Urine Fluoride Level of School Children in Different Fluoride
Contaminated Geothermal Water Sources Area in Chiang Mai
Chatpat Kongpun 1
Supoj Chamnarnprai 2
Phenphichar Wanachantararak 3
Jumpol Promsaka Na Sakon Nakorn 4
There is a variation in fluorosis risk area in Chiang Mai Province depends on different
fluoride contamination amount in geothermal water sources. Thus, the urine fluoride level is
the most sensitive and promising biomarker in school children for monitoring of actual daily
fluoride intake and excrete. It also benefits for early warning and prevention in dental
fluorosis surveillance program in school children by the reason that highly fluoride intake is
detected before the dental fluorosis occurs. This study was done by collecting urine sample
from school children in 3 subdistricts that have different fluoride contamination amount in
geothermal water sources. The spot urine samples were analyzed by ISE technique to
determine fluoride level in urine that reflects the fluoride intake within 3-7 days. Yang Pao
subdistict in Om Koi district is the low risk area that have fluoride amount in both drinking
and cooking water nearly to 0.10 - 0.20 mg/L. Mae Pu Kha subdistrict in San Kamphaeng
district is the moderrate risk area that have fluoride amount in drinking water and cooking
water between 0.04 - 2.76 mg/L and 0.04 - 2.98 mg/L respectively. Buak Khang subdistricts
in San Kamphaeng district is the moderate risk area that have fluoride amount in drinking
water and cooking water between 0.00 - 0.58 mg/L and 0.00 - 4.78 mg/L respectively. The
urine fluoride concentration in high risk area, Buak Khang subdistrict, was between 0.00 6.89 mg/L (2.72-3.46 mg/L). The urine fluoride concentration in moderate risk area, Mae Pu
Kha subdistrict, was between 0.00 - 2.35 mg/L (1.25 – 1.35 mg/L). The urine fluoride
concentration in low risk area, Yang Pao subdistrict, was between 0.00 - 1.88 mg/L (0.77 –
0.90 mg/L). There was significantly different between urine fluoride concentrations among all
districts. The prevalence of dental fluorosis in each subdistrict was difference and relatively
associated with the urine fluoride level.
1,2,4
Intercountry Centre for Oral Health, Department of Health, Ministry of Public Health,
Thailand
3
The Dental Research Center, Faculty of Dentistry, Chiang Mai University
Keyword: Urine Fluoride, Dental Fluorosis, Fluoride Intake, Fluoride Excretion