Seasonal Variation and Land-use Effects On Heavy and Emerging Metallic Contaminants In The Atmosphere Of Central And Northern Regions of Argentina

LIDWINA BERTRAND; GABRIELA CALDERON; MAGDALENA VICTORIA MONFERRAN; JOCHEN F. MULLER; XIANYU WANG

Montevideo

Congreso; SETAC Latin America 15th Biennial Meeting; 2023

SETAC Latin America

According to the World Health Organization, air pollution is responsible for causing one million deaths annually. Additionally, the surrounding land use has been identified as a potential source of trace metals released into the atmosphere. The objective of this study was to assess the seasonal variation of atmospheric metallic contaminants (MC) in areas of Argentina with different land uses. Furthermore, an enrichment factor (EF) was calculated to estimate the anthropogenic contribution to atmospheric MC. To achieve this, polyurethane foam disk (PUF) passive air samplers were deployed seasonally over the course of one year in five different locations: Miramar (MIR), Río Tercero (RT), Almafuerte (ALM), Tucumán (TUC), and Catamarca (CAT). Subsequently, fractions of collected PUF disk were digested for quantification of heavy (Al, Cr, Cu, Pb) and emerging (Y,Ti, Nb) MC (ICP-MS analysis). Land Use and Land Cover classification in the surrounding areas of each site (3km radius) was determined using satellite imagery (QGIS 3.22). EF values >10 were considered indicative of a significant anthropogenic contribution. Our results show seasonal variations in most of the analyzed elements and sites. During the winter season, CAT, MIR, and TUC sites exhibited higher uptake of MC, which is consistent with the windier conditions during that time. Conversely, ALM site showed increased uptake during the summer season, while no clear seasonal pattern was observed at the RT site. Among the sites, the CAT site showed the highest uptake for Pb, Cr, Ti, Cu, and Nb, whereas the ALM site exhibited higher uptake for Al and Y. In terms of EF, a significant anthropogenic contribution was observed for Cu in the TUC site and for Pb across all sites,particularly in CAT, TUC, and RT. During the spring season, the TUC site exhibited an EF close to 10 for Cr, suggesting a potential anthropogenic contribution. The EF for Ti and Nb did not indicate anthropogenic contributions. The principal component analysis explained 64% of the variability through the first two components. RT and TUC sites were clearly associated with industrial and residential land uses. Agriculture predominated in the ALM site, which was associated with Y and Al levels. Finally, the CAT site, despite its predominant forest land use, was associated with atmospheric Pb. Given the prevailing northerly winds at this site, our results suggest a significant contribution of regional mining activity to the air quality at CAT.