clay and Fluorosis--Dental

Pilot experiments were carried out to reduce the fluorine (F) and arsenic (As) pollution of roasted corn dried by open ovens in "coal-burning" fluorosis area Yunnan, China. The results indicated that the average emission amount of F and As in briquettes in experimental group were 29.20mg/kg and 0.76 mg/kg in Xiaolongdong, and 46.8 mg/kg and 0.54 mg/kg in Mangbu respectively. The results also indicated that the fixing rate of F and As in briquettes in experimental group was more than 4 times and 1.2 times of that in control group respectively. The average concentration of F and As in roasted corn in experimental group were 3.86 mg/kg and 13.23 μg/kg in Xiaolongdong, and 4.77 mg/kg and 122.96 μg/kg in Mangbu respectively, which reduced by more than 65% and 75% respectively compared with that in control group. Adding local natural calcium-based materials in briquettes can reduce the emission of F and As and their pollution on roasted corn largely, and thus will reduce the risk of fluorosis for residents greatly in "coal-burning" fluorosis area of southwestern China.

Topics: Air Pollutants; Air Pollution, Indoor; Aluminum Silicates; Arsenic; China; Clay; Coal; Fluorine; Fluorosis, Dental; Food Contamination; Humans; Zea mays

A study was carried out to assess toxicological risk from the fluoride (F) exposure due to ingestion of vegetables and cereal crops such as rice and wheat grown in potentially fluoridated area (brick kiln and sodic areas), of different age groups in Unnao district, Uttar Pradesh, India. Fluoride contents in vegetables and cereal were found to be in the order brick kiln sites>sodic sites>normal sites. Among vegetables maximum F concentration was found in spinach and mint, whereas in cereal crops, wheat accumulated more F than rice. The exposure dose of F was determined using estimated daily intake (EDI) and bio-concentration factor (BCF) of F. The children of age group 3-14 years in the potentially fluoridated area were found to be at the risk of fluorosis. The mean BCF value of F was the highest in mint (36.6 mg/kg(dwt) plant/mg/kg(dwt) soil), followed by spinach (33.99 mg/kg(dwt) plant.mg/kg(dwt) soil).

Topics: Adolescent; Adult; Aged; Aluminum Silicates; Child; Child, Preschool; Clay; Diet; Edible Grain; Environmental Exposure; Fluoridation; Fluorides; Fluorosis, Dental; Food Contamination; Humans; Hydrogen-Ion Concentration; India; Middle Aged; Nutrition Surveys; Risk Assessment; Soil; Soil Pollutants; Vegetables; Young Adult

Topics: Aluminum Silicates; Animals; Cardiovascular Diseases; Clay; Environment; Fluorides; Fluorosis, Dental; Geological Phenomena; Geology; Health; Humans; Iodine; Magnesium; Pica; Radiation Dosage; Radiation Effects; Radiation, Ionizing; Soil; Sri Lanka; Trace Elements; Water Supply

To study the dental fluorosis and caries in the permanent teeth of 12 to 13-year-old children in fluorosis-endemic areas; to assess the relationship between fluorosis and the fluoride content of the drinking water and the relationship between caries and the fluoride content of the water; finally, to analyze the effect of fluoride intake and water stored in clay pots on dental fluorosis.. 477 children were divided into 5 groups (A to E) according to the fluoride concentration of the waters, i.e. by 0.4, 1.0, 1.8, 3.5, and 5.6 mg F/l, respectively. Dental fluorosis was assessed by TF score and caries by the DMF-T index. A questionnaire was used to obtain information about water storage and other information relevant to children's fluoride intake.. A positive relationship was found between the mean TF scores and the water fluoride concentration. In groups B and D, the TF score was higher in 13-year-olds than in 12-year-olds. Caries prevalence and mean DMF-T ranged from 2.6% and 0.03 (group E) to 22.1% and 0.38 (group A). Storage of water in clay pots seemed to increase the severity of fluorosis slightly, and to decrease the caries prevalence.. Defluoridation of drinking water, or--alternatively--the provision of low-fluoride water sources, should be given high priority in the examined Shaanxi rural areas. Fluoride concentration of drinking water should be maximum 0.6 mg/l. Storage of water in the local clay pots may increase the severity of dental fluorosis.

Topics: Adolescent; Aluminum Silicates; Child; China; Clay; Cooking and Eating Utensils; Dental Caries; Dentition, Permanent; Epidemiologic Methods; Female; Fluorides; Fluorosis, Dental; Humans; Male; Rural Population; Water Supply