46 SHELLFISH CONTAMINATION FROM SEWAGE-POLLUTED WATERS. 



exposed to conditions favorable to fecal contamination. Occasion- 

 ally data in regard to the probable sources of pollution of a given 

 food product can not be obtained, but as the work progresses and 

 opportunity is afforded to study these problems from various points 

 of view, it becomes more apparent that the colon test is invaluable as 

 an index of pollution 



Aside from being a mere indication of existing danger from sewage 

 pollution, the colon bacillus is fast assuming the role of a pathogenic 

 organism. Various intestinal derangements and other visceral dis- 

 orders are now ascribed to B. coli infection. In a recent article 

 Thompson 66 presents evidence substantiating the relationship of 

 B. coli to certain pathological processes of the abdomen, such as 

 appendicitis. Under normal conditions the colon bacillus appears 

 to exist as a harmless organism in the intestinal tract, but in the pres- 

 ence of irritating substances or under abnormal putrefactive and 

 fermentative conditions this bacillus seems to become an active factor 

 in the causation of disease.. The author has recovered a virulent 

 strain of the colon bacillus and reproduced fatal infections in dogs, 

 cats, guinea pigs, and pigeons. These results usually resulted from 

 inoculating the animals with small quantities of a 24-hour bouillon 

 culture, although in some cases infection was brought about by 

 feeding material infected with the organism. The colon bacillus 

 probably plays a further role as a pathogenic organism by producing 

 toxins in albuminous food materials of a highly perishable nature. 

 In such a product as shucked oysters, if there is a high bacterial count 

 with thousands of B. coli present per cubic centimeter of the oyster 

 liquor, it is highly probable that toxic substances have already been 

 elaborated. With the consumption of such material gastroenteritis 

 to some degree must invariably follow. Undoubtedly many obscure 

 cases of ptomain poisoning and other intestinal disorders of lesser 

 magnitude could be ascribed to eating tainted food, especially if the 

 substances are rich in albumin and bacterial activity has appreciably 

 developed. 



In summarizing her work on the chemistry of the colon bacillus, 

 Leach 40 gives the following analysis, showing the presence of toxins 

 together with other complex substances in the cell of the colon 

 bacillus : 



Elementary analyses show that age, conditions of growth, and especially the com- 

 position of the nutrient medium cause bacteria of the same strain to differ widely in 

 elementary composition. Proteid, nucleo-proteid, nucleic acid, protamin, fat, wax, 

 lecithin, glycogen, and other carbohydrates have all been reported as obtained from 

 the bacterial cell in varying degrees of purity. Cellulose seems to be present in cer- 

 tain species, but by no means in all. Besides the preparations mentioned above, 

 crystalline compounds have been prepared and purified, proving the presence in the 

 cell of xanthin bases, pentose, fatty acids, and perhaps thymin and uracil, toxins, 

 enzyms, and agglutinins have been split off from the cell, but more progress has been 

 made in determining their physiological action than their chemical nature. 



