1393-P: Potential Endocrine Disrupting Chemical Exposures among Rural Americans Using Remotely Collected Biosamples

Introduction & Objective: Rural residents experience higher rates of diabetes than their urban counterparts. Main identified causes to date include poor diet and physical inactivity. Given limited access to fresh foods, however, rural residents are also known to have high rates of canned food intake, potentially resulting in more exposure to bisphenols, which have been linked to diabetes.

Methods: To examine dietary chemical exposures, we collected urine samples among rural residents both in-person and remotely to measure bisphenols level. Day 0 samples were immediately frozen and transported on dry ice to prevent any chemical degradation. Rural residents then remotely collected three consecutive days of urine samples, froze samples at home, and mailed them back using insulated cold packs. We examined daily levels among 30 study participants and performed a preliminary investigation of whether bisphenol levels correlated with HbA1c results.

Results: Daily average bisphenol A (BPA) levels were 0.391 ng/mL on Day 0, 0.620 ng/mL on Day 1, 1.300 ng/mL on Day 2, and 1.088 ng/mL on Day 3. The intraclass correlation coefficient (ICC) for bisphenol A was 0.063 demonstrating very low correlation between daily values among study participants. We similarly found low ICC for bisphenol S at 0.238 and for bisphenol F at 0.095. We also found that all three study participants with a mean BPA higher than 2.00 ng/mL had prediabetes.

Conclusion: We found no significant degradation of bisphenols between immediately frozen Day 0 samples and those mailed on Day 1 to 3, demonstrating the feasibility of collecting biosamples remotely. The low correlation between daily levels suggests the need to collect several samples given high daily variability and short half-lives of these chemicals. Our preliminary analysis finds a possible association between high BPA exposure and poor glycemic control among rural Americans that merits further exploration in a larger study.