is pure tobacco cancerous Health Risks of Smoking Health Effects of Cigarettes: Cancer
Description
Depending on how much you smoke, the stains can start to look brownish

There is also a noticeable amount of oil on each, and while there are a few protruding veins, none of them are large enough to be overly distracting

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Even if it's not exactly zero, the consequences of taking tobacco out of people's lungs and bodies will be huge for cardiovascular disease as well as lung and other cancers," he said