New peer-reviewed research suggests exposure to multiple pesticides significantly increases the risk of pregnancy complications compared to single pesticide exposure. This raises critical questions about pesticide and herbicide safety in food production and agricultural communities.
The study, which bio-monitored pregnant women in an agricultural region of Argentina, adds to growing evidence of heightened dangers from pesticide mixtures. Authors from the National University of the Littoral in Argentina emphasize the need to study pesticide mixtures, as current regulations often focus on single compounds, despite people frequently encountering multiple pesticides in food or farming areas. They highlight the “exposome” concept, stressing the importance of studying pesticides as mixtures.
This research follows a University of Nebraska study linking multiple pesticide exposure to a 36% increased chance of childhood brain cancer.
In the current study, researchers found approximately 40 different pesticides in urine samples from nearly 90 pregnant women in Santa Fe, Argentina. 81% of women had at least one pesticide, 64% had multiple, and 34% experienced pregnancy complications.
While urban women had only slightly fewer pesticides than rural women (suggesting food as a significant exposure route), 70% of rural women showed multiple pesticides compared to 55% of urban women. Rural participants were over twice as likely to have pregnancy-related complications, partly due to more frequent mixture exposure.
Common complications included gestational hypertension and intrauterine growth restriction. Findings also pointed to specific dangers from triazole fungicides, widely used on crops like corn, soybeans, and wheat, which were found at higher levels in women with complications and are suspected reproductive toxicants. Despite a four-fold increase in triazole fungicide use in the US between 2006 and 2016, regulatory scrutiny remains limited.
Nathan Donley, a pesticides researcher not involved in the study, noted that pesticide mixture exposure is “the rule, not the exception,” yet we “have absolutely no clue how different mixtures interact.” He added that minimal US regulatory oversight exists because determining health impacts of mixtures is complex, leading to a default assumption of safety until proven otherwise. Donley advocates for greater precaution given these unknown risks.
