Encyclopedia of Family Medicine

Chapter 8 Environmental Hygiene and Self-Care (2)
major pollutants in the atmosphere
There are many types of air pollutants. According to incomplete statistics, more than 6 million tons of pollutants are discharged into the atmosphere every year around the world.There are more than 100 species that have caused harm or have attracted people's attention. Among them, the ones that have a wide range of influence and pose a great threat to the human environment include: smoke, sulfur dioxide (SO2), carbon monoxide (CO), hydrocarbons (HC), nitrogen dioxide (NO2).Soot and sulfur dioxide are the raw materials and catalysts for sulfuric acid fumes. NO2, CO, and HC form optical smog under the action of sunlight. These secondary pollutants are corrosive and irritating, and HC also contains carcinogens.

The most common pollutants in daily life are:
Soot: Pack of soot and dust.The most common form of smoke is black smoke, which is produced by incomplete combustion.Urban industrial production causes smoke and dust, the exhaust gas and dust raised by motor vehicles running on the road, and the incomplete combustion of coal in the kitchen can produce smoke and dust.The dust in the atmosphere comes from various aspects, and the amount of atmospheric dust in cities is greater than that in rural areas.

Sulfur dioxide and acid rain: Most of the sulfur dioxide in the atmosphere comes from the combustion of fuels such as coal and petroleum, and a small amount is produced in the smelting of metal minerals and the production of sulfuric acid.With the surge in energy consumption, sulfur dioxide emissions are rising worldwide.It is estimated that by the end of the 20th century, the world's sulfur dioxide emissions are estimated to reach about 3.4 million tons.With the increasingly serious atmospheric sulfur dioxide pollution, acid rain is formed through gas-phase and liquid-phase oxidation reactions under suitable meteorological and geographical conditions.

Nitrogen oxides and photochemical smog: Nitrogen oxides are high in cigarette smoke, and are also found in large amounts in exhaust from vehicles and aircraft.

Carbon monoxide: mainly comes from coal burning and automobile exhaust.

Harm of air pollution to human body
The composition of air pollutants is extremely complex, and the characteristics of harmful substances are also very different.The hazards caused by air pollutants include acute poisoning, chronic respiratory diseases, important dysfunction and other system diseases.

Acute poisoning is caused by large-scale industrial pollution or accidental leakage of toxic waste gas from enterprises. So far, there have been many major public hazard incidents recorded in human history.For example, in 1952, in London, England, a large amount of soot dust was released due to household coal burning, which accumulated for a long time in the dense fog and acted synergistically with air pollutants, causing chest tightness, coughing, and vomiting among residents, resulting in 4 deaths in just 4000 days , was shocked for a while.

The most important chronic poisoning caused by air pollution is respiratory diseases, including dry rhinitis, atrophic rhinitis, chronic bronchitis, emphysema, bronchial asthma, pneumoconiosis, lung cancer, etc.There are many carcinogenic and cancer-promoting substances in air pollutants, such as polycyclic aromatic hydrocarbons in automobile exhaust gas; heavy metals such as asbestos, nickel, chromium, beryllium, arsenic in dust; 3-benzopyrene adsorbed on floating dust, etc. .Working and living in such a polluted environment for a long time will significantly increase the incidence of cancer, especially lung cancer.

The problem of acid rain is a hot spot in the world today, and my country is also a country with serious acid rain pollution.Caused by acid rain, tree branches and leaves wither, crops lose their vitality, buildings are corroded and rusted, acid rain increases the acidity of lakes and rivers, fish are poisoned, bone deformed, and their development is hindered to the point where fish eggs cannot hatch and are cut off from offspring, acid rain acidifies soil The soil is barren and the growth of plants is hindered. Acid rain is highly irritating to human skin, eyes and throat. Inhalation of particulate matter adsorbed with sulfuric acid mist can accumulate in the lungs, causing lung tissue sclerosis, pulmonary edema and other diseases.Acid rain not only harms human health, but also threatens human survival due to the destruction of the ecological balance of the environment.

Measures to prevent and control air pollution

Control the sources of air pollution and rationally distribute industries.

Control the discharge of pollutants.A large number of trees and flowers are planted in the environment, which not only beautifies the environment, but also purifies the air.

An adult breathes [-] liters of air every day. In daily life, especially in the family, clean air is very important to people's health.The following list some daily pollution prevention and control measures.

