In the chemistry experiment courses in middle school, there are many experiments that require alcohol lamp heating, all of which are inseparable from a special experimental tool, asbestos net .
After all, asbestos mesh has good thermal insulation and can disperse the heat of the alcohol lamp flame to every corner of the bottom of the container to make it evenly heated.
Asbestos network
But little do you know that is such an object that brings great convenience to chemical experiments, and its potential harm cannot be underestimated.
The asbestos component in the asbestos net turns out to be a type of carcinogen . Research data from shows that the global death toll caused by asbestos exposure is even as high as 230,000 per year.
Classic carcinogen asbestos
So, since that is the case, why has asbestos not been banned yet?
The carcinogen hidden beside us - asbestos
Speaking of which, you may not believe that Asbestos , a carcinogen, is actually hidden around us in large quantities.
In addition to the asbestos net mentioned by Dachuan at the beginning, also has some fabrics, building materials, etc. for fireproof purposes, among which the materials used for fireproof and heat insulation are basically asbestos.
Asbestos cloth
Especially among building materials, asbestos is the most common substance.
Some cement tiles, wall panels, decorative boards . In order to play a fire-proof role, a large amount of asbestos will be added during the production process.
Asbestos tiles that are often used to build roofs in rural areas
Not only that, it is almost winter, Some of the heaters we often use in winter . The materials used as heat insulation are basically asbestos.
Asbestos
in the electric heater is also precisely because of this, asbestos is definitely one of the closest carcinogens to us.
How harmful is the ?
Speaking of which, in terms of chemical composition, is not poisonous in itself. It is just a kind of silicate .
Asbestos
But is very harmful in terms of physical properties.
At present, the most commonly used asbestos in in the world is thermos asbestos . asbestos fiber is much thinner than what we see with the naked eye.
kilograms of thermos asbestos contains about 1 million fine fibers , , and the weight of each fiber is only about 0.001 grams, the diameter is only 0.5 microns, and the length is less than 5 microns. Due to its extremely small weight and small body, once the fibres like are released into the environment, they will be suspended in the air like tiny dust particles, making it difficult to fall.
thermos asbestos
In industrial production, 0.01 grams of asbestos fibers will be released for every 1 kilogram of thermos asbestos consumed by . According to , there are about 10 asbestos fibers.
In the industrial production process, the consumption of asbestos is often calculated in tons. In this way, you can think about how many asbestos fibers will be produced in this process.
Asbestos processing plant is piled up in a large number of asbestos cloths
Asbestos fibrils suspended in the air will not only harm people's skin, but also cause some skin diseases. Once is inhaled into the lungs, the harm it brings will be even more serious .
The dust particles in the air are generally granular. Even if they are inhaled into the lungs, they will be "cleaned" by the lungs quickly. To put it bluntly, this is a matter of phlegm.
But asbestos fibrils are different. They are not granular, but needle-shaped . Once inhaled into the lungs, they will pierce the lung tissue, including alveolar , and it is difficult to excrete it out of the body.
Asbestos fibrils
As more and more asbestos fibrils are inhaled, it will further lead to pneumoconiosis and even lung cancer. seriously endangers human health, which is also the most terrifying thing about asbestos.
Previously, researchers have published such a set of research data. In 2016 alone, the global death toll caused by asbestos exposure reached more than 220,000, and in 2017, this number rose to more than 230,000.
As of today, this number is still high... Why don’t
disable asbestos?
I wonder if you have the same question as Dachuan, that is, since the harm of asbestos is so great, why not ban asbestos?
Asbestos
In fact, since , WHO included asbestos on the list of first-class carcinogens in 2017, many countries in the world have completely banned the mining and use of asbestos.
However, given the long history of asbestos mining and its excellent performance, my country does not prohibit the mining and use of asbestos.
Historical data shows that as early as the week 2 period, my country had already started to use asbestos fiber to make fabrics. The fabric made of asbestos was also given a very interesting name - firewashing cloth . The reason is that after this fabric becomes dirty, it will become as white as new as soon as it passes through firewashing (i.e., firewashing).
Firewashing cloth
Of course, the long history of asbestos mining is just a small reason why asbestos cannot be used. The most fundamental reason is actually the excellent performance of asbestos.
Nowadays, asbestos quilts as heat insulation and fireproof material have been applied to almost all aspects of our lives. Although many other materials can also be used as alternatives to asbestos, in comparison, asbestos is still lower in cost and has better performance .
Houses built with asbestos tiles and asbestos wall panels
Putting such a cost-effective material without using it, which is unrealistic...
is written at the end
Of course, does not prohibit the use of asbestos, but it does not mean that asbestos can be abused.
Asbestos
China has very strict standards for the mining and processing of asbestos.
Take the workshop processing standards of asbestos in warm asbestos. my country has clearly stipulated many years ago that the threshold limit of asbestos in the workshop air is fibers/cubic .
Under such strict processing standards, although does not prohibit the use of asbestos in my country, the disease caused by asbestos exposure is limited to a very low state.
Asbestos processing
But then again, Asbestos is a type of carcinogen . If we can find reliable alternative materials in the future, the ban on asbestos will definitely be put on the agenda.
But before this, all the friends here must be vigilant. When comes into contact with asbestos products, try to take protective measures to prevent being damaged by asbestos...
