Traffic-related air pollution and perinatal mortality: a case-control study.
BACKGROUND
Ambient levels of air pollution may affect the health of children, as indicated by studies of infant and perinatal mortality. Scientific evidence has also correlated low birth weight and preterm birth, which are important determinants of perinatal death, 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.


OBJECTIVE
Our goal was to examine the association between traffic-related pollution and perinatal mortality.


METHODS
We used the information collected for a case-control study conducted in 14 districts in the City of São Paulo, Brazil, regarding risk factors for perinatal deaths. We geocoded the residential addresses of cases (fetal and early neonatal deaths) and controls (children who survived the 28th day of life) and 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 early neonatal death with higher exposure to traffic-related air pollution. Mothers exposed to the highest quartile of the DWTD compared with those less exposed exhibited approximately 50% increased risk (adjusted odds ratio = 1.47; 95% confidence interval, 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.
de Medeiros
Andréa Paula Peneluppi
AP
Department of Preventive Medicine, Faculty of Medicine, University of São Paulo, Brazil.
Gouveia
Nelson
N
Machado
Reinaldo Paul Pérez
RP
de Souza
Miriam Regina
MR
Alencar
Gizelton Pereira
GP
Novaes
Hillegonda Maria Dutilh
HM
de Almeida
Márcia Furquim
MF
D000397:Air Pollution; D001938:Brazil / Q000453:epidemiology; D016022:Case-Control Studies; D005313:Fetal Death / Q000453:epidemiology*; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D001335:Vehicle Emissions
D001335:Vehicle Emissions