Antibiotics in the aquatic environment. A deep voyage across chemical occurrence data, socio-economic relationships and international policies on antimicrobial consumption and resistance within 2014–2024

Despite the outstanding efforts of the international organizations in implementing global policies, the upward trend of antimicrobial consumption (AMC) and antimicrobial resistance (AMR) in the last biennium, after a slight decline throughout the last decade, has been resonating like a warning worldwide. Furthermore, the impact of emerging contaminants including antibiotics in the environment should not be underestimated, since they contribute to antibiotic-resistant mechanisms. Their aquatic environment occurrence, often resulting from misuse and incapability of wastewater treatment plants (WWTPs)-where available-to completely remove these compounds could pose a risk to living organisms. Built on a One Health-basis and aimed at serving as reference point for scientists to cover the gaps of chemical occurrence data and to address future researches on less studied sites, this review has examined 6305 occurrence concentration data for 142 antibiotics (including transformation products and metabolites) across 76 countries and 6 continents during 2014-2024 in groundwater and surface water. Data distribution was different being surface water 7 times more represented than groundwater, while Europe and Asia the continents with the highest publication rates. Sulfonamides were the most investigated unlike carbapenems and polymyxins. Low- and Middle- Income Countries (LMICs) reported the highest cumulative concentrations peaking at 781.98 ng/L, while trace levels in Antarctica, rich in migratory phenomena, have risen scientific interests in understanding early-stage zoonotic interactions. Antibiotic occurrence also depends on the fate and degradation mechanisms in the aquatic media, but degradation products are rarely studied. Considering that their toxicity is yet to be evaluated, analytical efforts are recommended in the farsighted perspective to perform a comprehensive environmental risk assessment of these emerging contaminants at the earliest.