The cause and harm of smog 50 words

Among the 50 words, people usually use words such as fog, haze and haze to describe the weather conditions when the air humidity is high and visibility is low. Then, the following 50 words are about the causes and harm of smog.

The cause and harm of smog 50 words What is smog?

Haze is mainly caused by air pollution. It is a light yellow or black fog, and it is a polluted mixture, which is mainly formed by tiny particles in the atmosphere and ground ozone. Smog causes difficulty in breathing and has a negative impact on human health.

How is the smog formed?

Smoke is formed by pollutants or gases released when fuel is burned. When sunlight and its heat come into contact with these gases and tiny particles, smoke will be formed. It is purely caused by air pollution. The complex photochemical reaction between volatile organic compounds, sulfur dioxide and nitrogen oxides releases the ground ozone layer and tiny particles into the air. These harmful compounds are pollutants released by the combustion of motor vehicle gasoline and diesel oil, which are directly discharged into the air by factories and various human heating activities.

Smog is often caused by traffic congestion, high temperature, sunshine and no wind. These are also several factors that lead to air pollution. In winter, when the wind speed is low, it is easier to form smog, which increases the degree of air pollution that people breathe on the ground. It not only affects vision, but also damages the environment.

The formation of smog is directly related to temperature. Inversion is a phenomenon that warm air stays near the ground instead of rising. If there is no wind during the inversion period, the smog will stay for many days. Of course, smog will be more serious because of pollution release. This is because the smog produced by pollutants released by traffic congestion through photochemical reactions is the mainstream. Smog not only affects big cities, but also appears in suburbs and rural areas.

Hazards of smog

The harm of smog is obvious. It is harmful to humans, animals and plants. Many deaths are related to bronchial diseases. Severe smog will greatly reduce ultraviolet rays and indirectly lead to a decrease in the secretion of vitamin D, thus becoming one of the reasons why some people suffer from rickets.

When a city or town is shrouded in smog, people will feel it immediately. Smog can cause inflammation of eyes, inflammation of lung tissue, chest tightness and pain. In addition, smog can easily induce diseases such as colds and pneumonia. Long-term exposure to smog can also induce lung diseases, even fatal diseases such as lung cancer.

A small amount of exposure to smoke has the risk of inducing asthma attacks. Therefore, asthma patients should avoid contact with smog. Haze can also lead to premature death and gather to dangerous levels in densely populated areas. The people most affected by smog include the elderly, children and patients with heart and respiratory diseases.

Ground ozone in smog can also inhibit plant growth and cause damage to crops. Crops and vegetables such as soybeans, wheat, potatoes, peanuts and cotton have all been affected by smog. Smog threatens the environment, killing many animals and green life, because they need time to get used to breathing and live in a toxic environment.

In short, smog is a devastating problem, especially when harmful chemicals form smog due to rapid modernization or industrialization. This is why governments all over the world are taking measures to reduce pollution emissions.

The causes and hazards of smog are 50 words, and two cause haze weather.

The similarity between fog and haze is sight distance obstacle. However, the reasons and conditions for the formation of fog and haze are quite different. Fog is a large number of tiny water droplets or ice crystals floating in the air, and the formation conditions should have a high water vapor saturation coefficient. When fog appears, the relative humidity of air often reaches 100% or approaches 100%. With the daily change of air humidity, fog is more common or thicker in the morning and evening, and it becomes lighter or even disappears during the day. The effective horizontal visibility is less than 1KM in fog. When the effective horizontal visibility is 1- 10km, it is called light fog.

There is actually a difference between "fog" and "haze". Fog refers to the weather phenomenon that the visibility is lower than 1 km due to the condensation of suspended water vapor in the atmosphere; The formation of smog is mainly the result of a large number of suspended particles in the air and meteorological conditions. There are three reasons:

In the horizontal direction, the phenomenon of static wind increases. The higher the buildings are built in the city, the obstruction and friction of airflow passing through the urban area will be obviously weakened. The increase of static wind phenomenon is not conducive to the diffusion and dilution of suspended particles in the atmosphere, and it is easy to accumulate around urban areas and suburbs;

There is an inversion in the vertical direction. The inversion layer is like a pot cover over a city. This inversion phenomenon that the upper air temperature is higher than the lower air temperature limits the vertical movement of the lower air, making it difficult for suspended particles in the air to drift to the upper air and be blocked at the lower air and near the ground.

