ANTAGONISM AND ITS POSSIBLE UTILITY IN 

 POLLUTED WATERS 



By Edwin B. Powers 



University of Nebraska, Lincoln, Nebr. 



During the past few years much has been said and written 

 about the pollution and contamination of streams, especially 

 as its bears upon the problem of the perpetuation of our most 

 important food fishes. Much injury and destruction of food 

 fishes is caused, for instance, by the ill-considered methods 

 of factories of getting rid of by-products. These pass un- 

 heeded by the general public, and the protest of those most 

 interested is often ineffective. Frequently the money spent 

 to improve the condition serves only as a sedative for the 

 public conscience. In most cases this is not intentional but is 

 the result of ill-directed remedial measures. 



The first thought is to add something to the stream that 

 will counteract the harmful effects of the contaminating prod- 

 ucts. This is suggested by the work that has been done on 

 antagonistic substances. Experiments presented in this paper 

 suggest the possibility that under certain conditions the addi- 

 tion of an antagonistic substance to a polluted stream might 

 prove detrimental rather than beneficial — might tend to accen- 

 tuate rather than counteract the toxic element. For this 

 method to be most effective, great care must be exercised in 

 determining the exact quantity of the remedial material or 

 materials that should be added so as to be most efficient. 



A few experiments were run with calcium chloride and 

 sodium chloride in connection with the work on toxicity of 

 salts to fish (Powers, 1920) to ascertain if there is any rela- 

 tion between the antagonism and the toxicity curves of these 

 two salts. Through these experiments it was hoped to throw 

 some light on the method of treatment of polluted streams. 



A 0.297 N. calcium chloride solution, to which varying 

 amounts of sodium chloride were added, was used for testing 



'Contribution from the Zoological Laboratory, University of Illinois, No. 179. 



