The frequency of SCES was significantly increased in the alcoholics analyzed (10.6 &/- SD 0.66) when compared to the frequency of a control group (8.4 &/- SD 0.51). Statistical analysis of the data obtained showed that the increase was not apparently related to age, sex, cigarette smoking, duration in years of alcohol abuse, nutritional status or type of alcoholic beverage commonly consumed by the individual. Alcoholics recovering for at least one year from alcohol abuse were examined and the frequency of SCES was found to be equal to the SCE frequency in the control group. There was no statistical significance between the age, sex of the individual, smoking history and years of abstention from alcohol abuse with respect to the frequency of SCES. Therefore, one year of abstention appears sufficient to allow the SCE frequency to return to that found in the control group. In order to keep extraneous factors at a minimum and to analyze the effect of a particular factor, such as alcohol, on the number of SCES, a careful medical history and screening program was followed. However, more information is needed to determine which factors play a role in causing genetic damage and inducing SCES and to determine the significance SCES may have with respect to genetic information and function.