title: Arsenic exposure of rural populations from the Rift Valley of Ethiopia as monitored by keratin in toenails.
abstract: Arsenic (As) contamination of drinking water is a worldwide phenomenon whose effect among vulnerable and rural communities in the Rift Valley of Ethiopia in eastern Africa is not well studied. This study examines As exposure and bioaccumulation from drinking water by monitoring human keratin in the form of toenails from exposed populations. Groundwater samples from drinking water wells (n=34) were collected along with toenail samples (n=58) from local communities and were analyzed for trace metals including As by inductively coupled plasma mass spectrometry (ICP-MS). Of the total number of wells tested, 53% had As level above the WHO maximum contamination level of 10 p.p.b. Arsenic in toenails was significantly correlated to corresponding drinking water (r=0.72; R(2)=0.52; P<0.001). This correlation improves for drinking water with As concentrations above 2 p.p.b. (r=0.74; R(2)=0.54; P<0.001). Male minors (<18 years old) were found to have greater nail-As concentrations compared with adults consuming equal amounts of As (P<0.05). Estimated As dose specifically from drinking water sources was also associated with nail concentrations (P<0.01). We suggest that As measurement in nails could be a reliable method for detecting As exposure in residents living in rural areas.
authors.affiliation: Division of Earth and Ocean Sciences, Nicholas School of the Environment, Duke University, Durham, North Carolina, USA.
authors.forename: R Brittany
authors.initials: RB
authors.lastname: Merola
authors.affiliation: Duke Clinical Research Institute, Duke University Medical Center, Durham, North Carolina, USA.
authors.forename: Julia
authors.initials: J
authors.lastname: Kravchenko
authors.affiliation: Division of Earth and Ocean Sciences, Nicholas School of the Environment, Duke University, Durham, North Carolina, USA.
authors.forename: Tewodros
authors.initials: T
authors.lastname: Rango
authors.affiliation: Division of Earth and Ocean Sciences, Nicholas School of the Environment, Duke University, Durham, North Carolina, USA.
authors.forename: Avner
authors.initials: A
authors.lastname: Vengosh
mesh_terms: D001152:Arsenicals / Q000032:analysis*; D060766:Drinking Water / Q000737:chemistry*; D004781:Environmental Exposure; D005002:Ethiopia; D006801:Humans; D007633:Keratins / Q000032:analysis*; D013058:Mass Spectrometry; D009262:Nails / Q000737:chemistry*; D012424:Rural Population; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000633:toxicity
chemical_list: D001152:Arsenicals; D060766:Drinking Water; D014874:Water Pollutants, Chemical; D007633:Keratins