Exposure to PFOA and birth outcome in North Rhine-Westphalia, Germany

Introduction Perfluorooctanoic acid (PFOA) is a widespread persistent organic pollutant. Human exposure mainly occurs via consumption of food and water. In 2006, more than 4 million residents have been exposed to PFOA-contaminated drinking water. In cooperation with the Perinatal Quality Registry and the State Water Authority, a project was established to evaluate the impact of maternal PFOA-exposure on birth weight and other birth outcome variables. Here we report on the current status of this project. Methods The drinking water database is a compilation of state-wide PFOA-monitoring data for 193 water supply areas between 2006 and 2014. Maternal and perinatal characteristics are derived from the Perinatal Quality Registry (zip-code related). Data have been checked for plausibility, descriptive statistics are conducted. Simple and multiple regression analyses are performed. To relate PFOA concentrations to zip-areas, different approaches of spatial realignment (e.g. Bayesian modelling, Kriging) are applied. Results More than 35,000 drinking water samples have been analysed between 2006 and 2014. PFOA-concentrations range from below limit of quantification (LOQ = 10 ng/l) to 640 ng/l. After application of exclusion criteria 1,545,102 births are selected from 2003 to 2014. Mean birth weight is 3331 g (standard deviation = 587 g). Characteristics such as gestational age and weight gain, mother’s height and weight, smoking status, child’s sex and parity are identified as covariates for multiple regression (adjusted R² = 0.43). Conclusions Birth outcome was successfully linked to PFOA-exposure data, resulting in a total of 613,868 complete datasets. Further statistics will include bivariate analyses and Markov random field models.