The increase of suspended particles in the air. With the growth of urban population and industrial development, the number of motor vehicles has soared, resulting in a large increase in pollutant emissions and suspended solids, which directly leads to a decline in visibility.

In fact, dust "smog" will also occur in home decoration, and indoor dust is pervasive, which is not only harmful to the health of staff and users, but also increases the cleaning burden. When the dust is serious, it will bring more hidden dangers to the decoration project!

Is the formation of smog weather the cause of automobile exhaust emissions? Smog, the car is not the culprit, but it does produce smog, at least the car has to bear part of the responsibility.

In fact, it can be seen from the 9.3 parade blue that only the government makes up its mind that blue sky and white clouds are not dreams! However, if China's economy is to develop and its society is to progress, the process of industrialization cannot be stopped. Therefore, large coal-fired boilers or coal-to-gas projects will not stagnate, and smog will still exist. The economic and social environment is actually a contradiction. You can't have your cake and eat it.

What diseases can be caused by the harm of haze weather?

1, smog can lead to asthma recurrence.

It is foggy in autumn and winter, so the elderly must pay attention to protection in morning exercise to avoid the recurrence of asthma. The fog and wind are small, the air flows slowly, and there are many impurities in the air, which will cause asthma!

2. Smog can easily cause tracheitis.

Tracheitis is inflammation caused by virus or bacterial infection, physical and chemical stimulation or allergic reaction, which often occurs in cold season or when the temperature suddenly changes.

3, smog is easy to cause cerebral hemorrhage.

When the fog comes, the air pressure is low, pollutants in all directions are difficult to disappear, and people can easily feel chest tightness, especially toxic substances such as acid, amine and benzene and pathogenic microorganisms, which will cause cerebral hemorrhage!

4. Smog can lead to high blood pressure.

Haze weather is a health killer for patients with cardiovascular diseases, and it does have an impact on patients with cardiovascular diseases such as hypertension. When fog enters the human body, it will consume nutrients and cause internal injuries.

5, smog can lead to conjunctivitis.

Air pollution, smoke, inappropriate contact lenses, irritating gases and chemicals can cause conjunctival inflammation, which may involve one or both eyes. In foggy days, conjunctiva is easy to be infected.

6, smog is easy to cause pharyngitis.

The air pollution is serious in foggy days. If you go out for activities, it is easy to cause chronic pharyngitis, especially some high-intensity activities such as running. Pharyngitis is inflammation of pharyngeal mucosa and submucosal tissue!

Be vigilant: people who are vulnerable to smog weather should strengthen their protection!

PM2.5 pollution exists not only in haze weather, but also in fog and normal weather. Of course, this situation is rare in southern China. When smog weather occurs, it will have an impact on human health, and with the different pollution levels, the scope and degree of affected people are also different. When the pollution is light, it will first have a slight impact on susceptible people, patients with respiratory diseases and cardiovascular diseases, children and the elderly. With the aggravation of dense fog, pollutants are also increasing, which will further aggravate the symptoms of susceptible people, the number of outpatient visits and emergency treatment will increase, and the symptoms of patients with respiratory diseases will also increase. If pollution continues to increase, it will affect the whole population.

From the perspective of prevention, susceptible people should try to reduce outdoor activities, while normal people should reduce physical exercise and heavy outdoor activities. When the smog is serious, susceptible people should avoid traveling. If they have to go out, they can take protective measures, such as wearing masks.

What mask should I wear in foggy days?

The concentration of PM2.5 is very high in foggy days, so wearing a mask is effective in reducing PM2.5 exposure. Obviously, different types of masks have different blocking effects on PM2.5 Generally speaking, occupational dust masks are better than ordinary masks. Studies have shown that the average particle size of occupational dust masks (such as n95 and kn90) is 50nm, which can represent the smaller particle size of PM2.5, and the blocking efficiency is above 97%: the blocking efficiency of special masks for riding is 55% ~ 85%; The blocking efficiency of medical surgical masks is about 80%; The barrier efficiency of cotton handkerchief or square towel is about 30%.

Another study shows that wearing a mask when the pollution level of PM2.5 in the atmosphere is high can not only effectively protect the cardiovascular system of healthy people, but also prevent the symptoms of patients with cardiovascular diseases from getting worse and worse.

It should be reminded that people who are weak, especially those with heart and lung diseases, should consult a doctor before wearing occupational dust masks. Gauze masks can be used repeatedly, but they must be disinfected. Disposable masks such as n95 should not be used repeatedly to avoid secondary pollution.

