Basic research. Environmental diseases Environmental causes of disease
table 2
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The elements |
Effects of exposure to elements |
Sources of |
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Elevated concentrations |
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Nervous disorders (minamata disease). Dysfunction of the gastrointestinal tract, changes in chromosomes. |
Contamination of soil, surface and ground waters. |
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Cancer of the skin, intonation, peripheral neuritis. |
Soil pollution. Pickled grain. |
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The destruction of bone tissue, a delay in protein synthesis in the blood, a violation of the nervous system and kidneys. |
Contaminated soils, surface and underground waters. |
|
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Organic tissue changes, bone breakdown, hepatitis |
Contamination of soils, surface and ground waters. |
|
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Liver cirrhosis, impaired renal function, proteinuria. |
Soil pollution. |
Minamata disease is a disease of humans and animals caused by mercury compounds. It has been established that some aquatic microorganisms are capable of converting mercury into highly toxic methylmercury, which increases its concentration along the food chains and accumulates in significant quantities in the organisms of predatory fish. Mercury enters the human body with fish products, in which the mercury content may exceed the norm. Thus, such fish may contain 50 mg / kg of mercury; moreover, when such fish is eaten, it causes mercury poisoning when raw fish contains 10 mg / kg. The disease manifests itself in the form of nerve disorders, headache, paralysis, weakness, loss of vision and can even lead to death.
Itai-tai disease is human poisoning caused by eating rice containing cadmium compounds. This disease has been known since 1955, when wastewater from the Mitsui concern containing cadmium entered the irrigation system of rice fields. Cadmium poisoning can cause apathy, kidney damage, softening of bones, and even death in people. In the human body, cadmium mainly accumulates in the kidneys and liver, and its damaging effect occurs when the concentration of this chemical element in the kidneys reaches 200 μg / g. Signs of this disease are recorded in many regions of the world; a significant amount of cadmium compounds enter the environment. Sources are: combustion of fossil fuels at thermal power plants, gas emissions from industrial enterprises, production of mineral fertilizers, dyes, catalysts, etc. Assimilation - absorption of water and food cadmium is at the level of 5%, and air up to 80%. For this reason, the content of cadmium in the body of residents of large cities with their polluted atmosphere can be ten times higher than that of residents of rural areas. Typical "cadmium" diseases of the townspeople include: hypertension, coronary heart disease, renal failure. For smokers (tobacco strongly accumulates cadmium salts from the soil) or those employed in production using cadmium, pulmonary emphysema is added to lung cancer, and for nonsmokers - bronchitis, pharyngitis and other respiratory diseases.
Yusho disease - human poisoning with polychlorinated biphenyls (PCBs) - has been known since 1968. In Japan, a rice oil refining plant leaked befinyls from refrigeration units into the product. The poisoned oil was then marketed as food and animal feed. First, about 100 thousand chickens died, and soon people began to show the first symptoms of poisoning. This was reflected in a change in skin color, in particular, darkening of the skin in children born to mothers who have suffered from PCB poisoning. Later, severe damage to internal organs (liver, kidneys, spleen) and the development of malignant tumors were discovered. The use of certain types of PCBs in agriculture and public health in some countries for the control of vectors of infectious diseases has led to their accumulation in many types of agricultural products, such as rice, cotton, vegetables. A certain amount of PCBs is released into the environment from waste incineration plants, which poses a hazard to the health of urban residents. Therefore, in many countries, the use of PCBs is limited or used only in closed systems.
Disease "yellow children" - the disease appeared as a result of the destruction of intercontinental ballistic missiles, which led to the release of toxic components of rocket fuel into the environment: UDMH (unsymmetrical dimethylhydrazine or gentil) - the main component of rocket fuel, as well as nitrogen tetroxide (both belong to the first class danger). These compounds are very toxic, enter the human body through the skin, mucous membranes, upper respiratory tract, gastrointestinal tract. As a result, children with pronounced signs of jaundice began to be born. The incidence of newborns has increased 2-3 times. The number of newborns with lesions of the central nervous system has increased. Infant mortality has increased. Due to the release of these substances, skin "burns" appeared - pustular diseases that can appear after swimming in local rivers, going to the forest, direct contact of naked body parts with the soil, etc.
"Chernobyl disease" On April 26, 1986 there was an explosion at the 4th power unit of the Chernobyl nuclear power plant. The emission of radionuclides was 77 kg. (Hiroshima - 740 gr.). 9 million people were affected. The contaminated area was 160 thousand km. The composition of the radioactive fallout included about 30 radionuclides such as: krypton - 85, iodine - 131, cesium - 317, plutonium - 239. The most dangerous of them turned out to be iodine - 131, with a short half-life. This element enters the human body through the respiratory tract, concentrating in the thyroid gland. The local population showed symptoms of "Chernobyl disease": headache, dry mouth, swollen lymph nodes, cancer of the larynx and thyroid gland. Also, in the areas affected by the Chernobyl accident, the incidence of the cardiovascular system has increased, outbreaks of various infections have become more frequent, and the birth rate has significantly decreased. The frequency of mutations among children increased 2.5 times, anomalies were found in every fifth newborn, about a third of children were born with mental disorders. Traces of the Chernobyl "event" in the genetic apparatus of mankind, according to the testimony of doctors, will disappear only after 40 generations.
Introduction
Humanity has long been interested in the influence of the environment on health and the occurrence of diseases. As early as 500 BC, Hippocrates (Clifton, 1752) in his work "On Air, Water and Situation" wrote about the importance of the environment for human health, where he described the effects of weather and different seasons, water characteristics and the location of cities. He urged to consider the conditions in which the population lives, as well as their habits: "whether they like to eat and drink too much, how much they like to work, and whether they like physical activity." Over the centuries, this concern about the state of the environment has shifted from general theories about the occurrence of environmental diseases to today's highly focused and mechanistic formula aimed at specific agents or groups of agents and specific diseases.
