Occurrence of Emerging Contaminants in Aquaculture Waters: Cross-Contamination between Aquaculture Systems and Surrounding Waters

This study aimed to perform a preliminary screen of various waters for pollution by emerging contaminants and identifying potential cross-contamination problems in aquaculture systems. Specifically, the occurrence and distribution of 110 emerging contaminants (49 antibiotics, 49 other pharmaceuticals, and 12 industrial/household compounds) in 14 aquaculture sites (fish, shrimp, and shellfish ponds) and three surrounding aquatic environments in Taiwan were investigated. All the detected compounds were at nanogram per liter to sub-microgram per liter levels. Six pharmaceuticals that occurred at high concentrations and frequencies were ibuprofen (788 ng/L), lincomycin (624 ng/L), flumequine (331 ng/L), caffeine (276 ng/L), ifosfamide (220 ng/L), and cephalexin (172 ng/L). Other commonly detected emerging contaminants (with detection frequencies > 70%) were sulfamethoxazole, erythromycin-H2O, atenolol, methadone, benzotriazole, tolyltriazole, perfluorobutane sulfonate (PFBS), perfluoroheptanoic acid (PFHpA), perfluorooctanoate (PFOA), and perfluorononanoic acid (PFNA). This work demonstrated the impact of aquaculture activities (i.e., usage of antibiotics) on the surrounding aquatic environments and, at the same time, how the surrounding anthropogenic activities impact aquaculture waters. Cross-contamination was observed between these two aquatic systems; emerging contaminants resulting from human activities, such as perfluorinated chemicals, anticorrosive substances, and anticancer and abused drugs, from the surrounding waters were found to be introduced into the aquaculture systems.