(1) Keep the air in the home clean and fresh: use high-quality anthracite coal as far as possible for domestic coal.The structure of the coal stove should be reasonable, the stove must be equipped with an exhaust chimney, and the doors and windows should be opened frequently in the room to keep the indoor air flowing.Swallowing should be prohibited indoors.

(2) Insist on wet sweeping: Sprinkle water before sweeping to prevent dust from polluting the air.

(3) Do not burn fallen leaves: the smoke from burning leaves pollutes the nearby air.Because some leaves can absorb and accumulate certain harmful substances, plus the dust accumulated on the leaves, when burning, these substances will be discharged into the air with the smoke, and there may also be carcinogens such as 3-benzopyrene, and the leaves will fall quickly. After burning, a large amount of carbon monoxide will be produced.Therefore, when dealing with fallen leaves, don't just burn them for convenience.

(4) Prevent natural hydrogen sulfide and other toxic gases from being poisoned; long-term useless wells, unidentified underground caves, sewage pools, cesspools and other places contain high concentrations of hydrogen sulfide, carbon dioxide and other asphyxiating gases in the local environment, entering this area. The environment should be ventilated and exhausted first, wear a gas mask, and then go to verify the situation to prevent accidents.

(5) Do not run and exercise in the smoke.

Electromagnetic Radiation and Health

Since cosmic rays bombard every corner of the earth's surface, and naturally occurring radioactive elements are everywhere.Human beings are not only exposed to various natural radiation backgrounds all the time, but also have the potential danger of radiation from artificial radioactive pollutants.

Patients who receive excessive X-rays, y-rays or isotopes in the hospital will suffer different degrees of radiation damage.Fetuses are very sensitive to radiation.Pregnant women should try to avoid unnecessary medical radiation.Leukemia and premature aging are considered to be long-term damage caused by electromagnetic radiation exposure.

Tobacco leaves contain radioactive substances such as uranium, radium-226, polonium-210, and lead-210. Smoking is one of the potential causes of bronchial lung cancer.

The X-ray dose generated by the high-voltage power supply of the TV is very weak, but if you do not pay attention to protection for many years, this dose cannot be ignored.The simplest protection is to keep a proper distance between people and the TV when watching TV.Black and white TVs are generally about 2 meters away; X-rays from color TVs are much stronger than black and white TVs, so you must watch TV at a distance of 2 meters from the color TV.

Induction cookers, microwave ovens, refrigerators, washing machines, and vacuum cleaners will bring pollution of electromagnetic waves to modern homes, and electromagnetic waves can permeate the entire space during use.This electronic fog cannot be seen or touched.The human body is disturbed by electromagnetic waves for a long time, memory loss, joint pain and vision loss.

The calcium carbide in lighters is a rare earth chloride product, and the raw materials contain trace amounts of radioactive substances such as uranium and thorium.Most of the fire-breathing toys currently on the market contain calcium carbide, so when using lighters and fire-breathing toys, pay attention to the traces of radioactive substances in the calcium carbide, and wash your hands in time after use.

Harm of vibration to human body
The harm of vibration to the human body can be divided into systemic vibration and local vibration. Vibration is often accompanied by noise, and the two promote each other.

Motion sickness and seasickness caused by various means of transportation are due to systemic vibration, which causes the reflex of the vestibule and internal organs after stimulation.Whole body vibration can be further divided into vertical, horizontal and oscillating vibrations.Mild ones can cause dizziness, vertigo, nausea, vomiting, etc., while severe ones can cause congestion and position movement of internal organs, resulting in a series of adverse effects on the nervous system, cardiovascular, digestive, and reproductive systems.Such as memory loss, reduced work efficiency, indigestion, increased menstruation in women, etc.People with a history of motion sickness (boat) can take anti-sickness drugs before taking the car or boat, which can prevent or reduce the disease.

Local vibration is the long-term vibration of the user's hands and wrists caused by the use of pneumatic tools and electric tools, such as pneumatic hammers and pneumatic drills.Hand vascular neuromotor disorder, manifested as peripheral vasospasm and ischemia.Light numbness and stiffness in the fingers; severe numbness and tingling in the fingers.Those who belong to the occupation need to work in this environment, personal protection should be strengthened to reduce the harm of local vibration, and the rest place of workers should maintain a warm environment.

