26
Jul
Another Study Adds to Science Indicating Mothers’ Exposure to Pesticides During Pregnancy Increases Adverse Birth Outcomes
(Beyond Pesticides, July 26, 2023) An exploratory study published in Environment International adds to the many studies demonstrating residential prenatal pesticide exposure can result in adverse birth outcomes. Residential exposure to five active pesticide ingredients (Ais) fluroxypyr-meptyl, glufosinate-ammonium, linuron, vinclozolin, and picoxystrobin has adverse effects on gestational age (GA), birth weight (BW), mortality after birth, child’s sex, premature development, low birth weight (LBW), small for gestational age (SGA), and large for gestational age (LGA). Pesticides’ presence in the body has implications for human health, especially during vulnerable life stages like childhood, puberty, pregnancy, and old age.
Pesticide exposure during pregnancy is of specific concern as health effects for all life stages can be long-lasting. Birth and reproductive complications are increasingly common among individuals exposed to environmental toxicants like pesticides. The Centers for Disease Control and Prevention (CDC) reports birth defects are the leading cause of infant mortality, with one in every 33 infants born with an abnormality that results in death. Therefore, studies like this can help government and health officials safeguard human health by assessing adverse effects following prevalent chemical exposure.
Using a Dutch birth registry from 2009 to 2013, the researchers selected pregnant mothers over 16 years who were living in non-urban areas (who have never moved addresses or only moved once) as participants. Researchers estimated how many kg of the 139 active ingredients are used within 50, 100, 250, and 500 meters of the mother’s home during pregnancy. To determine the association between evidence of reproductive toxicity and gestational age (GA), birth weight (BW), perinatal mortality, child’s sex, prematurity, low birth weight (LBW), small for gestational age (SGA) and large for gestational age (LGA) among select active ingredients, the study employed generalized linear models, adjusting for individual and area-level confounders. The results demonstrate maternal residential exposure to fluroxypyr-meptyl and vinclozolin has associations with longer GA, exposure to glufosinate-ammonium increases the risk of LBW, and linuron exposure has an association with higher BW and higher probabilities of LGA. Additionally, picoxystrobin has associations with a higher likelihood of LGA.
Environmental contaminants like pesticides are ubiquitous in the environment, with 90 percent of Americans having at least one pesticide compound in their body. Numerous studies indicate chemical exposure mainly stems from dietary exposure, like food and drinking water, and researchers caution that there are hundreds to thousands of chemicals that humans are likely to encounter. Just as nutrients are transferable between mother and fetus, so are chemical contaminants. Studies find pesticide compounds in the mother’s blood can transfer to the fetus via the umbilical cord. A 2021 study finds pregnant women already have over 100 detectable chemicals in blood and umbilical cord samples, including banned chemicals. However, 89 percent of these chemical contaminants are from unidentified sources, lack adequate information, or were not previously detectable in humans. Considering the first few weeks of pregnancy are the most vulnerable periods of fetal development, exposure to toxicants can have much more severe implications. A 2020 study finds prenatal pesticide exposure can increase the risk of the rare fetal disorder holoprosencephaly. This disorder prevents the embryonic forebrain from developing into two separate hemispheres. Moreover, women living near agricultural areas experience higher pesticide exposure rates, increasing the risk of birthing a baby with abnormalities. These birth abnormalities can include acute lymphoblastic leukemia and Attention-Deficit/Hyperactivity Disorder (ADHD). Even common household pesticide use during pregnancy can increase nephroblastoma (kidney cancer) and brain tumor risk in children. Therefore, prenatal and early-life exposure to environmental toxicants like pesticides increases susceptibility to disease for both mother and child’s health.
The rates of preterm births, miscarriages/stillbirths, and birth malformations are increasing. Additionally, many current-use pesticides and metabolites (or breakdown products) of many long-banned pesticides still impart negative effects on human health that can continue into childhood and adulthood and may have multigenerational consequences. Thus, pesticide exposure poses a risk to mothers, their subsequent offspring, and future generations. Researchers at Drexel University report that higher levels of some organochlorine compounds, like DDT, during pregnancy are associated with autism spectrum disorder (ASD) and intellectual disability (ID). Although the U.S. bans many organochlorine compounds, the ongoing poisoning and contamination underscore how pervasive and persistent these chemicals are and their continued adverse impact on human health.
This study amplifies the growing body of scientific research evaluating pesticides’ effects on newborns. Exposure to specific pesticides can increase the risk of higher BW, LGA, and longer GA, indicating an association between these neonatal complications and increased risk of obesity and cardiovascular diseases later in life. Although fluroxypyr-meptyl is one of the only pesticides in the study still approved for use in the European Union (EU), imported products can contain contamination from the remaining active ingredients via countries where use is possible. Moreover, some current-use pesticides share similar modes of action with the active ingredients in this study, suggesting future research on the effects of maternal pesticide exposure can use these findings as models. The study concludes, “The underlying mechanism driving these effects are unclear, but the findings warrant more research into the effects of (non-occupational) exposure to these pesticides on human health, especially in the vulnerable population of pregnant women and their babies. [Active ingredients] that were correlated or that share the same modes of action with the identified in this study may also be considered as leads for further research.”
Such ubiquitous exposure to environmental chemicals is of growing concern. But even more concerning are the multiple studies pinpointing the adverse health outcomes that are linked directly to the chemical exposures. With the range of ever-present environmental hazards, advocates argue that it should be incumbent upon regulators to act quickly and embrace a precautionary approach. In the absence of protective regulations from the widespread use of pesticides, U.S. residents, particularly sensitive populations like pregnant mothers, are encouraged to take precautions.
There is a growing consensus that exposure to environmental toxicants before pregnancy can impair fertility, pregnancy, and fetal development. Thus, doctors and pediatricians strongly agree that pregnant mothers should avoid pesticide exposure during critical developmental periods. Exposure concerns about pesticides and other environmental toxicants are increasing significantly, especially for adults and children more vulnerable to their toxic effects. Moreover, many pollutants are subject to regulatory standards that do not fully evaluate exposure-associated disease risks. Advocates say that addressing the manufacturing and use of pesticides is essential to mitigate risks from chemical exposure to toxic pesticides. Therefore, advocates urge that policies strengthen pesticide regulations and increase research on the long-term impacts of pesticide exposure.
Beyond Pesticides tracks the most recent studies related to pesticide exposure through the Pesticide Induced Diseases Database (PIDD). This database supports the clear need for strategic action to shift away from pesticide dependency. For more information on the multiple harms of pesticide exposure, see PIDD pages on Birth/Fetal Effects, Sexual and Reproductive Dysfunction, Body Burdens, and other diseases. To learn more about how inadequate pesticide regulations can adversely affect human and environmental health, see Beyond Pesticides’ Pesticides and You article “Highly Destructive Pesticide Effects Unregulated.”
Human and environmental contamination from pesticides can be reduced through the buying, growing, and supporting organic. Study after study finds that making the switch to an all-organic diet significantly reduces pesticide metabolite levels in urine. Furthermore, given the wide availability of non-pesticidal alternative strategies, families and agroindustry workers can apply these methods to promote a safe and healthy environment, especially among vulnerable population groups. For more information on how organic is the right choice for consumers, see the Beyond Pesticides webpage, Health Benefits of Organic Agriculture.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Source: Environment International
