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SZAKMAI - TUDOMÁNYOS ROVAT

Stahl, F.W. (1987): A kromoszómák közötti újra-
rendeződés. Tudomány a Scientific American
magyar kiadása. III. évf. 4., 44 – 56

Stringfellow,W.T. – Alvarez-Cohen, I (1999): Eva-
luating the relationship between the sorption of
PAHs to bacterial biomass and biodegradation.
Water Research, Vol.33, No.11, 2535 – 2544

Tabair, H.H. – Ouave, S.A. – Mashni, C.I. – Barth,
E.F. (1981): Biodegradability stuies with organic
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Weber, W.J. – Jones,Jr. B.E. – Katz, I.E. (1987):
Fate of toxic organic compounds in activated
sludge and integrated PAC system. Water Sci-
ence and Technology, Vol. 19, Numb.3/4, 471
– 482

Summary

The wide variety of toxic organic compounds substance is greater than the value I* the bio-
(hydroxyl-, halogen-, and nitro-, amino-, ar- degradation efficiency will be reduced and ef-
omatic and aliphatic derivatives) is in the or- fluent wastewater quality greatly deteriorates
ganic chemical and pharmaceutical effluents. (figure 2).
The last 100 years, due to development of
high degree of chemical substances in waste The toxicity of industrial discharges to micro-
water have been emerged which can’t occur organisms is measured by respiration inhibi-
in nature. These materials are usually very dif- tion. The toxic effect reducing or eliminating
ficult to degrade and in many cases the toxic of toxic substances increasing the sludge-age
effects on activated sludge system. The toxic when the two-stage biological wastewater
substances in the biological treatment-system treatment, oxidation methods, adsorbents
are generally not cause irreversible inhibition. (activated carbon, activated zeolites, clays and
natural clay-minerals) and the use of com-
The bacterial degradation and detoxification plex-forming agents (beta-cyclodextrin) may
of toxic compounds requires the production be considered. Efficient techniques for the
of enzymes that are capable of recognizing removal of highly toxic organic compounds
and converting compounds which do not from water and wastewater have drawn sig-
occur at significant concentrations in nature. nificant interest. Adsorption is recognized as
Because that biodegradation be effective the an effective and low cost technique for the
concentration of the toxic substance should removal of organic pollutants from water and
be kept below the critical value (I*). Other- wastewater, and produce high-quality treated
wise, if the effluent concentration of the toxic effluent.

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