Impact of air pollution on pulmonary function and respiratory symptoms in children. Longitudinal repeated-measures study.

BACKGROUND: Salamanca, Mexico occupied fourth place nationally in contaminating emissions. The aim of the study was to determine the impact of air pollution on the frequency of pulmonary function alterations and respiratory symptoms in school-age children in a longitudinal repeated-measures study. METHODS: We recruited a cohort of 464 children from 6 to 14 years of age, from two schools differing in distance from the major stationary air pollution sources. Spirometry, respiratory symptoms and air pollutants (O3, SO2, NO, NO2, NOx, PM10,) were obtained for each season. Mixed models for continuous variables and multilevel logistic regression for respiratory symptoms were fitted taking into account seasonal variations in health effects according to air pollution levels. RESULTS: Abnormalities in lung function and frequency of respiratory symptoms were higher in the school closer to major stationary air pollution sources than in the distant school. However, in winter differences on health disappeared. The principal alteration in lung function was the obstructive type, which frequency was greater in those students with greater exposure (10.4% vs. 5.3%; OR = 1.95, 95% CI 1.0-3.7), followed by the mixed pattern also more frequent in the same students (4.1% vs. 0.9%; OR = 4.69, 95% CI, 1.0-21.1). PM10 levels were the most consistent factor with a negative relationship with FVC, FEV1 and PEF but with a positive relationship with FEV1/FVC coefficient according to its change per 3-month period. CONCLUSIONS: Students from the school closer to major stationary air pollution sources had in general more respiratory symptoms than those from the distant school. However, in winter air pollution was generalized in this city and differences in health disappeared. PM10 levels were the most consistent factor related to pulmonary function according, to its change per 3-month period.

Repercussões clínicas da exposição à poluição atmosférica / Clinical repercussions of exposure to atmospheric pollution

A poluição atmosférica é um assunto exaustivamente discutido mundialmente. As repercussões clínicas decorrentes das exposições aos principais poluentes atmosféricos são apresentadas resumidamente. Os padrões de qualidade do ar para esses agentes, segundo a Agência de Proteção Ambiental Americana, estão descritos em relação aos seus valores primários e tempo médio. Os efeitos respiratórios conseqüentes à queima de combustíveis fósseis e de biomassa são apresentados de forma sucinta visando, essencialmente, a alertar os profissionais da saúde para o aumento da morbidade relacionada com a poluição ambiental.

Atmospheric pollution is a topic of extensive discussion the world over. The clinical repercussions of exposure to the principal atmospheric pollutants are summarized herein. According to the American Environmental Protection Agency, air quality standards for these agents are set based on their primary and half-life values. The respiratory effects of the burning of fossil fuels and biomass are succinctly presented, with a special focus on alerting health care professionals of the increased morbidity related to environmental pollution.

Exposure to environmental chemicals relevant for respiratory hypersensitivity: global aspects.

Trends of air pollutant concentrations that influence the incidence of respiratory diseases and might be influential for respiratory hypersensitivity are presented and discussed. Data for these trends are collected in UNEP/WHO's Global Environmental Monitoring System GEMS/Air which recently has been revitalized and redirected to become a tool for providing the information necessary for rational air quality management. Data are interpreted with respect to WHO's most recent air quality guidelines, which are an update of the air quality guidelines for Europe published in 1987. A WHO study on the global disease burden and the contribution of air pollution to it is discussed and global estimates of mortality resulting from air pollution through sulphur dioxide and suspended particulate matter, by different economic regions, are given. Starting from the air quality guidelines still valid at the time of publication of the update, about 460,000 excess deaths globally are due to suspended particulate matter and about 370,000 to sulphur dioxide.

Influencia de la contaminación atmosférica en la calidad de aire de interiores / Influence of outdoor pollution on indoor air quality

The influence of outdoor pollution on indoor air quality was studied in downtown Santiago (Bandera street). Carbon monoxide (CO), nicotine, particulate matter, respirable fraction (PM5) and total and carcinogenic polyaromatic hydrocarbons (PAHs) were simultaneously monitores indoors and outdoors and indoors in restaurants, offices and other places. The levels of CO changed simultaneously outdoors and indoors (r=0.89) specially during traffic rush hours, demonstrating the importance of outdoor infiltration into the indoor air quality and masking the contribution of other CO indoor sources. The maximun CO concentrations were over 800 percent and over 1000 percent higher indoors and outdoors respectively than the 9 ppm CO National Ambient Air Quality. The PM5 concentrations were very high and showed no significant differences (p>0.05) from indoor to outdoors, or between indoor levels in restaurants, offices and other places. Total ans carcinogenic PAHs levels were also very high, outdoors and indoors, outodoor levels being generally higher than those indoors and no significant; differences (p>0.05) were found for the indoor levels between restaurants, offices and other places. Nicotine levels showed significant differences (p<0.05) between indoor and outdoor levels. In addition, great differences (p<0.05) in indoor levels, were found between offices and restaurants, and offices and other places. Among indoor sources cigarrete smoke seems to be a minor source since nicotine concentrations, bieng 2.3 times higher in restaurants and other places than in offices, do not contribute to enhance significantly PM5 and total and carcinogenic HAPs in the first ones. These results suggest that in downtown Santiago, infiltration might be the main source of indoor pollution. This is supported by 2 evidences: a) coronene, a tracer of vehicle emissions was found in high concentraion indoors and b) in restaurants (in wich PAHs emissions might be higher indoor) a correlation coefficient of 0.987 for the indoor and outdoor concentrations of carcinogenic PAHs was found. Furthermore a survey asking for different symptoms and effects probably related to air pollution was made to people working in Bandera and in a rural area located 40 Km from Santiago. The results showed that excluding smoking as a confounded factor, people working in Bandera showed a significantly greater (p<0.05) risk of ill effects on their health than people working in the rural area

Efectos de la contaminación del ambiente sobre la salud respiratoria / Effects of environmental contamination on respiratory health

A partir de la década de los 50, las ciudades industrializadas y grandes urbes en el mundo confrontaron un nuevo problema de salud pública "LA CONTAMINACION AMBIENTAL", las consecuencias sobre el desarrollo y la salud de los seres vivos a largo plazo no se conocen con precisión, sin embargo de acuerdo al tipo, cantidad y mecanismo de acción del contaminante sus efectos pueden ser irreversibles o mortales. En México la contaminación del aire en la zona metropolitana representa uno de los principales problemas de salud por lo que los autores de esta revisión mencionan los diferentes tipos de contaminantes y su mecanismo de acción sobre el aparato respiratorio, además de señalar las principales fuentes de origen y las acciones encaminadas a contrarrestar y prevenir los efectos de la contaminación atmosférica

Evaluación epidemiológica de riesgos causados por agentes químicos ambientales: Generalidades y toxicología

Contiene: Evaluación del riesgo en la exposición a sustancias tóxicas - - Identificación de las principales fuentes contaminantes del ambiente: monóxido de carbono, dióxido de azufre, oxidos de nitrógeno, hidrocarburos, lluvia ácida, bioxido de azufre, oxido de nitrógeno, ozono, monóxido de carbono - Metales: metales carcinogénicos, arsénico, cadmio, cromo, manganeso, mercurio - Plaguicidas - Toxicología