1963 after minamata, a large number of suicide cats and dogs appeared in Niigata prefecture, Japan. 1973, Minamata disease occurred again in Youming Town and other places along the southern coast of Youming Sea. According to reports, there are more than 900 people in these three cases. In fact, the number of victims in Japan far exceeds this figure, and there are about 6.5438+0 million victims in Minamata alone. Scientific experiments have confirmed that the safe concentration of mercury in human blood is 1 microgram/10ml. When it reaches 5- 10 μ g/10 ml, obvious poisoning symptoms will appear. According to calculation, if a person eats 200 grams of mercury every day, 0? 5 mg/kg fish, the amount of mercury ingested by human body is just within this safe range. However, the mercury content of seafood in Minamata Bay is as high as tens of milligrams per kilogram, which has greatly exceeded the standard. In addition, people have to match other foods every day, and these foods may also contain a certain amount of mercury, so the total intake of the whole day is far higher than the safe limit standard.
Minamata disease is a direct public hazard to the marine environment caused by mercury pollution. If pregnant women eat seafood contaminated with methylmercury, it may lead to congenital Minamata disease, and even the offspring of some healthy people (who may be slightly injured and have no obvious symptoms) will not escape bad luck. Many children with congenital Minamata disease have motor and language disorders, and their symptoms are similar to polio, which shows that it is not easy to eliminate the influence of Minamata disease. Therefore, environmental scientists believe that heavy metal pollution in sediments is a "time bomb" in the environment, which may lead to premature explosion when external conditions adapt. For example, under anoxic conditions, some anaerobic organisms can methylate inorganic metals. Especially in the past 20 years, the uncontrolled discharge of a large number of pollutants has made the adsorption capacity of some harbor and coastal sediments saturated, which may detonate this chemical pollution "time bomb" at any time.
2. Cadmium rice and the "pain" incident: 1955- 1972, also known as osteopathy, was another public nuisance disease in Japan in the 1960s. On the Toyama Plain in central Japan, there is a beautiful river called prodigy Chuan. The prodigy Chuanhe River is clear and beautiful, and people on both sides of the strait have lived here for generations, leading the prodigy Chuanhe River to irrigate farmland. This is one of the rice producing areas in Japan. Who would have thought that disaster would befall the people here? 1952 found that a large number of fish died in the prodigy Chuanhe River, and pieces of dead seedlings appeared in the rice fields on both sides of the river. People don't realize that this is a precursor to disaster. From 65438 to 0955, a strange disease appeared in some areas along Shentongchuan. At first, people only felt pain in joints such as waist, back and knees after work, but they can get better after rest or bathing. However, a few years later, the pain spread to the whole body, people's normal activities were restricted, and even when they gasped, they felt unbearable pain. People's bones begin to soften, their bodies shrink and their bones are severely deformed. In severe cases, some slight activity or cough can lead to fractures. In the end, the patient could not eat or drink water, was bedridden, had difficulty breathing and was in great pain, and finally died in extreme pain. The occurrence and spread of this strange disease has aroused people's extreme panic, but no one knows what disease it is, so they can only keep shouting "pain, pain!" " And call it a painful disease. Over the years, more than 280 patients have been found on both sides of Shentongchuan, of which 34 have died and the living patients are still struggling.
