Hazard quotient

Trimethoprim

Wastewater

Sediment

Biology

Tributary

Animal science

Cartography

Sulfadiazine

Sulfamethoxazole

Paleontology

Environmental engineering

Surface water

Geography

Toxicology

Environmental chemistry

Antibiotics

Agronomy

Microbiology

Environmental science

Heavy metals

Oxytetracycline

Chemistry

Dry weight

Ecotoxicology and Environmental Safety

Thirteen antibiotics including sulfonamides (SAs), tetracyclines (TETs) and fluoroquinolones (FQs) were measured in Hanjiang River (HR) during two periods. The total concentrations of 13 antibiotics in surface water and sediments ranged from 3.1 to 109 ng/l and from 10 to 45 ng/g dry weight, respectively. SAs were dominant in water while the concentrations of TETs were the highest in sediments in two seasons. For their spatial distribution, total concentrations of 13 antibiotics in both matrices were significantly higher in the lower section of HR (p < 0.02, F > 5.15) due to wastewater release, agricultural activities and water transfer project. Obvious seasonal variations of sulfadiazine, sulfameter, trimethoprim and oxytetracycline in water were observed (p < 0.05, F > 4.62). Phase partition of antibiotics between water and sediments suggested a greater affinity of TETs and FQs to sediments. In addition, significantly positive relationships were found between SAs (sulfameter, sulfamethoxazole and trimethoprim) and sediment TOC (p < 0.05). Risk assessment indicated that the hazard quotients of antibiotics were higher in the sediment than those in the water. Moreover, antibiotic mixtures posed higher ecological risks to aquatic organisms.

Antibiotics in surface water and sediments from Hanjiang River, Central China: Occurrence, behavior and risk assessment