Poisoning by Coal Smoke Containing Arsenic and Fluoride

An investigation was made into a disease involving skin pigmentation, keratosis of the hands and feet, dental discoloration, and generalized bone and joint pain, stiffness and rigidity, in the village of Bazhi, Zhijin County, Guizhou Province, People's Republic of China. Measurements were made of the arsenic and fluoride levels of coal, water, air, food, urine and hair in Bazhi and a control village, Xinzhai, in which coal with a low arsenic content was used. Up to 188 persons, including children, in Bazhi and 752 in Xinzhai, were examined for the presence of chronic arsenism, skeletal fluorosis, dental fluorosis and electrocardiogram abnormalities. The coal in Bazhi was found to contain high levels of arsenic and fluoride resulting, after burning in homes without an adequate chimney system for the removal of smoke, in pollution of air and food with arsenic and fluoride. The coal in Xinzhai did not cause arsenic pollution but did produce a higher level of fluoride pollution. Chronic arsenism was found to affect 30% of the persons in Bazhi but none in Xinzhai. In both villages 100% of the children aged 8-15 years had dental fluorosis. Skeletal fluorosis was present in 47.5% of the adults in Bazhi and 56.1% of those in Xinzhai (difference not significant). It was concluded that the endemic disease in Bazhi was caused by pollution by coal smoke containing arsenic and fluoride. It is suggested that arsenic may act synergistically with fluoride so that a lower level of fluoride may produce fluoride toxicity with dental and skeletal fluorosis.