Download Лекция 3

The impact of air pollution on human health
The contribution of environmental pollution and to the growth of certain types of morbidity and
mortality is still a matter of debate among professionals, given the complexity of the interaction of
many different factors and difficulties to identify the factors of diseases. The following table
provides a list of common human diseases that may be associated with environmental pollution.
The list of diseases related to air pollution
Pathology
Substances causing the pathology
sulfur oxides, carbon monoxide, nitrogen oxides,
Diseases of the circulatory system
sulfur compounds, hydrogen sulfide, ethylene,
propylene, butylene, fatty acids, mercury, lead
Diseases of the nervous system and chromium sulfide, silicon dioxide, mercury
sensory organs. Mental disorders
dust, oxides of sulfur and nitrogen, carbon
Respiratory diseases
monoxide, sulfur dioxide, phenol, ammonia,
hydrocarbons, silicon dioxide, chlorine, mercury
Carbon disulfide, hydrogen sulfide, dust,
Digestive diseases
nitrogen oxides, chromium, phenol, silicon
dioxide, fluorine
oxides of sulfur, carbon, nitrogen, hydrocarbon,
Diseases of the blood and bloodhydrazoic acid, ethylene, propylene, hydrogen
forming organs
sulfide
Diseases
of
the
skin
and fluorine-containing substances
subcutaneous tissue
carbon disulfide, carbon dioxide, hydrocarbons,
Diseases of the genito-urinary
hydrogen sulfide, ethylene, sulfur oxide,
organs
butylene, carbon monoxide
The impact of pollution on the body is very diverse and depends on the type, concentration,
duration and frequency of exposure. In turn, the response of the body is determined by the
individual characteristics, age, sex, state of health. In general, more vulnerable children, the sick,
persons working in harmful working conditions, smokers. Yet repeatedly registered and studied the
phenomenon of increased mortality and morbidity in areas with high air pollution indicate that
evidence of such mass and impact on environmental pollution.
According to estimates of the World Health Organization (WHO) there are five categories of
public health responses to environmental pollution:
1) increase in mortality;
2) increase incidence;
3) presence of functional changes in excess of the norm;
4) presence of functional changes that do not exceed the norm;
5) the relatively safe state.
These categories can be seen as relative indicators, collectively characterize the human health
and environmental quality. health indicators, first and foremost, is the amount of health, ie, the
average life expectancy. If we keep in mind this figure is among the most important environmental
risk factors include: 1) air pollution; 2) contamination of drinking water.
Experts estimate air pollution reduces life expectancy by an average of 3-5 years.
Depending on the dose, timing and nature of exposure to chemical contaminants in humans
develop acute or chronic poisoning, and have a remote place pathogenic pathological processes.
Short-term intake of large quantities of toxic substances leads to the development of
symptomatic disease process - acute poisoning. Such poisoning is divided into mild, moderate and
severe. The latter is sometimes fatal.
Chronic poisoning due to systematic or periodic intake of relatively small quantities of toxic
substances. These poisonings rarely have a distinct clinical picture. Their diagnosis is very
complicated, because the same thing in some individual substance causes damage to the liver,
while others - forming organs, the third - the kidneys, in the fourth - the nervous system. Only a
small number of chemical pollutants when exposed to small doses cause a strictly specific disease
process, the vast majority also gives the so-called general toxic effect.
By "remote consequences" or "long-term effects" we mean the impact of chemical pollutants
development of disease processes and disease states in humans who have contact with the
chemical pollutants in the environment long-term periods of their lives, as well as during the life of
several generations of their offspring. Long-term effects of combined broad group of pathological
processes. Pathological phenomena in the nervous system in a more remote period after the
chemical effects cause diseases such as Parkinson's disease, polyneuritis, paresis and paralysis,
psychosis; in the cardiovascular system - heart attacks, coronary insufficiency, etc.
Long-term effects with the effects of a carcinogenesis (formation of malignant tumors)
mutagenesis (hereditary disorders at the genetic level), embrinotropnoe (the inner fruit) poisons.
The importance of long-term effects can be seen in the statistics of mortality from
cardiovascular disease (50%), malignant neoplasms (20%) in industrialized cities.
