Decreased air quality is dangerous to the health of urban residents.
Decreased air quality is dangerous to the health of urban residents.
the share of urban population was 38.6%. Multimillion-dollar cities (megacities) (New York, London, Tokyo, etc.) are appearing and growing, and their number, size, and problems are increasing.
The process of urbanization also manifested itself in Ukraine. Until 1918, the country was agrarian and 18% of the population lived in cities.
Intensive urbanization in Ukraine began in 1926-1939, when the course was set for the industrialization of the national economy, ie in just 13 years the urban population increased 2.4 times. During 1940-1970, the urban population in Ukraine grew at a much slower pace, because in 30 years it increased only 1.9 times. Since the mid-50s of XX century. a new stage of intensive growth of the number of cities and urban population in Ukraine has begun. In just 30 years, the share of urban population in Ukraine has increased 2.2 times and to at the end of the twentieth century. about 70% of the total population.
In terms of the number of large cities (with a population of over 100,000), our country now occupies one of the leading places among the countries of the world, such cities now – 61. In Ukraine there are 7 cities with a population exceeding or reaching almost a million people:, Odessa, Donetsk, Kharkiv, Zaporizhia and Kryvyi Rih. By the way, the last 30 years of Kyiv have been characterized by extremely intensive demographic development: its population has grown almost 2.5 times and reached 2,600,000 in 2000.
Urbanization cannot be considered without connection with the development of social production, in particular heavy industry, energy, chemical industry, etc. Along with the growth of industrial potential, the creation of new industries in large cities, the population is growing.
Modern large cities are the centers of concentration of diversified industry, an extensive transport network in densely populated residential areas. Moreover, the most important source of urban population growth has been and still is the migration of rural residents to cities. It accounts for more than half of the urban population growth in Ukraine.
The modern city gives its inhabitants many advantages of economic, social and subjective nature, namely:
availability of jobs and the possibility of changing jobs; concentration of scientific and cultural institutions; providing highly qualified medical care; opportunity to create better living and social living conditions; development of international and regional culture.
Despite the benefits of urban life, the urban environment for people is artificial and detached from the natural, the one in which their lives have passed for millennia. The artificial urban environment has a detrimental effect on public health due to air pollution, shortages of sunlight, water, as well as stressors caused by the hectic pace of life, overcrowding, lack of greenery and more. Also, the danger to human health in the city are noise, vibration, transport problems, exposure to electric, magnetic, ionizing fields.
Thus, in a large city, all aspects of human life are exacerbated: the supply of sufficient food and drinking water, control and prevention of air pollution, water resources, soils, disposal and disposal of accumulated hazardous industrial and household waste, as well as antisocial problems associated with a sharp decrease in free "vital" space, the growth of cities in height, the increase in diseases caused by pollution and others.
Let’s identify the main dangers of life in an urban environment.
Urban air pollution. The main sources of air pollution in the city are transport, energy systems of the city and industry.
The bulk of vehicles are concentrated in cities. This is freight, own and public transport. Motor transport accounts for 70% of all toxic emissions. More than 1 million trucks and about 3 million cars are registered in Ukraine. The share of motor transport pollution in the total number of them is in Uzhgorod – 91%, Yalta, Poltava – 88%, Lviv – 79%, Kiev – 75%.
Recently, the volume of carbon oxides, hydrocarbons, nitrogen oxides, and soot has increased in the city air. But the greatest danger in addition to nitrogen oxides are sulfur and lead compounds, their content in urban air has increased significantly. Cities are not adapted to such a large number of vehicles. The length of the run without stops between traffic lights is only 400-600 m, as a result of which the average speed during the day in the city center (in particular, Kiev) and on major roads is reduced to 12-20 km / h, which increases fuel consumption by 3-4 times. Emissions increase accordingly.
Motor transport also leads to specific forms of air pollution. When driving, the tires wear out, and thousands of tons of rubber in the form of dust fall into the air. Urban road transport not only pollutes the air with fuel combustion products, it increases the flow of lead into the environment. In Ukraine, lead is still used with a lead content of 0.36 g / l, while in England, Germany and the United States – 0.013-0.15.
