Distribution of atmospheric trace elements and assesment of air quality in Argentina employing the lichen, Ramalina celastri, as a passive biomonitor: detection of air pollution emission sources

Abstract

Ramalina celastri was used as a passive biomonitor to study the relationship between elemental accumulation, emission sources and physiochemical parameters used as air pollution biomarkers in Argentina. The concentration of 27 elements was determined in the thalli by Neutron Activation Analysis (NAA). The content of photosynthetic pigments, peroxidation products, water and sulphur was determined and a Pollution Index (PI) was calculated. Factor analysis was used to locate the possible emission sources of elements. Overall, the elemental concentrations were similar to other biomonitoring studies. The higher levels of arsenic were related to the soil particulate matter, which is characteristically rich in this element. High uranium concentrations were found near a uranium mine and levated levels of zinc were found in areas congested with heavy traffic. Although there is no direct relationship found between the physiological parameters and the elemental concentrations, the geographical distribution of the PI allowed to detect areas with increased lichen damage.