Ethiopian Institute of Water Resources, Addis Ababa University, P. O. Box 1176, Addis Ababa, Ethiopia.
Department of Zoological Sciences, Addis Ababa University, P. O. Box 1176, Addis Ababa, Ethiopia.
Toxicon. 2019 Oct;168:83-92. doi: 10.1016/j.toxicon.2019.06.217. Epub 2019 Jun 20.
This study was carried out with a view of understanding the temporal dynamics of microcystin concentrations in both algal seston and water samples and the associated public health risk. All the major MC variants, namely MC-LR, MC-YR, and MC-RR, were detected in both the algal seston and water samples. In the majority of the samples, the most potent variant, MC-LR, constituted the greatest proportion of the total MC concentration suggesting extremely high potential public health risk. The exceptionally high concentrations (μg L) of all the variants, MC-LR (815), MC-YR (466.6) and MC-RR (265.68), were observed in May. Although the extracellular MCs were relatively less concentrated and less frequently detected, concentrations (μg L) of up to 20 of MC-LR, 6.13 of MC-YR, and 1.27 MC-RR were encountered. The strong and significant association between Microcystis abundance and concentration of nitrate (Spearman Rank Order Correlation r = 0.793, p < 0.001) may suggest that nitrate is the key dictating factor in the dynamics of Microcystis, and may have consequently influenced the MC levels in the reservoir.
本研究旨在了解藻类悬浮物和水样中微囊藻毒素浓度的时间动态变化及其相关的公共健康风险。在藻类悬浮物和水样中均检测到所有主要的 MC 变体，即 MC-LR、MC-YR 和 MC-RR。在大多数样本中，最具毒性的变体 MC-LR 构成了总 MC 浓度的最大比例，表明存在极高的公共健康风险。所有变体（MC-LR[815]、MC-YR[466.6]和 MC-RR[265.68]）的浓度（μg/L）在 5 月特别高。尽管细胞外 MC 的浓度相对较低且检测频率较低，但仍遇到了高达 20 μg/L 的 MC-LR、6.13 μg/L 的 MC-YR 和 1.27 μg/L 的 MC-RR。微囊藻丰度与硝酸盐浓度之间存在强烈而显著的关联（Spearman 秩相关系数 r=0.793，p<0.001），这可能表明硝酸盐是微囊藻动态变化的关键决定因素，并可能因此影响了水库中的 MC 水平。
