downtoearth-subscribe

Cancerous threat

researchers in the us say that people exposed to second-hand smoke during their daily lives have shown to absorb a chemical that is strongly suspected to cause lung cancer. Stephen Hecht of the University of Minnesota Cancer Center in Minneapolis told last week's meeting of the American Chemical Society in Las Vegas that people exposed to second-hand smoke absorb a substance called 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, or nnk. nnk is found only in tobacco smoke and is created by burning nicotine. In animal studies it causes adenocarcinoma, a kind of lung cancer common in passive smokers, Hecht says.

He studied nine non-smokers who worked in the smoking section of a residential hospital for Canadian military veterans. He collected their urine and found a metabolite of nnk called nnal -Gluc. Levels were about one-seventh of those in smokers. But samples from people who were not known to be exposed to smoke showed no trace of nnal -Gluc. Hecht had already found the metabolite in the urine of non-smokers exposed to smoke in the laboratory. His new study confirms that the same thing happens in the real world to passive smokers.

Related Content