Concentrations of potentially toxic metals in urban streams of Santo André municipality (SP, Brazil)
The environment provides various essential services to human life, known as ecosystem services, which allow for a better understanding of the strong connection between nature and society. Water ecosystem services are directly related to the quality and quantity of water, which, in turn, depends on the type, land use configuration, and land occupancy. This study analyzed water quality in seven microbasins in the Santo André region of São Paulo, Brazil, and correlated it with seasonality, the percentage of green areas, and the percentage of industrial areas. Samples were collected during both dry and rainy periods, and metal concentrations were analyzed using ICP-MS spectrophotometry. The results were examined using the Past software, applying Kruskall-Wallis, Mann-Whitney, and Principal Component Analysis. The findings indicated a stronger correlation between metals and dry periods, suggesting that rain can dilute these metals. Green areas were more closely associated with metal concentrations, while industrial areas were more closely related to dissolved oxygen levels. The analyzed region is heavily urbanized, with less than 5% of the studied sub-basins consisting of green areas. It is suggested that the limited extent of green areas may be insufficient to have a significant impact in a region with numerous sources of pollution.