SOURCES OF CONTAMINATION. ‘oo 
with which the oystermen have to contend. Regulations should be 
enforced requiring better care of the hands and more personal clean- 
liness in general on the part of oyster shuckers. To this end, the 
necessary toilet facilities should be provided for their welfare and 
comfort. 
Bacteriological tests made by exposing freshly prepared agar plates 
4 inches in diameter where oysters were being shucked show the rela- 
tive bacterial content of the air in such places. One set of such 
experiments gave the following figures: 
A one-minute exposure resulted in the growth of 130 colonies; 
two minutes, 180 colonies; three minutes, 220; four minutes, 350; 
and five minutes, 430 colonies. The organisms consisted of molds, 
yeasts, spore-bearing and various chromogenic and other colonies. 
Fig. 13.—Clam diggers’ huts, where shucking is done. Sanitary conditions on the interior generally very 
unsatisfactory. 
Is it strange that under such conditions the oystermen have difficulty 
in keeping opened oysters, especially when tubs and containers are 
not covered? Contrast these results with a similar set of plates 
exposed in the bottling room of a clean dairy where sanitary condi- 
tions obtained: One-minute exposure, 9 colonies; two minutes, 15 
colonies; three minutes, 20; four minutes, 24; and five minutes, 30 . 
colonies. | :, 
WASHING OYSTERS. 
It is essential that both the water and ice used in washing and 
cooling shucked oysters should be free from pollution. Natural ice 
harvested from polluted sources should not be used for this purpose, 
and even artificial ice may become contaminated by careless handling. 
A number of samples of water used for washing oysters were exam- 
