2 ОРГАНИЗАЦИЯ И МЕТОДИКА РАБОТ - Courrier international

personnel with the simultaneous decrease of one-time concentrations in atmospheric air and leading
to the chronic nature of soil (ground) water contamination with this group of pollutants.
Polycyclic aromatic hydrocarbons (PAH)
The sources of PAH intake into the environment can be divided into anthropogenic and natural
ones. The natural sources are volcanic outbursts, hydrocarbon anomalies in tectonically active
zones, endogenous geological processes, hydrothermal sources, hydrocarbon fluxes from gas and
oil, coal and shale fields, synthesis of PAH in old and modern sedimentary rocks and forest fires.
The natural processes leading to the formation of PAH in such a way can be related to the synthesis
without the participation of biomass at high (1000 °C and higher), medium (400-500 °C) and low
(100-150 °C) temperatures and with the conversion of the components of buried biomass in
sedimentary rocks in thermal catalytic reactions at temperatures from 80 to 200 °C.
The main anthropogenic sources of PAH are related to various production processes, among which
more than half of emissions come from power generation (due to incomplete combustion of organic
fuels such as coal, oil products and woods. Also coke-chemical and oil processing plants and
exhaust gases from vehicles make a significant contribution to the total PAH content.
It should be noted that the qualitative composition and structure of PAH from natural abiogenic
sources do not differ from those of anthropogenic origin if they are formed as a result of the high
and medium temperature processes while the low temperature conversion of organic matter leads to
the formation of aryl and alkyl substituted hydrocarbons with a large number of substituents in the
aromatic ring and with long-chain branchings.
Among PAH formed during combustion process, the compounds without substituents in the
aromatic ring such as phenanthrene, fluoranthene, pyrene, chrysene, benzpyrenes and
dibenzpyrenes are dominant, while the content of monomethyl substituted homologs is 3-10 times
lower. The ratio of specific PAHs in combustion products does not vary significantly during the
transition from one source to the other, at the same time, the prevalence of specific compounds can
be explained by their higher thermodynamic stability.
The composition of polycyclic aromatic hydrocarbons of coal and oil origin differs from that of
pyrolytic PAHs. In PAHs from coal fields and crude unfractionated oil, methyl derivatives of
naphthalene, phenanthrene and chrysene prevail, while in unsubstituted PAHs phenanthrene and
perylene. When hydrocarbons of natural origin are dispersed, PAHs can be directly discharged into
ecosystems by means of both their migration and migration of more light hydrocarbons with their
further transformation to PAHs in the presence of natural catalysts
The study of trace amounts of PAHs in environmental objects is of great significance due to their
relatively high chemical stability and high toxicity manifesting in their oncogenic, mutagenic and
teratogenic effects and a capability to cause poisoning and disorder of the immune system when
accumulating in organisms. Complex toxic effect on the organism allows to consider PAH to be the
agents that transform biosphere, at the same time their effects are reflected both in current and
future generations
Among detectable PAHs, benz(a)pyrene and dibenz(a,h)anthracene have the strongest oncogenic
properties; during laboratory experiments, tumors appeared even in breed from infected species.
The presence of alkyl substituents in the aromatic ring can both increase and decrease oncogenic
activity of PAHs. For example, 3.4-8.9- and 3.4-9.10 dibenzpyrene activity decreases after the
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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