Polluted Water Can Kill You 231 



source of many unnecessary infections unless strict attention is di- 

 rected to cleanliness, both of the individual bathers and of the pool 

 itself. Chlorination under controlled supervision is an important 

 step in maintaining sanitary conditions for the swimmers, and a 

 residual concentration of at least six-tenths of a part of chlorine 

 per million parts of water should be maintained. Eye irritation 

 may be caused by stronger chlorine residuals. 



Persons suffering from open skin infections should not be 

 permitted to swim in these pools, and special medicinal foot baths 

 between the pool and the locker rooms can help to minimize such 

 skin diseases as "athlete's foot." 



ICE AS A POTENTIAL AGENCY IN DISEASE DISSEMINATION 



Until a relatively few years ago ice could be harvested from 

 any pond, pool, lake, or reservoir, and it could be sold on the 

 market irrespective of the quality of the water before it was 

 frozen. 



Before the widespread use of refrigerators many a city-bred 

 child looked forward to the arrival in the neighborhood of the ice 

 man so he could "appropriate" a sliver of ice when the man was 

 busy making a delivery. In looking back upon that era, public 

 health authorities might well wonder if any cases of typhoid fever 

 might have originated from the eating of "infected" ice. 



This so-called natural ice is customarily harvested during the 

 latter part of winter and is stored in ice-houses until the summer 

 demand moves the cakes from storage. Authorities differ as to the 

 relative danger involved in eating ice made from polluted water. 

 The one group points out that as ice forms on the surface of open 

 bodies of water, the crystals tend to come down in a pure state and 

 impurities are excluded. It is interesting to note that these same 

 persons frequently summarize their opinions by stating that, if 

 possible, ice should not be harvested from bodies of water known 

 to be polluted. Jordan remarked that ice from highly polluted 

 water could not be expected to contain many, if any, disease-pro- 

 ducing organisms after three or four months of storage. After 

 six months of storage ice can be considered to be safe, and this 



