A turn of the circle of friends only to find that the people of the Imperial City today are eating "set meal", originally March haze, April flotsam is enough to make people suffer, did not think that the May farewell has been a long time sandstorm is back, Dr. Clove in the "Tianjie Xiaoyu Run as Crisp" Hangzhou really for the Imperial City partners sweat!

To answer the question, let's first introduce two types of particulate matter: PM 2.5 and PM 10.

PM 2.5 is the abbreviation of "particulate matter", meaning "fine particulate matter"; "2.5" refers to 2.5 microns, PM 2.5 refers to particulate matter in the atmosphere with a diameter of less than or equal to 2.5 microns, which is less than 1/20th of the thickness of a human hair.

PM10 refers to respirable particles in the atmosphere with a diameter of less than or equal to 10 micrometers. From the definition, it can be seen that PM2.5 is in fact a kind of PM10, and they are in a relationship of inclusion and inclusion, with PM2.5 generally accounting for about 70% of PM10.

1, the main culprit of hazy weather is PM2.5

Because they are particularly small, these particles can ignore the protective barriers of the respiratory tract and enter and attach themselves directly to the trachea, bronchial tubes, and can even reach the alveoli.

They irritate the respiratory system and induce infections or immune responses.Causes bronchitis, pneumoniaetc. Patients with asthma，Air pollution, on the other hand, canCauses asthma to worsen.. Patients with underlying diseases such as hypertension and coronary heart disease, air pollution canIncreased risk of cardiovascular and cerebrovascular disease.. In patients with lung cancer and chronic diseases of the heart and lungs, haze canIncreased risk of death。

At the end of 2013, the International Agency for Research on Cancer (IARC) under the World Health Organization (WHO), after collating more than 1,000 relevant research reports from five continents, came to the conclusion that "air pollution is carcinogenic", and at the same time explicitly classified airborne particulate matter (including PM2.5) as a class of carcinogens.

2. Compared to haze, the main components of dust storms are soil and yellow sand

Dust particles in the soil mainly elevate the airborne PM 10, which enters the upper respiratory tract but is partially eliminated through sputum, etc., and is also blocked by the lint in the nasal cavity.

Many people may think that the particles in haze are smaller while those in dust storms are larger. But in fact, it is not possible to make such a simple comparison. In fact, PM 2.5 is also found in sandstorms, while PM 10 is also found in haze.

3. In the final analysis.The difference between a haze and a dust storm is the winds

Usually in calm weather, air convection and diffusion conditions are extremely poor, allowing pollutants to accumulate and not disperse, when haze is likely to occur. That's why everyone is "waiting for the wind" in hazy weather.

Dust storms often occur in windy weather, gusts of wind wrapped in yellow sand, which rises because of the wind, the wind stops then stop, come and go in a hurry. So everyone is looking forward to the wind.

4. Is it useful to bring a simple mask to deal with dust storms?

According to Dr. Clove, first of all, if you go out, a mask is a must! As I just said, there is also PM2.5 in sandstorms, so it's best to be fully armed and wear a better mask or gas mask if you can. Whether dealing with sandstorms or haze, we can not be taken lightly.

In addition, like severe haze, dust storms and such extreme weather, it is best for everyone to stay at home, prepare enough food, minimize going out, close the doors and windows tightly, and put the air purifier on full power for the best!

To understand the hazards of dust storms and haze on the human body, we first need to understand the "particulate matter" in the air into the human body after the destination.

The aerodynamic size of particles determines their deposition in the respiratory tract: those below 10 μm enter the nasal cavity, those below 7 μm enter the pharynx, and those below 2.5 μm penetrate deep into the alveoli and are deposited into the blood circulation.

PM2.5, which we often refer to during air pollution, is particulate matter with an aerodynamic diameter of less than 2.5 μm, also known as lung-enterable particulate matter. Compared with coarse atmospheric particles, PM2.5 has a smaller particle size and stronger penetrating power, which can reach the walls of fine bronchial tubes and interfere with gas exchange in the lungs. Because of its large surface area, it is more likely to adsorb toxic and harmful substances, such as heavy metals and toxic microorganisms.