Respiratory organs are the most sensitive to the effects of atmospheric pollution. The organism
intoxication occurs through the alveoli of the lungs, which area (capable of gas exchange) is more
than 100 m2. In the process of gas exchange in the blood comes toxicants. Suspended solids of
various particle sizes are deposited in various parts of the respiratory tract.
Atmospheric aerosols can also have pathogenic effects on human, and as metal-organic
particles are carcinogenic.
Atmospheric path of toxic substances in the human body is the lead, as during the day, it
consumes about 15 kg of air, 2.5 kg of water and about 1.5 kg of food further chemical elements
absorbed by the body more rapidly by inhalation. Thus, the lead coming from the air is absorbed
by the blood at approximately 60%, whereas the incoming water - 10%, and food - only 5%.
Atmospheric pollution caused by up to 30% of common diseases of the industrial centers
population.
Currently, the car is in the first place in absolute emissions of gases. He is the source of almost
half of the air pollutants. The main cause of damage is the carbon monoxide, but a negative effect
on the human body is also noticed from the carbohydrates, nitrogen oxides contained in the
exhaust gas, and photochemical oxidants.
Nitrogen oxides in contact with a moist surface lung appears in acid form, and those in turn nitrates and nitrites. As the acids themselves, and their derivatives irritating to mucous
membranes, especially deep respiratory tract, which can lead to reflex and breathing disorders
even pulmonary edema. Moreover, nitrates and nitrites are converted to oxyhemoglobin metahemoglobin, which causes .oxygen failure.
Among the sources of pollution that negatively affect human health, the car plays an important
but not the main role. Cars are responsible for 10-25% of diseases, although, as we have said,
produce nearly half of all air pollutants. The sulfur oxides and a variety of fine particles (soot
mixture, ash, dust, sulfuric acid droplets, asbestos fibers, etc.) cause more disease than vehicle
exhaust. They enter the atmosphere from power plants, factories and homes. The sulfur oxides
and dust particles tend to concentrate in areas of most intensive burning of coal, they are
dangerous, especially in winter, when more fuel is burned.
Photochemical smog, on the contrary, is more dense in the summer. Polluted air affects
primarily the lungs, the most dangerous are sulfur oxides and fine particles. Among the respiratory
diseases we distinguish acute (colds, bronchitis, pneumonia). All countries have the prevalent
respiratory diseases for more cases than all other diseases combined. Qatar upper respiratory
tract is still the most common disease.
Environmental pollution affects the occurrence of diseases such as lung cancer, although the
main role in the pathogenesis of this disease belongs to smoking. For residents of large cities in
the likelihood of the disease by about 20-30% higher than for people living in villages or small
towns. The relationship between the content of particulate matter in the air and the frequency of
gastric cancer and prostate cancer. It is assumed that in the air of nitrogen oxides combine with
other impurities to form nitrosamines - substances belonging to the most active carcinogens.
In Moscow alone annually released into the atmosphere about 120 thousands of tons of
nitrogen oxides. Apparently, in the occurrence of lung cancer are involved and radioactive particles
scattered throughout the world in connection with the testing of nuclear weapons and the activities
of nuclear power plants. Among the various radioactive substances most dangerous plutonium,
featuring a very slow decay.
There are data on the effect of air pollution on mortality from coronary heart disease. There are
a lot of such cases during extreme contamination. The reason lies partly in the fact that the
shortness of breath increases the load on the heart. Another explanation -negative impact on the
heart of the carbon monoxide.
There is a connection between air pollution with an increase in the genetic nature of the
disease and the level of congenital malformations in industrial cities. It depended not only on
pollution intensity, but also on the nature of atmospheric emissions. A number of chemicals have
mutagenic effect, which can manifest itself in an increase in the frequency of chromosome
aberrations in somatic and germ cells, which leads to tumors, spontaneous abortion, perinatal
death, developmental abnormalities and infertility.
The adverse pregnancy and birth In polluted areas occure more frequently. Children born after
abnormal pregnancy in polluted air emissions areas often have low body weight and the level of
physical development, as well as functional abnormalities of the cardiovascular and respiratory
systems.
