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Background: Inhaling fine particles (particulate matter with diameter ≤ 2.5 μm; PM2.5) can induce oxidative stress and inflammation, and may contribute to onset of preterm labor and other adverse perinatal outcomes.

Objectives: We examined whether outdoor PM2.5 was associated with adverse birth outcomes among 22 countries in the World Health Organization Global Survey on Maternal and Perinatal Health from 2004 through 2008.

Methods: Long-term average (2001–2006) estimates of outdoor PM2.5 were assigned to 50-km–radius circular buffers around each health clinic where births occurred. We used generalized estimating equations to determine associations between clinic-level PM2.5 levels and preterm birth and low birth weight at the individual level, adjusting for seasonality and potential confounders at individual, clinic, and country levels. Country-specific associations were also investigated.

Results: Across all countries, adjusting for seasonality, PM2.5 was not associated with preterm birth, but was associated with low birth weight [odds ratio (OR) = 1.22; 95% CI: 1.07, 1.39 for fourth quartile of PM2.5 (> 20.2 μg/m3) compared with the first quartile (< 6.3 μg/m3)]. In China, the country with the largest PM2.5 range, preterm birth and low birth weight both were associated with the highest quartile of PM2.5 only, which suggests a possible threshold effect (OR = 2.54; CI: 1.42, 4.55 and OR = 1.99; CI: 1.06, 3.72 for preterm birth and low birth weight, respectively, for PM2.5 ≥ 36.5 μg/m3 compared with PM2.5 < 12.5 μg/m3). Conclusions: Outdoor PM2.5 concentrations were associated with low birth weight but not preterm birth. In rapidly developing countries, such as China, the highest levels of air pollution may be of concern for both outcomes.

Published Apr 1, 2014

Fleischer NL, Merialdi M, van Donkelaar A, Vadillo-Ortega F, Martin RV, Betran AP, Souza JP, O´Neill MS. 2014. Outdoor air pollution, preterm birth, and low birth weight: analysis of the World Health Organization Global Survey on Maternal and Perinatal Health. Environ Health Perspect 122:425–430;  http://dx.doi.org/10.1289/ehp.1306837

Polycyclic aromatic hydrocarbons (PAH) are major toxic air pollutants released during incomplete combustion of coal. PAH emissions are especially problematic in China because of their reliance on coal-powered energy. The prenatal period is a window of susceptibility to neurotoxicants. To determine the health benefits of reducing air pollution related to coal-burning, we compared molecular biomarkers of exposure and preclinical effects in umbilical cord blood to neurodevelopmental outcomes from two successive birth cohorts enrolled before and after a highly polluting, coal-fired power plant in Tongliang County, China had ceased operation. Women and their newborns in the two successive cohorts were enrolled at the time of delivery. We measured PAH-DNA adducts, a biomarker of PAH-exposure and DNA damage, and brain-derived neurotrophic factor (BDNF), a protein involved in neuronal growth, in umbilical cord blood. At age two, children were tested using the Gesell Developmental Schedules (GDS). The two cohorts were compared with respect to levels of both biomarkers in cord blood as well as developmental quotient (DQ) scores across 5 domains. Lower levels of PAH-DNA adducts, higher concentrations of the mature BDNF protein (mBDNF) and higher DQ scores were seen in the 2005 cohort enrolled after closure of the power plant. In the two cohorts combined, PAH-DNA adducts were inversely associated with mBDNF as well as scores for motor (p = 0.05), adaptive (p = 0.022), and average (p = 0.014) DQ. BDNF levels were positively associated with motor (p = 0.018), social (p = 0.001), and average (p = 0.017) DQ scores. The findings indicate that the closure of a coal-burning plant resulted in the reduction of PAH-DNA adducts in newborns and increased mBDNF levels that in turn, were positively associated with neurocognitive development. They provide further evidence of the direct benefits to children's health as a result of the coal plant shut down, supporting clean energy and environmental policies in China and elsewhere.