Occupational diseases are a group of diseases that arise exclusively or mainly as a result of exposure to the body of unfavorable working conditions and occupational hazards. The profession of a firefighter in itself implies that from time to time they expose themselves to increased physical and psychological stress, as well as to serious chemical and physical hazards that workers in other modern workplaces do not usually expose themselves to. Injury, burns and smoke inhalation are the greatest health hazards for firefighters. The occupational risks of firefighters deserve more attention due to the well-known constant contact with toxic substances.
CHEMICAL POLLUTION OF THE ENVIRONMENT AND HUMAN HEALTH.
Currently, human economic activity is increasingly
becomes the main source of pollution of the biosphere. Into the natural environment
in increasing quantities gaseous, liquid and solid
production waste. Various chemicals found in
waste, getting into soil, air or water, passes on ecological
links from one chain to another, eventually enter the body
person.
The body's responses to pollution depend on individual
features: age, gender, health status. As a rule, more
children, elderly and elderly people, sick people are vulnerable.
Highly biologically active chemical compounds can
cause a long-term effect on human health: chronic
inflammatory diseases of various organs, changes in the nervous system,
effect on the intrauterine development of the fetus, leading to various
deviations in newborns.
Doctors have established a direct link between the increase in the number of people suffering from
allergies, bronchial asthma, cancer, and environmental degradation
the situation in the region. It has been reliably established that such waste
production like chromium, nickel, beryllium, asbestos, many pesticides,
are carcinogens, that is, they cause cancer.
Smoking causes great harm to human health. Smoker not only
himself inhales harmful substances, but also pollutes the atmosphere, exposes
danger of other people. It has been established that people who are in the same
in a room with a smoker, they inhale even more harmful substances than he himself.
BIOLOGICAL POLLUTION AND HUMAN DISEASES.
In addition to chemical pollutants, there are also
biological, causing various diseases in humans. it
pathogens, viruses, helminths, protozoa. They can
be in the atmosphere, water, soil, in the body of other living organisms, in
including in the person himself.
The most dangerous are pathogens of infectious diseases. They have
various resistance to the environment. Often the source of infection is the soil, which is constantly inhabited by pathogens of tetanus, botulism, gas gangrene, and some fungal diseases. They can get into the human body if the skin is damaged, with unwashed food, if the rules of hygiene are violated.
Pathogens can enter groundwater and become
cause of human infectious diseases. Therefore, water from artesian
wells, wells, springs must be boiled before drinking.
Open water sources are especially polluted: rivers, lakes,
ponds. There are numerous cases when contaminated water sources
caused epidemics of cholera, typhoid fever, dysentery.
People and pets can become infected with natural focal diseases,
getting into the territory of a natural hearth. Such diseases include the plague,
tularemia, typhus, tick-borne encephalitis, malaria, sleeping sickness.
INFLUENCE OF SOUNDS ON A PERSON.
Man has always lived in a world of sounds and noise. For all living organisms, including humans, sound is one of the effects of the environment.
High-power sounds and noises affect the hearing aid,
nerve centers can cause pain and shock. This is how it works
noise pollution.
The quiet rustle of foliage, the murmur of a stream, bird voices, a light splash of water and
the sound of the surf is always pleasant to man. They calm him down, take him off
stress. But the natural sounds of the voices of nature are becoming more and more
rare, disappear completely or are drowned out by industrial transport and
other noises.
Prolonged noise adversely affects the organ of hearing, lowering
sensitivity to sound. It leads to a breakdown in the activity of the heart, liver, exhaustion and overstrain of nerve cells.
Noise level is measured in units expressing the degree of sound
pressure, - decibels. A noise level of 20-30 decibels (dB) is practically harmless to humans, it is a natural background noise. A sound of 130 decibels already causes a painful sensation in a person, and 150 becomes unbearable for him.
The level of industrial noise is also very high. In many jobs and noisy
In industries, it reaches 90-110 decibels and more. Not much quieter and
us at home, where new sources of noise appear - the so-called
Appliances.
Very noisy modern music also dulls the ear and causes nervous diseases. Noise has accumulative effects, that is, acoustic irritation, accumulating in the body, depress the nervous system more and more.
Therefore, before hearing loss from exposure to noise occurs
functional disorder of the central nervous system. Especially
noise has a harmful effect on neuropsychic activity
organism. Noises cause functional disorders of the cardiovascular system; have a harmful effect on the visual and vestibular analyzers, reduce reflex activity, which often causes accidents and injuries.
Studies have shown that inaudible sounds can also be harmful
impact on human health. So, infrasounds have a special effect on the human mental sphere: all types of intellectual activity are affected, mood deteriorates, sometimes there is a feeling of confusion, anxiety, fright, fear, and at high intensity - a feeling of weakness, as after a strong nervous shock.
Ultrasounds, which occupy a prominent place in the range of industrial noise,
are also dangerous. The mechanisms of their action on living organisms are extremely
diverse.
WEATHER AND HUMAN FEEL
In any phenomenon of the nature around us, there is a strict repetition
processes: day and night, ebb and flow, winter and summer.
In the course of historical development, man has adapted to a certain
the rhythm of life due to rhythmic changes in the natural environment and
energy dynamics of metabolic processes.
Currently, many rhythmic processes in the body are known,
called biorhythms. These include the rhythms of the heart, breathing,
bioelectric activity of the brain. Our whole life is
constant change of rest and vigorous activity, sleep and wakefulness,
fatigue from strenuous work and rest.
