Gestational hypertension, preeclampsia, and gestational diabetes mellitus after high exposure to perfluoroalkyl substances from drinking water in Ronneby, Sweden.

BACKGROUND: Leakage of fire-fighting foam from an airfield caused contamination of the drinking water supplied to a third of the population in Ronneby, resulting in very high serum levels of predominantly perfluorooctane sulfonate (PFOS) and perfluorohexane sulfonate (PFHxS). The results of studies investigating the association between exposure to perfluorinated alkyl substances (PFAS) and pregnancy complications are inconsistent, and studies at high exposures of PFOS and PFHxS are lacking. OBJECTIVES: To investigate the association between exposure to high levels of PFAS and gestational hypertension and preeclampsia, and gestational diabetes mellitus. METHODS: We retrieved data on 27 292 childbirths between 1995 and 2013 from the National Medical Birth Register for women that had a residential address in Blekinge county for at least one year before delivery. Residential history was used as a proxy for exposure by categorizing women into high-, intermediate-, or background exposed based on their residential address during the five-year period before childbirth. Data on confounders were retrieved from administrative registers. The outcomes were defined based on International Classification of Diseases codes. We used logistic regression to estimate odds ratios (OR) for gestational hypertension and preeclampsia, and gestational diabetes mellitus. We also investigated effect modification by fetal sex. RESULTS: We found no evidence of increased risk of gestational hypertension and preeclampsia (OR 0.80; CI 0.63-1.03), nor gestational diabetes (OR 1.03; CI 0.67-1.58) after high PFAS exposure. There was no effect modification by fetal sex. DISCUSSION: This was the first study to investigate the association between high exposure to PFOS and PFHxS and pregnancy complications. The results from this study add important knowledge to public health management as new hotspots with high levels of PFAS are continuously discovered.

Developmental language disorders in preschool children after high exposure to perfluoroalkyl substances from contaminated drinking water in Ronneby, Sweden.

There are indications that early-life exposure to perfluoroalkyl substances (PFAS) can impact neurodevelopment, but results are inconclusive. The objective was to investigate if high early-life exposure to primarily perfluorohexanesulfonic acid (PFHxS) and perfluorooctanesulfonic acid (PFOS) increases the risk of developmental language disorder in children up to seven years of age. Methods: A register-based cohort of all children born 1998-2013 in Blekinge county, Sweden, was studied. Maternal residential history, that is, with or without highly PFAS-contaminated drinking water, during the 5-year period before childbirth was used as a proxy for early-life exposure. Exposure was categorized as high (n = 646), intermediate (n = 1,650), or background (n = 9,599). We used Cox proportional hazards regression to estimate hazard ratios (HR) for (1) referral to a speech- and language pathologist after routine screening at Child Health Services, and (2) subsequent language disorder diagnosis after clinical assessment. Models were adjusted for parity, maternal age, education level, and smoking, and explored effect modification by sex. Results: In children from the high-exposed area, the adjusted HR for referral was 1.23 (95% CI = 1.03, 1.47) and 1.13 (95% CI = 0.97, 1.56) for subsequent diagnosis. There was no increased risk in the intermediate exposure category. Conclusion: Children, particularly girls, with high exposure had an increased risk of both referral and confirmed developmental language disorder. Further research is needed on PFAS in the context of general neurodevelopment, for which language development is a proxy.