So, what is the cause of this disease? Only after investigation did we know the truth. It turned out that in the early Meiji period in Japan, Mitsui Metal Mining Company discovered a lead-zinc mine in the upper reaches of Shentongchuan and built a lead-zinc mine there. Lead-zinc mine also contains a metal called cadmium. After cadmium enters the human body, it mainly accumulates in the kidney, causing damage to the kidney and inhibiting the activity of vitamin D, which is an indispensable nutrient for the human body. Lack of vitamin D will hinder the normal deposition and storage of calcium and phosphorus in human bones, and eventually lead to osteomalacia. When washing ore in this factory, a large amount of cadmium-containing wastewater was directly discharged into Shentongchuan, which seriously polluted the river water. The rice fields on both sides of the river are irrigated with this polluted river water, and toxic cadmium is bioaccumulated, so the cadmium content of rice produced is high. People eat this kind of rice polluted by cadmium for many years and drink the water of Shentongchuan polluted by cadmium. Over time, it has caused chronic cadmium poisoning, and pain is actually a typical chronic cadmium poisoning. Painful diseases occur not only in Japan, but also in other countries. For example, in some areas of China and Guangxi, people once suffered from painful diseases. So far, there is no specific treatment for painful diseases, and there is no safe and effective way to eliminate cadmium accumulated in the body. Therefore, it is particularly important to eliminate the impact of cadmium pollution on the environment, which is the fundamental measure to prevent the occurrence of pain.
Pain is due to the pollution of cadmium to human living environment, which has a wide impact and many victims, so it is recognized as a "public nuisance disease".
3. Scapharca subcrenata and the epidemic situation of hepatitis A in Shanghai: 1988 1 This is a typical "public nuisance" event in which pathogenic microorganisms pollute water bodies, pollute aquatic products and then infect people. 1988,65438+10, 18 On this day, at Tangjiawan Hospital in Shanghai, the largest number of patients came. A day later, the number rose rapidly, faster than the doctor imagined. Take Tangjiawan Hospital as an example. From June 5438+1October 65438+September, a large number of people visited hospitals in Shanghai, most of which were accompanied by typical symptoms such as fever, vomiting, anorexia, fatigue and yellow complexion. In the next few days, the number of patients in Shanghai rose sharply:
198865438+1October 18 43 cases198865438+1October 19 134 cases10.
This disease, later proved to be acute viral hepatitis A, referred to as hepatitis A, is an infectious disease spread through daily contact. In the next short month, more than 300,000 people in Shanghai were infected with hepatitis A, most of them were young adults, of whom 1 1 died. For a time, people "talk about liver discoloration." Through clinical investigation, doctors found that most patients with hepatitis A had eaten Scapharca subcrenata before onset. Previously, there were small-scale hepatitis A outbreaks caused by raw Meretrix meretrix in 1979, 1983, 1986, Shanghai, Ningbo and other places. Is this outbreak of hepatitis A caused by Scapharca subcrenata? In order to confirm the pathogenicity of Scapharca subcrenata, Professor Yu, former dean of the School of Public Health of Shanghai Medical University, led the researchers to Qidong, Jiangsu, the birthplace of Scapharca subcrenata. Soon, they found the hepatitis A virus in the clam, and confirmed that the clam was the chief culprit of hepatitis A with direct evidence.
Scapharca subcrenata is a kind of shellfish that lives in the sediments of estuaries and bays, and has always been a delicacy on the table of Shanghainese. At that time, 50 cents could buy 1 kg of fresh clams. Every year around the Spring Festival, in Shanghai vegetable market, Scapharca subcrenata is always welcomed by housewives. Before 1988, all the Scapharca subcrenata supplied in Shanghai market came from the sea near Weifang, Shandong. However, at the end of 1987, a bumper harvest of Scapharca subcrenata in Qidong, Jiangsu Province, which is adjacent to Shanghai, suddenly occupied the huge market of Shanghai. These places originally did not produce clams, but only conch. In June1987+1October 65438, people discovered the Scapharca subcrenata belt, which has great reserves. So at that time, many ships came to collect them and transported them to various places, including Shanghai, collectively and individually through various channels.
However, no one thought that the little Scapharca subcrenata was in great danger. At that time, the environment of Qidong sea area was polluted by a large number of human and animal feces, and the clam with strong adsorption gathered hepatitis A virus in its own body. Experiments show that clams with shells can't completely kill hepatitis A virus even if they are cooked for 45 minutes. Shanghai people's habit of eating raw food makes it easy for viruses to enter the digestive tract. Coupled with the crowded living environment in Shanghai at that time, the virus spread faster. At that time, people often used faucets because of poor living conditions. Because hepatitis A is transmitted through the digestive tract, that is, the disease enters from the mouth. Because everyone touched the tap and didn't wash their hands before meals, it spread quickly, resulting in almost every family having hepatitis A patients.
