title: Implementing Lecane quadridentata acute toxicity tests to assess the toxic effects of selected metals (Al, Fe and Zn).
abstract: An environmental study revealed that three metals (Al, Fe and Zn) are common in the San Pedro River (SPR) (Aguascalientes, Mexico). Regrettably, in many samples the concentrations of these metals exceeded the maximum allowed toxicant concentrations levels as defined in by Mexican legislation. The highest concentrations of the three metals were found during the 2005 dry season, with elevated Al concentrations present along the entire river. Not surprisingly, the highest concentrations for all three metals came from locations adjacent to industrial areas. Estimates of the contribution of these metals to total toxicity revealed that these three metals are important contaminants of the river and responsible for most of the lethal toxicity found in environmental samples. To assess the importance of these reports, we conducted acute toxicity tests to determine LC50 for Al, Fe and Zn on the freshwater rotifer Lecane quadridentata. This permitted us to estimate the contribution of these metals to total toxicity during 2005-2006. Based on LC50 values, all three metals should be considered very toxic, with the zinc LC50 value (0.12 mg L(-1)) making it the most toxic metal for L. quadridentata. This approach can be applied to other sites with similar concentrations of these metals.
authors.affiliation: Universidad Autónoma de Guerrero, Departamento de Química, Avenida Lázaro Cárdenas s/n, ciudad universitaria, Chilpancingo 39660, Gro. México. torresfelix2000@yahoo.com.mx
authors.forename: Félix Torres
authors.initials: FT
authors.lastname: Guzmán
authors.forename: Francisco Javier Avelar
authors.initials: FJ
authors.lastname: González
authors.forename: Roberto Rico
authors.initials: RR
authors.lastname: Martínez
mesh_terms: D000535:Aluminum / Q000032:analysis / Q000633:toxicity*; D000818:Animals; D004784:Environmental Monitoring; D007501:Iron / Q000032:analysis / Q000633:toxicity*; D007928:Lethal Dose 50; D008800:Mexico; D045483:Rivers / Q000737:chemistry; D012403:Rotifera / Q000187:drug effects*; D012621:Seasons; D023382:Toxicity Tests, Acute; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D014887:Weather; D015032:Zinc / Q000032:analysis / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical; D000535:Aluminum; D007501:Iron; D015032:Zinc