Published Mar 19, 2014

Tang, D., Lee, J., Muirhead, L., Li, T. Y., Qu, L., Yu, J., & Perera, F. (2014). Molecular and Neurodevelopmental Benefits to Children of Closure of a Coal Burning Power Plant in China. PLOS ONE, 9(3), e91966. https://doi.org/10.1371/JOURNAL.PONE.0091966

Introduction: The Port of Charleston, one of the busiest US ports, currently operates five terminals. The fifth terminal is being planned for expansion to accommodate container ships from the proposed Panama Canal expansion. Such expansion is expected to increase traffic within local vulnerable North Charleston neck communities by at least 7,000 diesel truck trips per day, more than a 70% increase from the present average rate of 10,000 trucks per day. Our objective was to measure the current particulate matter (PM) concentrations in North Charleston communities as a baseline to contrast against future air pollution after the proposed port expansion. Methods: Saturation study was performed to determine spatial variability of PM in local Charleston neck communities. In addition, the temporal trends in particulate air pollution within the region were determined across several decades. With the BGI sampler, PM samples were collected for 24 hours comparable to the federal reference method protocol. Gravimetric analysis of the PM filter samples was conducted following EPA protocol. Results: The range of the PM10 annual average across the region from 1982 to 2006 was 17.0-55.0 μg/m3. On only two occasions were the records of PM10 averaged above the 50.0 μg/m3 national standard. In the case of PM2.5, the annual average for 1999-2006 ranged from 11.0 to 13.5 μg/m3 and no annual average exceeded the 15.0 μg/m3 PM2.5 annual standard. Conclusions: Although ambient PM levels have fallen in the Charleston region since the 1960s due to aggressive monitoring by the stakeholders against air pollution, local air pollution sources within the North Charleston neck communities have consistently contributed to the PM levels in the region for several decades. This baseline assessment of ambient PM will allow for comparisons with future assessments to ascertain the impact of the increased truck and port traffic on PM concentrations.

Published Mar 12, 2014

Svendsen, E. R., Reynolds, S., Ogunsakin, O. A., Williams, E. M., Fraser-Rahim, H., Zhang, H., & Wilson, S. M. (2014). Assessment of Particulate Matter Levels in Vulnerable Communities in North Charleston, South Carolina prior to Port Expansion. Environmental Health Insights, 8, EHI.S12814. https://doi.org/10.4137/EHI.S12814

Long-term exposure to traffic pollution has been associated with adverse health outcomes in children and adolescents. A significant number of schools may be located near major roadways, potentially exposing millions of children to high levels of traffic pollution, but this hypothesis has not been evaluated nationally. We obtained data on the location and characteristics of 114,644 US public and private schools, grades prekindergarten through 12, and calculated their distance to the nearest major roadway. In 2005-2006, 3.2 million students (6.2%) attended 8,424 schools (7.3%) located within 100 m of a major roadway, and an additional 3.2 million (6.3%) students attended 8,555 (7.5%) schools located 100-250 m from a major roadway. Schools serving predominantly Black students were 18% (95% CI, 13-23%) more likely to be located within 250 m of a major roadway. Public schools eligible for Title I programs and those with a majority of students eligible for free/reduced price meals were also more likely to be near major roadways. In conclusion, 6.4 million US children attended schools within 250 m of a major roadway and were likely exposed to high levels of traffic pollution. Minority and underprivileged children were disproportionately affected, although some results varied regionally.

Published Feb 5, 2014

Kingsley, S. L., Eliot, M. N., Carlson, L., Finn, J., Macintosh, D. L., Suh, H. H., & Wellenius, G. A. (2014). Proximity of US schools to major roadways: A nationwide assessment. Journal of Exposure Science and Environmental Epidemiology, 24(3), 253–259. https://doi.org/10.1038/jes.2014.5

In addition to the morbidity and mortality concerns of outdoor air pollution, studies have shown that air pollution also generates problems for children's cognitive performance and human capital formation. High concentrations of pollutants can affect children's learning process by exacerbating respiratory illnesses, fatigue, absenteeism and attention problems. The purpose of this work is to analyze the possible contemporary effects of PM10 and other different air pollutants on standardized test scores in Chile. It examines results for 3,880 schools in the Metropolitan, Valparaiso and O’Higgins regions for children in fourth, eight and tenth grades between 1997 and 2012. Data for particulate matter (PM10 and PM2. 5), carbon monoxide (CO), nitrogen oxide (NOx) and ozone (O3) were interpolated at school level using a kriging methodology. The results suggest that higher annual P M10 and O3 levels are clearly associated with a reduction in test scores. Nonetheless, as of 2012 many municipalities in these Chilean regions are still exceeding the annual P M10 international standard quality norm (50 micrograms per cubic meter) by 15 micrograms per cubic meter on average. Efforts to reduce pollution below this norm in the most polluted municipalities would account for improvements in reading and math test scores of 3. 5 percent and 3. 1 percent of a standard deviation, respectively.

