Smoking is the major cause of mortality with bronchogenic carcinoma of the lungs and is one of the factors causing death due to malignancies of the larynx, oral cavity, oesophagus, bladder, kidney, pancreas, stomach and uterine cervix and coronary heart diseases. Nicotine is the major substance present in the smoke that causes physical dependence. The additives do produce damage to the body for example, ammonia can result in a 100-fold increase in the ability of nicotine to enter into the smoke. Levulinic acid, added to cigarettes to mask the harsh taste of the nicotine, can increase the binding of nicotine to brain receptors, which increases the ‘kick’ of nicotine.
Smoke from the burning end of a cigarette contains over 4000 chemicals and 40 carcinogens. It has long been known that tobacco smoke is carcinogenic or cancer-causing. The lungs of smokers collect an annual deposit of 1 to 1 Vi pounds of the gooey black material, Invisible gas phase of cigarette smoke contains nitrogen, oxygen and toxic gases like carbon monoxide, formaldehyde, acrolein, hydrogen cyanide and nitrogen oxides. These gases are poisonous and in many cases interfere with the body’s ability to transport oxygen.
i. What is the major cause of mortality with bronchogenic carcinoma of the lungs?
ii. What is the main substance in cigarette smoke that causes physical dependence?
iii. How does levulinic acid affect the action of nicotine?
iv. What harmful gases are found in the invisible gas phase of cigarette smoke?