Traffic related elements in tree barks and pollen abortion rates are effective to assess the effects of air pollution exposure on human health

Abstract

The majority of epidemiological studies correlate cardiorespiratory effects of air pollution exposure considering the concentration of pollutants measured from conventional monitoring networks. Conventional methodologies of air quality monitoring are expensive and have insufficient distribution for resolution in micro-scale spatial. We hypothesized that bioassays using plants could effectively determine gradients of pollutants helping to assess the associated risk of air pollution exposure. The regions of study were determined from the prevalence of cardiorespiratory deaths in Sao Paulo municipality considering different concentrations of air pollution. Samples of flower buds and barks of trees were collected in twelve sites at four districts. The genotoxic effects caused by air pollution were tested by bioassay of pollen abortion. The accumulation of elements derived from vehicular traffic in tree barks was determined using X-ray fluorescence spectrometry. Mortality data were collected from the program of mortality information. The data from elements accumulation were treated by Principal Components Analysis. Pearson correlation and exponential regression were performed considering the elements,pollen abortion rates and the mortality data. PCA analysis identified two components representing the elements related to vehicular traffic (Al, Cu, Fe, Mn, S and, Zn). These elements showed a strong correlation considering mortality (R² >0.87) and pollen abortion rates (R² >0.82). The results demonstrate that bark trees and pollen abortion allow relating vehicular traffic and associated outcomes, as genotoxic effects and mortality data.