title: Spatial and temporal variability of fluoride concentrations in groundwater resources of Larestan and Gerash regions in Iran from 2003 to 2010.
abstract: There is discrepancy about intervals of fluoride monitoring in groundwater resources by Iranian authorities. Spatial and temporal variability of fluoride in groundwater resources of Larestan and Gerash regions in Iran were analyzed from 2003 to 2010 using a geospatial information system and the Mann-Kendall trend test. The mean concentrations of fluoride for the 8-year period in the eight cities and 31 villages were 1.6 and 2.0 mg/l, respectively; the maximum values were 2.4 and 3.8 mg/l, respectively. Spatial, temporal, and spatiotemporal variability of fluoride in overall groundwater resources were relatively constant over the years. However, results of the Mann-Kendall trend test revealed a monotonic trend in the time series of one city and 11 villages for the 8-year period. Specifically, one city and three villages showed positive significant Kendall's Tau values, suggesting an upward trend in fluoride concentrations over the 8-year period. In contrast, seven villages displayed negative significant Kendall's Tau values, arguing for a downward trend in fluoride concentrations over the years. From 2003 to 2010, approximately 52 % of the Larestan and Gerash areas have had fluoride concentrations above the maximum permissible Iranian drinking water standard fluoride level (1.4 mg/l), and about 116,000 people were exposed to such excess amounts. Therefore, our study supports for a close monitoring of fluoride concentrations from health authorities in monthly intervals, especially in villages and cities that showed positive trend in fluoride concentrations. Moreover, we recommend simultaneous implementation of cost-effective protective measures or interventions until a standard fluoride level is achieved.
authors.affiliation: Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute (Swiss TPH), Socinstrasse 57, 4002, Basel, Switzerland. hassan.amini@unibas.ch.|University of Basel, Petersplatz 1, 4003, Basel, Switzerland. hassan.amini@unibas.ch.|Kurdistan Environmental Health Research Center, Kurdistan University of Medical Sciences, Sanandaj, Iran. hassan.amini@unibas.ch.
authors.forename: Hassan
authors.initials: H
authors.lastname: Amini
authors.affiliation: Larestan School of Medical Sciences, Larestan, Iran. gholamali.haghighat@yahoo.com.|University of Applied Science and Technology, Larestan, Iran. gholamali.haghighat@yahoo.com.
authors.forename: Gholam Ali
authors.initials: GA
authors.lastname: Haghighat
authors.affiliation: Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran.|Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Masud
authors.initials: M
authors.lastname: Yunesian
authors.affiliation: Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Ramin
authors.initials: R
authors.lastname: Nabizadeh
authors.affiliation: Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.|Center for Solid Waste Research (CSWR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Amir Hossein
authors.initials: AH
authors.lastname: Mahvi
authors.affiliation: Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad Hadi
authors.initials: MH
authors.lastname: Dehghani
authors.affiliation: Wastewater Laboratory, Shiraz Health Center, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Rahim
authors.initials: R
authors.lastname: Davani
authors.affiliation: Basic Studies of Water Resources, Fars South Center, Larestan, Iran.
authors.forename: Abd-Rasool
authors.initials: AR
authors.lastname: Aminian
authors.affiliation: Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran.|Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mansour
authors.initials: M
authors.lastname: Shamsipour
authors.affiliation: Young Researchers and Elite Club, Sardasht Branch, Islamic Azad University, Sardasht, Iran.|Department of Geography and Urban Planning, Payame Noor University, Sardasht, Iran.
authors.forename: Naser
authors.initials: N
authors.lastname: Hassanzadeh
authors.affiliation: Department of Social Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Faramarzi
authors.affiliation: Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.|Center for Water Quality Research (CWQR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Mesdaghinia
mesh_terms: D060766:Drinking Water / Q000737:chemistry*; D004781:Environmental Exposure; D004784:Environmental Monitoring; D005459:Fluorides / Q000032:analysis*; D060587:Groundwater / Q000737:chemistry*; D007492:Iran; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D060766:Drinking Water; D014874:Water Pollutants, Chemical; D005459:Fluorides
keywords: Fluoride toxicity; Groundwater resources; Iran; Mann–Kendall trend test; Spatial variability; Spatiotemporal