Adverse reproductive outcomes associated with exposure to a municipal solid waste incinerator.

Introduction: The association between reproductive health outcomes and exposure to municipal solid waste incinerators (MSWIs) is inconclusive. This study investigates the association between exposure to a MSWI and various reproductive outcomes (preterm birth, low birth weight, small for gestational age, and sex ratio), taking into account other sources of pollution (industrial plants, highway, major roads with high traffic flows) and maternal factors, including the socioeconomic status.

Methods: PM10 concentration maps were used for the exposure assessment to the MSWI and to other sources of pollution in the study area. Information on resident births and maternal covariates were selected from the delivery certificates referred to the period 2001-2010. Mothers' addresses were geocoded in order to attribute the individual level of exposure. Odds ratios (ORs) with a 95% confidence interval (CI) adjusted for maternal covariates and exposure to other pollution sources were calculated.

Results: A total of 3153 newborns to 2401 mothers residing in area during the study period were analyzed. A risk of preterm birth associated with increased exposure was detected (OR = 1.61; 95% CI: 0.88-2.94; p test for trend 0.098). When newborns to primiparous women were considered an OR of 2.18 (95% CI: 1.05-4.53) and a significant trend were observed (p = 0.033). No significant results for the other investigated outcomes were observed.

Conclusions: The study detected a slight association between exposure at MSWI and preterm births. The results are in agreement with those of a previous multi-site study with similar design, and they strengthen the recommendation to consider gestational age in studies and surveillance in areas with MSWIs and similar sources of pollution.