Effect of food drying methods on fluoride content in maize and pepper in coal-burning type of fluorosis regions / 中国地方病学杂志

ABSTRACT

Objective To explore the effect of different processing and drying methods of corn and hot pepper on fluorine content in coal-burning type of the endemic fluorosis areas, and to screen food processing and drying methods which meet the quality requirements of grain drying and able to effectively reduce the total fluoride intake of local population. Methods Farmers of endemic fluorosis area in Bijie, Guizhou province were divided into 3 groups sun-baked drying group, stove drying group with air-tight cover and stove drying group with no cover, 10 households in each group. Corn and fresh hot pepper and samples dried for 2 weeks, or 1, 3, 6-month were collected, and water and fluoride content were detected, and the total daily fluoride intake were calculated in accordance with the "Determination of Water in Food" (GB/T 5009.3-2003) and "Determination of Fluorine in Foods"(GB/T 5009.18-2003). Results Fluoride content in fresh corn and dried for 2 weeks, or 1, 3, 6-month [of sunbaked drying group (1.40 ± 0.16), (1.56 ± 0.14), (2.15 ± 0.47), (2.70 ± 0.64), (4.06 ± 1.75)mg/kg, stove drying group with air-tight cover (1.41 ± 0.16), (2.39 ± 0.56), (4.60 ± 0.97), (8.46 ± 5.55), (11.36 ± 3.60)mg/kg,stove drying group with no cover (1.40 ± 0.13), (4.69 ± 3.97), (4.47 ± 2.77), (9.65 ± 6.47), (26.12 ± 14.52)mg/kg] and pepper[sun-baked drying group (5.41 ± 1.61), (16.60 ± 7.62), (32.60 ± 7.88), (50.26 ± 17.60),(240.20 ± 272.49)mg/kg, stove drying group with air-tight cover (754 ± 2.95), (3238 ± 11.50), (119.18 ± 156.45),(224.00 ± 196.58), (495.70 ± 417.29)mg/kg, stove drying group with no cover (4.82 ± 1.25), (44.30 ± 13.48),(122.89 ± 66.43), (334.23 ± 166.05), (531.01 ± 397.40)mg/kg] increased with elongation of drying time, and the group difference was significant(F = 44.77, 128.71, 126.87, 41.61, 53.63, 170.63, all P ＜ 0.05), with the largest rate of increase in stove drying group with no cover, and the lowest in sun-baked drying group;fluoride was significantly lower (t = 7.93,63.07,5.36,11.98,55.76,7.45, all P ＜ 0.05) after sample washing;total fluoride intake per person per day was 2.57 mg in local adult when ate washed and sun-baked corn, peppers, the total fluoride intake were 5.92, 8.14 mg when ate the food processed by other two drying methods and washed corn, peppers,respectively. Conclusions In the coal-burning type of fluorosis endemic area, should take appropriate health education measures, and instruct local residents to use sun bake their edible corn and pepper for human consumption, and cultivate a habit of washing corn and pepper before cooking, which can reduce the population total fluoride intake, and control endemic fluorosis.