Yu-Cheng disease

However, a confounding factor in both Yusho and Yu-Cheng diseases... 

Because some of the symptoms of Yusho and Yu-Cheng diseases (see Table 2) were similar to those caused by PCDFs rather than PCBs, it has been concluded that these contaminants are the causative agents. Indeed the level of PCDFs in the blood of victims correlates with the symptoms whereas the blood level of PCBs does not. 

Mass poisoning of more than 2000 people by contaminated rice oil (Yu-cheng disease, Taiwan) federal law banned US production of PCBs... 

TCDD can produce respiratory irritation, but the findings from controlled epidemiologic studies do not support an association between 2,3,7,8-TCDD exposure and chronic respiratory disease. It should be noted, however, that chronic bronchitis and related effects were observed in many Yusho and Yu-Cheng patients, who were exposed to the structurally related CDFs (ATSDR 1994). 

Soog D-K, Ling Y-C. 1997. Reassessment of PCDD/DFs and Co-PCBs toxicity in contaminated rice-bran oil responsible for the disease Yu-Cheng . Chemosphere 34 1579-1586. 

Johnson, P.J., Leung, N., Cheng, P., Welby, C., Leung, T., Lau, W.Y., Yu, S., and Ho, S., 1997, Hepatoma-specific alpha-fetoprotein may perrmit preclinical diagnosis of malignant change in patients with chronic liver disease. Brit. J. Cancer, 75 236 - 242. 

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