Biomonitoramento dos efeitos genotóxicos relacionados à poluição atmosférica em ambientes de intenso tráfego de veículos: Contribuições para a vigilância em saúde ambiental de populações expostas

Abstract

A biological assessment of environmental quality was performed using the tropical plant species Tradescantia pallida (Rose) D.R. Hunt. var. purpurea exposed to different levels of air contamination in urban intersections with high volume of vehicle traffic. Air quality (average daily levels of particulate material in the PM1, 2.5, 10 fractions) and traffic volume in crossing intersections were monitored for 30 days before the collection of plants. Frequency of micronuclei and pollen abortivity in inflorescences collected at different intersections with gradual levels of traffic volume were evaluated as biomarkers of genotoxicity. In addition, the concentrations of bioaccumulated heavy metals in the leaves of the collected plants were also investigated. The proposed biological assessment model found a positive association between the environmental variables (traffic volume; concentration of particulate material) and biological effects (leaf concentration of Cr and Cd; micronucleus frequencies and pollen abortivity).

Atmospheric pollution is generally monitored through physicochemical indicator systems. Variations of these indicators in relation to environmental legislation parameters report on air quality, especially in large cities. However, the interpretation of environmental data on pollutants needs to be complemented, as the impacts of pollution on sensitive organisms serve as a warning to public health authorities. The use of species adapted to the urban environment as sentinels enables continuous and integrated monitoring of the effects of environmental pollution on biological systems. In this study, we used the tropical plant species Tradescantia pallida, planted in ornamental beds at the main urban intersections in the city of Uberlândia, Brazil, to monitor the genotoxic effects of atmospheric pollution under different vehicular traffic conditions. In four samples, we compared biological, physical-chemical and traffic indicators at different intersections (in residential and commercial areas) during the period of restriction of local commerce activities, imposed by health agencies, as a measure to face the COVID-19 pandemic. With the decrease in vehicle traffic due to the lockdown, it was found that this species is sensitive to environmental changes of pollutants in the air and soil. T. pallida bioaccumulated heavy metals under conditions of exposure to greater vehicular traffic, where higher concentrations of these contaminants were also found in the soil. Furthermore, from the Micronucleus Test, we found that genotoxicity can be estimated from a multiple linear regression model, including (X1) chromium concentration in the soil and (X2) particulate matter in the atmosphere as the main independent variables. Our findings are important contributions to the (re)definition of parameters and models of Environmental Health Surveillance.