The composition of PM2.5 is very complex, and the currently known chemical composition of PM2.5 includes inorganic components, organic components, trace heavy metal elements, elemental carbon, etc.. The inorganic component mainly contains sulfate, nitrate, ammonia salts, etc.; the organic component includes polycyclic aromatic hydrocarbons (PAHs), etc.; and trace heavy metals such as chromium, manganese, copper, zinc, lead and nickel. Dust is also a component of PM2.5.

Dust storms, as a climatic hazard phenomenon, refer to sandy weather phenomena with visibility less than one kilometer caused by strong winds swirling up sand on the ground. As the name suggests, dust storms include both fine solid gravel and smaller diameter dust, while the dynamics of dust particles span a wide range of sizes, including not only PM10 particles but also PM2.5 particles.

When the PM2.5 concentration is the same (e.g. PM2.5 = 500 μm/m³), the amount of nitrogen oxides, sulfur compounds, and organic compounds in the PM2.5 heavy pollution caused by sandstorms is less than that in the PM2.5 bursts caused by man-made factors, such as heavy industrial emissions, and the resulting damage to the human body is slightly lighter.

However, it should be noted that because PM2.5 stays in the atmosphere for a long time and spreads over a wide range of distances, and dust storms themselves have the characteristics of cross-regional long-distance transmission, therefore, dust storms originating from Xinjiang, Inner Mongolia or Mongolia, etc., when passing through the coal-rich regions such as Shanxi, Shaanxi and Inner Mongolia and finally arriving at Beijing, Shanghai and other regions, their components have already entrained a large amount of coal-burning along the way and other anthropogenic pollutants generated by industrial emissions, which also include a large amount of heavy metal substances. The components of the dust storms, when they pass through coal-rich areas such as Shanxi, Shaanxi and Inner Mongolia, and finally arrive at Beijing and Shanghai, have already contained a large amount of anthropogenic pollutants from coal combustion and other industrial emissions along the way, including a large amount of heavy metals.

Prof. Pan Xiaochuan of Peking University School of Public Health said - ""The heavy metals and other toxic and harmful substances carried by dust storms include mercury, lead, cadmium, fluorine, sulfur, etc., and many of these substances are coal combustion pollutants. Although the amount of these heavy metals is slight, one characteristic of heavy metals is bioaccumulation, they are not easily discharged after entering the body, so they will keep accumulating in the body, and when they reach a certain amount, they may develop illnesses."

Therefore, although PM2.5 caused by sandstorms may be slightly less harmful to the human body than PM2.5 burst caused by purely anthropogenic emissions under the same level of pollution intensity, the sandstorms themselves contain a certain amount of various types of toxic and hazardous substances, which, after entering the bloodstream with respiration, may also cause cardiovascular and cerebrovascular diseases, respiratory system and other diseases.

Without reasonable protection, both sandstorms and haze can be hazardous to human health. In the sandstorm weather, we should treat the usual haze weather as protection - minimize going out, indoors need to turn on the air purifier and regular replacement of the filter; such as the need to go out, it is necessary to wear PM2.5 outdoor professional protective masks, and return to the indoor in a timely manner after the cleaning of the mouth and nose.

Sandstorms and haze are fundamentally different, dust storms are meteorological disasters in which the dust raised from the ground is the main particulate matter, of which the particulate matter component is mainly silica, while the haze is mainly air pollution produced in the process of industrial and agricultural production, of which the particulate matter component is carbon black as the core, attached to a variety of organic compounds and microorganisms.