The central place among all rhythmic processes is occupied by diurnal
rhythms that are of greatest importance to the body. It turned out that the study of changes in circadian rhythms makes it possible to identify the occurrence of some diseases at the earliest stages.
The climate also has a serious impact on human well-being,
influencing it through weather factors. Weather conditions include
a complex of physical conditions: atmospheric pressure, humidity,
air movement, oxygen concentration, degree of disturbance
the earth's magnetic field, the level of atmospheric pollution.
With a sharp change in weather, physical and mental performance decreases, illnesses become aggravated, and the number of errors, accidents and even deaths increases.
Examples of some environmental diseases
Minamata disease - a disease of humans and animals caused by mercury compounds. It has been established that some aquatic microorganisms are capable of converting mercury into highly toxic methylmercury, which increases its concentration along the food chains and accumulates in significant quantities in the organisms of predatory fish.
Mercury enters the human body with fish products, in which the mercury content may exceed the norm.
The disease manifests itself in the form of nerve disorders, headache, paralysis, weakness, loss of vision and can even lead to death.
Itai-itai disease - human poisoning caused by eating rice containing cadmium compounds. This etching can cause apathy in people, kidney damage, softening of the bones, and even death.
In the human body, cadmium mainly accumulates in the kidneys and liver, and its damaging effect occurs when the concentration of this chemical element in the kidneys reaches 200 μg / g.
Sources are: combustion of fossil fuels at thermal power plants, gas emissions from industrial enterprises, production of mineral fertilizers, dyes, catalysts, etc. The content of cadmium in the body of residents of large cities with their polluted atmosphere can be ten times higher than that of residents of rural areas. Typical "cadmium" diseases of the townspeople include: hypertension, coronary heart disease, renal failure. For smokers (tobacco strongly accumulates cadmium salts from the soil) or those employed in production using cadmium, lung cancer is added
emphysema of the lungs, and for non-smokers - bronchitis, pharyngitis and other respiratory diseases.
"Chernobyl disease" - caused by the impact of radionuclides on the human body, emitted as a result of the explosion of the fourth reactor of the Chernobyl nuclear power plant. The local population showed symptoms of "Chernobyl disease": headache, dry mouth, swollen lymph nodes, cancer of the larynx and thyroid gland. Also, in the areas affected by the Chernobyl accident, the incidence of the cardiovascular system has increased, the outbreaks of various infections have become more frequent, and the birth rate has significantly decreased.
The frequency of mutations among children increased 2.5 times, anomalies were found in every fifth newborn, about a third of children were born with mental disorders.
Occupational diseases are a group of diseases that arise exclusively or mainly as a result of exposure to the body of unfavorable working conditions and occupational hazards.
In my essay, I want to draw attention to the professional hazards that firefighters expose themselves to.
Putting out a fire is quite an extraordinary activity, and although there is an idea of it as a dirty and dangerous business, nevertheless, it is absolutely necessary and prestigious. Firefighters are respected by the public for the extraordinarily important work they do. And firefighters are fully aware of the dangers they may face. Their work in itself suggests that from time to time they expose themselves to increased physical and psychological stress, as well as serious chemical and physical hazards that workers in other modern workplaces do not usually expose themselves to.
The occupational hazards to which firefighters expose themselves can be divided into the following categories: physical (mainly unsafe environment, overheating and ergonomic stress), chemical and psychological.
Physical hazards
.
There are many physical hazards in the process of fighting a fire that result in serious physical injury. Walls, ceilings and floors suddenly collapse, dragging firefighters with them. Sudden intensification of fire and bursts of flame in an enclosed space, which can occur as a result of the sudden ignition of combustible gaseous products released by burning or incandescent materials when interacting with overheated air. The sudden flames can engulf the firefighter or cut off his escape route. The number and severity of injuries can be minimized through increased training, work experience, competence and good physical fitness. However, the nature of the work is such that firefighters may find themselves in a dangerous situation due to miscalculation, circumstances or during a rescue operation.
Several fire departments have compiled computer databases of buildings under their control, materials and potential hazards they may face while fighting a fire in their area. Quick access to the database of such data helps the team to react in a timely manner to emerging dangers and to predict the occurrence of dangerous situations.
Thermal hazards
Overheating during extinguishing a fire can occur as a result of contact with hot air, heat radiation, hot surfaces, as well as due to internal heat generated during work by the human body, which cannot be cooled until the fire is extinguished. The insulating properties of protective clothing and physical fatigue from excess body heat can cause overheating when fighting a fire. Overheating can cause injury such as burns or general overheating, which can lead to dehydration, heatstroke, and heart attack.
The hot air itself is usually not a serious threat to the firefighter. Dry air cannot retain heat for long. Steam or hot, humid air can cause severe burns because steam contains much more heat energy than dry air. Fortunately, steam burns are not common.
Heat radiation is often quite intense during a fire. Burning is possible if there is only heat radiation. Some firefighters experience changes in their skin due to constant exposure to heat.
Chemical hazards
More than 50 percent of fire-related fatalities are the result of contact with smoke, not fire. One of the significant contributing factors to death and illness from fire is hypoxia due to lack of oxygen in the atmosphere, which leads to loss of physical activity, disorientation and loss of mobility. The constituents of the smoke, individually and collectively, are also toxic. Figure 95.3 shows a self-contained breathing apparatus (SCBA) firefighter rescuing an unprotected firefighter who is caught in a very smoky fire from a burning tire warehouse. (The rescued firefighter ran out of air, took off his breathing apparatus to take a deep breath, and was lucky to be rescued before it was too late.)