Published Dec 1, 2013

Miller;, S., & Vela, M. (2013). The Effects of Air Pollution on Educational Outcomes: Evidence from Chile. Inter-American Development Bank.

Background
Although studies suggest that exposure to pollutants is associated with race/ethnicity and socio-economic status (SES), many studies are limited to the geographic regions where monitoring stations are located.

Results
SES and race/ethnicity were related to predicted concentrations of both PM2.5 and O3 for census tracts in North Carolina. Lower SES and higher proportion minority population were associated with higher levels of PM2.5. An interquartile range (IQR) increase of median household income reduced the predicted average PM2.5 level by 0.10 µg/m3. The opposite relationship was true for O3. An IQR increase of median household income increased the predicted average O3 measure by 0.11 ppb.

Conclusions
The analyses demonstrate that SES and race/ethnicity are related to predicted estimates of PM2.5 and O3 for census tracts in North Carolina. These findings offer a baseline for future exposure modeling work involving SES and air pollution for the entire state and not just among the populations residing near monitoring networks.

Published Oct 1, 2013

Gray, S. C., Edwards, S. E., & Miranda, M. L. (2013). Race, socioeconomic status, and air pollution exposure in North Carolina. Environmental Research, 126, 152–158. https://doi.org/10.1016/j.envres.2013.06.005

Climate change is a health threat no less consequential than cigarette smoking. Increased concentrations of greenhouse gases, and especially CO 2, in the earth's atmosphere have already warmed the planet substantially, causing more severe and prolonged heat waves, temperature variability, air pollution, forest fires, droughts, and floods, all of which put respiratory health at risk. These changes in climate and air quality substantially increase respiratory morbidity and mortality for patients with common chronic lung diseases such as asthma and COPD and other serious lung diseases. Physicians have a vital role in addressing climate change, just as they did with tobacco, by communicating how climate change is a serious, but remediable, hazard to their patients. © 2013 American College of Chest Physicians.

Published May 1, 2013

Bernstein, A. S., & Rice, M. B. (2013). Lungs in a warming world: Climate change and respiratory health. Chest, 143(5), 1455–1459. https://doi.org/10.1378/chest.12-2384

Although many time-series studies of ozone and mortality have identified positive associations, others have yielded null or inconclusive results, making the results of these studies difficult to interpret. METHODS We performed a meta-analysis of 144 effect estimates from 39 time-series studies, and estimated pooled effects by lags, age groups, cause-specific mortality, and concentration metrics. We compared results with pooled estimates from the National Morbidity, Mortality, and Air Pollution Study (NMMAPS), a time-series study of 95 large U.S. urban centers from 1987 to 2000. RESULTS Both meta-analysis and NMMAPS results provided strong evidence of a short-term association between ozone and mortality, with larger effects for cardiovascular and respiratory mortality, the elderly, and current-day ozone exposure. In both analyses, results were insensitive to adjustment for particulate matter and model specifications. In the meta-analysis, a 10-ppb increase in daily ozone at single-day or 2-day average of lags 0, 1, or 2 days was associated with an 0.87% increase in total mortality (95% posterior interval = 0.55% to 1.18%), whereas the lag 0 NMMAPS estimate is 0.25% (0.12% to 0.39%). Several findings indicate possible publication bias: meta-analysis results were consistently larger than those from NMMAPS; meta-analysis pooled estimates at lags 0 or 1 were larger when only a single lag was reported than when estimates for multiple lags were reported; and heterogeneity of city-specific estimates in the meta-analysis were larger than with NMMAPS. CONCLUSIONS This study provides evidence of short-term associations between ozone and mortality as well as evidence of publication bias.

