Occurrence of veterinary drug residues in farmed fishery products in South Korea

- We investigated veterinary drug residues in 958 fish samples from Korea.
- Enrofloxacin and oxytetracycline were commonly detected in fishery products.
- Twelve of 958 samples (1.3%) exceeded the maximum residue limit set by Korea.
- The detection rate in freshwater fish was higher than that in seawater fish.
- Various residues of veterinary drugs were often detected in combination.

Residues of veterinary drugs were investigated in fish samples from domestic farms in South Korea to highlight the changing trends in drug usage during aquatic food production. Samples (n = 958) were collected from 32 cities and 11 provinces. In total, 41 veterinary drugs were analyzed using an LC-MS/MS. The total detection rate of veterinary drugs in fish samples was 22.7% (n = 217). Enrofloxacin and oxytetracycline were mostly detected in fishery products. Moreover, 12 samples (1.3%) exceeded the maximum residue limit set by Korea. The detection rate for veterinary drug residues varied with fish species and water type. Additionally, our findings show that of the two or more residues in 87 samples, enrofloxacin was often detected in combination with ciprofloxacin, and other compound. Our results of this study suggested the need for an appropriate withdrawal period of fishery products are required to guarantee safe residue levels.