Department of Chemistry, Maseno University, P.O Box 333, 40105, Maseno, Kenya.
Bull Environ Contam Toxicol. 2012 Apr;88(4):526-32. doi: 10.1007/s00128-012-0529-7. Epub 2012 Feb 10.
Chlorpyrifos ethyl was found to be widely distributed in water and sediment in Lake Naivasha. Higher levels were reported in sediment (11.2-30.0 ng g(-1) dry weight (dw) in wet season than in dry season (4.7-17.4 ng g(-1) dw). The mean concentration of chlorpyrifos ethyl in water in wet season ranged between 8.8 and 26.6 μg L(-1) and decreased to between below detection limit to 14.0 μg L(-1) in dry season. On average, higher concentrations of chlorpyrifos ethyl were observed in sediment than water samples. Statistical analysis revealed a significant difference in concentration between the seasons, and a significant interaction between seasons and mean concentrations at p ≤ 0.05. However, levels of diazinon and carbofuran were below the detection limit in all the samples analyzed. Notably, levels of chlorpyrifos ethyl were higher than the maximum allowable limits (0.1 μg L(-1)) recommended by European Union for drinking water and general water quality criterion for protection of freshwater water organisms (0.083 μg L(-1)).
乙基毒死蜱在奈瓦沙湖的水和沉积物中被广泛发现。据报道，在雨季，沉积物中的含量更高（湿季为 11.2-30.0ng/g 干重，干季为 4.7-17.4ng/g 干重）。雨季水中乙基毒死蜱的平均浓度在 8.8 和 26.6μg/L 之间，而在旱季则降至检测限以下至 14.0μg/L。平均而言，沉积物中的乙基毒死蜱浓度高于水样。统计分析显示，浓度在季节之间存在显著差异，在季节和平均浓度之间存在显著交互作用，p 值≤0.05。然而，在所有分析的样本中，二嗪磷和克百威的浓度均低于检测限。值得注意的是，乙基毒死蜱的浓度高于欧盟推荐的饮用水最大允许限量（0.1μg/L）和保护淡水生物的一般水质标准（0.083μg/L）。
