42 SHELLFISH CONTAMINATION FROM SEWAGE-POLLUTED WATERS. 



report was absolutely false and the death certificate gave the cause 

 as " cerebrospinal fever." Further inquiry by the food inspector 

 into these cases showed that the victims had not eaten oysters at all. 

 Such reports as these, containing not the least foundation of truth, 

 undoubtedly inflict an undeserved hardship upon an industry of 

 much importance, and every precaution should be taken to substan- 

 tiate such statements before they are made public. 



PRESENCE OF BACILLUS COLI AND BACILLUS TYPHOSUS IN OYSTERS. 



The present investigations disclose no reason, biological, anatom- 

 ical, or otherwise, why oysters and other shellfish can not become 

 contaminated when exposed to sewage-polluted waters, and the 

 following references upheld the conclusion that this occurs. 



Klein 38 reports: "Bacillus coli (typical) was found in 5 out of 8 

 cockles." Houston 33 concludes his report on the bacteriological 

 examination of deep-sea oysters by saying: "The results show that 

 in deep-sea oysters derived from deep-sea water, remote from sewage 

 pollution, B. coli and coZi-like microbes and also the spores of B. 

 enteritidis sporogenes are either absent or, at all events, seldom 

 detectable. The same is true of surface water over such oysters." 



Smith 62 found B. coli, B. enteritidis sporogenes, and streptococci in 

 fluid from shellfish grown on grounds suspected to be polluted, but 

 failed to find these germs from areas free from sewage. 



Hewlett 30 says: "From my observations I have no hesitation, 

 therefore, in concluding that oysters from water uncontaminated with 

 sewage do not normally contain the colon or allied bacilli or the 

 Bacillus enteritidis sporogenes." He examined 32 oysters from dif- 

 ferent sources, and, with the exception of 2, not one of them con- 

 tained B. coli or B. enteritidis sporogenes. 



In making an examination of Charles River clams, Dr. Hill 32 says : 



These clams contain within their intestines at least three species of bacteria char- 

 acteristic of sewage. These organisms were not found in the intestines of clams or 

 oysters from less contaminated or uncontaminated waters. The general proposition 

 is accepted, therefore, that food which may be eaten raw should never be exposed 

 to untreated sewage containing the typhoid bacillus nor to uninfected sewage unless 

 the food is of such a character that it can be thoroughly cleansed before it is eaten. 



Beale 2 in his work on clams says : 



The results of this examination proved that the clams were grossly polluted with 

 sewage, inasmuch as the B. coli communis could be detected in ^fa and the B. enteri- 

 tidis sporogenes in -^ part of the clam. It is especially noteworthy that even after 

 boiling 15 minutes the Bacillus communis could be recovered from the bodies of the 

 clams. 



Ewart 19 concludes that mussels can be obtained free from all evi- 

 dence of sewage pollution, and states further 



That the number of Bacillus coli found in the mussels corresponds closely to the 

 environment, hence the mussel can not be regarded as a filter accumulating harmful 

 organisms. * * * 



