Future trends in antibiotic concentrations and risk assessment of selection pressure based on reported antibiotic concentrations in Brazil's aquatic environments

Antibiotic resistance (AMR) in aquatic environments poses a significant threat to public and environmental health. In this study, antibiotic compounds were used to estimate selection pressure and associated risks using the risk quotient (RQ) methodology. Future antibiotic concentrations were projected through a polynomial regression model based on compiled data from studies on antibiotic levels in Brazilian water bodies, covering the period from 2012 to 2030. The reviewed studies revealed heterogeneity in the types of antibiotics detected, with substantial geographic variation. Overall, ciprofloxacin concentrations detected in different regions of Brazil were classified as medium to high risk, with urbanized areas presenting the highest risks. The North and Northeast regions were underrepresented, limiting the applicability of the conclusions at a national level. Furthermore, the temporal analysis of antibiotic concentrations between 2012 and 2026 indicates a decline from 2012 to 2014, followed by significant recovery and increase until 2018, with stabilization and projected growth until 2030. These findings emphasize the urgent need for national regulations and the incorporation of environmental monitoring, with standardized data collection protocols, into the public health surveillance system to control and mitigate the risks associated with AMR in Brazil.