There is a difference between the two diameters, as we all know, the damage of particles to the body and lungs and the diameter of particles has a very big relationship, the larger the diameter of the particles the less likely to reach the depths of the lungs, it is easy to be blocked in the upper respiratory tract and the large airways, and by the phlegm adherence to coughing up outside the body, coughed up may not be phagocytosed by the macrophage and fixation, which is one of the reasons for the formation of nodules in the lungs, if the long term in the dusty environment and do not pay attention to protection, there is a risk of the formation of dusty lungs. If you work for a long time in a sandy and dusty environment and do not pay attention to protection, there is a risk of forming pneumoconiosis. Haze is the main particle diameter of PM2.5, most of the particles can reach the depth of the lungs and enter the alveoli, and some of the toxic and harmful organic substances may be deposited in the alveoli and terminal bronchioles and have a far-reaching impact on the local area. These organic substances can directly damage the immune barrier of alveoli, resulting in a low level of immunity locally, and most of the pathogens attached to the surface of the PM2.5 can easily grow locally and grow locally in the damaged alveoli. Most PM2.5 surfaces have pathogens attached, which can easily grow locally in the damaged alveoli and form foci of infection, which is the cause of acute exacerbation of many lung diseases caused by particulate matter.

From the way of damage, the damage of sand and dust to the alveoli is mainly physical damage, and the small amount of organic matter attached to its surface is not enough to cause serious damage to the alveoli and bronchioles, but the long-term deposition of a large number of particulate matter can also form serious damage such as pneumoconiosis nodules, PM2.5 is mainly chemical damage, the toxin may damage the genes of the cells, resulting in genetic damage, which may affect the cellular protein expression, resulting in abnormal function, and even the possibility of carcinogenicity. PM2.5 is mainly a chemical damage, the toxicants may damage the genes of the cells, causing genetic damage and affecting the protein expression of the cells, resulting in abnormal function and even the possibility of carcinogenicity. More seriously, PM2.5 may enter the phagocytes and then enter the bloodstream to be transferred all over the body, and some people have found evidence of the existence of PM2.5 in the central brain nervous system.

Both dust and haze have an effect on the human body, but haze is relatively more frequent and more damaging to urban life and is a significant threat to respiratory disease.

Haze is more harmful than dust storms. Hazelong-lastingYou can't breathe natural fresh air, and PM2.5 particles can invade your body and cause harm. When a dust storm hits, you can avoid it by closing the windows or staying in your car, and you can still breathe natural air during the storm, and the dust storm is very short-lived.

People think I answered correctly, please give me a like. I am a practicing lawyer, long-term attention to social issues, there are legal, social and other issues you can follow my headline! Invite me to answer legal questions more often, thank you!

All are very big, all need to be managed, all need to be involved in everyone. Sandstorms compared to the duration of a short period of time, but the intensity of the killing force is obvious, the haze lasts a long time wide range of indoor and outdoor is not easy to dissolve, is a slow knife to cut the meat more harmful!

Too long not to read the version:

It is true that dust storms were considered less of a health threat than haze in the past.

In recent years, however, theDust storms are moving toward a "particulate matter deluxe package," and the health threat is not necessarily less than haze。

Detailed version:

There are a few key aspects to determining which is the greater health hazard, the dust storm or the haze:

Size of particulate matter

This subject also mentioned thatThe smaller the particulate matter, the easier it is to penetrate deeper into the human body, and the greater the health threat to the human body。

For example, PM10 (respirable particulate matter) can be blocked by the nose and throat, while PM2.5 (fine particulate matter) can enter the alveoli, and PM0.1 (ultrafine particulate matter) can even enter the nervous system.

In the past, we usually think that the particles in dust storms are larger, mainly PM10; while the particles in haze are smaller, mainly PM2.5.

However, the widespread dust storm that hit the north of China on May 4 this year refreshed past perceptions.

In this dust storm, Beijing's PM10 concentration, in the southeast and southwest once soared to more than 2,000 μg/m3; and PM2.5 is also not willing to lag behind, breaking through 600 μg/m3.

PM10 and PM2.5 at the same time soaring high, can be called "particulate matter luxury package".

