Atlanta-specific cohort may not generalize.
Questions This Raises
- ?Whether pesticide contamination of cannabis products contributes to adverse prenatal outcomes typically attributed to cannabis itself
- ?How prenatal co-exposure patterns differ between states with regulated versus unregulated cannabis markets
Trust & Context
- Key Stat:
- Evidence Grade:
- Prospective cohort with biomarker-confirmed exposures and sophisticated mixture analysis, but small sample and multiple comparisons limit confidence.
- Study Age:
- Published 2025.
- Original Title:
- Associations of prenatal tobacco and insecticide co-exposures with neurobehavioral responses among children born to pregnant women exposed to cannabis.
- Published In:
- Neurotoxicology and teratology, 111, 107536 (2025)
- Authors:
- Sehgal, Neha, Brennan, Patricia A(3), Dunlop, Anne L(3), Liang, Donghai, Corwin, Elizabeth J, Tan, Youran, Everson, Todd M, Caudle, W Michael, Panuwet, Parinya, D'Souza, Priya E, Yakimavets, Volha, Lee, Grace E, Barr, Dana Boyd, Eick, Stephanie M
- Database ID:
- RTHC-07613
Evidence Hierarchy
Watches what happens naturally without intervening.
What do these levels mean? →Frequently Asked Questions
Was cannabis harmful to the babies?
Interestingly, cannabis metabolites alone were not significantly associated with child neurobehavior in this study. Instead, cannabis modified how insecticide and tobacco exposures affected behavior, suggesting complex interactions rather than simple harm from any single exposure.
Are insecticides on cannabis a known problem?
Yes. Cannabis crops can be treated with pesticides, and in states without testing requirements, residues may be present in consumer products. This study adds a new dimension by suggesting these contaminants may affect fetal development in ways that interact with THC exposure.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-07613APA
Sehgal, Neha; Brennan, Patricia A; Dunlop, Anne L; Liang, Donghai; Corwin, Elizabeth J; Tan, Youran; Everson, Todd M; Caudle, W Michael; Panuwet, Parinya; D'Souza, Priya E; Yakimavets, Volha; Lee, Grace E; Barr, Dana Boyd; Eick, Stephanie M. (2025). Associations of prenatal tobacco and insecticide co-exposures with neurobehavioral responses among children born to pregnant women exposed to cannabis.. Neurotoxicology and teratology, 111, 107536. https://doi.org/10.1016/j.ntt.2025.107536
MLA
Sehgal, Neha, et al. "Associations of prenatal tobacco and insecticide co-exposures with neurobehavioral responses among children born to pregnant women exposed to cannabis.." Neurotoxicology and teratology, 2025. https://doi.org/10.1016/j.ntt.2025.107536
RethinkTHC
RethinkTHC Research Database. "Associations of prenatal tobacco and insecticide co-exposure..." RTHC-07613. Retrieved from https://rethinkthc.com/research/sehgal-2025-associations-of-prenatal-tobacco
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.