Santos-Medrano Gustavo Emilio, Ramírez-López Elsa Marcela, Hernández-Flores Saraí, Azuara-Medina Paulina Margarita, Rico-Martínez Roberto
Universidad Autónoma de Aguascalientes, Centro de Ciencias Básicas, Departamento de Química, Aguascalientes, Ags, C. P. 20100, Mexico.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2007 Aug;42(10):1403-10. doi: 10.1080/10934520701480557.
A quantitative study of toxicity levels of the San Pedro River and its main tributaries around the city of Aguascalientes, Mexico was conducted. Our study determined individual CL(50) values for each sampling point at 3 different times of the year corresponding to the main seasons of the year in terms of the hydrological cycle (dry, low rain and high rain season). Those LC(50) values were used to calculate the acute. Toxicity Units (aTU) that allowed us to compare levels of toxicity along the San Pedro River and two of its main tributaries. The sample that showed highest toxicity was IPIVA. This is due to the large quantity of industrial discharges that receives. Its effluent was responsible for the largest contribution of toxicity to the San Pedro River over the three rounds of sampling of this study. Our study classified an important portion of the San Pedro River and two of its main tributaries in toxic, moderately toxic and lightly toxic. No portion of the river studied was free of toxicity, either acute or sublethal. This study demonstrated that in spite of the operation of several water treatment plants along the San Pedro River, for the most part, the water quality of the river is still unacceptable.
对墨西哥阿瓜斯卡连特斯市周边圣佩德罗河及其主要支流的毒性水平进行了定量研究。我们的研究确定了一年中3个不同时间对应于水文循环主要季节（旱季、少雨季和多雨季）的每个采样点的个体半数致死浓度（CL(50)）值。这些半数致死浓度（LC(50)）值用于计算急性毒性单位（aTU），使我们能够比较圣佩德罗河及其两条主要支流沿线的毒性水平。毒性最高的样本是伊皮瓦河。这是因为它接收了大量的工业排放物。在本研究的三轮采样中，其废水对圣佩德罗河的毒性贡献最大。我们的研究将圣佩德罗河及其两条主要支流的一大部分分类为有毒、中度有毒和轻度有毒。所研究的河段没有任何部分不存在急性或亚致死毒性。这项研究表明，尽管圣佩德罗河沿线有几家水处理厂在运行，但在很大程度上，该河流水质仍然不可接受。
