where: 



V 

 (A+S) 



rate of consumption of a substance (ug 1/hr), 



radioactivity of microorganisms in the whole sample, 



quantity of organic matter in the sample: 



A - added into the sample, 



S - found on the graph (yg/1), 



radioactivity of the added substance, 



time of incubation. 



This method may be used not only for the determination of the activity 

 of microflora, but also for the reserves and the rate of consumption of 

 separate toxic substances. For example, this technique was applied for 

 determination of the content and the rate of consumption of phenol in water, 

 Figure 5 shows the results of one experiment on the reserves of phenol in 

 the water of the Kamskoe reservoir. The points fit a linear progression 

 which cults off a segment of the abscissa equal to 13 mg/1 C of phenol. 



This method may also be used for the analysis of other organic toxi- 

 cants. It is necessary only to have a corresponding 1 ^C— 1 abel ed subbstance, 



REFERENCES 



Alekin, O.A. 1954. Chemical analysis of inland waters L. 



Kholodnyi, N.G. 1957. On the methods of quantitative studies of bacterial 

 plankton. Izbrannye trudy, Kiev, 3. 



Kuznetsov, S.I. 1952. Role of microorganisms in circulation of matter in 

 lakes. M. 



Kuznetsov, S.I. and G.S. Karzinkin. 1930. Method of estimation of bacteria 

 in water. Russ. gidrobiol. zh., 9. 



Kuznetsov, S.I., and V.I. Romanenko. 1963. Microbiological study of 

 inland waters. M.-L. 



Kuznetsov, S.I., V.I. Romanenko and N.S. Karpova. 1966. Number of bacteria 

 and production of organic matter in the water of the Rybinskoe Reser- 

 voir in 1963 and 1964. In Production and Circulation of Organic Matter 

 in Organic Matter in Inland Waters, M.-L. 



Lapshin, M.I. 1962. Working out the method of purification of waste 

 water. M. 



Lebedev, A.F. 1952. About assimilation of carbon by saprophytes. Izvest. 

 Donskogo gos. un-ta, 3. 1921, (Cited in Shaposhnikov V. M. Carbonic 

 Acid in Metabolism of Heterotrophic Bacteria. Mikrobiol., 21:6. 1952). 



Omelyanski, L.V. 1940. Manual on microbiology. M.-L. 



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