Rice. 95.3 One firefighter rescues another, caught in toxic smoke, in a fire in a closed warehouse
Any smoke, including smoke from a burning tree, is dangerous and potentially fatal if inhaled in concentrated doses. Smoke is made up of a combination of different components. The toxicity of smoke primarily depends on the fuel, the heat capacity of the flame and how much oxygen is available for its combustion, or whether it is available at all. At the site of a fire, firefighters are often exposed to carbon monoxide, nitrogen dioxide, sulfur dioxide, hydrogen chloride, hydrogen cyanide, aldehydes, and organics such as benzene. Combinations of different gases present different levels of hazard. Only carbon monoxide and hydrogen cyanide are released in lethal concentrations in building fires. Carbon monoxide is the most common, specific and very serious fire hazard. Due to the close proximity of carbon monoxide to hemoglobin, carboxyhemoglobin rapidly accumulates in the blood as it stays in an atmosphere containing carbon monoxide. High levels of carboxyhaemoglobin accumulation may be primarily caused by severe fatigue increasing ventilation in the lungs, and thus the entry of air into the lungs in the absence of protective equipment when fighting a fire. There is no clear relationship between smoke intensity and the amount of carbon monoxide in the air. During the stripping procedure, when combustible materials are smoldering and have not yet completely burned out, firefighters should avoid smoking as this increases the level of carbon monoxide in the blood. Hydrogen cyanide is produced by the low-temperature combustion of nitrogen-rich materials, including natural fibers such as wood and silk, as well as less common synthetic materials such as polyurethane and polyacrylonitrile.
When hydrocarbon fuels are burned at low temperatures, light hydrocarbons, aldehydes (such as formaldehyde) and organic acids can be formed. Significant amounts of nitric oxide are formed at high temperatures - as a result of the oxidation of nitrogen contained in the atmosphere, and at low combustion temperatures of fuels, which contain a lot of nitrogen. If the fuel contains chlorine, hydrogen chloride is formed. Polymeric plastics are particularly hazardous. These plastic materials began to be used in the construction and decoration of buildings in the fifties and later. They burn, turning into highly hazardous substances. Acrolein, formaldehyde, and volatile fatty acids are very common products of the smoldering combustion of some polymers, including polyethylene and natural cellulose. The danger of cyanine formation increases with an increase in the combustion temperature at which polyurethane and polyacrylonitriles are burned: at temperatures above 800, but below 1000 degrees Celsius, acrylonitrile, acetonitrilepyridine, benzonitrile are released in large quantities. For the decoration of buildings, it is preferable to use polyvinyl chloride due to its self-extinguishing, due to its high chlorine content. Unfortunately, the material releases hydrochloric acid in large quantities, and sometimes, if the fire continues long enough, dioxides.
Synthetic materials are especially hazardous in the smoldering process and not in high temperature environments. Cement retains heat quite effectively and can act as a "sponge", accumulating gases that then escape through the porous material, releasing hydrogen chloride and other toxic fumes long after the fire has been extinguished.
Psychological hazards
Firefighters work in situations that other people diligently avoid, putting themselves at much greater risk than any other civilian profession. No matter how intense a fire is, much can go wrong, and the course of a major fire is often unpredictable. In addition to personal safety, the firefighter must take care of the safety of other people who are in danger of fire. Rescuing victims is a particularly strenuous job.
The life of a professional firefighter is an endless series of tense anticipation and stressful crises. Firefighters, however, enjoy many of the positive aspects of their work. Rarely is there a profession so respected in society. Safety at work is ensured by the fire department that hired the firefighter, and the salary here is usually higher than in other professions. Firefighters also have a strong sense of camaraderie and affection for their colleagues. These positive aspects of work outweigh the stressful moments and save the firefighter from the emotional consequences of repetitive stress.
When the alarm sounds, the firefighter immediately feels anxious anticipation of the unpredictability of the situation he will have to face. The psychological stress experienced at the moment is as great or even greater than in the process of extinguishing a fire. Psychological and biochemical stress gauges indicate that firefighters on duty experience psychological stress, which reflects subjectively perceived factors of psychological stress and activity level while on duty.
Lungs' cancer.
In epidemiological studies of firefighters, it is most difficult to distinguish lung cancer from other cancers. The main question is whether the use of synthetic materials, since the fifties, in building and finishing materials, has increased the risk of cancer among firefighters, due to contact of firefighters with combustion products. Despite obvious exposure to smoke-inhaled carcinogens, it has been difficult to document and consistently document an increase in lung cancer mortality in light of occupational consequences.
There is evidence that firefighters' work increases the risk of lung cancer. This is especially true among firefighters who expose themselves to the greatest danger and have the greatest work experience. An additional risk may be superimposed on an even greater risk from smoking.
Reflections on the relationship between firefighters' work and lung cancer suggest that the relationship is weak and does not suggest that the risk should be attributed to the profession. Certain cases with unusual characteristics, such as cancer among relatively young, nonsmoking firefighters, may support this conclusion.
Other types of cancer.
Other cancers have recently been shown to be more consistently associated with firefighters than lung cancer.
Different literatures provide different data on brain and central nervous system cancers, and this is not surprising, since in all the reports the number of described cases is relatively small. It is unlikely that this connection would receive clarification in the near future. It is therefore reasonable to recognize the risk of this disease as an occupational disease for firefighters based on the available evidence.
It seems that the risk of cancer of the lymphatic and hematopoietic systems is quite high. However, the small number of cases of these rare cancers makes it difficult to determine the significance of their association with the profession. Since these types of cancer are rare, for statistical purposes, epidemiologists consider them in the same group, which makes them even more difficult to interpret, since from a medical point of view it does not make sense.
