2 ОРГАНИЗАЦИЯ И МЕТОДИКА РАБОТ - Courrier international

introduction of a methyl substituent at position 5 and disappeared after the introduction of two
methyl groups. While acene hydrocarbon (naphthalene, anthracene) and anthanthrene activity
significantly increases after the introduction of two methyl substituents at position 2 and 6. It should
be stressed that the products of PAH degradation in the environment can have even stronger
oncogenic effect than initial substances under the influence of physico-chemical and
microbiological factors, however, the monitoring of these PAH compounds and metabolites is a
quite complex task is not practically carried out now.
Organochlorine compounds
Organochlorine compounds (OCC) are not typical for the nature; they are strictly of anthropogenic
origin. OCC are the most hazardous group of persistent organic pollutants and are characterized by
low water solubility (about 0.5 - 0.001 mg/l) and high lipid solubility and low solubility in organic
solvents and lipids lipophilicity, low vapor pressure (10 -3 - 10 -5 at 20° C) and exceptional
microbiological, chemical and thermal stability.
The main persistent organochlorine compounds in the environment are organochlorine pesticides of
various kinds (hexachlorocyclohexanes, DDT and its isomers, metabolites and by-products,
polychlorocyclodienes, polychlorobenzenes, herbicides and defoliants based on 2,4-D acid and
polychlorinated phenols) polychlorinated biphenyls (PCB) as well as polychlorodioxines and
polychlorobenzofurans that have never been produced as chemical synthesis products, but have
been introduced into the environment either as admixtures of other compounds or have been formed
due to the burning of garbage, fires at plants producing chlorine-containing plastics, transformation
of waste of paper and other material bleach.
Polychlorinated biphenyls
The group of polychlorinated biphenyls (PCB) includes 209 related compounds (known as
congeners) which are the products of chlorination of diphenyl (biphenyl) and differ only in the level
of substitution and mutual location of substituents.
The characteristic feature of PCB production is that it is not oriented towards the production of
separate compounds by means of direct chlorination of diphenyl but their mixtures of complex
composition determined by the conditions and duration of the production process. Such mixtures
could contain from 20 to 71 weight percent of chlorine, and its content was usually reflected in the
trade name of the product by some means or other.
Decachlorobiphenyl, a product of complete chlorination of diphenyl, was the only substance to be
specially produced for the use as casting wax. Small quantities of PCB can be formed as by-
products of some types of chemical synthesis during chlorination of water and thermal cracking of
chlorine-containing organic substances.
PCB mixtures have unique physical and chemical properties determining their wide use in the
industry. They are as follows: nonflammability, resistance to acids and alkalis, oxidation and
hydrolysis, low solubility in water, thermal resistance, wide range of dielectric characteristics and
low vapor pressure at room temperature. The products synthesized and implemented as complex
mixtures of polychlorinated biphenyls are liquids in a very wide range of temperatures (from 50°
to 300° C).
FINAL REPORT for Contract No. CS-NPA-Arctic-13/2009 of December 01, 2009 within the framework of pilot project Development of
Technology of clean up of the area of Decommissioned Sites of The Russian Federation Ministry of Defense in the Arctic by the
Example of Alexanra Island of Franz Josef Land Archipelago from Hazardous Waste
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