Yusho

NOBORU K K, YUSHO T (1997) Oryzanol containing cosmetics. J P 7032078 (Chem Abstr. 1998, 14269x). 

Nakanishi, Y. et al., Respiratory involvement and immune status in Yusho patients, Environ. Health Perspect., 59, 31, 1985. 

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... 

Masuda Y, Yoshimura H Chemical analysis and toxicity of polychlorinated biphenyls and dibenzofurans in relation to Yusho. f Toxicol Sci 7(3) 161-175, 1982... 

Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are two series of tricyclic aromatic compounds which exhibit similar physical and chemical properties. Some of these compounds have extraordinary toxic properties and were the subject of much concern. They have been involved in accidents like the Yusho accident in Japan 1968 l 9 the intoxication at horse arenas in Missouri, USA in 1971 (2.) and the accident near Seveso, Italy in 1976 (3.). The chemical structures and the numbering of these hazardous compounds are given below. 

A similar relationship between PCDF isomers retained and apparently excreted has been observed for patients with the Yusho disease, an intoxication by a rice oil contaminated with PCBs and PCDFs. The contaminated rice oil and liver samples from two of the patients were analyzed and all the major PCDFs were identified. A comparison revealed that none of the isomers retained had two vicinal hydrogenated C-atoms in any of the two... 

Figure 3. PCDF isomers retained and excreted from the liver of Yusho patients...

Thus, human exposure to PCBs in Japan (Yusho accident) and China has been associated with increased respiratory infections and decreased levels of immunoglobulins in serum. In animals exposed to these compounds, there is atrophy of both primary and secondary lymphoid organs, lower circulating immunoglobulins, and decreased antibody responses after exposure to antigens. Similarly, the exposure of both humans and farm animals to polybrominated biphenyls, which occurred in Michigan in 1973, resulted in depressed immune responses. 

By May of 1975 the number of Yusho patients had risen to 1291 (ref. 136, pp. 40ff). Common symptoms of toxicity were the characteristic acnei form eruption and eye discharges, along with swelling of the upper eyelids previously described, hyperemia of the conjunctiva, hyperpigmentation of skin, mucous membranes and nails (ref. 146). 

Discharges from the acneiform eruptions of two patients analyzed at 32 and 45 ppm PCBs. An 18 year old male showed ca. 75 and 13 ppm in subcutaneous fat samples taken from his face and abdomen, respectively. GLC patterns similar to those in contaminated rice oils were found in the human samples examined, including those from fetal and placental tissues. Tissues from a stillborn infant (October 1968) were preserved for later analysis. These had PCB concentrations in liver, skin and fat of 1.8, 1.2 and 0.1 ppm, respectively. The pregnant mother had been diagnosed as a severe case of Yusho. First trimester PCB concentrations reported for 19 embryos were low (<2ppb). Second and third trimester were successively higher (Table 9) ... 

PCBs did have a marked effect on both fetal and post-natal development, growth and mortality. In view of the possible relationship between malignant melanoma and exposure to PCBs, long-term follow-up studies should be pursued on the surviving offspring of highly exposed mothers as well as on the mothers themselves. One study of nine post-Yusho offspring exposed to PCB via breast milk reported apathy, enervation, hypotonia and a lack of endurance in three of these children for more than 5 years ref. 151). 

PCBs and PCDFs (ppm) In Fat from Three Yusho Patients at Autopsy... 

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). 

There have been accidental releases of pollutants that have cause effects on humans and wildlife, such as Yucheng in Taiwan, Yusho in Japan (Ikeda, 1996), PCB contamination of poultry in Belgium (Bernard et al., 1999), Seveso in Italy (Mocarelli, 2001), and dioxin contamination by redistribution and burial of contaminated soils at Love Canal in the USA (Vianna, 1983). However, despite intensive and rapid industrialization and urbanization, such massive POPs related cases have not occurred in South Korea. Since the 1990s, monitoring South Korea has rarely found POP concentrations as great as parts per million (ppm). 

Ikeda, M., 1996. Comparison of clinical picture between Yusho/Yucheng cases and occupational PCB poisoning cases. Chemosphere 32, 559-566. 

Nakanishi, Y., Shigematsu, N., Kurita, Y., Matsuba, K., Hanegae, H., Ishimaru, S., Kawazoe, Y., 1985. Respiratory involvement and immune status in Yusho patients. Environ. Health Perspect. 59, 31-36. 

Ryan, J.J., Schecter, A., Masuda, Y., Kikuchi, M., 1987. Comparison of PCDDs and PCDFs in the tissues of Yusho patients with those from the general population in Japan and China. Chemosphere 16, 2017-2025. 

CDD/CDF body burdens, elimination half-lives corrected for alterations in body weight ranged from 3.5 years for 1,2,3,4,6,7,8-HpCDF to 7.9 years for 2,3,7,8-TCDD and 15 years for 1,2,3,4,7,8-HxCDD (Rohde et al. 1997). In the same study, half-lives for elimination due only to fecal excretion ranged from 10 years for OCDD to 22 years for 2,3,7,8-TCDD and 27 years for 1,2,3,7,8-PeCDD. The half-lives for 2,3,4,7,8-PeCDF in humans exposed to contaminated rice oil in the Yusho incident range from 2 to 30 years, and were inversely dependent on adipose tissue concentrations above approximately 10 ng/kg body weight (i.e., the higher the body burden, the faster the elimination) (Ryan et al. 1993a). 

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). 

No studies were located regarding dermal effects in humans exposed specifically to CDDs by the oral route. Evidence from human case reports in the Yusho/Yu-Cheng incidents (which involved exposure to CDFs, PCBs, and CDDs) and from animal studies, however, indicates that dermal effects could occur after exposure by the oral route (ATSDR 1994). 

Ocular Effects. The incidence of eye irritation correlated with the intensity of chloracne in a study of workers employed in a 2,4,5-T factory (Poland et al. 1971), but the role of 2,3,7,8-TCDD, if any, cannot be established. No studies were located regarding ocular effects in humans exposed specifically to CDDs by the oral route. Evidence from the human case reports in the Yusho/Yu-Chcng incidents (which involved exposure to CDFs, PCBs, and less so CDDs) and from animal studies, however, indicates that ocular effects could occur after exposure by the oral route (ATSDR 1994). Ocular effects observed in... 

Iida T, Hirakawa H, Matsueda T, et al. 1991. [Therapeutic trial for promotion of fecal excretion of PCDFs and PCBs by the adminstration of cholestyramine in Yusho patients] Fukuoka Ishi 82 317-325. (Japanese)... 

Miyata H, Takayama K, Ogaki J, et al. 1989. Level of PCDDs, coplanar PCBs and PCDFs in patients with Yusho disease and in Yusho oil. Chemosphere 18 407-416. 

Murai K, Tsuji H, Fujishima F. 1991. [Treatment of Yusho PCB poisioning patients with cholestyramine.] Fukuoka Ishi 82 226-329. (Japanese)... 

Rappe C, Nygren M, Buser H, et al. 1983. Identification of polychlorinated dioxins (PCDDs) and dibenzofurans (PCDFs) in human samples, occupational exposure and Yusho patients. Environ Sci Res 26 241-253. 

Ryan JJ, Gasiewicz TA, Brown Jr JR. 1990. Human body burden of polychlorinated dibenzofiirans associated with toxicity based on the Yusho and Yucheng incidents. Fund Appl Toxicol 15 722-731. 

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