IMMUNOLOGY TEXTBOOK - Mercury Podillya 2013

IMMUNOTOXIC IMPACT OF ENVIRONMENTAL FACTORS ON THE HUMAN BODY

One of the defining features of modern times is the intensive development of industry and nuclear power, the combustion of vast amounts of fuel, the excessive use of pesticides and herbicides in agriculture, and the unsustainable exploitation of all types of natural resources, which relentlessly drives environmental pollution (Table 93). The consequences of this process pose a hazardous threat to human life and health, as well as to flora and fauna.

Table 93. Major anthropogenic sources of environmental pollution in Ukraine

The consequences of anthropogenic environmental pollution include the accumulation of inert and chemically active substances in the environment, high levels of radioactive contamination by radionuclides across vast areas of Ukraine (5 million hectares), elevated Background radiation in the waters of the Dnipro, Prypiat, and Kyiv Reservoir, intense electromagnetic impact, and disruptions to natural landscapes driven by human activity.

Anthropogenic industrial and environmental pollutants (xenobiotics), depending on the duration and intensity of exposure as well as the aggressiveness of the factor itself, can exert immunosuppressive effects, trigger neurological, psychiatric, allergic, pseudo-allergic, and toxic-allergic reactions, provoke The Development of oncological and autoimmune diseases, cause growth disorders and fetal developmental anomalies during intrauterine life, and even have fatal consequences for The Human Body.

Currently, approximately 10 million chemical compounds are known, roughly 70,000 of which are listed in the International Register as toxic and about 1,000 as highly toxic compounds. Around 1,500 substances are used in pesticides, 4,000 in Pharmaceuticals, and 5,000 in food additives (according to B.M. Pukhlyk, 2002). In daily life, contacts with fuel combustion products, paints, pesticides, and similar agents occur most frequently. Social factors, such as stress, poor Nutrition, irregular work and rest schedules, lack of Sleep, and others, are of additional and equal importance.

Environmental Factors affecting the human immune system can be divided into the following groups:

Abiotic factors – Temperature, barometric pressure, humidity, daylight duration, magnetic field activity, and The chemical composition of air, soil, and water.

Biotic factors – microflora, flora, and fauna.

Anthropogenic factors – physical (electromagnetic waves, ionizing radiation, noise, vibration, ultrasound, ultraviolet radiation); chemical (harmful emissions from industrial plants and transport, occupational, domestic, and agricultural exposure to chemicals); biological (waste from biological preparation and food Processing plants); socio-domestic and socio-ecological (demographic shifts, urbanization, population migration, changes in diet and living conditions, psychophysiological overload, and inappropriate medical interventions).

According to the Classification by V. Wagner and V. Wagnerova, immunotropic chemical compounds can be divided into the following groups:

Products of complete and partial combustion of organic fuel: fly ash, toxic radicals and nitrogen peroxides, sulfur dioxide, carbon monoxide, and polycyclic aromatic hydrocarbons (benzpyrenes, benzanthracenes, cholanthrenes).

Chemical industry products: benzene, phenols, xylene, ammonia, formaldehyde and its resins, plastic processing and synthesis products, rubber and paint industry products, and petroleum products.

Household and agricultural chemicals: pesticides, insecticides, herbicides, fertilizers, food additives, detergents, cosmetic and food colorants, and cleaning agents.

Metals: lead, mercury, cobalt, and molybdenum.

Inorganic dust: silicon dioxide, asbestos, carbon, talc, polymetallic aerosols, and welding aerosols.

Biological pollutants: plant pollen allergens, microscopic mites, Fungi, Viruses, Bacteria, and parasites.

Pharmaceuticals (non-immunotropic drugs) are classified into a separate group of substances capable of exerting an immunotoxic effect.

Table 94. Immunological disorders caused by environmental and industrial factors

Xenobiotics exert diverse effects on the Cells and Organs of The Immune System (genotoxic, enzymotoxic, mutagenic, membranolytic). Among the most common alterations are Gene Mutations in specific somatic cells (lymphocytes and thymocytes), which may cause serious future abnormalities in the body's immune function (so-called "minor" defects).

Impairment of the structural integrity and functional activity of the immune system can drive the development of other pathologies, specifically predisposing individuals to acute and chronic infectious diseases, complicating the course of existing chronic conditions, promoting frequent relapses, and diminishing the efficacy of specific treatments and preventive measures.

Depending on the MECHANISM OF ACTION and the target of injury, xenobiotics can induce immune system dysfunction, the development of acquired immunodeficiencies, autoimmune and oncological diseases, as well as allergic, toxic-allergic, and pseudo-allergic pathologies.

Immunotoxic Effects of Medications

The following medications exhibit a pronounced immunosuppressive effect:

Radiation therapy;

cytostatics;

immunosuppressants;

glucocorticosteroids;

antibacterial drugs (Penicillins, chloramphenicol, Tetracyclines, streptomycin, rifampicin);

sulfonamides;

isoniazid;

antifungals;

nonsteroidal anti-inflammatory drugs;

antihistamines;

neuroleptics;

benzodiazepine tranquilizers;

tricyclic antidepressants;

anticonvulsants.

The most frequent mechanisms mediating the immunosuppressive action of pharmaceuticals include:

- reduction of the phagocytic activity of macrophages and neutrophils;

- modification of lymphocyte membranes;

- action of blocking factors (immune complexes in which the drug acts as a hapten bound to a carrier protein);

- impairment of T-lymphocyte maturation and their effective cooperation with B-lymphocytes during the Immune Response;

- reduction of antiviral immunity through decreased cytotoxicity of T-lymphocytes and natural killer cells;

- defects in The formation of the primary immune response (suppression of B-lymphocyte blastic transformation and antibody production).

Human immune status can be altered by environmental factors. In general, these factors can be divided into 2 groups:

physiological: dietary patterns, physical exertion, and climatic-geographical influences);

non-physiological (hypothermia, anthropogenic factors such as chemicals, fuel combustion products, radiation, dust, etc.).

The intensity and duration of these factors are of critical importance to the Organism. For example, excessive Muscle strain may prove non-physiological, whereas the body can adapt to low doses of environmental pollutants. Typically, severe stress loads that lead to the failure of adaptive systems cause more significant changes in immune response parameters. All these alterations are individual, and their nature depends on multiple factors, including the genetic CHARACTERISTICS OF THE organism.

Examinations of large groups of workers across various industries (metallurgy, radio engineering, chemical production, livestock farming, etc.) have established that all groups exposed to anthropogenic factors exhibit stage-specific characteristics in their immune status.

The First stage is characterized by an elevated level primarily of IgA, while the Second Stage shows an elevation in all Ig levels. These stages typically lack clinical manifestations. As the Third Stage develops, the levels of all immunoglobulin classes either return to normal or decrease. The most distinct feature of the third stage is a reduction in T-helper lymphocytes (CD4+). Such immunological changes may serve as indicators of emerging immune dysfunction, which clinically manifests as an infectious syndrome with certain specific features:

a high frequency of opportunistic Infections caused by conditionally pathogenic microorganisms;

a tendency toward a prolonged course of infectious processes (extended persistence of pathogens) within the body;

the presence of a significant group of frequently and chronically ill children among the pediatric population of a given industrial region.

With the progression to the Fourth Stage, There is a further decline in immunoglobulin levels and CD4+ cells.