Heart diseases.
There is no convincing answer to the question of whether people are at increased risk of dying from heart disease. Although the only large study showed an 11% increase, and another study reported a 52% increase in coronary heart disease mortality, most researchers did not conclude that the risk for the entire population was increasing. Even if the higher estimates are correct, the relative risk estimates are still not sufficient to make an assumption about the risk on a case-by-case basis.
There is evidence, mainly from clinical practice, that exposure to carbon monoxide can cause unexpected decompensation of the heart muscle and the risk of heart attack with sudden overexertion. This does not translate into an increased risk of having a heart attack later, but if a firefighter had a heart attack during the fire or the day after, it could be attributed to his job. Therefore, each case should be considered on a case-by-case basis, but such evidence does not imply an overall increased risk for all firefighters.
Diseases of the lungs
Sufficiently intense contact with the secretions of burning plastic can certainly cause severe lung damage and even permanent disability. Fighting a fire can lead to short-term asthma-like changes that subside over time. This does not appear to result in an increased risk of dying from chronic lung disease over the course of life, unless the poisoning was severe enough (the likelihood of death from the effects of inhalation of smoke) or contact with smoke with unusual properties (especially when polyvinyl chloride (PVC) burns) ...
Chronic lung disease among firefighters has been extensively studied. There is no confirmation of their connection with the profession, and therefore it is impossible to express such assumptions. The exception is those rare cases when a chronic illness is a consequence of dangerous contact, which is confirmed by a medical certificate of complications received.
The general assumption of risk is not warranted in the case of poor professional ties, or when the disease is common in the general population. A more productive approach may be to study individual cases by examining various risk factors and the overall risk picture. The general risk assumption is more applicable to unusual disorders with a high level of relative risk, especially if they are unique or specific to certain professions. Table 95.1 provides a list of specific recommendations and criteria that refute or question predisposition in each case.
Injuries.
Injuries sustained in the process of extinguishing a fire are predictable - these are burns, falls, falling under falling objects. The mortality rate from these causes among firefighters is significantly higher than among workers in other professions. Work in connection with extinguishing a fire involves a high risk of burns, especially when entering the fire and extinguishing it, while inside the flame, for example, holding a fire hose. Burns are also easy to get when fighting a fire in a basement, from an injury sustained shortly before this incident, and from training outside the fire department in which the firefighter is currently working. Falls are most common when using self-contained breathing apparatus and while fighting fires in transport companies.
conclusion.
Fighting a fire is a very serious business that often takes place in extreme conditions. The need to extinguish a fire is always unexpected, in no way predictable, and is characterized by long waiting periods alternating with short periods of intense activity.
Firefighters experience constant stress at a fairly intense level as soon as a fire breaks out. Any additional load in the form of additional equipment or rescue of the victim, however necessary for protection, reduces their productivity, since firefighters are already "using themselves" to the maximum. The use of personal protective equipment imposed new psychological stress on firefighters, but removed others, lowering the level of danger.
During firefighting, body temperature and heart rate go through a certain cycle for several minutes: they increase slightly in response to preparatory work to enter the building, then increase even more due to the ambient heat and increase sharply as a result of workloads in a hot atmosphere. After 20 - 25 minutes, - the usual time allowed for a firefighter to be inside a building using a self-contained breathing apparatus, the psychological load remains within the limits tolerated by an ordinary person. However, when fighting prolonged fires that require re-entry to a building, there is not enough time between changing air containers in a self-contained breathing apparatus to cool the body, which leads to the accumulation of heat, increases body temperature and increases the risk of heat stroke.
A special group of diseases, which were called environmental diseases (not to be confused with endemic ones), have recently been discovered. They are caused by substances alien to organisms - xenobiotics (from the Greek Xenos - alien and bios - life), among which they have a particularly negative effect heavy metal ions(Cadmium, lead, Mercury, etc.) And some binary compounds of non-metals (sulfur (IU) oxide SO2 and nitrogen (IU) oxide NO2).
Metallic mercury and its vapors, which are extremely toxic chemicals, are among the most common “metallic” environmental pollutants. Emissions into the water are especially dangerous, because as a result of the activity of microorganisms inhabiting the bottom, a highly toxic compound, soluble in water, is formed, which causes Minamata disease. (Note! If a mercury thermometer breaks at your home, you should carefully collect all the balls of mercury on a piece of paper, and fill the crevices and unevenness of the floor with sulfur powder. Sulfur easily reacts with mercury, forming a harmless compound HgS.)
Cadmium, its compounds and vapors also belong to acutely toxic substances that are easily absorbed into the bloodstream, affect the central nervous system, liver and kidneys, and disrupt metabolism. Chronic poisoning in small doses (itai-itai disease) leads to anemia and bone destruction. Symptoms of acute poisoning with cadmium salts are accompanied by sudden vomiting and convulsions.
Lead and its compounds are also very toxic. Once in the human body, they accumulate (from accumulation lat - accumulation) in the bones, causing their destruction, and the atoms of this element can accumulate in the renal tubules, causing impairment of the excretory function. Lead compounds are widely used in the production of dyes, paints, pesticides, glass products, and also as an additive to gasoline to increase the octane number, and therefore poisoning with this element occurs more often. Since automobile emissions contain lead compounds, they have now simply covered the entire earth's surface, even reaching Antarctica, where there have never been cars.
Perhaps the most famous outbreak of environmental disease in our country was in the late 80s pp. XX century a case in the city of Chernivtsi, when outwardly healthy children of 2 -3 years of age suddenly began to lose hair and overnight they simply went bald. The cause of this disease, which is called intoxication apletion, was quickly established - poisoning with salts Thalia - a very dangerous xenobiotic. However, it is still unclear where this chemical element came from in such an amount. It should be said that all over the world, and in Ukraine in particular, outbreaks of diseases unknown to medicine caused by the action of various kinds of unnatural substances on the body quite often occur.
