PTOMAINE POISONS 109 



odor, appearance, taste, and character. If the bacteria are not 

 checked in their growth, they quickly spread through the whole 

 mass of meat and make it unfit for use. Some of the decom- 

 position products of bacterial growth have a strong offensive 

 odor, and it is usually possible to detect decay by un- 

 natural odors. Meat, for example, has a slightly offensive 

 odor and an unnatural taste as soon as it is tainted with decay. 

 The decomposition of food particles which have not been 

 thoroughly washed out of cracks and crevices gives a dis- 

 agreeable odor to garbage cans, kitchen sinks, and dish 

 mops. A bad odor and an unnatural taste in foods is usually 

 a sign that bacteria are in them and that decay has begun. 



Ptomaine poisons. Every living organism, whether plant 

 or animal, throws off waste matter. The wastes of the human 

 body, for example, are perspiration, carbon dioxide, urea, and 

 the discharge from the bowels. Bacteria throw off waste matter 

 or secretions, as they are generally called, and these secretions 

 accumulate in the substances on which the bacteria live. The 

 secretions of some bacteria are harmless to man ; those of other 

 bacteria are poisonous and cause disease. Certain bacteria, 

 when growing in food, give rise to decomposition products called 

 ptomaines. Some of these ptomaines are extremely injurious 

 and cause ptomaine poisoning. Tainted meats and fish often 

 cause serious illness because of the ptomaines which they 

 contain. Bacteria develop much more rapidly and throw off 

 more secretions in warm weather than in cold weather, and 

 for this reason there are more cases of illness in summer than 

 in winter. Much sickness is caused in warm weather by 

 ice cream made from milk and cream in which poison- 

 producing bacteria have developed. Poison-producing bac- 

 teria develop rapidly in milk in warm weather, and if such 

 milk is fed to babies it brings death to them. One of the 

 most important activities of the " Baby Saving " campaigns 



