尽管在农业中广泛使用了球球藻素杀菌剂(SFs),对它们在水生生态系统中的分布和生物积累知之甚少。在这项研究中,在非生物(水和沉积物;n=83)和生物(植物,藻类,浮游动物,和鱼类;n=123)从亚热带淡水生态系统中收集的样本,即,东江湿地,在中国南方。在测量的12个SFs中,在地表水(中位数:2.20ng/L)和沉积物(0.064ng/g干重。).偶氮酯酸(AZ-酸),AZ的代谢产物,是植物样品中的主要分析物并且具有0.36ng/g干重的中值浓度。在藻类和浮游动物中,(Z)-美托霉素是主要的杀真菌剂,中值浓度为3.52和5.55ng/g干重。,分别。在鱼的肌肉中,dimoxstrobin(DIMO)是主要的SF,中位浓度为0.47ng/g干重。AZ-酸的生物富集因子(BCF)值,trifloxystrobin(TFS),藻类和浮游动物和AZ-酸,PYR,TFS,TFS酸,picoxystrobin,鱼肌肉中的DIMO超过1000L/kg(藻类,浮游动物,和鱼的浓度以干重为基础表示),这表明这些杀菌剂可以在生物群中积累。观察到鱼中SF的logBCFs与SF的logKow之间呈正相关,而logBCFs与log溶解度指数之间呈负相关。此外,计算风险商(RQ)以评估SFs对不同水生生物(藻类,浮游动物,和鱼)。19个采样点的PYR和DIMO浓度的RQ值>0.1,表明对水生生物的生态毒理学风险中等。这项研究首次记录了SFs及其代谢物在水生生态系统中的广泛存在,并阐明了SFs在水生生物中的生物积累潜力。
Despite the widespread application of strobilurin fungicides (SFs) in agriculture, little is known about their distribution and bioaccumulation in aquatic ecosystems. In this study, the concentrations of 12 SFs and two of their metabolites were determined in abiotic (water and sediment; n = 83) and biotic (plant, algae, zooplankton, and fish; n = 123) samples collected from a subtropical freshwater ecosystem, namely, Dongjiang River wetland, in southern China. Among the 12 SFs measured, azoxystrobin (AZ) was the major fungicide found in surface water (median: 2.20 ng/L) and sediment (0.064 ng/g dry wt.). Azoxystrobin acid (AZ-acid), a metabolite of AZ, was the major analyte in the plant samples and had a median concentration at 0.36 ng/g dry wt. In algae and zooplankton, (Z)-metominostrobin was the predominant fungicide and had median concentrations of 3.52 and 5.55 ng/g dry wt., respectively. In fish muscle, dimoxystrobin (DIMO) was the major SF and had a median concentration of 0.47 ng/g dry wt. The bioconcentration factor (BCF) values of AZ-acid, trifloxystrobin (TFS), and pyraclostrobin (PYR) in algae and zooplankton and AZ-acid, PYR, TFS, TFS-acid, picoxystrobin, and DIMO in fish muscle exceeded 1000 L/kg (algae, zooplankton, and fish concentrations were expressed on a dry weight basis), suggesting that these fungicides can accumulate in biota. A positive association between log BCFs of SFs in fish and logKow of SFs and a negative correlation between log BCFs and the log solubility index were observed. Additionally, the risk quotient (RQ) was calculated to evaluate the potential ecotoxicological risk of SFs to different aquatic organisms (algae, zooplankton, and fish). The PYR and DIMO concentrations at 19 sampling sites had RQ values >0.1, indicating moderate ecotoxicological risks to aquatic organisms. This study is the first to document the widespread occurrence of SFs and their metabolites in aquatic ecosystems and to elucidate the bioaccumulation potential of SFs in aquatic organisms.