What is acid rain... Various oxides of sulfur and nitrogen are powerful environmental pollutants, which are emitted into the atmosphere mainly during the combustion of coal. Substances are dangerous not only because they can cause allergies and asthma, but also because of acid rain. Reacting with atmospheric water (often under the influence of solar radiation), sulfur oxides are converted into solutions of acids - sulfite (SO2 + Н20 = H2SO3), sulfuric (SO3 + Н20 = H2SO4), and nitrogen oxides - nitrogenous and nitric (2N02 - h Н20 = HN03 - h HN02) acids. Then, along with snow or rain, they fall to the ground. Acid rain destroys forests and crops, destroys life in water bodies, increasing their acidity to such a level that plants and animals die in them.
Thus, in the production process and for energy production, a huge amount of waste substances (soot, phosphorus, carbon monoxide, nitrogen oxides, etc.) are emitted into the air and water.
Sulfur, various compounds of metallic elements, etc.), the mass of which in just a year on Earth is millions of tons. Living beings have never encountered most of these compounds, and therefore they cannot utilize them - use them for their needs. Whereas their accumulation inevitably leads to the gradual destruction of the natural environment and is detrimental to all living things. Since modern civilization cannot do without the production of more and more cars, airplanes, tankers, the construction of factories, residential neighborhoods and just cottages, and the transition to environmentally friendly production of matter and energy is still nothing more than a project for the future, there is a need to quota production waste , limiting their free ejection. For this, each country is given a quota, according to which it will be able to pollute the environment for a certain number of tons of emissions per year. But this idea, which, of course, is only a half-measure, does not find real support in the governments of the most developed countries, since in this case a sharp drop in production is expected.
Federal Agency for Education
State educational institution of higher professional education
AMUR STATE UNIVERSITY
(GOUVPO "AmSU")
Faculty of Economics
Department of World Economy, Tourism and Customs
Specialty 036401.65 - Customs
ESSAY
On the topic: Environmental human diseases
In the discipline "Ecology"
Executor
student of group 075а _____________________ T.M. Boy
Checked ____________________ T.V. Ivanykina
Blagoveshchensk
2011
CONTENT
1 HUMAN HEALTH
Human health is the main feature, the main property of the human personality and community, their natural state, reflecting both individual health, and the ability of society in specific conditions to most effectively carry out its biological and social functions. The quality of public health is one of the most important global problems of our time, which is constantly discussed by scientists and politicians around the world.
The concept of “individual health is not strictly determined, which is associated with a variety of factors affecting human health, and a large range of individual fluctuations in the basic indicators of the body's vital activity.
For practical and theoretical medicine and human ecology, it is more important to define the concept of "practical health", or "norm", a deviation from the boundaries of which can be considered a disease (pathology).
To solve scientific and practical problems related to human health, it is necessary to assess or measure its quality. Measuring the quality of health includes various indicators: average life expectancy, standardized mortality, infant mortality, maternal mortality, causes of death, lost years of potential life, morbidity, hospitalization, temporary disability, and disability.
The following factors influence the formation of population health:
- natural conditions (climate, surface and underground waters, geological structure of the territory, soil cover, flora and fauna, stability of natural conditions);
lifestyle and socio-economic conditions, including the quality of health care;
pollution and environmental degradation;
working conditions.
2 ECOLOGICAL DAMAGE AND DISEASE
2.1 Environmental damage
Environmental damage means a significant regional or local violation of environmental conditions, which leads to the destruction of local ecological systems, local economic infrastructure, seriously threatens the health and life of people and causes significant economic damage. Environmental injuries are:
1) abrupt, sudden, catastrophic, associated with emergency situations (ES); 2) extended in time, when the lesion is a prolonged, gradually fading consequence of emergency situations, or, conversely, arises and is detected as a result of gradually increasing negative changes. The scale of such defeats can be no less catastrophic. The latter, in turn, are subdivided into:
1-P) natural disasters and natural disasters (earthquakes, tsunamis, volcanic eruptions, landslides, floods, natural fires, hurricanes, heavy snowfalls, avalanches, epidemics, mass reproduction of harmful insects, etc.) and
1-A) anthropogenic (man-made) disasters (industrial and communication accidents, explosions, collapses, destruction of buildings and structures, fires, etc.).
The greatest environmental hazard is presented by man-made disasters, which are accompanied by the release of harmful chemical and radioactive materials into the environment.
Excessive population density in many human populations is also a significant cause of environmental damage. The growth of the population and the density of human populations, along with the weakening of immunity (in the broadest sense of the word), have become the main internal factor in the vulnerability of huge masses of people. This applies almost without exception to all external factors affecting people - from unpredictable natural disasters or the emergence of a new deadly virus to carefully planned wars. Population migration to cities and to densely populated coastal areas exacerbates the situation.
Environmental damage caused by economic activity is not necessarily associated with accidents and disasters. They can be the result of incomplete or erroneous accounting of the environmental components of any territorial activity. The main ones are:
1) a significant excess of the maximum permissible technogenic load on the territory;
2) improper location of production, economic facilities, in which economic feasibility excessively prevails over environmental admissibility;
3) erroneous assessment of the ecological consequences of the location of productive forces and anthropogenic transformation of natural landscapes.
2.2 Diseases of civilization
Diseases of civilization are diseases and other injuries to people that have arisen as a result of the costs of industrial and scientific and technological revolutions, accompanied by deformation of the environment as a result of the destruction of natural ecosystems.