Is the PM2.5 detector on the market useful for smog detection?

The answer is yes. Yes! But not every PM2.5 detector has a good guiding role. Air radio may be a professional product for smog detection in the industry at present, which can measure PM2.5, carbon dioxide, VOC, temperature and humidity to meet the needs of home air detection. Products with good sales ranking on Taobao are not necessarily excellent products in the industry. At present, only 2-3 products on the market have reliable performance.

How to choose a good PM2.5 detector?

When choosing, look at the following points:

What is the principle of the core sensor used in 1.PM2.5 detector? The detector made of laser principle PM2.5 sensor has good stability and reliability, while the detector made of general infrared principle PM2.5 sensor has poor performance.

Second, we must look at manufacturers and brands and choose good products. Product design and core manufacturing capability are its basic guarantee. We must choose products with core sensing technology, big brands and big manufacturers, especially products of listed companies or large-scale companies, to ensure better quality.

Third, choose a product with interactive experience, a PM2.5 detector, which not only tests, but also spreads love, can interact with people, give people heartfelt experience and care, and let more people share information and happiness in life! Therefore, a good PM2.5 detector has WIFI function, which can interact with the mobile APP through the network, and can transmit the data to the cloud for sharing, so that more people can understand the current situation of air quality.

Fourth, look at the user's evaluation and sales service. A good product, whether it is brand reputation or product sales service, is first-class.

50 words The causes and harm of smog 3 How to prevent smog

1, go out less

Reducing going out is the most effective way to protect yourself. According to the epidemiological study on PM2.5 published by Huang Wei, a researcher at the Frontier Interdisciplinary Research Center of Environment and Health in Peking University, in American Epidemiology 20 12, after excluding the influencing factors such as age, sex, aging and meteorological factors, when the concentration of PM2.5 increases 103 μ g/m3, the risk of excess death from all causes of residents will increase by 2.29%. The risk of excess death caused by cardiovascular and cerebrovascular diseases is higher, which is 3.08%. If you have to go out, don't ride a bike, avoid the rush hour of traffic jam and the section where you often drive, in case you inhale more chemicals. It is also best not to drive a private car, but to take public transportation to contribute to reducing PM2.5

Step 2 wear a mask when you go out

3. Do a good job in personal hygiene

Wash your face, rinse your mouth and clean your nasal cavity in time after going out to prevent the harm of PM2.5 to human body. It is best to use warm water when washing your face, which is beneficial to wash off the particles on your face. When cleaning the nasal cavity, you can repeatedly clean it with a clean cotton swab dipped in water, or repeatedly absorb water with your nose to blow your nose quickly and prevent coughing. In addition to face cleaning, bare parts of the body should also be cleaned.

4. Open the window less in foggy days

Experts suggest that in foggy weather, try not to open the window. If you really need to open the window for ventilation, you should try to avoid the morning and evening smog peak hours, and open the window for ventilation for half an hour to one hour at a time. At the same time, residents who use air conditioning for heating should pay attention to opening windows to ensure adequate indoor oxygen. You can plant a variety of green plants on your balcony, terrace and indoors, such as green crown-leaf plants such as green radish, evergreen and tiger orchid, because of their large leaves and strong adsorption capacity. You can also use an air purifier. 80% of air purifiers in the market mainly purify fine particles in the air, which has a good adsorption effect on PM2.5, but you should pay attention to changing the filter element frequently when using it.

5. Eat lightly and drink plenty of water

The diet in foggy days should choose light and digestible foods rich in vitamins, drink plenty of water and eat more fresh vegetables and fruits, which can not only supplement various vitamins and inorganic salts, but also play a role in moistening the lungs, resolving phlegm, relieving cough, strengthening the spleen and tonifying the kidney. Eat less irritating food and eat more pears, loquats, oranges, oranges and other foods.

6, the right amount of vitamin D.

It's foggy and sunny this season. Due to insufficient ultraviolet radiation and insufficient vitamin D in the human body, some people will experience mental laziness and depression. If necessary, you can add some vitamin D.

7. smoke less

Cigars, cigars and pipes will produce a large number of fine particles belonging to the category of PM2.5 if they are not completely burned. Tobacco smoke contains more than 7000 compounds, including 69 carcinogens and 172 harmful substances, which will seriously harm the health of smokers themselves and those who inhale second-hand smoke. In this smoggy weather, it is even worse. Therefore, smokers should try to smoke as little as possible whether they go out or stay indoors in recent days.