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Objective To understand the water quality of self-supply wells in four provinces of northern China (Heilongjiang, Beijing, Inner Mongolia and Tibet), so as to provide a reference for supervision and management of self-supply wells. Methods Water were sampled from 233 self-supply wells in four northern provinces of China according to standard examination methods for drinking water (GB/T 5750-2006). In total, The samples were tested for 27 kinds of water quality parameters involving sensory properties, chemistry, bacteriology and toxicology, and then evaluated. Results The total unqualified rate of water quality in self-supply well water in four northern provinces of China was 52.36%. The water quality varied greatly among provinces. As for Heilongjiang, the main unqualified indicators of self-supply wells water involved turbidity, visible to the naked eye, manganese, arsenic and nitrate. In relation to Beijing, these referred to the nitrate and microorganism. In case of Inner Mongolia province, these included sulfate and fluoride. With reference to Tibet, these were zinc and chloride. Conclusions To ensure the safety of drinking water for residents, the management, disinfection and purifying measures of self-supply wells should be strengthened basing on their regional differences and water quality characteristics.
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Objective To find out about the sanitary conditions of drinking water along the border line of Inner Mongolia via safety evaluation of drinking water along the border line of Inner Mongolia.Methods 108 samples of drinking water along the border line of Inner Mongolia(70 samples of self-supply source water,21 ones of self-supply tap water and 17 ones of municipal tap water)were collected.Hygienic evaluation of sensory indexes, normal chemical indexes, toxicological indexes and microbiology indexes of water quality was performed according to hygienic standards for drinking water(GB 5749—2006).Results 58 samples were qualified with a total qualified rate of 53.7%.The unqualified rate of the total number of coliforms was the highest(20.4%),followed by fluoride(19.4%).As for deep wells, shallow wells and surface water,there was no statistically significant difference.Compared with municipal tap water,the unqualified rate of self-supply water(28.6%)was higher(17.7%).Conclusion The qualified rate along the border line of Inner Mongolia of drinking water is low.Treatment and disinfection facilities for drinking water,detection devices of water quality are needed.The cleaning and disinfection of storage tanks should be performed periodically in oder to prevent waterborne infectious diseases.
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<p><b>OBJECTIVE</b>To investigate the potential involvement of DMT1 (IRE) protein in the brain vascular system in vivo during Pb exposure.</p><p><b>METHODS</b>Three groups of male Sprague-Dawley rats were exposed to Pb in drinking water, among which two groups were concurrently administered by oral gavage once every other day as the low and high Fe treatment group, respectively, for 6 weeks. At the same time, the group only supplied with high Fe was also set as a reference. The animals were decapitated, then brain capillary-rich fraction was isolate from cerebral cortex. Western blot method was used to identify protein expression, and RT-PCR to detect the change of the mRNA.</p><p><b>RESULTS</b>Pb exposure significantly increased Pb concentrations in cerebral cortex. Low Fe dose significantly reduced the cortex Pb levels, However, high Fe dose increased the cortex Pb levels. Interestingly, changes of DMT1 (IRE) protein in brain capillary-rich fraction were highly related to the Pb level, but those of DMT1 (IRE) mRNA were not significantly different. Moreover, the consistent changes in the levels of p-ERK1/2 or IRP1 with the changes in the levels of DMT1 (IRE).</p><p><b>CONCLUSION</b>These results suggest that Pb is transported into the brain through DMT1 (IRE), and the ERK MAPK pathway is involved in DMT1 (IRE)-mediated transport regulation in brain vascular system in vivo.</p>