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Background: The characterisation of individual exposure to air pollution in urban scenarios is a challenge in environmental epidemiological studies. We investigated if the city's pollution monitoring stations over or underestimate the exposure of individuals depending on their socioeconomic conditions and daily commuting times. Methods: The amount of black carbon accumulated in the lungs of 604 deceased who underwent autopsy in São Paulo was considered as a proxy for PM10. The concentrations of PM10 in the residence of the deceased were estimated by interpolating an ordinary kriging model. These two-exposure metrics allowed us to construct an environmental exposure misclassification index ranging from -1 to 1. The association between the index and daily commuting, socioeconomic context index (GeoSES), and street density as predictors was assessed by means of a multilevel linear regression model. Findings: With a decrease of 0.1 units in GeoSES, the index increases, on average, by 0.028 units and with an increase of 1 h in daily commuting, the index increases, on average, by 0.022 units indicating that individual exposure to air pollution is underestimated in the lower GeoSES and in people with many hours spent in daily commuting. Interpretation: Reduction of health consequences of air pollution demands not only alternative fuel and more efficient mobility strategies, but also should include profound rethink of cities. Funding: São Paulo Research Foundation (FAPESP-13/21728-2) and National Council for Scientific and Technological Development (CNPq-304126/2015-2, 401825/2020-5).
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BACKGROUND: Hypertension and air pollution are two important risk factors for cardiovascular morbidity and mortality. Although several studies suggest that air pollution has a significant impact on blood pressure, studies on long-term effects are sparse and still controversial. OBJECTIVE: To evaluate the effects of exposure of outdoor workers to different levels of traffic-generated PM2.5 on blood pressure. DESIGN: This is an observational panel study. PARTICIPANTS: 88 non-smoking workers exposed to different concentrations of air pollution were evaluated weekly along four successive weeks. MEASUREMENTS: In each week, personal monitoring of 24-h PM2.5 concentration and 24-h ambulatory blood pressure were measured. The association between blood pressure variables and PM2.5, adjusted for age, body mass index, time in job, daily work hours, diabetes, hypertension and cholesterol was assessed by means of multiple linear regression models fitted by least squares. RESULTS: Exposure to PM2.5 (ranging from 8.5 to 89.7⯵g/m3) is significantly and consistently associated with an increase in average blood pressure. An elevation of 10⯵g/m3 in the concentration of PM2.5 is associated with increments of 3.9â¯mm Hg (CI 95%â¯=â¯[1.5; 6.3]) in average systolic 24-h blood pressure for hypertensive and/or diabetic workers. CONCLUSION: Exposure to fine particles, predominantly from vehicular traffic, is associated with elevated blood pressure in hypertensive and/or diabetic workers.
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Contaminantes Atmosféricos , Contaminación del Aire/estadística & datos numéricos , Presión Sanguínea , Hipertensión/epidemiología , Exposición Profesional/estadística & datos numéricos , Monitoreo Ambulatorio de la Presión Arterial , Exposición a Riesgos Ambientales , Humanos , Material ParticuladoRESUMEN
The concern about environmental pollution has risen in the last decades because of its effects on human's health. However, evaluation of the exposure to certain pollutants is currently hampered by the availability of past environmental data. Tree rings are an alternative to reconstruct environmental variability of pre-instrumental periods. Nevertheless, this approach has some reported limitations including migration of chemical elements in the tree rings. The aim of this study was to evaluate the distribution of Cd, Cu, Hg, Na, Ni, Pb, Zn in the tree rings of Tipuana tipu (Fabaceae) to aid the reconstruction of past environmental pollution. We sampled trees in the central region of the city of São Paulo, Brazil, and scanned their tree rings using LA-ICP-MS. We used these data to evaluate the temporal trends of chemical elements under investigation. Results show a non-random distribution of these chemical elements within the tree rings, with higher content in the cell-walls of vessels and lower content in the fibers. Sodium was the only element intimately related to the axial parenchyma cells. Due to differences in elemental composition of xylem cells, temporal trends where evaluated using distinct quartiles of data distribution in each tree ring. The first quartile represents the lower content found in fibers and parenchyma, while the third quartile corresponds to the higher content found in vessels. Data from vessels better represent the decreasing trend of Cd, Cu, Pb, and Ni in the last three decades. This reduction is less significant for Na and Zn. Our results highlight the potential to improve the records of environmental pollution using data from different cells. Pronounced reduction in Pb may be attributed to the lead phase-out in gasoline, while the decreasing trend of Cd, Cu, Ni pollution is probably related to increasing efficiency of vehicles and the deindustrialization of São Paulo. Chemical elements are non-randomly distributed in tree rings. Chemical content of vessels cell-walls is a reliable record of metal pollution, which is decreasing in São Paulo.
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Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Contaminación Ambiental/estadística & datos numéricos , Metales Pesados/análisis , Árboles/química , Brasil , Contaminación Ambiental/análisis , Humanos , PlomoRESUMEN
In this study, the effects of aerobic exercise on the upper airways and their defense mechanisms were investigated in athletes. The athletes ran in two different environments: the downtown streets of the city of São Paulo (Street), more polluted, and an urban forest (Forest), less polluted. Thirty-eight young healthy athletes ran for 45 min d-1 randomly during five consecutive days, with an interval of 48 h before changing environment. Clinical parameters and respiratory tract defense markers were evaluated before and after the first run on Mondays (1 d) and on Fridays (5 d). Street presented higher mean PM2.5 concentrations (65.1 ± 39.1 µg m-3, p < 0.001) and lower temperature (22.0 °C, p = 0.010) than Forest (22.6 ± 15.3 µg m-3 and 22.8 °C). After 1 d Street running, subjects showed an increment in heart rate (p < 0.001). At day 5, there was twice the number of athletes with impaired nasal mucociliary clearance (MCC) in the Street runners group when compared to the Forest runners group. Exhaled breath condensate pH values increased in the Forest group, with significant differences between groups in day 1 (p = 0.006) and day 5 (p < 0.001), despite the fact that both groups showed values within the normal range. After exposure to both environments, the number of cells in the nasal lavage fluid was reduced after exercise (p = 0.014), without alterations in cell type and IL-8 and IL-10 concentrations. Aerobic exercise can either maintain or acutely enhance MCC and it may help to regulate inflammatory responses in the airways. Here we show that exercise practice in polluted outdoor environment, over a 5 d period, impairs MCC. In contrast, athletes running in the less polluted environment (Forest) show higher exhaled breath condensate pH values when compared to those who exercised in a more polluted environment (Street).