It noted that there is different varying intensity effect of factors on the man. Thus, a high degree
of air pollution causes growth retardation and developmental processes, the growing disharmony
due increase of fat deposition, and low concentrations of harmful substances activate the
processes of acceleration. Comparison of anthropometric data in children showed that height,
weight and chest circumference in an area with polluted air is greater than in areas with less
pollution. This phenomenon indicates a possible stimulation of physical development impact of
adverse external factors of low intensity (height and weight of the largest quantities of the body is
achieved in areas with moderate pollution). However, this acceleration of physical development is
accompanied by a noticeable weakening of the efficiency of the cardiovascular system.
An interconnection of toxic substances in the blood, urine, hair, and other tissues of humans
with the degree of their harmful effects on the body. The concentration of the substance in the
tissues and secretions of the exponent is negative influence on the body. A relationship between
the levels of cadmium and lead in hair of schoolchildren and their mental development. The most
common of toxic heavy metals - lead, since it is part of the gasoline. Transportable by air, nickel,
cadmium, beryllium, and mercury are relatively rare, but in some areas they are a serious threat.
And particularly dangerous is that the accumulation of these metals in the body begins with the
contamination level is much lower than the MPC.
In many large industrial cities the severe pollution of the atmosphere leads to a decrease in its
transparency to sunlight and to a large extent for the FIM. Dust, soot, sulfur dioxide and other air
pollutants by absorbing short-wave part of the solar spectrum reduce the total amount reaching
the surface of the natural UV radiation and create conditions of relative UV deficit medium
latitudes (52,5-57,5 ° northern latitude .), where the conditions of uncontaminated atmosphere
holds UV - comfort, and exacerbate UV - deficit north of 57.5 ° N The lack of UV resistance
reduces organism to unfavorable factors, including chemical pollution of the environment.
UV radiation – is a prerequisite for normal human life. It kills microorganisms on the skin,
prevents rickets, normalizes mineral metabolism, increases resistance to infectious and other
diseases. Children who have received a sufficient amount of ultraviolet radiation that is ten times
less susceptible to colds than children who did not receive a sufficient amount of UV irradiation.
At its lack impaired calcium and phosphorus metabolism, increases susceptibility to infections
and colds, appear functional disorders of the central nervous system, certain chronic diseases are
aggravated, the physiological activity is reduced overall, and hence the capacity of man.
Natural and associated air pollution artificial UV deficit requires preventive measures to
compensate for the lack of natural UV radiation - differentiated (depending on the degree of UV
deficit) prevention of UV irradiation of the population, especially children and the frail. At the same
time, according to doctors, the person should get a year of not less than 45 "servings Sun," ie,
erythemal doses of ultraviolet radiation. Naturally, the area is located to the north, the more you
have to spend time trying to dial this norm.
The least comfortable for living in a large industrial city are urban districts with high
transportation and industrial pressing, irrational layout, without sufficient buffer zones between
industrial and residential buildings, reduced self-purification capacity of the atmosphere. "Zones of
ecological risk" are usually the areas adjacent to major transport communications – highways
Environmental contamination by harmful substances and their effect on human health - this is
one of the most important issues to date, requiring immediate solutions.
In order to prevent the adverse effects of pollution on health, you can use several approaches.
Efforts should be made to improve the environment, emission control, as well as to monitor and
control environmental pollution. Thus it will be possible to achieve improvement of the environment
in general.
Anthropogenic air pollution and public health
Anthropogenic pollution has a significant impact on the formation of population health,
particularly in relation to changing socio-economic conditions. Therefore the problem of adverse
effects of the environment on health is becoming increasingly important with each passing year.
Determination of quantitative relationships in the "Environment - health" as a priority
environmental health was made by G.I. Sidorenko in the late 60's - early 70's and was later
developed in criteria and methods to quantify the impact of environmental factors.
The contribution of anthropogenic factors in the formation of health deviation is between 10
and 57%
In the Russian Federation there are a difficult and unfortunate, and even severe
environmental conditions in some areas. 109 million of people live in poor sanitary conditions or
73% of the population
One of the leading factors of anthropogenic impact on health is inhalatory. The influence on
the human body may show mainly three types of pathological effects.
1. Acute intoxication occurs when one-stage admission toxic inhalation dose. Toxic
manifestations are characterized by the acute onset of severe and specific symptoms of
poisoning
2. Chronic intoxication due to the lengthy, often discontinuous, intake of chemicals in the
sub-toxic doses, begins with the appearance of special symptoms.
