Traffic Related Air Pollution and Perinatal Mortality: a Case-Control Study
de Medeiros APP, Gouveia N, Machado RPP, de Souza MR, Alencar GP, Novaes HMD, de Almeida MF. 2008. Environ Health Perspect: doi:10.1289/ehp.11679. [Online 22 September 2008]
ABSTRACT
Background: ambient levels of air pollution may affect the health of children as indicated by
studies on infant and perinatal mortality. Scientific evidence also implicated low birth weight
and preterm birth, which are important determinants of perinatal deaths, with air pollution.
However, most of these studies used ambient concentrations measured at monitoring sites
which may not consider differential exposure to pollutants found at elevated concentrations
near heavy-traffic roadways.
studies on infant and perinatal mortality. Scientific evidence also implicated low birth weight
and preterm birth, which are important determinants of perinatal deaths, with air pollution.
However, most of these studies used ambient concentrations measured at monitoring sites
which may not consider differential exposure to pollutants found at elevated concentrations
near heavy-traffic roadways.
Objectives: to examine the association between traffic-related pollution and perinatal mortality
Methods: we used the information collected on a case-control study conducted in 14 districts
in the City of São Paulo, Brazil, regarding risk factors for perinatal deaths. The residential
addresses of cases (fetal and early neonatal deaths) and controls (children that survived the
28th day of life) were geocoded and we calculated a Distance-Weighted Traffic Density
(DWTD) measure considering all roads contained in a buffer surrounding these homes.
Results: logistic regression revealed a gradient of increasing risk of an early neonatal death
with higher exposure to traffic-related air pollution. Mothers exposed to highest quartile of the
DWTD compared to those less exposed exhibited approximately 50% increased risk (ORadj=
1.47 (CI 95% 0.67 – 3.19). Associations for fetal mortality were less consistent.
with higher exposure to traffic-related air pollution. Mothers exposed to highest quartile of the
DWTD compared to those less exposed exhibited approximately 50% increased risk (ORadj=
1.47 (CI 95% 0.67 – 3.19). Associations for fetal mortality were less consistent.
Conclusions: These results suggest that motor vehicle exhaust exposures may be a risk
factor for perinatal mortality.
factor for perinatal mortality.
