Recently, a message spread on the Internet. The gist is that in order to prevent the epidemic, a local neighborhood committee issued chlorine dioxide disinfection tablets to residents, requiring residents to put the tablets into the sewer pipes at home at the same time.
This news has caused a lot of discussion on the Internet, some people say that people will be poisoned, some people say that carcinogens will be generated, and some people say that there is no problem in doing so.
So, does this have a disinfectant effect? Is it safe for residents? Since the emergence of the epidemic, we have been exposed to all kinds of disinfectants, are they any different?
Chlorine dioxide itself is safe and should still be used with caution
Chlorine dioxide, probably because the name has a "chlorine" word, everyone will think that it is related to chlorine, it must be very toxic. Not really.
Chlorine is highly oxidizing, causing viruses or bacteria to inactivate and eventually die, so it is often used in disinfectants. The representative disinfectant is chlorine dioxide and 84 disinfectant (the active ingredients are hypochlorous acid and hypochlorite).
You don't have to worry too much about the safety of chlorine dioxide. The chlorine gas we fear is poisonous because it is a suffocating gas that has difficulty breathing, coughing, and lung damage when inhaled. Chlorine dioxide has a similar effect on the human body, but the effect is not as extreme as chlorine.
In addition, the tap water we drink is usually disinfected with chlorine dioxide.
Therefore, chlorine dioxide itself is relatively safe. However, there are some mistakes in arranging for households to be released together at the same time.
Produces excessive chlorine dioxide
Judging from the pictures circulating on the Internet, the chlorine dioxide disinfection tablets used are a type of preparation similar to effervescent tablets.
Usually, its main components are chlorite and citric acid, which are not easy to react under solid conditions; after encountering water, the disinfection tablet disintegrates, and chlorite forms a large amount of chlorine dioxide under acidic conditions. Most of this chlorine dioxide is soluble in water, and a small part of it evaporates slowly, making it very efficient and safer to disinfect.
Aqueous chlorine dioxide 丨wikimedia commons/Iridos
However, if many people use it at the same time, it is not even ruled out that some people put multiple disinfection tablets at a time in order to disinfect more thoroughly, so that a large amount of chlorine dioxide is suddenly produced in the sewer. These dioxides may no longer evaporate into the air in the form of slow release in dissolved water, but instead spew out excess of strongly oxidizing gases in a short period of time. At this point, the relatively mild chlorine dioxide becomes a source of risk.
If you are unlucky enough to meet a toilet cleaner
In addition, the use of chlorine dioxide disinfection tablets in sewers has another risk that cannot be ruled out: in case someone happens to use toilet cleaners!
The active ingredient in toilet cleaner is hydrochloric acid. When hydrochloric acid comes into contact with chlorite, it produces not only chlorine dioxide, but also highly toxic chlorine gas.
Therefore, although in theory, the use of chlorine dioxide disinfection tablets in water, as long as the method is appropriate and the concentration is appropriate, the actual danger is negligible. However, the real risk remains due to the collective simultaneous use of a large number of disinfectant tablets in the sewers and the lack of organized coordination arrangements. This kind of activity, it is best for professional institutions to quantify the operation according to the actual processing scale, which not only ensures the disinfection effect, but also avoids some unnecessary troubles.
Efficient and highly destructive 84 disinfectant
Let's take a look at 84 disinfectant solution similar to chlorine dioxide.
84 Disinfectant solution because it contains chloride, so the disinfection principle is similar to chlorine dioxide.
Because of the strong oxidation, there is also the effect of bleaching 丨 A certain 84 disinfectant promotional page
This type of disinfectant needs to be diluted and used. When diluting, be sure to pay attention to the concentration (available chlorine content). When disinfecting generally, you can refer to the instructions for the use of disinfectant to wipe and soak related items.
Hypochlorous acid is unstable and easy to decompose, pay attention to the expiration date when using 84; if you use disinfectant tablets with water, remember to "use the spot".
84 disinfectant has a strong irritation, be sure to follow the instructions when using, pay attention to ventilation, do not enter the eyes and contact the mucous membranes. Another side effect is that because they produce chlorine atoms, if used in some metal materials, chlorine atoms will cause long-term corrosion; some equipment involving circuits, such as the shell of mobile phones, computers and other equipment, the use of such disinfectants requires caution.
