Xenobiotic

Xenobiotics (from the Greek. Ξένος - alien and βίος - life) is a conditional category for the designation of chemicals alien to living organisms that are naturally not included in the biotic cycle. As a rule, an increase in the concentration of xenobiotics in the environment is directly or indirectly associated with human economic activity. In some cases, these include: pesticides , some detergents ( detergents ), radionuclides , synthetic dyes , polyaromatic hydrocarbons, and others. Once in the environment, they can cause an increase in the frequency of allergic reactions, death of organisms, change hereditary traits, lower immunity , disrupt metabolism , disrupt the processes in natural ecosystems up to the level of the biosphere as a whole.

The study of xenobiotic transformations by detoxification and degradation in living organisms and in the environment is important for the organization of sanitary-hygienic measures for the protection of nature.

Content

Xenobiotic Action

Xenobiotics - any substances alien to the body that can disrupt the flow of biological processes. In most cases, xenobiotics, getting into living organisms, either have various direct undesirable effects ^[1] , or form toxic metabolites due to biotransformation, causing:

toxic or allergic reactions
changes in heredity
decreased immunity
specific diseases ( Minamata disease, itai-itai disease , malignant tumors )
metabolic distortion, disruption of the natural course of natural processes in ecosystems, up to the level of the biosphere as a whole.

The study of the influence of xenobiotics on the immune system is carried out by immunotoxicology .

Xenobiotic Examples

heavy metals ( cadmium , lead , mercury and others)
freons
petroleum products ( benzene , toluene , xylene mixtures, diesel fuel, etc.)
polycyclic and halogenated aromatic hydrocarbons
pesticides
many types of plastics
synthetic surfactants ^[2]

Most xenobiotic substances can be found in nature. So, dioxins are formed as a result of natural processes, such as volcanic eruptions and forest fires ^[3] . Many substances can be classified as xenobiotics if they accumulate in the environment at unnaturally high concentrations during industrial production or waste disposal.

Xenobiotics as Contaminants

Contaminants are a special case of xenobiotic substances, and penetrate the human and animal body exclusively by alimentary route, i.e. through food products. This group includes a huge number of different xenobiotics.

Many contaminants pose a great danger to human health or life, due to high biological activity, and therefore control over the quality and safety of food is necessary.

Biotransformation

Lipophilic xenobiotics currently attract particular attention of ecologists and toxicologists, since, accumulating in fatty tissues, they are able to pass along the food chain into animal and human organisms, turning into more polar and, therefore, more easily absorbed or excreted substances.

Notes

↑ Rand G., Petrocelli S. Fundamental of Aquatic Toxicology. New York et al .: Hemisphere Publishing Corporation, 1985, 666 p. ISBN 0-89116-382-4 .
↑ Biological effects of surface-active substances on organisms. - M .: MAX-Press. 2001.334 s. ISBN 5-317-00323-7 .
↑ World Health Organization . Fact sheet N ° 225, May 2014 Dioxins and their effects on human health.

[1] Rand G., Petrocelli S. Fundamental of Aquatic Toxicology. New York et al .: Hemisphere Publishing Corporation, 1985, 666 p. ISBN 0-89116-382-4 .

[2] Biological effects of surface-active substances on organisms. - M .: MAX-Press. 2001.334 s. ISBN 5-317-00323-7 .

[3] World Health Organization . Fact sheet N ° 225, May 2014 Dioxins and their effects on human health.