Ultra-weak chemiluminescence of smokers' blood.

An extremely sensitive single photon counter was developed that could quantitatively detect very weak, spontaneous light emission from human blood samples. Ultra-weak chemiluminescence intensities of cigarette smokers' blood plasma reached significantly higher levels than those of nonsmokers. Elevated levels of the chemiluminescence of the smokers' plasma returned to the nonsmokers' range within 12 hr after cessation of cigarette smoking. We propose that this higher chemiluminescent property of the smokers' plasma might be somehow related to cigarette smoking-associated health disorders, e.g., carcinogenesis.