ABSTRACT
In this study, fluorine concentrations in drinking water and in urine of residents from a fluorine exposure area in China were tested. DMFT (average number of decayed, missing and filled teeth) of local residents in four age groups were also determined. The results of the study indicate that in fluorine exposure areas, there is a strictly positive correlation between fluorine content in urine and the fluorine content in drinking water. Effect of dental caries by high fluorine content drinking water is different for the different age groups. High fluorine content drinking water is more dangerous for 15-and 18-year-old groups than 5- and 12-year-old groups.
Subject(s)
Dental Caries/epidemiology , Fluorine/analysis , Water Supply/analysis , Adolescent , Child , Child, Preschool , China , Dental Caries/etiology , Environmental Monitoring , Epidemiological Monitoring , Fluorine/urine , HumansABSTRACT
<p><b>OBJECTIVE</b>To study iodine nutrition of pregnant women in different occasions and thyroid function of their neonates.</p><p><b>METHODS</b>Urinary iodine of pregnant women and their serum T(3), T(4), FT(3), FT(4) were determined by chloric acid-digestion thermostatic assay and RIA, TSH determination by IRMA; neonatal umbilical cord blood TSH was determined by ELISA.</p><p><b>RESULTS</b>Median urinary iodine of pregnant women were 206.3 microg/L, 161.4 microg/L, 203.3 microg/L at 10 - 14 (first occasion), 23 - 27 (second occasion) and 39 - 40 (third occasion) week but the percentage that lower than 100 microg/L were 14.6%, 17.1%, 11.1% respectively. Serum T(3), T(4) of pregnant women was significantly higher than those women of premarital health inspection (PHIW, P < 0.001). The difference of serum T(3), T(4) of pregnant women at 10 - 14 and 39 - 40 week was not significant. Serum FT(3), FT(4) of pregnant women at 39 - 40 week were 2.61 +/- 0.47 pmol/L and 5.50 +/- 1.57 pmol/L respectively. The difference of serum TSH concentration at third occasion and first occasion of pre-pregnancy was significant but the difference of TSH frequency distribution in three groups was not significant (chi(2) = 1.138, P > 0.5). Blood TSH median neonatal umbilical cord was 1.99 mU/L but the percentage that higher than 5 mU/L was 9.4%.</p><p><b>CONCLUSION</b>For those areas with high iodized salt coverage, pregnant women had had sufficient iodine supplement and good thyroid function. The percentage of neonates from iodine sufficient pregnant women with TSH > 5 mU/L was lower than 10%. Using the normal range of nonpregnant FT(3) and FT(4) to estimate the thyroid function of pregnant women could cause mis diagnosis.</p>