There are many direct causes of civilization's illnesses. The most serious phenomena are the disintegration of the human genome as a result of the destruction of its own ecological niche and the accumulation of a colossal genetic load, an increase in psychosocial stress, overnutrition, drug abuse, smoking, alcohol, and ever-increasing environmental pollution.
2.2.1 Tobacco smoking
In terms of scale and prevalence, it is the most dangerous of these causes. The leaves of tobacco contain nicotine - a strong poison, which in large doses leads to paralysis, respiratory arrest and cessation of cardiac activity.
Tobacco-related illnesses are such a major cause of health impairment and premature death in developed countries that control of cigarette smoking in these countries could do more to improve health and life expectancy than any other single intervention in any area of preventive medicine. ...
2.2.2 Addiction
Drug addiction is a disease of socially and genetically predisposed persons, characterized by an irresistible craving for drugs and a state of temporary or chronic intoxication of the body. The causes of the disease are socio-psychological factors.
The clinical picture of the action of opiates and cocaine is different, but the successive stages of the development of addiction are similar. At the first stage, feelings of "high", euphoria, and a sense of bodily comfort play a decisive role in "being drawn" into drug addiction. At the same time, resistance is growing: in order to induce euphoria, the doses must be increased by 2-3 times. The second stage of drug addiction is characterized by severe physical dependence. The growth of resistance to the drug is sharply expressed, the duration of action of even an increased dose is noticeably reduced, the previous "high" disappears, the drug becomes only a necessary doping to restore efficiency, vigor and appetite. Somatic ailments are aggravated. Skin flakes, hair splits, nails break, teeth crumble. Characterized by unusual pallor, anemia, and constipation. Sex drive fades away, impotence occurs in men, and amenorrhea occurs in women. Sexual activity can manifest itself only in a passive form, including homosexual, in the form of prostitution in order to obtain money for drugs. The likelihood of AIDS, viral hepatitis, and other diseases is sharply increasing.
The third stage of drug addiction is rare, since not all drug addicts live to see it. Extreme exhaustion, asthenia and apathy make the patient disabled. Interest is kept only in the drug. Death occurs from concomitant diseases.
2.2.3 Alcoholism
Alcoholism is a chronic disease characterized by a combination of internal and mental disorders, one of the most common substance abuse. The reason is the systematic abuse of alcoholic beverages containing ethyl alcohol. Typical signs of alcoholism: change in resistance to alcohol, pathological attraction to intoxication, the development of deprivation syndrome - alcohol withdrawal. The problem of treating alcoholism is largely associated with the development of means of suppressing the craving for alcohol.
The life expectancy of patients with alcoholism is shortened by 15-20 years due to the increased incidence of internal organs. The most serious losses are caused not so much by far-reaching alcoholism as by the systematic consumption of alcohol by people of working age and relatively healthy people, which significantly increases the number of road traffic accidents, family breakdowns, suicides and homicides on domestic grounds.
4 Noncommunicable diseases
4.1 Genetic load
Disabling the mechanisms of natural selection, advances in hygiene and medicine, saving many patients and transferring acute diseases to chronic forms; replacing the body's defenses with medicines and procedures, preserving the life of people with a burdened heredity, environmental pollution, stress, smoking, alcohol, drugs - all this did not contribute to the preservation of a healthy species gene pool.
Humanity has accumulated a dangerous genetic load due to mutations, most of which would not keep the axis if natural selection continued to act as it does in natural animal populations.
The number of identified forms of hereditary diseases and deviations increased
etc.................
Environmentally dependent diseases of the population include those diseases in the etiology of which environmental factors play a certain role. Often in this case, the terms are used: "ecological disease", "anthropoecological diseases", "ecologically dependent diseases", "ecopathology", "civilization diseases", "lifestyle diseases", etc. In these terms, the emphasis appears to be on the ecological or social causation of many diseases.
Depending on the nature (physical, chemical, biological, etc.), the environmental factor can play a different role in the etiology of the disease. It is able to act as an etiological, causal, practically determining the development of a specific specific disease. Currently, about 20 chronic diseases of the population are reasonably associated with the impact of environmental factors (Minamata disease, caused by the pollution of marine and river fauna with mercury-containing industrial effluents; Itai-itai disease, as a result of irrigation of rice fields with water containing cadmium, etc.)
If the environmental factor acts as the cause of the disease, then its effect is called deterministic.
An environmental factor can act as a modifying factor, i.e. change the clinical picture and aggravate the course of a chronic disease. In this case, the risk associated with a particular factor is modified depending on the presence of another factor or influence. For example, air pollution with nitrogen oxides provokes symptoms of respiratory tract dysfunction in patients with chronic respiratory diseases.
In some cases, the factor under investigation can have a mixing effect. An example of confounding factors is age and tobacco smoking when studying the effect of atmospheric pollution on the risk of developing respiratory diseases, smoking when studying the risk of developing lung cancer and pleural mesothelioma when exposed to asbestos, etc.
Diseases can also be caused by an imbalance between the internal and external environment of the body, which is especially characteristic of endemic diseases. The etiology and pathogenesis of some endemic diseases are well understood. For example, it was found that observed in many regions of the world fluorosis due to excessive intake of fluorides from drinking water; the occurrence of endemic goiter is associated with a lack of iodine in the environment and food and, in addition, may be the result of the action of certain chemicals that disrupt hormonal status.
