Rice oil poisoning

Ryan JJ, Levesque D, Panopio LG, etal. 1993a. Elimination of polychlorinated dibenzofiirans (PCDFs) and polychlorinated biphenyls (PCBs) from human blood in the Yusho and Yu-Cheng rice oil poisonings. Arch Environ Contain Toxicol 24 504-512. 

MasudaY. 1994. The Yusho rice oil poisoning incident. In Schecter A., ed. Dioxins and health. 

Human poisonings from consumption of PCB mixtures include the well-known Yusho rice oil poisoning in Japan (1968), where PCB fluids became mixed inadvertently with rice oil used for cooking. The actual level of contamination of the rice oil was low, about 0.2%. About 2000 people were poisoned in 1978 in a similar incident in Yu-Cheng, Taiwan. The principal symptoms in both cases were related to headache. Adipose tissue from Yusho patients was found to contain up to 75 ppm of PCBs. Cancer development was not statistically connected with people poisoning by PCBs. Later investigations have shown that the toxicity of these PCB-contaminated rice oils was probably not primarily due to the PCBs themselves, but to the traces of polychlorinated dibenzofurans (PCDFs), which they contained. We will consider the formation of furans and dioxins in the following section. 

In addition, excess respiratory cancer was noted by Fingerhut et al. [187]. These results are also supported by significantly increased mortality from lung and liver cancers subsequent to the Japanese rice oil poisoning accident where exposure to PCDFs and PCBs occurred. Again, while smoking as a confounder cannot be totally eliminated as a potential explanation of these results,... 

Kuratsune M, Yoshimura T, Matsuzaka J, Yamasuchi A Yusho, a poisoning caused by rice oil contaminated with polychlorinated biphenyls. HSMHA Health Rep 36 1083-1091, 1971... 

Kuratsune, M., T. Yoshimura, J. Matsuzaka and A. Yamaguchi, "Epidemiologic Study (on) Yusho, A Poisoning caused by Ingestion of Rice Oil contaminated with a Commercial Brand of Polychlorinated Biphenyls," Environ. Health Perspect.. Exp. Issue No. 1, pp. 119-28 (Apr. 1972). 

The adverse human impacts of PCBs have been investigated in occupationally exposed workers as well as individuals poisoned with PCB-contaminated rice oil in Japan and Taiwan (Yusho and Yu-Cheng poisonings).91,107-109 In addition, recent studies have shown a correlation with in utero exposure to PCBs and subtle neurodevelopmental and neurobehavioural deficits in children.110 These effects were observed in children with relatively low-level environmental exposure to PCBs and thus have raised concerns regarding the potential adverse effects of low level in utero exposure to organochlorine compounds during critical periods of foetal development. 

The potential toxicity of PCBs to humans first came into the public arena in 1968, when over 1,500 people around Fukuoka in south-west Japan were poisoned by eating food cooked in rice oil contaminated with PCBs. This was not a single (acute) poisoning incident as the victims used the contaminated rice oil for cooking for some three months. The oil had become contaminated with PCBs as a result of a leak in the machinery in the plant producing the rice oil. People started to suffer from various diseases, and the illness became known as Yusho disease (meaning rice oil disease). Most prominent was chloracne, a severe effect on the skin which is also caused by dioxins. Babies born to women who were exposed also showed symptoms of the disease. Eventually some 2,000 cases of Yusho disease were recorded. 

Evaluation of Human Studies. Limited information on immunological effects of PCBs in humans is available from studies of people exposed in the workplace, by consumption of contaminated fish and other marine foods, by consumption of contaminated rice oil in the Yusho and Yu-Cheng poisoning incidents, and via general enviromnental exposures. A comparison of PCB levels in blood and breast milk in some of these studies is included in Appendix A. 

Menstrual irregularities (i.e., altered intervals, duration, and flow) were observed in women exposed during the Yusho poisoning incident (Kusuda 1971). Heating of the PCB-contaminated rice oil also resulted in the formation of other contaminants of concern (i.e., dibenzofurans and ter-, and... 

Kusuda M. 1971. A study on the sexual functions of women suffering from rice-bran oil poisoning. Sanka to Fujinka 38 1062-1072. 

Japanese Yusho food PCB contamination registrants versus national death rates 887 males 1968-1983 1968 (poisoning incident) SMR 3.26 (no Cl p<0.01) Heated PCB-contaminated rice oil also contained PCDFs and other contaminants. The analysis combined cancers cf the lung. Kuratsune et al. 1987... 

Intestinal cancer mortality Taiwanese Yu-Chengfood PCB contamination victims versus Taiwan national and local reference mortality rates 1,940 (929 males, 1,011 females) 1979-1991 1979 (poisoning incident) SMR National 19.76 (95% Cl= 0.5-110.3) Local 26.46 (95% Cl= 0.67-147.4) Heated PCB-contaminated rice oil also contained PCDFs and other contaminated. The analysis focused on deaths from cancer of the small intestine in males one observed death. No parallel analysis was reported in females. Hsieh et al. 1996... 

Yusho and Yu-Cheng Incidents. Several panelists recommended that ATSDR consider including more information on the Yusho and Yu-Cheng poisoning incidents from Japan and Taiwan, respectively, in the Toxicological Profile for PCBs. These incidents involved two populations that consumed rice oil contaminated with complex mixtures of chemicals, which included furans, PCBs, and other compounds. Analyses of these incidents are documented in... 

These substances have already caused a number of ecological catastrophes. In 1968 more than 1200 people were poisoned in Japan, by consuming rice oil polluted with 0.1% of commercial polychlorodiphenyl Kanechlor 400. On heating the rice oil, the heating medium (Kanechlor) penetrated through a crack in a heat exchanger into the product. The rice oil became contaminated with 5 ppm of tetra- and pentachloro-dibenzofu-rans and it was shown that the main component was 2,3,7,8-TCDF in a concentration of 0.45 ppm. 

Et>idamiological study on Yusho, a poisoning caused by ingestion of rice oil contaminated with a commercial brand of polychlorinated biphenyls. Environ. Health Eferspect. 1 119 (1972). 

Mass poisoning of more than 1000 people by contaminated rice oil (Yusho disease, Japan)... 

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