The harm of dust to human body
Dust can be divided into two categories according to particle size: those with a diameter greater than 10 microns are called falling dust, which are heavy and easy to settle, and those with a diameter of less than 10 microns are called floating dust, which float in the air for a long time in the form of aerosols and cannot be seen by naked eyes.Dust contains a variety of heavy metals and inorganic salts. Floating dust can absorb various toxic substances, some of which are carcinogens.The floating dust adsorbed with toxic substances is like spreading the seeds of cancer, becoming the ghost of harming people, causing trouble everywhere.

The production environment of factories produces dust, cars run on the road to raise dust, and soot from coal burning in homes contains a variety of suspended particles. After people get up in the morning, the concentration of floating dust in the bedroom is 2 to 5 times that of the outdoor. These floating dust come from people Putting on, taking off clothes, laying quilts and the shedding of human dander, it can invade the human body through the respiratory tract, or be deposited in the alveoli.Or absorbed into the blood and lymph, causing potential harm to the human body.

Some families use asbestos materials as interior decoration materials. Asbestos dust particles are fine and can stay indoors for a long time, and invade the human body through the respiratory tract to form asbestosis. A tumor that develops between the chest cavity and the body wall).

The smoke formed indoors by smoking tobacco at home can kill macrophages and lymphocytes in the alveoli and pleura, thereby reducing the body's immunity.

Scientific research shows that the immune damage caused by long-term exposure to harmful smoke and dust is very similar to the aging performance of the human body, that is to say, it makes people age prematurely.

Harm of noise to human body
From the point of view of physics, noise is an irregular and chaotic combination of sounds of different frequencies and different intensities. From a physiological point of view, all annoying, annoying, and unwanted sounds are called noise.Such as the rumbling sound of machines, harsh horns, the whistle of the train, the sound of flushing toilets, loud talking and laughing, etc.

Long-term exposure to a noise environment (above 90 decibels) will cause qualitative lesions of the ear receptors, resulting in hearing loss. If you work in this environment for many years, noise-induced deafness will occur. The greater the noise intensity and the longer the time, the hearing loss caused by the greater the damage.In addition, living in a noisy environment for a long time affects sleep, mental tension, often causes trouble, distraction, neurasthenia syndrome, and gastrointestinal dysfunction.

In life, we should also pay attention to a kind of "infrasonic noise" that cannot be heard by the ear.Generally speaking, the frequency range of the sound that the human ear can hear is 20 Hz to 2 Hz (an object vibrating once per second is 2 Hz). can not hear.Infrasound is a peculiar sound that can penetrate the walls of buildings without significant attenuation and can travel thousands of miles in the atmosphere.Infrasound has many sources and travels far.Storms, typhoons, volcanic eruptions, and earthquakes can all emit infrasound. According to records, the powerful infrasound produced by the eruption of the Niklakato volcano in India in 20 circled the earth three times and stopped after 1883 hours. All recorded this infrasound.High-intensity infrasound can cause symptoms such as dizziness, nausea, stomach pain, insomnia, tinnitus, palpitations, numbness of limbs, irritability, and lack of energy. Extremely strong infrasound can also cause death.At present, many countries have listed infrasound as one of the public hazards of environmental pollution, and many preventive measures have been taken.

Problems caused by pesticide pollution

In order to prevent pests and weeds, pesticides are directly applied to the soil, or the excess part of the crop spraying agent is directly dropped on the ground, and the pesticides floating in the atmosphere fall on the ground through rainfall, which can lead to pesticide pollution of the soil.Because the pollution of soil will inevitably lead to the pollution of crops, the pesticides in the soil are absorbed by the roots of crops, and then distributed to the whole crops through migration and transformation in plants.The edible parts of some crops are under the soil, such as peanuts, potatoes, yams, taro, etc., which are more likely to be polluted by residual pesticides.When people eat food with high pesticide residues for a long time, trace amounts of pesticides can gradually accumulate in the body, which will gradually change the physiological functions of the human body and cause chronic poisoning. This kind of poisoning is slow and the symptoms are not obvious. Potentially dangerous, such as DDT and 666 chronic poisoning mainly manifests as hepatomegaly, degeneration and necrosis of liver cells, accompanied by varying degrees of anemia, leukocytosis and central nervous system lesions.

At home, attention should be paid to the handling of pesticide-contaminated or potentially contaminated food. Careful rice washing is beneficial to remove pesticide residues.Appropriate cooking methods have a certain effect on the removal of pesticide residues in food. For example, cooking rice with a pressure cooker can improve the removal of pesticides, and cooking with an electric rice cooker can eliminate more than 50% of 666 residues.

