Elevated water temperature reduces the acute toxicity of the widely used herbicide diuron to a green alga, Pseudokirchneriella subcapitata
Elevated water temperature reduces the acute toxicity of the widely used herbicide diuron to a green alga, Pseudokirchneriella subcapitata
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DOI：
10.1007/s11356-013-1989-y
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发表时间：
2014-01-01
影响因子：
5.8
通讯作者：
Oshima, Yuji
中科院分区：
文献类型：
--
作者：
Tasmin, Rumana;Shimasaki, Yohei;Oshima, Yuji
在实际环境中，温度随季节或全球变暖而剧烈波动，被认为会影响水生生物群的污染物风险；然而，水温对广泛使用的除草剂迪乌隆对淡水微藻毒性的影响尚未见报道。本研究研究了在5种不同温度（10、15、20、25和30℃）下，diuron对绿藻类Pseudokirchneriella subcapitata生长和光合活性的抑制作用。结果,有效敌草隆发生藻类增长减少50%浓度增加而增加水温度范围从9.2到20.1μg 72 h l - 1和9.4 - -28.5μg l - 1 h。144的光化学效率光系统II (F (v) / F (m)比率)被敌草隆在所有温度下显著降低暴露在32 72 h后μg l - 1。抑制率显著增加了水温下降(P < 0.01)。作为氧化应激指标的细胞内H2O2水平随温度升高而降低，diuron处理组比对照组高约2.5倍（P < 0.01）。我们的研究结果表明水温可能会影响淡水中diuron的毒性动力学，因此应在环境风险评估中予以考虑。
In the actual environment, temperatures fluctuate drastically through season or global warming and are thought to affects risk of pollutants for aquatic biota; however, there is no report about the effect of water temperature on toxicity of widely used herbicide diuron to fresh water microalgae. The present research investigated inhibitory effect of diuron on growth and photosynthetic activity of a green alga Pseudokirchneriella subcapitata at five different temperatures (10, 15, 20, 25, and 30 A degrees C) for 144 h of exposure. As a result, effective diuron concentrations at which a 50 % decrease in algal growth occurred was increased with increasing water temperature ranging from 9.2 to 20.1 mu g L-1 for 72 h and 9.4-28.5 mu g L-1 for 144 h. The photochemical efficiency of photosystem II (F (v)/F (m) ratio) was significantly reduced at all temperatures by diuron exposure at 32 mu g L-1 after 72 h. Inhibition rates was significantly increased with decreased water temperature (P < 0.01). Intracellular H2O2 levels as an indicator of oxidative stress were also decreased with increasing temperature in both control and diuron treatment groups and were about 2.5 times higher in diuron treatment groups than that of controls (P < 0.01). Our results suggest water temperatures may affect the toxicokinetics of diuron in freshwater and should therefore be considered in environmental risk assessment.