Measurement of Agricultural and Dietary Glyphosate Exposure among Pregnant Women

Project Summary/Abstract This request for supplemental funding supports a previously awarded career development grant for Dr. Cynthia Curl. Dr. Curl?s original project aims to understand sources of glyphosate exposure among pregnant women living in agricultural communities. Specifically, she aims to measure long-term glyphosate exposure among a cohort of pregnant women from the beginning of their first trimesters through delivery via a series of repeated weekly first morning void urine samples. In partnership with Women, Infants and Children (WIC) clinics, Dr. Curl is currently recruiting 40 pregnant women in Idaho (as of April 14, 2021, 28 participants have been enrolled, and recruitment will continue until mid-May 2021). These women live in heavily agricultural communities along the Snake River Valley as far east as Fruitland, Idaho near the Oregon border to Burley, Idaho, located in the central region of the state. Each residential location is mapped to the nearest sugarbeet or alfalfa field, and that distance varies from less than a mile to over 10 miles. Sugarbeets and alfalfa are commonly grown in the Snake River Valley and, in Idaho, the majority of these crops are genetically engineered to be herbicide-resistant and are thus often treated with glyphosate. The first aim of this project is to evaluate the relationship between residential proximity to glyphosate-treated fields and glyphosate exposure throughout the growing season. The second aim of this project is to understand the potential for diet to contribute to glyphosate exposure. To this end, Dr. Curl will be conducting a 2-week dietary intervention in this cohort in a crossover design. Each participant will be provided one week of conventional food and one week of organic food, randomized to order during June 2021. During this dietary intervention period, each study participant will provide daily urine samples to assess differences in pesticide exposure attributable to this dietary change. Recruitment for this project originally began in January 2020 and was intended to continue through May 2020. As of March 12, 2020, the WIC clinics had referred 17 eligible and interested participants; informed consent meetings and sample collection were underway. As originally designed, these meetings involved face-to-face interactions that had to be discontinued due to COVID-19, and as a result, the cohort was released and sample collection halted. Dr. Curl spent fall of 2020 redesigning the study to be fully contactless with no face-to-face interactions. All protocols and materials were revised, and some cases entirely re-created; videos were created (in English and Spanish) to provide remote instruction for sample collection procedures; new student researchers were hired; new IRB protocols were designed, submitted and approved; and new supplies were ordered to replace those used during the previous year. While the overall scope and aims of this project are unchanged, this supplement is requested to replace funds expended during the initial recruitment and to fund necessary modifications, in order to ensure project success.