In a preliminary study to examine possible lymphocyte chromosomal damage, we have tested two cytogenetic endpoints, namely, chromosomal aberrations (CA) and sister chromatid exchange frequencies (SCE), in 24 mobile phone users (12 nonsmoker-nonalcoholic subjects and 12 smoker-alcoholics), who used digital mobile phones for at least 2 years, employing Gaussian Minimum Shift Keying modulations with uplink frequencies at 935-960 MHz. and downlinks at 890-915 MHz. For comparison, the control study group included another 24 individuals, matched according to their age, sex, drinking and smoking habits, as well as similar health status, working habits, and professional careers; but did not use mobile phones. Blood samples of 12 mobile users (6 smoker-alcoholic and 6 nonsmoker-nonalcoholic) and 12 controls (identical to mobile users in every respect) were further treated with a known mutagen Mitomycin-C (MMC) to find out comutagenic/synergistic effect. A complete blood picture for each individual was assessed with an automatic particle cell counter.

There was a significant increase (P < 0.05) in dicentric chromosomes among mobile users who were smoker-alcoholic as compared to nonsmoker-nonalcoholic; the same held true for controls of both types. After MMC treatment, there was a significant increase in dicentrics (P < 0.05) and ring chromosomes (P < 0.001) in both smoker-alcoholic and nonsmoker-nonalcoholic mobile users when compared with the controls. Although SCEs showed a significant increase among mobile users, no change in cell cycle progression was noted. The hematological picture showed only minor variations between mobile users and controls.