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BACTERIAL TOXINS

Anyone who has ever suffered the agony of vomiting, nausea, cramping and diarrhea after eating improperly handled or contaminated food knows that bacteria can produce toxins. Simple staphylococcal food poisoning ("ptomaine poisoning") usually leaves it victims afraid they will die in its initial phases, then, as the disease progresses, afraid that they won't die. Like other enterotoxins, staphylococcal toxin remains even after the organism dies. The symptoms it produces are the body trying to rid itself of the toxin. Proper handling of food is the simplest way to prevent it. But there are more fearful bacterial toxins -- one of them is the reason mothers instruct their children never to buy dented or bulging canned good.

Of all the earth's natural poisons few are as deadly as botulin toxin, the chemical secretion of Clostridium botulinum. Botulism takes its name from the Latin word for sausage because it was first identified in 1793 when thirteen people in a small German town fell sick after eating the same sausage. The bacterium was isolated a hundred years later when band members in a small Belgian town fell sick after eating a ham. Shaped like a stout rod, Clostridium boutlinum commonly and harmlessly grows in the oxygen free layers of the soil. When environmental conditions do not favor continued growth it produces nearly indestructible spores that can lie dormant for years.

The organism can be found everywhere and spores constantly contaminate food of all types. If the food is not cooked properly before canning, to kill the spores, they survive inside the can or bottle. In the oxygen free environment provided there the spores germinate and the bacteria rapidly multiply, secreting their lethal toxin. Whoever eats the food becomes dizzy, tired, and develops severe headaches. Vision grows blurry. The toxin damages the autonomic nervous system by blocking the transmission of nerve impulses. Eventually death occurs by asphyxiation when the respiratory muscles submit to paralysis.

Commercial canning processes rarely allow the survival of C. botulinum spores. The last outbreak traced to a commercial packer in the United States occurred in 1925. The handful of cases that still occur are associated with either home canned products (where a vacuum is not created) or products not heated properly in which a partial vacuum exists (such as sausage). Bulging cans are the sign of anaerobic bacteria gas-producing activity and in the early years of this century it was common practice for some unscrupulous store owners to dent cans in this condition. The hitting of the can rediffused the gas. Mothers warned their children not to purchase dented cans, a piece of folk wisdom that continues to this day.