4. Riverside Pollution in cancer villages In recent years, some places have blindly emphasized the development of economy, GDP and environmental protection, introduced enterprises that have been eliminated or rejected by some developed countries or regions and seriously polluted the environment, and built chemical plants and pesticide plant that seriously threatened the environment in important water sources and above cities. Some unscrupulous business owners even illegally discharge untreated toxic waste gas and wastewater without conscience, polluting the nearby air, rivers and soil.
1? There are 3,265 people in Shangba Village, wengyuan county City, Guangdong Province. These diseases are esophageal cancer, gastric cancer and liver cancer.
Environment: Since the mining of Dabaoshan Mine, a large amount of washing wastewater containing heavy metals such as cadmium, lead and chromium has been discharged into Hengshi River flowing through Shangba Village without any treatment. Without effective treatment, the surface soil of the mine was completely oxidized and produced 207 kilograms of concentrated sulfuric acid per ton, and a large number of heavy metals were lost with the soil, polluting the water body. No organisms were found in the Hengshi River 1500m channel, and the ecosystem in the downstream 50km water area has not been restored.
The daily intake of cadmium by villagers through diet is only 178 micrograms, which is 3? Six times. Since the early 1980s, 2 10 people in this village have died of cancer, and the incidence of cancer is more than 9 times the national average.
2? There are 726 households with 247 1 person in Maggie Huang village, shenqiu county. These diseases are esophageal cancer, gastric cancer, intestinal cancer, liver cancer and lung cancer.
Environment: The industrial sewage and domestic sewage from Zhengzhou, Kaifeng, Luohe, Xuchang and Zhoukou are all discharged into Shaying River, and the black and smelly river water flows into Maggie Huang Village, and the fish and shrimp in its main canals and cesspits gradually disappear.
The prevalence of cancer in villagers is obviously high, and cancer deaths are increasing year by year. During the period of 14, 105 people died of cancer in the village, accounting for 5 1 of the total number of deaths. 5%, the age of death is mostly around 50 years old, and the youngest is only 1 year.
3? North Laoguanzui Village, Xun County, Henan Province 1274 people. These diseases are esophageal cancer, gastric cancer, lymphoma, lung cancer, liver cancer, uterine cancer and intestinal cancer.
Environment: The village is located along the Weihe River. Paper-making enterprises in the upper reaches of Weihe River have reached Xinxiang City 142, Jiaozuo City, 60 and hua county City 17. Most of them are small businesses. Some industrial wastewater discharged is not up to standard, and some have no sewage purification equipment at all, which leads to serious pollution of Weihe River. The pollution load caused by these enterprises accounts for more than 80% of the local area. The Weihe River flowing through Beilaoguanzui Village is dark red with a layer of foam floating on its surface. 100 meters away, you can smell a strange smell, mixed with foul smell. When the weather is hot, the whole village stinks. The well water in the villagers' home is turbid, with black and yellow particles floating and pungent smell.
10 years, 1 12 people died of cancer, accounting for 90% of the total number of deaths in the village. More than 50% of cancer deaths are under 50 years old. Because of the long-term use of sewage to irrigate the land, the alkalinity of the land increases and the grain output decreases. The pigs raised by villagers can only grow to more than 50 kilograms, and most of them have hoof rot.
4? There are eight "cancer villages" along the Red River in Xiping County. Diseases: laryngeal cancer, lung cancer, liver cancer, gastric cancer, etc.