Although it is true that in this dust storm, the concentration of PM10 is higher than that of PM2.5, but such a high concentration of PM2.5, even if it is put aside in the haze, it is still serious pollution, and it can be said that there is less PM2.5 in the dust storm?

Concentration of particulate matter

This is easy to understand, too.The higher the concentration of particulate matter, the more particulate matter the human body inhales, and the greater the health threat。

In the same vein as the previous article, the concentration of PM2.5 in dust storms is now comparable to severe haze.

Composition of particulate matter and its adsorption

The particulate matter itself has a complex chemical composition, including sulfate, nitrate, carbon, heavy metals, organic matter, etc., which are harmful to health in their own right; at the same time, other toxic and harmful substances are adsorbed on the particulate matter, including heavy metals and organics, which aggravate the harm to health.

For example: sulfates and nitrates damage the respiratory and cardiovascular systems; polycyclic aromatic hydrocarbons (PAHs) cause cancer, birth defects, damage to genetic material, etc.; while Pb causes anemia, damages the nervous system and the brain; and Mn and Cd damage the nerves and kidneys.

In conclusion.The smaller the particulate matter, the more likely it is to carry these toxic and harmful substances and deposit them deep within the body, causing irreversible damage.

The vast majority of particulate matter in the haze is caused by the combustion of fossil-based energy sources (e.g., oil, coal, etc.) and industrial emissions, which are also known asanthropogenic sourceIt's certainly more toxic thannatural sources(e.g., naturally occurring dust, soil dust, etc.) is much larger.

In comparison.The proportion of natural sources is much higher in dust storms。

That dust storm on May 4 this year, according to satellite monitoring, originated mainly in the western deserts of Inner Mongolia, meaning that the initial source of the sand mass was of natural origin.

True-color map of May 3 dust monitoring, with dust in gray

But.Sand clusters can also carry pollutants and particulate matter emitted by human activities as they enter areas of high human activity.。

In the March 2002 Beijing sandstorm, mineral aerosols were wrapped up in roadside and local pollutants over a long distance, resulting in concentrations of pollutants up to 10 times the usual level, which will continue to contaminate water bodies and soils after settling, and may enter into agricultural products along the biological chain.

Overall.Nowadays, dust storms are also mixed with high concentrations of PM2.5, which is rich in toxic and harmful substances, and it is not necessarily less than that in haze. In this case, it is difficult to say that sandstorms are less harmful than haze.

defend

Protection is also needed if you are caught in a dust storm:

1. Minimize going outside, keep windows and doors closed indoors, and preferably turn on your air-cleaning equipment.
   

2. If you have to go out, be sure to wear a mask that filters PM2.5.
   

3. Children, the elderly and sensitive people with respiratory and cardiovascular diseases need extra care.

I think the haze is more harmful to the body, first of all, sandstorms blowing over, the air stays short, a moment to scrape away, while the haze is able to stay in the air for several days. Furthermore, haze is a long time accumulation of airborne filth, containing sulfur and other elements harmful to the body more than sandstorms.

Depends on what things, for the human body, the harm of the haze has to be greater, because it will breathe into people's lungs leading to some diseases; and for the natural environment, he will self-purification, injuries are not injured on that. Sandstorms, people can avoid the harm to the human body as long as they do a good job of protection, but nature can not, some places to come to a sandstorm to reduce some of the available land, into the Gobi Desert. So are not good, the main harm to people is the haze, the main harm to the environment is the sandstorm.

Haze is the most harmful, a long-term accompanied by the city, the second is toxic, the elderly and children are more likely to be damaged, and dust storms in the harm belongs to the natural behavior, can be controlled, the number of times, can be avoided.

Should the haze be more harmful to the human body, there are more harmful substances in the air than when the air is fresh, and once the human body inhales these harmful substances, it is certainly harmful to health. If the haze days are prolonged, old and weak people will get sick. Haze is a major challenge to the human respiratory system. And although sandstorms are also severe weather phenomena, the particles in haze are much smaller than those in sandstorms in the same severe weather conditions, making them more harmful than sandstorms.