RESUMO
For regulatory purposes, air pollution has been reduced to management of air quality control regions (AQCR), by inventorying pollution sources and identifying the receptors significantly affected. However, beyond being source-dependent, particulate matter can be physically and chemically altered by factors and elements of climate during transport, as they act as local environmental constraints, indirectly modulating the adverse effects of particles on the environment and human health. This case study, at an industrial site in a Brazilian coastal city - Joinville, combines different methodologies to integrate atmospheric dynamics in a strategic risk assessment approach whereby the influence of different wind regimes on environmental and health risks of exposure to PM2.5-bound elements, are analysed. Although Joinville AQCR has been prone to stagnation/recirculation events, distinctly different horizontal wind circulation patterns indicate two airsheds within the region. The two sampling sites mirrored these two conditions and as a result we report different PM2.5 mass concentrations, chemical profiles, geo-accumulation, and ecological and human health risks. In addition, feedback mechanisms between the airsheds seem to aggravate the air quality and its effects even under good ventilation conditions. Recognizably, the risks associated with Co, Pb, Cu, Ni, Mn, and Zn loadings were extremely high for the environment as well as being the main contributors to elevated non-carcinogenic risks. Meanwhile, higher carcinogenic risks occurred during stagnation/recirculation conditions, with Cr as the major threat. These results highlight the importance of integrating local airshed characteristics into the risk assessment of PM2.5-bound elements since they can aggravate air pollution leading to different risks at a granular scale. This new approach to risk assessment can be employed in any city's longer-term development plan since it provides public authorities with a strategic perspective on incorporating environmental constraints into urban growth planning and development zoning regulations.
RESUMO
This study applied two data mining tasks: clustering and association rules to a dataset of pollutants in the state of São Paulo. The clustering task was applied to temporal patterns and geospatial distributions of pollutants, and the association rules were used to identify prevailing meteorological conditions when there were high concentrations of pollutants from 2017 to 2019. The results indicated good adequacy of the cluster, indicating different pollution levels per group, with a silhouette coefficient from 0.26 to 0.72. In the spatial evaluation, the groups severely polluted were located in the metropolitan region, on the coast and, some inland cities, by industrial, vehicular, burning, agriculture, and other emissions. The cluster identified a strong presence of O3 and PM2.5 in 65% and 72% of the monitored stations in several areas of the state. As for the distance between the sources of pollution, the groups of PM10 and NO2 were geographically distant, while PM2.5, CO, SO2, and O3 were closer, suggesting a spatial relationship of exposure. Seasonality was similar between groups, with significantly higher concentrations in winter, except for O3, for which higher concentrations occurred in summer. Meteorological conditions contributed to critical episodes of pollution (support and confidence greater than 80%), with low temperature and humidity, low rainfall, and milder wind associated with increased pollutants. In conclusion, investigating spatial representativeness allows revealing spatial and temporal patterns of pollutants and unfavorable meteorological conditions to diffusion. Thus, ideal and effective measures can be taken to avoid critical periods of exposure based on the behavior of pollutants in different regions and related climate changes.
Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Brasil , China , Cidades , Monitoramento Ambiental/métodos , Dióxido de Nitrogênio/análise , Material Particulado/análiseRESUMO
RESUMO O agravamento da poluição atmosférica nos centros urbanos devido ao crescimento das instalações industriais e da frota veicular é um problema que causa danos ambientais, afetando também a saúde humana, principalmente pela inalação de material particulado fino (MP2,5). O objetivo deste estudo foi avaliar a influência das condições meteorológicas na concentração de MP2,5 em Belo Horizonte, utilizando dados amostrados entre o inverno de 2007 e o outono de 2008. Além disso, foram avaliadas as diferenças dos dados meteorológicos e da concentração do MP2,5 entre as estações do ano nesse período. Para tanto, foram realizados testes estatísticos de correlação entre os dados meteorológicos e a concentração de MP2,5, além de análises de significância para avaliação das diferenças entre esses dois parâmetros nos períodos seco e chuvoso, característicos da área de estudo. Foi observada diferença significativa entre a concentração do MP2,5 nos períodos seco e chuvoso. Foram também observadas diferenças significativas entre os parâmetros meteorológicos (umidade relativa; temperatura mínima, média e máxima; e direção do vento) para esses períodos. Por meio da análise de correlação de Spearman, observou-se correlação significativa entre a concentração do MP2,5 e os parâmetros meteorológicos precipitação e umidade relativa do ar.
ABSTRACT The increase of air pollution in urban centres due to the growth of industrial facilities and vehicular fleet is a problem that causes environmental damage and affects human health, mainly due to the inhalation of fine particulate matter (PM2.5). For this reason, the aim of this study was to evaluate the influence of meteorological conditions on PM2.5 concentration in Belo Horizonte, using data sampled from the winter of 2007 to the autumn of 2008. In addition, the differences in meteorological data and PM2.5 concentration between the seasons of the year in this study's period were also assessed. For this, correlation statistical tests were performed for meteorological data and PM2.5 concentration, as well as significance analysis to evaluate the differences between these two parameters in the dry and wet periods, characteristic of the study area. It was observed a significant difference between PM2.5 concentration in dry and wet periods. Significant differences were also observed between meteorological parameters (relative humidity, minimum, mean and maximum temperature and wind direction) for these periods. Spearman's correlation analysis showed a significant correlation between PM2.5 concentration and the meteorological parameters precipitation and relative humidity.