Environment: The Honghe River flows through Ludian Town, and it is polluted to be inferior to five categories of water quality. About 4000m upstream of the polluted river is a paper-making enterprise in Wugang City, and about 1500m upstream of the polluted river is a cement limited liability company in Wuyang County. Another paper mill in Wuyang County also discharges pollutants into the river. The well water 30 meters deep in the villagers' homes still smells fishy. There are bubbles like soap bubbles when cooking, and you can only drink them after filtering and boiling. The multiple of nitrite and nitrogen in drinking water here is 54? More than five times.
10 years, 8 villages 1838 people died, with an average annual mortality rate of 9? 7%, far higher than the national mortality rate; Moreover, the mortality rate is increasing year by year, and the mortality rate in 2005 was as high as 12? 2%。 The age of the deceased is concentrated between 45 and 70. Villagers along the river used river water to irrigate farmland, resulting in large-scale death of crops such as tobacco leaves, wheat and corn. Every year, more than 50,000 mu of crops in this township suffer from water pollution, resulting in direct economic losses of more than 6.5438+million yuan.
5? Xiditou Town, Liukuaizhuang Village and Xiditou Village, Beichen District, Tianjin. Diseases: lung cancer, gastric cancer, etc.
Environment: It used to be a well-known land of fish and rice. Now there are more than 90 chemical plants around the two villages, such as chemical preparations, dye intermediates, paints and coatings, pesticides and veterinary drugs, flavors and fragrances. These chemical plants produce around the clock, producing black smoke, sewage, odor and noise. In particular, toxic and harmful chemical wastewater is directly transferred from the factory to the river near the village, and the sewage pipe is buried in the vegetable field, so that the water storage canals originally used for irrigation on both sides of the large vegetable field are all filled with red, black and yellow chemical residues. The indexes such as volatile phenol, fluoride and total number of bacteria in local water sources are unqualified, among which volatile phenol and fluoride are toxic substances; The atmospheric emission and odor concentration of chemical plants were randomly selected to exceed the standard 12 times.
Among the 190 villagers surveyed, 148 people have headaches and nausea all the year round, and 39 people often suffer from respiratory diseases such as asthma and tracheitis. In recent years, more than 200 people in the two villages have died of cancer, most of which are lung cancer. High-density waste water and waste gas discharged from chemical plants leads to nothing growing on the ground, and the air is filled with dust and stench. Villagers do not buy radishes, cabbages and fruits because of pollution.
6? Xiaojiadian Village, Feicheng City, Shandong Province. Diseases: gastric cancer, esophageal cancer, liver cancer.
Environment: Dawen River passes through Xiaojiadian Village, and some counties and cities in the upper reaches concentrate on papermaking, printing and dyeing, chemicals, machinery, metallurgy, mining, steel, electricity, brewing, food processing, textiles, pesticides and coal. Feicheng, where Xiaojiadian Village is located, is also focusing on coal mining, coking, paper making and wine making. However, these enterprises discharged pollutants into Dawen River, causing serious pollution of the river. The water quality of many river sections is the worst five kinds of pollution all the year round, among which nitrite, a strong carcinogen, seriously exceeds the standard and manganese exceeds the standard by 57 times. Soil and vegetables are polluted by highly toxic elements, and the chromium content in wheat exceeds the standard 1? 7 times, the lead content in Chinese cabbage exceeded the standard by 2 times, the cadmium content in spinach exceeded the standard by 9 times, the chromium content exceeded the standard by 12 times, the cadmium content in lettuce leaves exceeded the standard by 2 times and the chromium content exceeded the standard by 4 times. In four years, 56 people died of cancer.
7? There are nearly 2,000 people in wuli village, Nanyang Town, Xiaoshan City, Zhejiang Province. These diseases are esophageal cancer, liver cancer, gastric cancer, lung cancer, breast cancer, pancreatic cancer and hematological tumors.
Environment: Since 1992, 26 chemical enterprises have settled in Nanyang Town, discharging pollutants unscrupulously, making the wuli village River black, fish and shrimp extinct, and most of the wells abandoned.
In a few years, more than 70 people died of cancer, accounting for 80% of the deaths in the village, and the incidence of cancer was ten times higher than that in the whole province.