All aspects of safe drinking water
Drinking water safety actually involves a wide range, including water source, water supply plant facilities, water supply pipe network and so on. These links involve water conservancy departments, environmental protection departments and construction departments.
Today, I will mainly talk about health management at work. In 2007, we conducted a national supervision and inspection of drinking water. From this supervision and inspection, the main problems are the design of water supply facilities and the management of water plants. The main outstanding problems are some self-built water plants and secondary water supply facilities.
In terms of design, it is mainly because the design conditions of some self-built water plants are relatively simple, and only one reservoir is set up, such as purification, sedimentation and filtration of municipal water plants, which most self-built water plants do not have. The water tank for secondary water supply is relatively old. At present, many cement tanks are used as water tanks, or some cement tanks are coated with a layer of waterproof paint, which is toxic and will penetrate into the water after a long time.
The facility design is unreasonable. At present, the reservoirs of self-built water plants in some places are located near garbage dumps or sewage pipes, causing sewage leakage and affecting the water quality in the reservoirs.
In addition, we generally arrange water supply network and non-water supply network in parallel. If this kind of pipeline is used for a long time, there may be some corrosion and leakage, and some sewage will leak into the drinking water pipe network, so it will also cause some water pollution.
So this is a matter of facilities and design. Another problem is management. According to the requirements of current laws and regulations, on the one hand, personnel are required to hold certificates and pass physical examination. Managers should not have infectious diseases, and water supply units should also have management systems. For example, the reservoir should be treated regularly and the water should be disinfected. There are many management loopholes at present.
Regarding cleaning, a survey was conducted in Kunming in 2005. There are about 1 1800 secondary water supply tanks in Kunming. In 2005, there were more than 6,000, so half of the secondary water supply tanks were cleaned and half were not cleaned. Through investigation, we know that 1/3 reservoir has not been cleaned for a long time, and some even have not been cleaned for one year, which will cause pollution of secondary water supply.
Moreover, we conducted a survey on drinking water pollution in 2005, and the accidents caused by secondary water supply accounted for 20% to 30% in 2004-05.
Drinking water pollution is harmful to health in several aspects. One is that it will cause the epidemic of infectious diseases. At present, there are 37 legal infectious diseases in China, of which 8 are water-borne infectious diseases, which can be spread by drinking water. There are also some carcinogens, such as nitrate in drinking water or bottled water, which have been heated by the media a while ago, because some international public opinion believes that some carcinogens will cause cancer if they are too high in water for a long time.
There are also toxic diseases, such as arsenic, fluorine, lead and mercury. If the content of drinking water is too high, it may cause arsenic poisoning, fluorosis, lead poisoning and mercury poisoning, all of which are possible. There are many health problems related to drinking water.
At present, we don't have much data about the health effects of drinking water. Since the promulgation of the Law on the Prevention and Control of Infectious Diseases, the state has detected infectious diseases, and detailed data have been obtained in recent years. I can tell you that since 2007, more than 1 120000 kinds of infectious diseases have been reported, and infectious diseases such as cholera, typhoid fever and dysentery account for 23% of all infectious diseases.
So you can see that some are infected by water, and some diseases are caused by eating unclean food.
So at present, our statistics can't tell which ones are caused by food and which ones are caused by drinking water. So this is the focus of our next work, and we are also doing this work, that is, monitoring drinking water diseases, that is, who and how many people are caused by drinking water.
Now the international community attaches great importance to this issue. Not long ago, the World Health Organization also reported that about110 diseases in the world are caused by drinking water, and in underdeveloped countries, the proportion of many children dying from diseases is also quite high.
It was introduced to African countries, and the death caused by water quality accounted for about 8%, the most serious being Angola, accounting for 24%. Therefore, both China and the whole international community are very concerned about drinking water.
Refer to the above? China Net-All aspects of safe water use