According to the milling degree (unhulled, brown, 70% polished, and 90% polished rice), cropping areas (Sabong, Myeungsuk, Hadong, and Sanchung), and variety of rices (Yusin and Milyang), the contents of copper, lead, zinc, nickel, mercury, cadmium, chromium, and manganese were analyzed in order to investigate heavy metals in the rice of Kyeong Nam district for two years(1976-1977) by the atomic absorption spectrophotometer. The results obtained were as follows;
1. The contents of heavy metals in all the sample rices observed in this experiment were decreased with the increase of milling degree, but significant difference of the heavy metals was not observed among the cropping areas and variety of rites.
2. The contents of heavy metals were copper, 0.80-2.89 ppm; zinc, 3.23-17.60 ppm; manganese, 6.72-70.25 ppm; and lead, ND-0.64 ppm.
3. The contents of nickel and chromium in unhulled rice were in the range of 2.04-40.64 and 5.09-39.95 ppm, respectively, but these heavy metals were in trace for 90% polished rice.
4. The mercury and cadmium were in trace for some unhulled rice, but they were not detected in polished rice.
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