3. Long-term effects of exposure to toxicants.
а) Gonadotropic effect is the impact on spermatogenesis in men and women ovogenesis,
causing reproductive dysfunction of a biological object.
б) Embryotropic effect is impaired in utero development of the fetus:
- Teratogenic effects - the emergence of disorders of organs and systems, manifested in postnatal
development;
- Embryotoxic effect - fetal death, or reducing its size and weight in the normal differentiation of
tissues.в) Мутагенный эффект – изменение наследственных свойств организма, за счет нарушений
ДНК.
g) Carcinogenic effect - the development of benign and malignant tumors.
Results of medical and environmental and health studies strongly suggest that air pollution
causes certain symptoms of toxic reactions in the population, from the early stages of ontogeny.
The exhaust gases - spent working fluid in the engine. They are a product of oxidation and
incomplete combustion of hydrocarbon fuels. Exhaust gas emissions - the main reason for
exceeding the allowable concentrations of toxic substances and carcinogens in the atmosphere of
large cities, the formation of smog, are a common cause of poisoning in enclosed spaces.
The greatest danger is posed by nitrogen oxides, about 10 times more dangerous than
carbon monoxide, aldehydes share of toxicity is relatively small and is 4-5% of the total toxicity of
exhaust gases. Toxicity of different hydrocarbons is very different, however, is particularly
dangerous that the unsaturated hydrocarbons in the presence of nitrogen dioxide photochemically
oxidized, forming toxic oxygen compounds - components of smog.
Discovered in gases polycyclic aromatic hydrocarbons - potent carcinogens.
Also when using sulfur gasoline the exhaust gases may include sulfur oxides, when used
leaded gasoline - lead, bromine, chlorine, and their compounds. It is believed that aerosols halide
of lead compounds may be subjected to catalytic and photochemical reactions, participating in the
formation of smog.
Prolonged contact with the environment, poisoned by car exhaust fumes causes a general
weakening of the body - immune deficiency. In addition, the gases themselves can cause various
diseases. For example, respiratory failure, sinusitis, laryngotracheitis, bronchitis, pneumonia, lung
cancer. Moreover, the exhaust gases cause cerebral atherosclerosis. Indirectly through the
pulmonary abnormalities may occur and various disorders of the cardiovascular system.
Vehicle exhaust gases disrupt brain function. This is the opinion of the Dutch researchers
studied the effects of air pollution on the human body. It was found, that even brief inhalation
exhaust gases may cause changes in the brain.
To study the influence of the exhaust gas on the brain scientists helped 10 volunteers.
Within an hour, most of them are in the room with fresh air, the other part - in the room with diesel
exhaust gases. In the course of the experiment and after the parties doing brain EEG.
The people who were in the room with the exhausts, were found changes in brain activity.
Even short-term inhalation of exhaust fumes can cause headache, nausea and dizziness.
Prolonged exposure to diesel exhaust, according to doctors, could disrupt the processing of
information in the brain.
Experiment of Dutch scientists showed that exhaust fumes affect brain function negatively.
Changes its activity can lead to serious mental illness.
Among the sources of pollution that negatively affect human health, the car plays an
important but not the main role. Cars are responsible for 10-25% of diseases. The sulfur oxides
and a variety of fine particles (soot mixture, ash, dust, sulfuric acid droplets, asbestos fibers, etc.)
cause more disease than vehicle exhaust. They enter the atmosphere from power plants, factories
and homes. It is proved that a high concentration of sulfur oxides and fine particles during
exacerbates chronic respiratory and cardiovascular diseases. Polluted air affects primarily the
lungs, the most dangerous of sulfur oxides and fine particles.
Environmental pollution affects the occurrence of diseases such as lung cancer, although
the main role in the pathogenesis of this disease belongs to smoking. For residents of large cities
in the likelihood of the disease by about 20-30% higher than for people living in villages or small
towns. The relationship between the content of particulate matter in the air and the frequency of
gastric cancer and prostate cancer. It was obtained the data of air pollution effect on mortality from
coronary heart disease. Air pollution has aroused great concern to the people than any other form
of environmental degradation.