ABSTRACT
Objective To make clear the fluorine content distribution in drinking water of residents in Hubei Province,draw a provincial distribution map of high-fluorine water and provide scientific basis for formulating refined prevention and control measures of drinking water type fluorosis in Hubei Province.Methods In 116 counties of Hubei Province,including development zones,scenic zones and farmlands,drinking water of residents was sampled according to different water supplies (centralized water supply,small centralized water supply in rual areas and decentralized water supply) from 2013 to 2015.For a centralized water supply,one sample was collected from the source water and the tap water each and at least 3 samples were collected for decentralized water supply in a village.Selective electrode method was used to detect the water fluorine content and ArcGIS 10.2 was used to draw distribution map of high-fluorine water at county level.Results A total of 38 284 water samples were collected,the median of fluorine content was 0.21 mg/L.The highest detective rate of all types of water supply with high fluorine content was pressure water well (64/100,64.0％) and high-fluorine water sample was not found in the reservoir.The high-fluorine water sources from centralized water supplies were distributed dispersedly in the north-west and the east of Hubei Province and those from decentralized water supplies were distributed dispersedly in the middle-north and the east of Hubei Province.Conclusions Fluorine concentration in drinking water is generally low.However,there are still some high-fluorine water supplies which should be reported to Hubei Provincial Water Resources Department as soon as possible.Moreover,there is a phenomenon of fluorine rebounce in the water reduction project,and managements of those projects should be strengthened.
ABSTRACT
Objective To make clear the geography distribution of iodine in drinking water in Hubei Province,and make a provincial distribution map and provide scientific basis for formulating refined prevention and control measures to iodine deficiency disorders in Hubei Province.Methods In 116 counties of Hubei Province,including development zones,scenic zones and farmlands,drinking water samples were collected according to different water supplies (centralized water supply and decentralized water supply).One source water and a tap water sample were collected for a centralized water supply and at least 3 samples for decentralized water supply in a village were collected.Water iodine quantitative detection kit was used to detect the water iodine content and ArcGIS 10.2 to draw the distribution map of water iodine at county level.Results Totally 38 275 water samples were collected,and 83.47％ (31 950/38 275) of them were came from decentralized water supply.The water-iodine-concentration median was 4.89 μg/L and 66.28％ (25 368/38 275) of them were lower than 10 μg/L.Samples with water-iodine-concentration higher than 150 μg/L were 0.15％ (56/38 275),which were distributed in the southern,northern and centre Hubei Province and a few in the east.Conclusions Iodine concentration in drinking water is generally low in Hubei Province.As an important and main measure to prevent iodine deficiency disorders,universal salt iodization (USI) should be carried out as a long-term measure.Districts of iodine content higher than 150 μg/L should be reported to Hubei Provincial Water Resources Department as soon as possible.