Agriculture Reference
In-Depth Information
21.1 INTRODUCTION
Current ecological situation in Ukraine is characterized by a considerable anthropo-
genic burden in the form of mutagens of physical and chemical nature. Total xenobi-
otic contamination of atmospheric air, soil, drinking water, and foodstuff was caused
by genetically explained pathology; the latter leads to birth defects of the development
and cytogenetic disorders in gametal and somatic cells [1, 2].
One of the main contaminants of the biosphere of industrial cities is heat power
engineering; its share is 27-32 percent of the total volume of contaminating emissions;
recently, they have been 100 million (metric) tons [3]. Thermal electric stations emit
mutagens into free air, including heavy metals, radioisotopes, benz(a)pyrene, dioxins,
and other chemical carcinogens [4]. The analysis of the contaminating sources con-
fi rms that the major contaminant of the biosphere with heavy metals, which comes
in an aeroindustrial way, is thermal power station (TPS); their emissions contain Cu,
Zn, Pb, As, Hg, Ni, V, Cr, and Al [5]. Despite the fact that they play an active role in
biochemical reactions in trace amounts, they are toxic and capable of reducing natural
resistance of biological objects to biotic and abiotic factors of the environment when
they are in large amounts [6]. The most important depositor of heavy metals both in
natural and artifi cially created ecosystems is soil. Heavy metals stay much longer in
the soils than in other natural bodies. Thus, conditionally the soil contamination with
heavy metals can be considered “everlasting” (metals are not destroyed; they shift into
another form of existence, including the composition of salts, oxides, and metalor-
ganic compounds). The period of semiremoval for copper is 310-1,500 years, for zinc
is 70-510 years, for lead is 740-5,900 years, and for cadmium is 13-110 years [7].
TPS as compared with properly functioning nuclear power stations are more dan-
gerous sources of radiation contamination, because additional radiation doses, which
people who live near TES receive, are 40 times higher than those caused by nuclear
reactors [8-10]. Cytogenetic studies of the lymphocytes of peripheral blood of the
workers of Kemerovska TPS (Siberia) showed certain increase of chromosome aber-
ration frequency when compared to a control group [11]. The highest chromosome
aberration frequency was typical for the workers of the chemical workshops, and was
lowest for the workers of the repair shops.
The coal used at TPS contains a relatively small quantity of primary radionuclides:
on average, potassium—40-50
Bq
/
kg
, uranium-238 and thorium-232—20
Bq
/
kg
, and
its contribution to a radiation dose of people is relatively small. Disproportionation/
redistribution of radionuclides from the ground into a biosphere takes place during
coal getting and burning, and using coal ash for building materials, which explains
radiation increase of the population [8].
Solving ecological problems concerning environmental pollution with TPS emis-
sions requires the development and application of the monitoring system of different
kinds in the areas adjacent to stationary sources of thermal power engineering. Most
of the research is aimed at studying the accumulation level of heavy metals, [12] ra-
dioisotopes [13] in the soil, water reservoirs, and plants depending on the distance to
the pollution source. Genetic studies are very important in the system of biological
monitoring, as they make possible the evaluation of consequences of the simultaneous
effect of several stress factors for the consecutive generations at cellular and molecular
Search WWH ::
Custom Search