SECTION 2 

 TOXICOLOGICAL CONTROL OF POLLUTION OF FRESHWATERS 



N.S. Stroganov 



The methods of chemical, microbiological and sanitary/hydrobiological 

 analysis have been well established for the evaluation of water quality. 

 Each of the methods allows the characterization of water in any single 

 aspect, i.e., chemical, epidemiological or sanitary significance. 



At the present time, various toxic substances such as petroleum and 

 its associated products, pesticides, heavy metals, detergents, metal 

 organic compounds and many others are discharged into surface waters in 

 ever growing amounts. The toxic substances impart an altered quality to 

 the receiving waters, to which the aquatic organisms react with extreme 

 sensitivity, but which is not evaluated by the methodology noted earlier. 

 Thus, toxicology evaluations of water quality are required. 



As industry develops, and as chemistry advances in various fields 

 related to the economy, the increasing potential for pollution of the 

 water requires the organization of toxicologic control of waste waters to 

 assure continued quality of all large water-bodies and to provide more 

 reliable protection for these surface waters. Using integrated models, 

 toxicological control must characterize the quality of water in relation 

 to the suitability for the life of aquatic organisms, it is expedient to 

 exercise control of the toxicity of waters in two ways: 



1. Evaluation of the toxicity of waste waters discharged 

 from industrial sources, sewage plants, and points of 

 population concentration, and 



2. Evaluation of the toxicity and associated hazards of 

 waters for aquatic organisms. 



These varieties of control characterize both the quality of waters 

 entering a water-body and the waters of the reservoir itself in which the 

 self-purification has already begun or become pronounced. The essence of 

 such toxicological control may be divided into two categories as follows: 



The First Variant 



Three organisms having varying degrees of sensitivity are suggested 

 for testing for acute toxicity: waterfleas [Vaphvua magna, Straus) as a 



