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Published in: BMC Public Health 1/2013

Open Access 01-12-2013 | Research article

Change of urinary fluoride and bone metabolism indicators in the endemic fluorosis areas of southern china after supplying low fluoride public water

Authors: Shaoxian Chen, Boling Li, Shao Lin, Yixiang Huang, Xinhua Zhao, Min Zhang, Yuan Xia, Xiaoheng Fang, Junyi Wang, Syni-An Hwang, Shouyi Yu

Published in: BMC Public Health | Issue 1/2013

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Abstract

Background

Few studies have evaluated health impacts, especially biomarker changes, following implementation of a new environmental policy. This study examined changes in water fluoride, urinary fluoride (UF), and bone metabolism indicators in children after supplying low fluoride public water in endemic fluorosis areas of Southern China. We also assessed the relationship between UF and serum osteocalcin (BGP), calcitonin (CT), alkaline phosphatase (ALP), and bone mineral density to identify the most sensitive bone metabolism indicators related to fluoride exposure.

Methods

Four fluorosis-endemic villages (intervention villages) in Guangdong, China were randomly selected to receive low-fluoride water. One non-endemic fluorosis village with similar socio-economic status, living conditions, and health care access, was selected as the control group. 120 children aged 6-12 years old were randomly chosen from local schools in each village for the study. Water and urinary fluoride content as well as serum BGP, CT, ALP and bone mineral density were measured by the standard methods and compared between the children residing in the intervention villages and the control village. Benchmark dose (BMD) and benchmark dose lower limit (BMDL) were calculated for each bone damage indicator.

Results

Our study found that after water source change, fluoride concentrations in drinking water in all intervention villages (A-D) were significantly reduced to 0.11 mg/l, similar to that in the control village (E). Except for Village A where water change has only been taken place for 6 years, urinary fluoride concentrations in children of the intervention villages were lower or comparable to those in the control village after 10 years of supplying new public water. The values of almost all bone indicators in children living in Villages B-D and ALP in Village A were either lower or similar to those in the control village after the intervention. CT and BGP are sensitive bone metabolism indicators related to UF. While assessing the temporal trend of different abnormal bone indicators after the intervention, bone mineral density showed the most stable and the lowest abnormal rates over time.

Conclusions

Our results suggest that supplying low fluoride public water in Southern China is successful as measured by the reduction of fluoride in water and urine, and changes in various bone indicators to normal levels. A comparison of four bone indicators showed CT and BGP to be the most sensitive indicators.
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Metadata
Title
Change of urinary fluoride and bone metabolism indicators in the endemic fluorosis areas of southern china after supplying low fluoride public water
Authors
Shaoxian Chen
Boling Li
Shao Lin
Yixiang Huang
Xinhua Zhao
Min Zhang
Yuan Xia
Xiaoheng Fang
Junyi Wang
Syni-An Hwang
Shouyi Yu
Publication date
01-12-2013
Publisher
BioMed Central
Published in
BMC Public Health / Issue 1/2013
Electronic ISSN: 1471-2458
DOI
https://doi.org/10.1186/1471-2458-13-156

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