Effect of open storage and peeling on the fluorine content of dried corn in Zhaotong city, Yunnan province, a fluorosis area / 中国地方病学杂志

ABSTRACT

Objective To explore the effect of open storage and peeling on the fluorine content of dried com in order to provide a scientific basis for prevention and treatment of coal-combustion fluorosis. Methods In October 2006, 34 samples of freshly dried and 3-month old dried com were sampled in Zhenxiong county, Zhaotong city, Yunnan province. Fluorine content in corn was determined by combustion-hydrolysis-ion selective electrode method. Results The average fluorine content of freshly dried corn by coal-combustion was (4.29 ±1.87)mg/kg,and increased to (6.64±2.64)mg/kg after they had been openly stored for three months and the average content increased by 54.74%. But if corn was peeled off, their fluorine content decreased to (5.03±2.04)mg/kg at a rate of 24.25%. The amount of fluorine absorbed by the skin of corn was more than other parts of com during corn desiccation. Conclusions The inhabitants in coal-combustion fluorosis areas ingest less fluorine through dry com if they eat the peeled corn and take measures to keep it airtight and moisture-proof during storage thus reducing the harm of coal-combustion fluorosis.