27
Mar
Preconception and Prenatal Maternal Exposure to Pesticides Linked to Neonatal Health Risks, Study Finds
(Beyond Pesticides, March 27, 2026) In a study of birth outcomes in Arizona, published in the Journal of Exposure Science & Environmental Epidemiology, researchers find that preconception and prenatal exposure to certain carbamates, organophosphates, and pyrethroids increases the risk of lower Apgar scores, a metric used to assess neonatal health at one minute and ď¬ve minutes after birth. The results reveal that exposure to “several pesticide active ingredients at any point during preconception and/or pregnancy were associated with increased odds of low Apgar scores: the carbamates carbaryl and formetanate hydrochloride; the organophosphates diazinon and tribufos; and the pyrethroid cypermethrin.”
This multi-institutional study, led by the University of Arizona with researchers from Harvard Chan School of Public Health and UCLA Fielding School of Public Health, provides novel insights, as it incorporates pesticide exposure over a 15-year period both before conception and throughout pregnancy.
“To analyze associations of preconception and prenatal exposures to carbamate, organophosphate, and pyrethroid pesticide classes and 25 individual active ingredients with newborn Apgar scores to evaluate the relationship between these exposures and neonatal health,” the authors explain. They continue: “We used pesticide use registry and birth certificate data from 2006 to 2020, linked as part of the Arizona Pregnant Women’s Environmental and Reproductive Outcomes Study (Az-PEARS). Exposures were measured as binary variables and defined as living within 500 m of an agricultural pesticide application during preconception (T0, 90 days before conception) and each trimester (T1–T3).”
Additional positive associations between lower Apgar scores are noted for ethephon, phorate, and beta-cyfluthrin during T0, methomyl during T1, and esfenvalerate and fenpropathrin during T2. This highlights how residential proximity to agricultural pesticide exposure can threaten infant health, even prior to conception.
Study Background
While previous research connects pesticide exposures to adverse health effects, such as in the reproductive, endocrine, nervous, and immune systems of the human body and particularly in children, “[f]ew studies have investigated how ambient preconception and prenatal exposures to pesticide active ingredients affect neonatal health, despite the importance of studying sensitive windows of exposure.” Many studies of infant health include assessing biomarkers from birth cohort studies, which can determine gestational exposures to certain pesticide classes, but have results only within a narrow window of time. (See research here and here.)
In referencing maternal residential proximity to pesticide use with Apgar scores in infants, this shows the connection between pre-birth pesticide exposure and neonatal health. Apgar scores, with the highest value being ten, are calculated for newborns one minute after birth and then again five minutes after birth by evaluating characteristics that include skin color, heart rate, reflexes, muscle tone, and breathing. “Previous studies have demonstrated that this scoring system may have predictive value for short-term brain damage and survivability in preterm infants,” the researchers share. (See studies here, here, and here.) Additional research suggests that Apgar scores less than seven predict neurological disorders and respiratory distress.
Methodology and Results
The state of Arizona is one of only two states, along with California, that have a legislatively mandated public pesticide use registry (PUR) database for tracking of commercial and agricultural applications. “This study used the state of Arizona’s PUR, linked to Arizona birth certiď¬cates, to analyze the association of residential proximity during preconception and pregnancy to carbamate, organophosphate, and pyrethroid pesticide classes and their speciď¬c active ingredients agriculturally applied from 2006 to 2020, with newborn ď¬ve-minute Apgar scores,” the authors state.
To connect the use of agricultural pesticides in areas near where the mothers lived (within 500 m), the PUR records were compared with geocoded birth certiď¬cates, provided by Arizona’s Department of Health Services, along with data from the Arizona Pregnant Women’s Environmental and Reproductive Outcomes Study (Az-PEARS). The total sample size for the study includes 1,141,806 newborns and assesses exposure to a total of 25 active ingredients within the carbamate, organophosphate, and pyrethroid pesticide classes.
The Apgar scores were obtained from birth certiď¬cates. While this included both Apgar scores for one minute and five minutes after birth, the study focuses on Apgar scores taken ď¬ve minutes after birth as they are “stronger predictors of neonatal survival compared to the one-minute score.” The researchers continue, saying: “We examined pesticide exposures occurring at any point during preconception and/or pregnancy (T0–T3) as well as exposures during speciď¬c exposure periods. Each model included pesticide active ingredients with at least ď¬ve newborns exposed either during preconception and/ or in utero and having a low ď¬ve-minute Apgar score (<8).”
As a result, a total of 24,272 newborns had a ď¬ve-minute Apgar score below eight. Prior to conception, 5567 mothers were exposed to a carbamate, 16,344 were exposed to an organophosphate, and 26,059 were exposed to a pyrethroid pesticide based on residential proximity to an agricultural source. “Signiď¬cant associations were found for the carbamates carbaryl and formetanate hydrochloride, the organophosphates diazinon and phorate, and the pyrethroids cyfluthrin, esfenvalerate, and zeta-cypermethrin,” the authors report. This provides evidence that agricultural exposure before and during pregnancy is positively associated with lower Apgar scores and could threaten infant health.
