Source-related components of fine particulate matter and risk of adverse birth outcomes in Northern Italy

Abstract Background /aim The aim of the present study was to assess the association between PM2.5, its sources, and preterm birth (PTB), low birth weight (LBW), and small for gestational age (SGA) in a large open residential cohort (Supersito Project in the Emilia-Romagna Region – Northern Italy). Methods We collected 2012–2014 pregnancy and childbirth data from Birth Assistance Certificates and selected the pregnancies of interest. PTBs (gestational age  Results The study included 23,708 neonates born to 23,415 women, among whom 1,311 PTB, 424 LBW, and 1,354 SGA occurred. PTB was the only outcome associated with PM2.5 mass (OR 1.03, 95% CI 1.002-1.058 per 1 μg/m3). Traffic, oil combustion and secondary sulfates and organics showed independent effects on PTB. Exposure to secondary nitrates was associated with a lower risk of PTB. There was no association between LBW or SGA and source-specific PM2.5 components or the residual PM2.5 related to all other sources. Conclusion This study found an association between PTB and PM2.5. Traffic, secondary sulfates, and organic and oil combustion were the sources with most consistent association.