Ambient air pollution and thyroid function in Spanish adults. A nationwide population-based study (Di@bet.es study).

Recent reports have suggested that air pollution may impact thyroid function, although the evidence is still scarce and inconclusive. In this study we evaluated the association of exposure to air pollutants to thyroid function parameters in a nationwide sample representative of the adult population of Spain. The Di@bet.es study is a national, cross-sectional, population-based survey which was conducted in 2008-2010 using a random cluster sampling of the Spanish population. The present analyses included 3859 individuals, without a previous thyroid disease diagnosis, and with negative thyroid peroxidase antibodies (TPO Abs) and thyroid-stimulating hormone (TSH) levels of 0.1-20 mIU/L. Participants were assigned air pollution concentrations for particulate matter In multivariate linear regression models, there was a highly significant negative correlation between PM2.5 concentrations and both FT4 (p Exposures to PM2.5 in the general population were associated with mild alterations in thyroid function