Cities are the main consumers of energy. The city consumes energy in various forms. Fossil fuels are widely used – coal, petroleum products and natural gas. This in itself determines the pollution of cities with combustion products. Energy enters residential buildings and industrial premises in the form of electricity, gas and steam heating.
Decreased air quality is dangerous to the health of urban residents. A person consumes an average of 25 kg of air per day. Even if the relative content of pollutants in the air is insignificant, their total amount that enters the human body during respiration can be toxic. The most common harmful impurity in the air is carbon monoxide. Excessive amounts of this gas in the air leads to rapid fatigue, headache, dizziness, memory loss, impaired cardiovascular and other body systems.
Pollution of urban premises. The specifics of living in the city leads to the fact that people spend 80-95% of their time indoors (houses, subways, offices). One of the indicators of the quality of urban life is indoor air. The US Environmental Protection Agency estimates that indoor air is 100 times more polluted than outdoor air.
Toxic materials of premises – oil paints and solvents, carpet glue, furniture varnish from which benzene, toluene and other substances are allocated.
Measures to improve indoor air quality:
effective remedy against toxins – houseplants; instead of air fresheners use vinegar, pouring it into a plate and putting for 1-2 hours in the room; in closed small rooms (refrigerators, toilets) put an open box of baking soda; make a fresh branch of spruce or pine in the room; use baking soda or borax instead of bleach; do regular wet cleaning, as well as ventilation; equip the kitchen with a fume cupboard; do not leave bottles of detergents and disinfectants open.
Causes of indoor air pollution:
pollution from burning wood, coal in fireplaces; unventilated gases from gas stoves and water heaters; aerosols; cleaners that contain chlorine or ammonia; varnish and wax floor coverings; humidifiers; insect sprays (insecticides); cigarette smoke.
Pollution of drinking water in cities. Drinking water is the most important factor in human health. Drinking water enters the taps of city apartments from rivers, reservoirs, lakes, and underground depths. The purest – groundwater (especially deep, artesian) water. But for large cities, this water is not enough.
According to the WHO, water can contain 13,000 toxic substances, water transmits up to 80% of all diseases, from which 25 million people die each year worldwide.
In real conditions, water contains organic and mineral compounds, micro- and macroelements, gases, colloidal particles and living microorganisms. The main components of drinking water are unchanged – bicarbonate, sulfate and salts of calcium, magnesium and sodium. Of the minerals in the water are silicon, fluorine, strontium, zinc, of the macronutrients – iron and potassium. The content of these substances should not exceed the MPC.
Soil particles and anything that can rot adds organic compounds to the water. their diversity is huge,
To make natural water suitable for consumption, it undergoes several stages of purification and disinfection at water supply stations. Methods of purification of polluted water can be combined into the following groups:
mechanical; physical; physical and mechanical; chemical; physico-chemical; biological; complex.
After mechanical, chemical and physico-chemical methods of treatment, wastewater is subject to biological treatment (microorganisms) for the final treatment of effluents from organic matter. Biological treatment is carried out in biofilters, in aeration tanks, in biotankers, etc.
After certain methods of purification, various viruses and bacteria can be found in water (dysentery bacteria, Vibrio https://123helpme.me/buy-compare-and-contrast-essay/ cholerae, pathogens of typhoid fever, polio virus, hepatitis virus, etc.). There are four ways to neutralize the remaining microorganisms:
thermal (boil); using strong oxidants (eg, chlorine, ozone, potassium permanganate); exposure to precious metal ions (usually silver); physical methods (using ultraviolet rays or ultrasound).
The problem of providing the population of Ukraine with quality drinking water is becoming more complicated every year. There is a situation when almost all surface, and in some regions, groundwater in terms of pollution does not meet the requirements of the standard for water supply sources. Drinking water is becoming an active factor in the harmful effects on health and the root causes of many dangerous mass infectious diseases, including viral hepatitis A.
Due to chlorination in drinking water, organochlorine compounds are formed, for example, the amount of chloroform exceeds 1.5-2 times the norm recommended by the WHO. In addition, other toxic substances can get into drinking water: heavy metal ions, phosphorus and sulfur compounds, pesticides, nitrates, nitrites. The insufficient efficiency of the existing water treatment technology is evidenced by the high incidence of intestinal infections.