2 BULLETIK" 369, U. S. DEPAETMEXT OF AGEICULTUEE. 



cent) desired no rigid standard; only one desired a standard of no 

 B. coli in 10 cc quantities; thirty-five (85.4 per cent) desired to apply 

 the Hygienic Laboratory standard or one more rigid; eight (19.8 per 

 cent) would tolerate no B. coli in bottled waters; one of the five bac- 

 teriologists desiring no rigid standard considered water to be suspi- 

 cious if three 10 cc portions show B. coli. 



We have a right to demand that bottled water shall first of all be 

 clean. Wliatever other quahties it may claim or offer are secondary 

 to cleanUness. In a study, therefore, of the bacteria found, we have 

 a right to consider them not only as possible evidences of danger to 

 health but as indices of conditions in the bottling room for which 

 the operator is clearly responsible. 



SIGNIFICANCE OF BACTERIA IN POTABLE WATERS. 



It is understood that natural waters may contain bacteria which 

 multiply in the presence of very small amounts of organic matter. 

 Bacteriologists who have worked with chstiUed water are famihar 

 with the micrococci which multiply rapidly therein when the per- 

 centage of organic material is extremely low. The presence, there- 

 fore, of a large number of organisms in waters which have been 

 bottled for several days or weeks has little significance unless the 

 characters of these organisms are more or less definitely known. 



The presence of B. coli in large numbers in waters is universally 

 considered as an mdication of the possible presence of its dangerous 

 associates. The conditions under which waters are bottled and 

 held and the mineral substances present ni&j, in some cases, exert 

 influences upon the multiplication of B. coli differing slightly from 

 the effect of surface or well waters in nature. Preliminary studies 

 in this laboratory indicate an immediate decrease instead of any 

 possible increase of B. coli in freshly inoculated bottles of certain 

 spring waters.^ Houston ^ found that B. coli disappeared in stored 

 water from the River Lea. Dunham ^ observed that distilled water 

 enriched with either hay infusion or nutrient broth (1 cc in 1 liter) 

 and inoculated with over 20,000 B. coli showed a marked reduction 

 of the total number of B. coli at the end of 24 hours. He also reported 

 that sterile water inoculated with pollution from ordinary soil does 

 not show an appreciable number of B. coli. 



It may, therefore, be assumed that bottled waters in which B. coli 

 are found in appreciable numbers contained approximately all of 

 those B. coli (if not more) when they left the springs or bottling 



1 Browne, W. W. (Jour. Infect. Dis., v. 17, No. 1, 1915, pp. 72-78) finds multiplication of 5. coli in stored 

 water, but an analysis of his experiments shows that the water used was so enriched as to be no longer 

 comparable to stored spring waters. 



2 Houston, Reports on Research Work, Metropolitan Water Board, London, 1907. 



3 Dunham, E. K., Value of bacteriological examination of water from a sanitar}' point of view, Jour. 

 Amer. Chem. Soc, v. 19, No. 8, 1897, p. 591. 