The most characteristic signs of environmental, in particular chemical, the nature of the disease:
A sudden outbreak of a new disease. Often it is interpreted as infectious, and only a thorough clinical and epidemiological analysis can identify the true cause of exposure to chemicals;
Pathognomonic (specific) symptoms. In practice, this symptom is quite rare, since specific signs of intoxication are mainly manifested at relatively high levels of exposure. A certain combination of nonspecific symptoms has a much greater diagnostic value;
A combination of nonspecific signs, symptoms, laboratory data, unusual for known diseases;
Lack of contact transmission routes characteristic of infectious diseases. For example, people living in the same apartment with asbestos workers have a very high risk of developing tumors of the lungs and pleura, which is due to exposure to asbestos particles carried along with contaminated overalls;
A common source of exposure for all victims; the connection of diseases with the presence of chemicals in one of the environmental objects;
Detection of the dose-response relationship: an increase in the likelihood of developing a disease and / or an increase in its severity with increasing dose;
The formation of clusters (condensation) of the number of cases of diseases, usually relatively rare in the population;
Typical spatial distribution of disease cases. Geographic localization is characteristic, for example, of almost all endemic diseases;
Distribution of victims by age, sex, socioeconomic status, profession and other characteristics. The most susceptible to the disease are often children, the elderly, patients with one or another chronic pathology;
Identification of subgroups with an increased risk of disease. Such subgroups can often indicate the pathogenetic characteristics of the influencing factor;
Temporary relationship between disease and exposure to factors. It is necessary to take into account the possibility of a latency period ranging from several weeks (tricresyl phosphate - paralysis, dinitrophenol - cataract) to several decades (dioxins - malignant neoplasms);
The connection of diseases with certain events: the opening of a new production facility or the beginning of the production (use) of new substances, the disposal of industrial waste, a change in the diet, etc .;
Biological plausibility: the observed changes are confirmed by data on the pathogenesis of the disease, the results of studies on laboratory animals;
Detection of a test chemical or its metabolite in the blood of victims;
The effectiveness of interventions (specific preventive and therapeutic measures).
Each of the above signs individually is not decisive, and only their combination allows us to suspect the etiological role of environmental factors. This is the extreme difficulty of establishing the ecological nature of the disease of an individual person.
Population hygienic diagnostics is used to assess the environmental situation in various territories and identify health risks associated with certain hazardous enterprises or other sources of environmental pollution. A favorable ecological situation is understood as the absence of anthropogenic sources of adverse effects on the environment and human health and natural, but abnormal for a given area (region) natural climatic, biogeochemical and other phenomena. Depending on the intensity of the influence of environmental factors on the health of the population, zones of an ecological emergency situation and zones of ecological disaster are distinguished.
The ecological state of the territories is assessed by a set of medical and demographic indicators. These indicators include perinatal, infant (under 1 year of age) and child (at the age of 14) mortality, the frequency of congenital malformations, spontaneous miscarriages, the morbidity structure of children and adults, etc. Along with mortality and morbidity indicators, the average duration is analyzed life, the frequency of genetic disorders in human cells (chromosomal aberrations, DNA breaks, etc.), shifts in the immunogram, the content of toxic chemicals in human biosubstrates (blood, urine, hair, teeth, saliva, placenta, human milk, etc.).
Along with population hygienic diagnostics, there is also an individual one, aimed at identifying causal relationships between health disorders in a particular person and potentially harmful environmental factors acting or acting in the past. Its relevance is determined not only for the correct diagnosis, treatment and prevention of diseases, but also for the establishment of a possible relationship "environment - health" in order to determine material compensation for damage to human health as a result of environmental or industrial factors.
In terms of severity, possible health effects are divided into catastrophic (untimely death, reduced life expectancy, severe impotence, disability, mental retardation, congenital deformities), severe (organ and nervous system dysfunction, developmental dysfunction, behavioral dysfunctions) and unfavorable (weight loss, hyperplasia , hypertrophy, atrophy, changes in enzyme activity, reversible dysfunction of organs and systems, etc.).
As already noted, the reactions to external influences in the population in most cases are of a probabilistic nature, which is due to differences in the individual sensitivity of people to the action of the studied environmental factor. In fig. 3.9 shows the spectrum of the biological response of the population to the impact of environmental factors. As you can see from the picture,
in the largest part of the population, as a result of exposure to harmful factors, latent forms of diseases and prenosological conditions develop, which are not detected by mortality, seeking medical care, and hospitalized morbidity. Only a targeted and in-depth medical examination is able to assess the true state of health in the exposed population. This task is designed to solve hygienic diagnostics.
Hygienic diagnostics focuses on identifying pre-morbid (premorbid) conditions. The subject of research in hygienic diagnostics is health, its magnitude. It is carried out by a doctor in order to assess the state of the adaptive systems, early detection of stress or disturbance of adaptive mechanisms, which in the future can lead to illness. The doctor cannot and should not calm down even when the patient comes with certain complaints, but it was not possible to find objective signs of the disease in him. Such people (unless they are explicit simulators) should be referred to the risk group (observation) and their health status should be studied in dynamics.
Classification of carcinogens (IARC)
1 - known human carcinogens; 2A - probable human carcinogens; 2B - possible carcinogens;
3 - agents not classified as carcinogenic;
4 - agents, probably not carcinogenic to humans.
For many types of malignant neoplasms, preventive measures are extremely effective. According to the WHO, preventive measures can reduce the risk of developing stomach cancer by 7.6 times, colon cancer by 6.2 times, esophagus by 17.2 times, and bladder cancer by 9.7 times. About 30% of all deaths from all types of malignant neoplasms and 85% of cases from lung cancer are associated with smoking.
Such a wide range of chemical factors and industries (far from complete!) Requires the doctor to have an idea, at least within the framework of this list, of the possible risk to his patients and focus on the earliest signs of possible ill health in people.
