What is Yusho Disease?

Yushō disease (literally “oil symptoms”) was a massive polychlorinated biphenyl (PCB) poisoning that occurred in northern Kyūshū, Japan, in 1968. In January 1968, rice bran nuts oil produced by the Kanemi company in Kyushu was contaminated with PCBs. And polychlorinated dibenzofurans (PCDF) during production. For deodorization, the oil heat using PCB as the heating medium, flowing through pipes. Due to the holes in the lines, the PCBs seeped into the rice bran oil.

The contaminated rice bran oil was then sold to poultry farmers for use as a feed supplement and to consumers for cooking. From February to March 1968, farmers began to report that their poultry was dying due to apparent difficulty breathing; a total of 400,000 birds died. Some 14,000 people who consumed contaminated rice oil were affect in Japan. More than 500 died. Additionally, in children, cases of poor cognitive development report.

Although a decade has passed, an almost similar case occurred in Taiwan in 1979. Once again, the rice oil had heat from leaking pipes. At this time, the disease was known there as Yu-cheng disease (Chinese: 油症; pinyin: yóuzhèng; Wade–Giles: Yu2 cheng4). Similar symptoms and effects of PCBs and PCDFs show, especially in children.

Symptoms of Yusho Disease

The main symptoms of Yusho disease were breakouts in the form of acne, pigmentation of the skin, nails, and conjunctiva, increased discharge from the eyes, and numbness of the extremities.

What was the Cause of Yusho’s Disease?

Yusho is an intoxication caused by rice oil contaminants with polychlorinated biphenyls.

What are the effects of PCBs on human health?

What are the effects of PCBs on human health?

Polychlorinated biphenyls are a collection of 209 different substances that share a standard structure but vary in the number of chlorine attache. The international agreement on persistent organic pollutants, draft by 122 nations in Johannesburg in December 2000, highlighted PCBs as one of the “dirty dozen” chemicals to phase out worldwide. It estimates that General Electric dump 1.3 million pounds of various types of PCBs into the Hudson Stream from 1946 to 1977, which remains banner.

PCBs are a Probable Human Chemical

The International Agency for Research on Growth and the Environmental Protection Agency classify PCBs as probable human carcinogens. The National Toxicology Package conclude that PCBs are reasonably likely to cause human cancer. The National Organisation for Work-relate Safety and Health determined that PCBs are a potential occupational carcinogen.

Studies of PCBs in humans have shown increased rates of melanoma, liver cancer, gallbladder cancer, bile duct cancer, gastrointestinal tract cancer, and brain cancer, which may link to breast cancer. PCBs cause various cancers in rats, mice, and other study animals.

Acute Toxic Effects

People directly exposed to high levels of PCBs, either through the skin, by consumption, or in the air, experienced irritation of the nose and lungs, pelt irritations such as severe acne (chloracne) and rashes, and eye problems.

PCBs have Developing Effects.

Women exposed to PCBs before or throughout pregnancy can give birth to children with important motor control and neurological problems, including reduced IQ and poor short-term memory.

It discovered that a group of children in Michigan whose mothers had been exposed to PCBs had lower birth weights and smaller head sizes. Lower performance on standardized memory, psychomotor, and behavioural tests, and a lower IQ.

These effects lasted for at least seven years. A group of women occupationally uncovered to PCBs in upstate New York had shorter pregnancies and gave birth to low birth weight babies. Another study involved the children of women who had eaten contaminated fish from Lake Ontario. If found significant performance deficiencies on a standardized behavioural assessment test.

Exposure of rats to a form of PCBs caused growth retardation and delayed puberty, and the treatment decreased sperm count and genital malformations. In other studies, PCB exposure to rats in utero caused behavioural and psychomotor effects that last into adulthood.


In summary, our study provides complete data on Yusho patients with 50 years of follow-up. It is that the mortality risk ascribable to all cancer and lung cancer. It increased significantly among males compared with the general population. Furthermore, the SMRs for liver cancer increases considerably among females.

Our findings suggest carcinogenic risk to humans after exposure to PCBs and PCDFs. It remains higher among Yusho patients, and the importance of care engagement and optimum management in controlling the burden of Yusho disease. There is no consistent knowledge about the effects of PCB and PCDF exposure on several. Is it a type of cancer and non-cancer-relate disease, and does further longer-term investigation warrant it?