Bench‐scale trials were performed to (1) expose Microcystis aeruginosa cells to potassium permanganate (KMnO₄) doses of 1, 3, and 5 mg/L at contact times (CTs) of 15, 30, and 90 min, pH levels of 7 and 9, and turbidities of 0.1, 5, and 20 ntu, respectively; (2) compare the impacts of oxidation alone and oxidation plus powdered activated carbon (PAC) for the final 60 min of CT; and (3) evaluate the impact of these treatment conditions on extracellular microcystins (MCs), extra‐plus intracellular (combined) MCs, cell membrane integrity, and chlorophyll a concentrations. Toxin releases from the cells were observed at both pH levels. The greatest toxin releases were observed at the lowest KMnO₄ doses. The toxin releases were accompanied by relatively stable total cell counts, increases in membrane‐compromised cells, and decreases in chlorophyll a. The application of 10 mg/L PAC resulted in extracellular toxin concentrations that were markedly lower than those observed in oxidant‐only situations.

中文翻译：

---

高锰酸钾和粉末状活性炭对氰毒素释放的影响。

进行了基准试验，以（1）在15、30和90分钟的接触时间（CT）下，将铜绿微囊藻细胞暴露于1、3和5 mg / L的高锰酸钾（KMnO ₄）剂量下。 7和9，浊度分别为0.1、5和20 ntu；（2）比较CT的最后60分钟单独氧化和氧化加粉状活性炭（PAC）的影响；（3）评估这些治疗条件对细胞外微囊藻毒素（MCs），细胞外（组合）MCs，细胞膜完整性和叶绿素a浓度的影响。在两个pH水平下均观察到细胞中毒素的释放。在最低的KMnO _4下观察到最大的毒素释放剂量。毒素释放伴随着相对稳定的总细胞计数，膜受损细胞增加，而叶绿素a减少。10 mg / L PAC的使用导致细胞外毒素的浓度明显低于仅氧化剂的情况。