ABSTRACT

Background and Objectives: One major source of antibiotic contamination in the sea is from aquaculture. We monitored the concentration of commonly used antibiotic classes and antibiotic resistance genes (tet(M), sul1, sul2 and sul3) in aquaculture farms in Peninsular Malaysia.

Methods: Antibiotic residues and resistance genes were quantified using high-performance liquid chromatography and real-time PCR respectively. Risk quotients in European technical guidance document on risk assessment was used to assess the potential environmental risk.

Results: We detected 23 antibiotics with tetracyclines, sulfonamides and quinolones were the most frequently detected classes, indicating a wide distribution of antibiotics in Malaysian aquaculture farms. The dendrogram and heatmap revealed three groups of antibiotic concentration patterns but with no differences in the types of antibiotics usage among aquaculture farms. The ARGs (10⁻³ copies/16S) were detected in >90% of the sites except for sul3. Ciprofloxacin, enrofloxacin, norfloxacin and lincomycin posed risks to cyanobacteria and algae in Kelantan, Perak and Pahang.

Conclusion: Relative to Asian aquaculture farms, the residues detected here were at low or moderate levels except for quinolones. This study will be useful to develop effective management of aquaculture wastewater in order to mitigate antibiotic pollution and transmission of ARGs to humans through the food chain.

摘要

背景和目的：海洋中抗生素污染的主要来源之一是水产养殖。我们监测了马来西亚半岛水产养殖场中常用抗生素类别和抗生素抗性基因（tet (M)、sul1、sul2和sul3）的浓度。

方法：分别采用高效液相色谱法和实时荧光定量 PCR 对抗生素残留和耐药基因进行定量。欧洲风险评估技术指导文件中的风险商数用于评估潜在的环境风险。

结果：我们检测到 23 种抗生素，其中四环素类、磺胺类和喹诺酮类是最常检测到的类别，表明马来西亚水产养殖场中抗生素分布广泛。树状图和热图揭示了三组抗生素浓度模式，但水产养殖场之间抗生素使用类型没有差异。在除sul3之外的 >90% 的位点中检测到ARG（10 ^-3拷贝/16S）。环丙沙星、恩诺沙星、诺氟沙星和林可霉素对吉兰丹、霹雳和彭亨的蓝藻和藻类构成风险。

结论：相对于亚洲水产养殖场，除喹诺酮类药物外，这里检测到的残留量处于低或中等水平。这项研究将有助于对水产养殖废水进行有效管理，以减轻抗生素污染和 ARG 通过食物链向人类的传播。