BackgroundAmbient 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.ObjectivesOur goal was to examine the association between traffic-related pollution and perinatal mortality.MethodsWe 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.ResultsLogistic 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.ConclusionsThese results suggest that motor vehicle exhaust exposures may be a risk factor for perinatal mortality.

ObjectiveAir pollution has been investigated as a potential determinant for low birthweight. The aim of the present study was to study the effect of air pollution on birthweight. MethodsWe analyzed all deliveries by mothers living in the municipality of São Paulo, Southeastern Brazil, between 1998 and 2000. We estimated the prevalence of low birthweight according to newborn, mother, and delivery characteristics. Only births occurring in the most central districts of the city were analyzed, totaling 311.735 events. For the evaluation of the effects of air pollution, we excluded preterm and multiple deliveries. Pollutants analyzed were ozone (O 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), suspended particles (PM 10 ), and carbon monoxide (CO). The effect of maternal exposure to air pollution on birthweight was evaluated using linear and logistic regression. Results A total of 4.6% of newborns weighed less than 2,500 g at birth. Maternal exposure to CO, PM 10 , and NO 2 during the first trimester of pregnancy was significantly associated with decreased birthweight. ConclusionsOur results reinforce the notion that maternal exposure to air pollution during the first trimester of pregnancy may contribute to lesser weight gain in the fetus.

A poluição atmosférica é uma das maiores preocupações para a saúde pública. Entre os estudos conduzidos para testar a associação entre poluição do ar e os mais diversos desfechos em saúde, alguns utilizaram dados viários e de tráfego veicular como avaliação da exposição. O presente trabalho pretende revisar e discutir alguns dos aspectos metodológicos dos estudos que utilizaram este método, principalmente em áreas onde a fonte veicular é uma grande geradora de poluentes. Realizou-se uma busca bibliográfica com palavras-chave relacionadas à poluição atmosférica e tráfego veicular, e foram selecionados artigos publicados entre os anos de 2000 e 2009. Foram constatadas várias abordagens para avaliar a exposição, enfatizando-se o método da Densidade de Tráfego Ponderada pela Distância, que considera as vias e a distância das mesmas em relação ao local de interesse e o tráfego. Além disso, destaca-se a importância do uso de técnicas de sistemas de informação geográfica (SIG) como instrumento na construção de modelos para mensurar a exposição.

Objective: To identify spatial patterns in rates of admission for pneumonia among children and relate them to the number of fires reported in the state of Mato Grosso, Brazil. Methods:We conducted an ecological and exploratory study of data from the state of Mato Grosso for 2008 and 2009 on hospital admissions of children aged 0 to 4 years due to pneumonia and on fires in the same period. Admission rates were calculated and choropleth maps were plotted for rates and for fire outbreaks, Moran's I was calculated and the kernel estimator used to identify "hotspots." Data were analyzed using TerraView 3.3.1. Results:Fifteen thousand six hundred eighty-nine children were hospitalized (range zero to 2,315), and there were 161,785 fires (range 7 to 6,454). The average rate of admissions per 1,000 inhabitants was 2.89 (standard deviation [SD] = 5.18) and the number of fires per 1,000 inhabitants was 152.81 (SD = 199.91). Moran's I for the overall number of admissions was I = 0.02 (p = 0.26), the index for rate of admission was I = 0.02 (p = 0.21) and the index for the number of fires was I = 0.31 (p < 0.01). It proved possible to identify four municipalities with elevated rates of admissions for pneumonia. It was also possible to identify two regions with high admission densities. A clustering of fires was evident along what is known as the "arc of deforestation." Conclusions:This study identified municipalities in the state of Mato Grosso that require interventions to reduce rates of admission due to pneumonia and the number fires.J Pediatr (Rio J). 2012;88(2):177-83: Pneumonia, geographic information system, fires, biomass burning, ecological studies. ResumoObjetivo: Identificar padrões espaciais para taxas de internação por pneumonia em crianças e para focos de queimada no estado do Mato Grosso. Metodologia:Foi realizado um estudo ecológico e exploratório com dados de internação de pneumonia em criança de 0 a 4 anos e de focos de queimada para o estado do Mato Grosso relativos aos anos de 2008 e 2009. Foram criadas taxas de internação, construídos mapas temáticos para essas taxas e para focos de queimada e obtidos os índice de Moran global e estimador de Kernel para as taxas e focos de queimada. Os dados foram analisados pelo programa TerraView 3.3.1.Resultados: Foram 15.689 internações (variando de zero a 2.315) e 161.785 focos de queimadas (variando de sete a 6.454). A taxa média de internação por 1.000 habitantes foi de 2,89 [desvio padrão = 5,18] e de queimadas por 1.000 habitantes foi de 152,81 (desvio padrão = 199,91). O índice de Moran global para o número de internações foi de 0,02 (p = 0,26), para a taxa de internação foi de 0,02 (p-valor = 0,21), e de 0,31 (p-valor < 0,01) para focos de queimadas. Foi possível identificar quatro municípios com elevadas taxas de internação por pneumonia e identificar duas regiões com altas densidades de internação. Ficou evidente um adensamento de focos de queimadas no chamado arco de desmatamento. Conclusões:Este estudo permitiu identificar municípios que necessitam...