Does prenatal exposure to multiple airborne and tap-water pollutants increase neonatal thyroid-stimulating hormone concentrations? Data from the Picardy region, France

Systematic screening for congenital hypothyroidism by heel-stick sampling has revealed unexpected heterogeneity in the geographic distribution of newborn thyroid-stimulating hormone concentrations in Picardy, France. We explored a possible relationship with environmental pollutants. Zip code geolocation data from mothers of newborns without congenital hypothyroidism born in 2021 were linked to ecological data for a set of airborne (particulate matter with a diameter of 2.5 μm or less [PM2.5] or 10 μm or less [PM10]) and tap-water (nitrate and perchlorate ions and atrazine) pollutants. Statistical associations between mean exposure levels during the third trimester of pregnancy and Thyroid-stimulating hormone (TSH) concentrations in 6249 newborns (51 % male) were investigated using linear regression models. Median neonatal TSH concentration (interquartile range, IQR) was 1.7 (1–2.8) mIU/L. An increase of one IQR in prenatal exposure to perchlorate ions (3.6 μg/L), nitrate ions (19.2 mg/L), PM2.5 (3.7 μg/m3) and PM10 (3.4 μg/m3), were associated with increases in TSH concentrations of 2.30 % (95 % CI: 0.95–3.66), 5.84 % (95 % CI: 2.81–8.87), 13.44 % (95 % CI: 9.65–17.28) and 6.26 % (95 % CI: 3.01–9.56), respectively. Prenatal exposure to perchlorate and nitrate ions in tap water and to airborne PM over the third trimester of pregnancy was significantly associated with increased neonatal TSH concentrations. [Display omitted] •Spatial distribution of neonatal TSH levels is heterogeneous in Picardy, France.•Environmental pollutants could impact neonatal TSH levels.•Evaluation of exposure to certain pollutants in the third trimester of pregnancy•Prenatal exposure to perchlorate and nitrate increased neonatal TSH levels.•Prenatal exposure to particulate matter increased neonatal TSH levels.