Here, we investigated the characteristics of the environmental multimedia distribution of microcystins (MCs) introduced from freshwater discharge through the estuary dam of the Geum River. In addition, the applicability of a passive sampling device (polar organic chemical integrative sampler, POCIS) for monitoring MCs was evaluated. Surface water, suspended solids (SS), sediments, and oysters were collected from the inner and outer estuary dam. Seven MC variants were analyzed using HPLC-MS/MS. POCIS was deployed at three sites over one week, and MCs were monitored for four weeks from August to September 2019. Before POCIS was deployed in the field, compounds-specific sampling rates of MCs were determined as functions of water temperature (10, 20, and 30 °C), flow rate (0, 0.38, and 0.76 m s⁻¹), and salinity (0, 15, and 30 psu) in the laboratory. The sampling rates of MCs in POCIS increased significantly with increasing water temperature and flow rate, whereas salinity did not significantly affect the sampling rates between freshwater and saltwater. The MCs in the Geum River Estuary mainly existed as particulate forms (mean: 78%), with relatively low proportions of dissolved forms (mean: 22%), indicating that MCs were mainly contained in cyanobacterial cells. There was no significant correlation among the concentrations of MCs in water, SS, sediments, and oysters. Time-weighted average concentrations of MCs from POCIS were not significantly correlated with the concentrations of MCs in water and oysters. The metabolites of MCs, including MC-LR-GSH, MC-LR-Cys, MC-RR-GSH, and MC-RR-Cys, were detected in oysters (no metabolites were detected in POCIS). Overall, POCIS can be useful for monitoring dissolved MCs in the aquatic ecosystem, particularly in calculating time-weighted average concentrations, but it seems to have limitations in evaluating the contamination status of total MCs, mainly in particulate form.

在这里，我们研究了通过锦江河口大坝从淡水排放中引入的微囊藻毒素 (MCs) 的环境多媒体分布特征。此外，还评估了被动采样装置（极性有机化学综合采样器，POCIS）用于监测 MCs 的适用性。从内河口和外河口大坝收集地表水、悬浮固体 (SS)、沉积物和牡蛎。使用 HPLC-MS/MS 分析了七个 MC 变体。POCIS 在一周内部署在三个地点，从 2019 年 8 月到 2019 年 9 月对 MC 进行了为期 4 周的监测。和 30 °C)，流速（0、0.38 和 0.76 ms ^-1）和实验室中的盐度（0、15 和 30 psu）。POCIS 中 MCs 的采样率随着水温和流速的增加而显着增加，而盐度对淡水和咸水之间的采样率没有显着影响。锦江河口MCs主要以颗粒形式存在（平均78%），溶解形式比例较低（平均22%），表明MCs主要存在于蓝藻细胞中。水、SS、沉积物和牡蛎中MCs的浓度之间没有显着相关性。POCIS 中 MCs 的时间加权平均浓度与水和牡蛎中 MCs 的浓度没有显着相关性。MCs的代谢物，包括MC-LR-GSH、MC-LR-Cys、MC-RR-GSH和MC-RR-Cys，在牡蛎中检测到（在 POCIS 中未检测到代谢物）。总体而言，POCIS 可用于监测水生生态系统中溶解的 MC，特别是在计算时间加权平均浓度方面，但它似乎在评估总 MC 的污染状态方面存在局限性，主要是颗粒形式。