title: Urinary arsenic speciation profile in ethnic group of the Atacama desert (Chile) exposed to variable arsenic levels in drinking water.
abstract: Ethnic groups from the Atacama Desert (known as Atacameños) have been exposed to natural arsenic pollution for over 5000 years. This work presents an integral study that characterizes arsenic species in water used for human consumption. It also describes the metabolism and arsenic elimination through urine in a chronically exposed population in northern Chile. In this region, water contained total arsenic concentrations up to 1250 μg L(-1), which was almost exclusively As(V). It is also important that this water was ingested directly from natural water sources without any treatment. The ingested arsenic was extensively methylated. In urine 93% of the arsenic was found as methylated arsenic species, such as monomethylarsonic acid [MMA(V)] and dimethylarsinic acid [DMA(V)]. The original ingested inorganic species [As(V)], represent less than 1% of the total urinary arsenic. Methylation activity among individuals can be assessed by measuring primary [inorganic As/methylated As] and secondary methylation [MMA/DMA] indexes. Both methylation indexes were 0.06, indicating a high biological converting capability of As(V) into MMA and then MMA into DMA, compared with the control population and other arsenic exposed populations previously reported.
authors.affiliation: a Faculty of Chemical Sciences, Department of Analytical and Inorganic Chemistry , University of Concepción , Concepción , Chile.
authors.forename: Jorge
authors.initials: J
authors.lastname: Yáñez
authors.forename: Héctor D
authors.initials: HD
authors.lastname: Mansilla
authors.forename: I Paola
authors.initials: IP
authors.lastname: Santander
authors.forename: Vladimir
authors.initials: V
authors.lastname: Fierro
authors.forename: Lorena
authors.initials: L
authors.lastname: Cornejo
authors.forename: Ramón M
authors.initials: RM
authors.lastname: Barnes
authors.forename: Dulasiri
authors.initials: D
authors.lastname: Amarasiriwardena
mesh_terms: D001151:Arsenic / Q000633:toxicity / Q000652:urine*; D001152:Arsenicals / Q000652:urine; D002101:Cacodylic Acid / Q000652:urine; D002677:Chile; D060766:Drinking Water / Q000737:chemistry* / Q000592:standards; D004784:Environmental Monitoring; D005006:Ethnicity; D006801:Humans; D008745:Methylation; D014874:Water Pollutants, Chemical / Q000633:toxicity / Q000652:urine*; D060753:Water Quality
chemical_list: D001152:Arsenicals; D060766:Drinking Water; D014874:Water Pollutants, Chemical; D002101:Cacodylic Acid; C020300:monomethylarsonic acid; D001151:Arsenic
keywords: Arsenic in urine; Atacama Desert; arsenic exposure; arsenic methylation index; arsenic speciation