Toxic Pollution 141
Agriculture is such an example that upsets the balance between plants or
between plants and animals.
There are millions of species of fungi and other microorganisms, but only
around 200 species cause serious damage to agriculture. In nature there is
a complex web of relationships between plant and animal organisms and
turbed by monoculture in large areas, where an unnatural, unstable environment is created. The new conditions of life usually favour the excessive
proliferation of one or more microorganisms which harm the specific crop.
Without predators or competitors, such parasites will easily predominate and
cause great damage, and therefore it becomes necessary to combat them.
This is theoretically possible using various biological or physical/chemical
means, but in modern-day intensive farming the means used are almost
exclusively chemical, the so-called pesticides, which contain various biocides that target parasites, bacteria, fungi, weeds, insects, mites, nematodes,
rodents, etc. Certain biocides, such as antibiotics, are also used in intensive
livestock farming. Other chemical products used in intensive farming and
animal production are various food additives such as hormones.
The biocides are a large group of synthetic organic compounds which are
toxic to some categories of organisms and are used in intensive agricultural
production as well as in homes and gardens. Their use and applications
have grown by leaps and bounds in recent decades and have increased the
output of cultivated land many times over, by significantly helping to eliminate harmful insects, parasites and weeds. They may be classed in various
chemical groups, depending on the active substance they contain, including
the following:
• Chlorinated hydrocarbons
• Organophosphate esters
• Carbamic and aliphatic acids and their esters
• Compounds of chlorotriazines and aminotriazines
• Compounds of the urea group
• Pyrethroids and natural pyrethrins
• Pheromones
• Inorganic salts of As, Zn, Cu etc.
Global industry produces thousands of different pesticide products by
combining around 1100 active chemical ingredients. In recent years, with
better methods of cultivation and automation, the use of pesticides has
increased substantially.
After their application to plants or to the soil, pesticides undergo a series
of physical, chemical and biological processes (hydrolysis, oxidation, fission ,
transport, evaporation, uptake by plants, etc.). They gradually pollute the
ground, the water of rivers, lakes and seas, and from time to time appear
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