Global Impact of Sulfonamide Antibiotics on Nitrous Oxide Emissions from Aquatic Ecosystems

In this study, we combined meta-analysis, controlled incubation experiments, and quantitative global assessments to systematically evaluate the effects and underlying mechanisms of sulfonamides (SAs) on aquatic N2O emissions. Our results demonstrate that SAs strongly stimulate N2O emissions by as much as 94% at concentrations of 1–10 µg L-1, preferentially inhibiting the nosZ gene responsible for N2O consumption and thereby shifting microbial pathways toward net N2O production. At the global scale, SAs increase emissions by 73% in rivers, 62% in lakes/reservoirs, and 61% in estuarine/coastal waters, corresponding to an additional 266 Gg N2O-N yr-1. Regionally, Africa exhibits the largest increases, while recent observations indicate a rebound in coastal ecosystems.