Will putting toilet blocks in the toilet pollute the water and cause cancer？ In fact, it is a new biography of old ballads.

　　People’s Daily Online, Beijing, April 20 (Xiao Jinbo, Wang Yajing) Recently, there was another rumor on the Internet that "the domestic water supply system is not suitable for putting toilet blocks in toilets, and polluted water will flow back into the tap water system, causing cancer and leukemia …" In fact, this is an old rumor that is biased. As early as 2015, some media have refuted this rumor.

　　The hot news on the Internet said, "The water supply company strongly appeals to the general public not to put blue toilet cleaning blocks into the water tank of their toilets, which will harm others and themselves. The toilet cleaning blocks are only suitable for buildings with dual water supply systems abroad, and there is almost no such water supply system in China. Because there is no one-way check valve for the main valve and sub-valve, under the negative pressure, polluted water with strong carcinogenicity and disease will flow back into the water supply system, which will cause cancer, leukemia and so on.

　　In 2015, Life Times interviewed relevant experts on this statement and reported it under the title "The Truth: Toilet Cleaning Blocks Cause Cancer". The reporter interviewed Liang Li, spokesperson of Beijing Water Supply Group, and Li Hongzhu and Liang Li, associate researchers of Tianjin Institute of Medicine, and said that the water tank of the toilet used in residents’ toilets is sewage. When water is cut off or users concentrate a lot of water, the pressure in the tap water pipe decreases.At this time, if the water injection valve in the toilet tank is damaged or the rubber ring at the water inlet is not tightly sealed, the blue water will flow back into the tap water pipeline. This happens only occasionally. Under normal circumstances, the water in the toilet tank does not flow into the water supply pipe.If you are worried about the backflow of the toilet water tank at home, you can change the water inlet mode of the water tank to the upper water inlet; If the tap water discharged at home is found to be blue, it can be discharged by discharging water. Under normal circumstances, the amount of water in the toilet tank is not very large, and it can be used after the color of the water returns to normal by discharging water.

　　At the same time, Liang Li also pointed out that the water used for flushing toilets in some communities is "reclaimed water" (that is, non-drinking water that is treated with urban sewage or domestic sewage to reach a certain water quality standard and reused in a certain range), which is separated from the tap water pipeline. Therefore, there is no possibility of sewage flowing back to the toilet tank of such families to pollute drinking water, so there is no need to worry.

　　Regarding the problem of "toilet block causing cancer", Li Hongzhu said that there is still a lack of exact research data, and its toxic effect on the human body is related to the dose, so don’t be too nervous.

　　The main components of toilet block are surfactants or binders such as alkyl sulfonate and polyvinyl alcohol, which are commonly used in cleaning products such as soap and belong to external use. If ingested for a long time, it may cause chronic poisoning. It is suggested that families with single water supply system should try not to put toilet cleaning blocks in the water tank, and can choose bottled toilet cleaning liquid for cleaning.

　　Guangzhou Daily in 2016, "Backward flow of toilet water? Is the toilet block carcinogenic? Rumors! In the manuscript, the relevant person in charge of Guangzhou Water Supply Company said,Under normal circumstances, the toilet water will not flow back; Even if there is backflow, it can be taken away by letting the water flow naturally for a few minutes after the water supply is restored. There are only one or two cases of backflow of toilet cleaning water in Guangzhou every year.. Chen Yisha, a senior experimenter at the School of Chemistry and Chemical Engineering of Guangzhou University, said,Toilet cleaning water is corrosive, but it is harmless to human body if it is not drunk.

　　In 2015, Guangming Daily’s "Toilet cleaning block causes cancer" has no scientific basis.》In the article, Zhi Xiuyi, Minister of Science Popularization Department of China Anti-Cancer Association, and Chen Wanqing, Deputy Director of National Cancer Prevention and Research Office, both said that,At present, there is no scientific research to prove that toilet cleaning blocks are related to cancer, and there is no clear scientific basis for the statement that toilet cleaning blocks cause cancer.Moreover, the toxicity of any carcinogen must be accumulated to a certain amount before it can cause harm to the human body or cause cancer. The online statement is too exaggerated.

　　Since 2015, there has been a rumor report about "toilet cleaning block causing cancer" every year, but the rumor has revived again and again and continues to spread on the Internet to deceive netizens. The column of "Seeking Truth" reminds us that when encountering similar news, we need to be more suspicious. If we check whether it is an old rumor through online search, the more cautious netizens are, the less rumors will spread. Do not believe in rumors, do not spread rumors, and jointly safeguard the clear network.