For the pesticides sprinkled on fruits and vegetables, most of them are on the surface of leaves and peels. Generally speaking, it is easier to clean. Vegetables can be soaked in water for some time, and then carefully washed; fruits can be washed with Clean with detergent such as detergent, then rinse with clean water, then peel and shell for consumption.For example, for DDT on tomatoes, after careful cleaning with the above method, the removal rate of pesticide residues can reach more than 90%. Some families love to eat raw and cold salad dishes, and the cleaning of vegetables is more strict, and it is forbidden to be careless.

Trace Elements and the Environment

According to the content of elements in the human body, they can be divided into macro elements and trace elements. The former accounts for 99.95% of the total weight of the human body, including carbon, hydrogen, oxygen, sulfur, calcium, phosphorus, etc., which constitute the components of various tissues in the body and maintain Cell function, trace elements account for 0% of the total body weight.Although they account for a small proportion in the human body, they have a vital impact on human physiological functions, metabolism, biological genetics, etc., and this impact is directly related to the environment in which people live. Therefore, the environment—trace elements— — There is a very close relationship between the three of human health.

At present, it is confirmed that the trace elements necessary for the human body are: iron, fluorine, zinc, strontium, iodine, selenium, copper, vanadium, chromium, manganese, molybdenum, cobalt and more than ten kinds.They have special physiological functions in the human body, such as iron is an important component of heme, cobalt is indispensable for vitamin B12, more than 90% of vanadium in the human body is accumulated in adipose tissue, it has an important function of inhibiting cholesterol biosynthesis, many enzymes It contains copper, zinc, manganese, molybdenum and other elements, and the specific physiological activity of enzymes is controlled by these trace elements.

The physiological functions of trace elements in the human body not only need to maintain an appropriate content, but also maintain a dynamic balance with the external environment in which people live.Some trace elements in nature are absorbed and enriched by plants and animals, and then enter the human body through the food chain, and some directly enter the human body. The human body absorbs a certain amount of essential trace elements according to physiological needs, and excretes the rest. Trace elements in the environment, with the change of time and space, re-enter the human body through the medium of the atmosphere, soil, water body, and food chain. some kind of balance.If the environment is polluted and there are too many or too few trace elements in the environment, the proportion of trace elements in the human body will be out of balance, and the balance of body functions will be destroyed, resulting in various consequences that endanger human health.

Causes and prevention of endemic diseases

The composition and abundance of life elements in the human body is the result of human evolution, heredity and variation under the long-term action of environmental factors. There is a certain appropriate range of trace elements that the human body needs to complete various functions. Normal growth and development and maintenance of health.If a certain element is too much, not enough or the proportion is abnormal, it can cause imbalance of the body's regulating system and even endemic diseases.

Due to the lack of elements, it can cause endemic goiter, endemic cretinism and so on.

Too many elements, endemic fluorosis, endemic arsenic poisoning, endemic selenium poisoning and so on.

Since the 70s, the endemic diseases that the country has focused on preventing and controlling include endemic fluorosis, endemic goiter, endemic cretinism, Kashin-Beck disease, and Keshan disease.

Endemic goiter and endemic cretinism are diseases caused by environmental iodine deficiency.Adequate iodine supplementation before or during early pregnancy can prevent endemic cretinism.Sufficient iodine supplementation at various developmental stages after birth can prevent and treat endemic goiter.Iodine supplementation measures include adding iodine to salt.

The etiology of Kashin-Beck disease and Keshan disease is not yet clear, but after the application of selenium supplementation, the condition of Kashin-Beck disease has been significantly reduced, which can promote the repair of bone scale changes and prevent deterioration.

For elemental excess endemics, limit the entry of excess elements in the environment into the organism.Coastal residents eat too much seafood with high iodine content; or inland residents drink water with high iodine content, which can cause endemic goiter epidemic, and excessive intake of iodine should be limited at this time.Endemic fluorosis is caused by excessive fluoride content in drinking water, and drinking water should be taken to remove fluoride.

Precautions when traveling
When traveling, whether by car, boat or plane, the car, boat and plane are all in motion and are affected by noise, vibration, waves, air currents, etc., and the space occupied by each person is limited, so it is easy to cause fatigue or fatigue. Dizziness, vomiting.People who have experienced motion sickness, seasickness, or airsickness should take sedatives such as Haining half an hour before the bus ride, lie down on the bus with eyes closed, don’t look at the shaking scenery outside the window, don’t look down at writing, and don’t eat greasy food , and not too full.

(End of this chapter)