Study Limitations
While this study provides crucial insights into a specific area of science that has not been extensively researched, there are a few drawbacks that the researchers recognize and point out. The methodology does not take exposure to multiple pesticides into account, which is a more accurate representation of how exposure occurs since pesticide mixtures are encountered as opposed to single active ingredients one at a time.
The authors also note: “The limitations of this study include that only carbamates, organophosphates, and pyrethroids applied at rates that allowed for statistical analysis with sufď¬cient power were analyzed; therefore, some pesticide active ingredients within these pesticide classes and other pesticide classes were not addressed. Due to a lack of available data, other sources of pesticide exposures outside of agricultural applications, such as residential use, occupational use, and dietary exposures, were not considered.”
In an interview with 19th News, one of the lead authors on the study, Melissa Furlong, PhD, assistant professor of environmental health sciences at the University of Arizona, adds: “This is just one metric of exposure to these pesticides, but it’s concerning because the general population is still exposed to these ingredients… The research would have implications for household use and for residues on fruits and vegetables.”
Previous Research
While there is limited scientific literature connecting preconception and prenatal pesticide exposure to lower Apgar scores, there is a wide body of science linking pesticide exposures to adverse health outcomes in infants. (See Beyond Pesticides’ Daily News coverage on infants and children, as well as the Pesticide-Induced Diseases: Birth/Fetal Effects resource.)
Cited within the current study, this includes:
- Studies (see here and here) link preconception exposure to organochlorines and pyrethroids to the development of autism spectrum disorder (ASD).
- “[P]reconception exposures to certain carbamates, organophosphates, and pyrethroids are associated with stillbirth, which may be a response to neurological or other damage in the early prenatal period.” (See here.)
- Higher urinary levels of diethyldithiophosphate, a metabolite (breakdown product) of many organophosphate pesticides, can impact Apgar scores taken one minute and ď¬ve minutes after birth. (See studies here and here.)
- Infants born to women with lower acetylcholinesterase (AChE) levels, who live in rural areas of Egypt, have lower Apgar scores taken at one minute and ď¬ve minutes compared to infants born to women with normal AChE levels. (See here.)
- “Several epidemiological studies of prenatal carbamate, organophosphate, and pyrethroid pesticide exposures have found associations with neurological and behavioral outcomes… This includes an association with developmental delays, ASD, and reductions in full-scale Intelligence Quotient (IQ) and verbal comprehension scores.” (See research here, here, here, here, here, here, and here.)
Beyond Pesticides’ Resources
Learn more about the Hazards of Pesticides for Children’s Health and why Children and Pesticides Don’t Mix. Preconception, prenatal, and the first few years of life are critical windows of exposure, known as “windows of vulnerability”, that can lead to life-long adverse health effects. The Pesticide-Induced Diseases Database facilitates access to epidemiologic and laboratory studies based on real-world exposure scenarios that link numerous categories of public health effects to pesticides while the Gateway on Pesticide Hazards and Safe Pest Management provides information on specific pesticide active ingredients, as well as alternatives.
Make The Safer Choice and avoid hazardous home, garden, community, and food use pesticides to protect you and your family. Start by Eating with a Conscience and choosing organic food to protect not only health but the environment. Beyond Pesticides’ offers tips on Buying Organic Products (on a budget!) or you can Grow Your Own Organic Food.
Be part of the organic solution by helping to transition to a pesticide-free world. Support Beyond Pesticides’ mission by becoming a member or giving today!
Call to Action
Beyond Pesticides is inviting organizations, corporations, and institutions to sign-on to the attached statement on the upcoming U.S. Supreme Court case in which Monsanto/Bayer is seeking to overturn over $10 billion in jury verdicts and settlements and stop future litigation on their failure to warn about the potential cancer effects of glyphosate/RoundupTM. If Monsanto/Bayer wins, chemical companies will be able to legally withhold information on their pesticide product hazards.
With weak federal pesticide law, and ongoing deregulation and dismantling of regulatory agencies, accountability in the courts is the last backstop for warning people about pesticide product hazards—creating an important degree of accountability and safety.
For background on the case, please see Monsanto Brief Introduced as U.S. Supreme Court Considers Liability Immunity for Pesticide Manufacturers.
Beyond Pesticides is circulating this joint statement to express a united front against the disregard that chemical companies supporting this case have for human life and a sustainable environment. While there are several amicus briefs being filed by various groups, space to join those briefs is extremely limited due to the permitted word count. As an alternative and to amplify our voice, Beyond Pesticides will distribute this sign-on document to the media.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Source:
Yang, A. et al. (2026) Residential proximity to agricultural pesticide exposures during preconception and pregnancy and associations with Apgar scores in the Az-PEAR study (2006–2020), Journal of Exposure Science & Environmental Epidemiology. Available at: https://www.nature.com/articles/s41370-026-00849-8.
