The impact of aquaculture chemotherapeutants (antibiotics, and anti-lice parasiticides) on non-target organisms is dependent on their dissipation and degradation in marine sediments. Abiotic and biotic weathering may change their composition and toxicity, and influence their fate. In this study, biodegradation of a few aquaculture chemotherapeutants was investigated over a 96 days period at 4 °C in a marine flocculent sample collected at an active site. The detected antibiotics ([sulfadiazine, amoxicillin], and one parasiticide [deltamethrin]) would have been bound to flocculent organic matter for periods exceeding a year while another anti-lice compound (emamectin benzoate) for approximately 3 months. Our results show that organic matter degradation was not accompanied by a decrease in concentrations of the antibiotics and parasiticides. This preliminary study suggests longer half-lives than documented in literature for two antibiotics and highlights the difficulty in using half-lives of chemicals determined in laboratory settings without taking into account weathering.

水产养殖化学治疗剂（抗生素和抗虱子杀寄生虫药）对非目标生物的影响取决于它们在海洋沉积物中的消散和降解。非生物和生物风化作用可能会改变其成分和毒性，并影响其命运。在这项研究中，在4°C下于活动场所收集的海洋絮凝样品中，在96天的时间内研究了几种水产化学治疗剂的生物降解。检测到的抗生素（[磺胺嘧啶，阿莫西林]和一种杀寄生虫剂[溴氰菊酯]）与絮凝性有机物的结合时间将超过一年，而另一种抗虱化合物（阿玛菌素苯甲酸酯）的结合时间约为3个月。我们的结果表明，有机物的降解并没有伴随着抗生素和杀寄生虫剂浓度的降低。