Also, it must be noted that 84 disinfectant, like chlorine dioxide, cannot be used with toilet cleaners. They undergo a chemical reaction to produce chlorine gas, which not only causes disinfection to fail, but also causes damage to the body due to the toxicity of chlorine gas.
Medical alcohol is the most commonly used and is generally available
Medical alcohol refers specifically to alcohol with a concentration of 75%.
Alcohol denatures proteins and therefore has the effect of killing microorganisms. However, the killing effect of low-concentration alcohol is poor, while high concentration alcohol will make the protein on the surface of microorganisms coagulate too quickly, and alcohol cannot penetrate deep into it, and the effect is poor. Practical studies have found that alcohol with a concentration around 75% has a strong killing effect.
Bacteria and viruses are two different types of organisms, medical alcohol has a strong killing effect on bacteria, but it is not necessarily effective for viruses, and even ineffective for many viruses. The new crown virus can be killed by alcohol because of the protein envelope outside the virus.
Hand sanitizer and "germicidal hand sanitizer"
Frequent hand washing with hand sanitizer or soap and washing hands with running water for more than 20 seconds has a certain effect on the blocking of virus transmission and can be combined with other protective means.
Of all handwashing products, hand sanitizers containing "biocides" are particularly popular. However, like medical alcohol, the fungicides in hand sanitizers may not work well for viruses.
Common hand sanitizers, generally used fungicides (or bacteriostatic agents) are two categories, one is a chlorine-containing phenol, representing the substance is chloro-m-xylenephenol (PCMX); and the other is a quaternary ammonium salt, representing the substance benzalkonium chloride (BAC).
In some scientific tests, both PCMX and BAC can kill some viruses, such as the common influenza virus. However, the concentrations used in the experiment are often higher, and the elimination effect is very related to the type of virus, such as another common virus, HIV, these fungicides are just a joke.
The active ingredients of hand sanitizer and hand sanitation products are more diverse, some are alcohol, some are cetrimonium chloride, hypochlorous acid and so on. They can be used as an alternative to handwashing with running water soaps and when hands are not visibly dirty.
Peracetic acid is cost-effective, but has poor stability
During the SARS epidemic in 2003, many people heard about the prestige of peracetic acid, which became the main force in disinfecting public places.
Peracetic acid has super oxidation properties. Under normal circumstances, peracetic acid only needs to be formulated into an aqueous solution with a concentration of about 0.005%, which can be used for sanitize, and can kill almost all viruses in one minute, which is very efficient.
However, peracetic acid also has a significant disadvantage, that is, poor stability and easy decomposition. As a dangerous good, it is difficult to buy peracetic acid directly on the market, and for most people, it is not realistic to prepare a peracetic acid solution.
Peracetic acid also has a certain degree of corrosiveness, and it is necessary to pay attention to safety when using. However, it will not have a significant impact on all kinds of devices in life.
Physical sanitize methods, need to consider the occasion
In general, there are only two ways to physically sanitize viruses, one is to use light, usually ultraviolet light, and the other is to use heat. The vast majority of viruses are sensitive to ultraviolet light and high temperatures.
Relatively speaking, high temperature disinfection has high operability in the domestic environment, such as some items can be boiled with hot water, and clothes can be washed at the highest temperature indicated on the label.
The sign in the circle indicates that the maximum washing temperature is 40 ° C 丨 Li Xiaokui
UV light is a simple sanitize method, in the laboratory, usually only need to turn on the UV lamp, you can disinfect the countertop.
However, the current household UV lamp equipment is usually not designed for sanitize, and the wavelength of ultraviolet light they emit may not be suitable for sanitize viruses.
Moreover, the side effects of ultraviolet light are very large, it will produce many toxic and harmful substances such as ozone, and may directly cause human harm (electro-optic ophthalmia and dermatitis will appear within 20 minutes of exposure). Therefore, it is not recommended to use UV lamps as a method of home disinfection.
Guokr
In addition to some of the common disinfection methods mentioned above, there are many substances or methods that are also commonly used for virus sanitize. However, because these substances are often dangerous goods, such as ether has flammable and explosive properties, and chloroform, when poorly preserved, can easily produce highly toxic phosgene and cause death, they are difficult to buy and are extremely unpresented for non-professionals.
Author: Sun Yafei
Editors: Luna, Dai Tianyi, Li Xiaokui
An AI
At the time of this article, the author of this article is receiving the Wenjin Book Award... Welcome to read!
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