Published Feb 25, 2013

Bell, M. L., Dominici, F., & Samet, J. M. (2005). A meta-analysis of time-series studies of ozone and mortality with comparison to the national morbidity, mortality, and air pollution study. Epidemiology (Cambridge, Mass.), 16(4), 436–445. https://doi.org/10.1097/01.ede.0000165817.40152.85

Childhood cognitive and test-taking abilities have long-term implications for educational achievement and health, and may be influenced by household environmental exposures and neighborhood contexts. This study evaluates whether age 5 scores on the Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R, administered in English) are associated with polycyclic aromatic hydrocarbon (PAH) exposure and neighborhood context variables including poverty, low educational attainment, low English language proficiency, and inadequate plumbing. The Columbia Center for Children's Environmental Health enrolled African-American and Dominican-American New York City women during pregnancy, and conducted follow-up for subsequent childhood health outcomes including cognitive test scores. Individual outcomes were linked to data characterizing 1-km network buffers around prenatal addresses, home observations, interviews, and prenatal PAH exposure data from personal air monitors. Prenatal PAH exposure above the median predicted 3.5 point lower total WPPSI-R scores and 3.9 point lower verbal scores; the association was similar in magnitude across models with adjustments for neighborhood characteristics. Neighborhood-level low English proficiency was independently associated with 2.3 point lower mean total WPPSI-R score, 1.2 point lower verbal score, and 2.7 point lower performance score per standard deviation. Low neighborhood-level educational attainment was also associated with 2.0 point lower performance scores. In models examining effect modification, neighborhood associations were similar or diminished among the high PAH exposure group, as compared with the low PAH exposure group. Early life exposure to personal PAH exposure or selected neighborhood-level social contexts may predict lower cognitive test scores. However, these results may reflect limited geographic exposure variation and limited generalizability. © 2013 Springer Science+Business Media New York.

Published Feb 20, 2013

Lovasi, G. S., Eldred-Skemp, N., Quinn, J. W., Chang, H. wen, Rauh, V. A., Rundle, A., Orjuela, M. A., & Perera, F. P. (2014). Neighborhood Social Context and Individual Polycyclic Aromatic Hydrocarbon Exposures Associated with Child Cognitive Test Scores. Journal of Child and Family Studies, 23(5), 785–799. https://doi.org/10.1007/s10826-013-9731-4

In recent years, several studies show that people who live, work or attend school near the main roadways have an increased incidence and severity of health problems that may be related with traffic emissions of air pollutants. The concentrations of near-road atmospheric pollutants vary depending on traffic patterns, environmental conditions, topography and the presence of roadside structures. In this study, the vertical and horizontal variation of nitrogen dioxide (NO2) and benzene (C6H6) concentration along a major city ring motorway were analysed. The main goal of this study is to try to establish a distance from this urban motorway considered " safe" concerning the air pollutants human heath limit values and to study the influence of the different forcing factors of the near road air pollutants transport and dispersion. Statistic significant differences (p=0.001, Kruskal-Wallis test) were observed between sub-domains for NO2 representing different conditions of traffic emission and pollutants dispersion, but not for C6H6 (p=0.335). Results also suggest significant lower concentrations recorded at 100m away from roadway than at the roadside for all campaigns (p<0.016 (NO2) and p<0.036 (C6H6), Mann-Whitney test). In order to have a " safe" life in homes located near motorways, the outdoor concentrations of NO2 must not exceed 44-60.0μgm3 and C6H6 must not exceed 1.4-3.3μgm3. However, at 100m away from roadway, 81.8% of NO2 receptors exceed the annual limit value of human health protection (40μgm3) and at the roadside this value goes up to 95.5%. These findings suggest that the safe distance to an urban motorway roadside should be more at least 100m. This distance should be further studied before being used as a reference to develop articulated urban mobility and planning policies. © 2013 Elsevier Ltd.

Published Jan 21, 2013

Barros, N., Fontes, T., Silva, M. P., & Manso, M. C. (2013). How wide should be the adjacent area to an urban motorway to prevent potential health impacts from traffic emissions? Transportation Research Part A: Policy and Practice, 50, 113–128. https://doi.org/10.1016/j.tra.2013.01.021