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Contents of heavy metals in various bran layers of rice collected from Kyeong Nam province in 1978, were determined. The components of crude protein, crude fat, crude cellulose, and ash in all the rice samples were found to be most concentrated in the rice of each layer of brown, 70% polished, and 90% polished, but the contents of crude protein (9.22%), crude fat (1.16%), crude cellulose (1.01%), and ash (0.38%) in polished rice decreased rapidly. On the other hand, the amounts of nitrogen-free extract in the rice were showed increasingly toward the inner layer and those of polished rice were 75.54%. The contents of lead, zinc, nickel, cadmium, and arsenic in bran layer of rice decreased in order of that of 90% polished, 70% polished, brown, and polished rice. Their amounts in polished rice were lead, 0.054∼0.610ppm zinc, 9.830∼19.093ppm; nickel, trace-1.776ppm; cadmium, trace-0.039ppm; arsenic, ND-0.170ppm. It was shown that copper was more concentrated in the layer of 900 polished rice (0.581∼1.476ppm), and iron more in brown rice (27.971∼66.569ppm) than in any other portion, whereas mercury (0.006∼0.072ppm), chromium (1.538∼7.822ppm), and manganese (57.371∼179.252ppm) were much contained in the layer of 70% polished rice. Their amounts in polished rice were copper, 0.218∼0.858ppm; iron, 1.480∼9.573ppm, mercury, 0.006∼0.027ppm; chromium, ND-1.520ppm; and manganese, 6.730∼11.562ppm.
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