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The polycyclic hydrocarbons are members of a broad class of chemicals produced by incomplete combustion of organic matter. Cigarette smoke, vehicle exhaust, forest fires, and even charcoal-broiled meat have been shown to contain substantial quantities of these potent carcinogens.

The polycyclic hydrocarbons are members of a broad class of chemicals produced by incomplete combustion of organic matter. Cigarette smoke, vehicle exhaust, forest fires, and even charcoal-broiled meat have been shown to contain substantial quantities of these potent carcinogens.

Smoking And Cancer

== Smoking And Cancer ==

 

In the early part of the sixteenth century, explorers returning from the New World brought tobacco to Spain and England. The introduction of tobacco was in response to man’s search for contentment; indeed pipe smoking, tobacco chewing, and the use of snuff were reputed to have medicinal action. But, since the earliest times, smoking has also been condemned as a foul-smelling, loathsome custom, harmful to health. The centuries-long controversies became particularly intense after 1930, when the produc- tion and use of tobacco, especially of cigarettes, reached enormous proportions and in- creasing deaths from lung cancer were becoming evident.

In the early part of the sixteenth century, explorers returning from the New World brought tobacco to Spain and England. The introduction of tobacco was in response to man’s search for contentment; indeed pipe smoking, tobacco chewing, and the use of snuff were reputed to have medicinal action. But, since the earliest times, smoking has also been condemned as a foul-smelling, loathsome custom, harmful to health. The centuries-long controversies became particularly intense after 1930, when the produc- tion and use of tobacco, especially of cigarettes, reached enormous proportions and in- creasing deaths from lung cancer were becoming evident.