We know how hard it is to quit smoking. But the fact remains that the inhaled irritants and super-heated air from smoking cause irritation and swelling of the larynx and vocal folds and put you at risk for developing vocal fold cancer. Smoking causes other voice problems as well, such as Reinke's edema. There is no safe amount to smoke. Even if you just smoke a little, you are at risk for voice problems and serious disease.
Hoarseness can be an early sign of vocal fold cancer. Smokers who are hoarse for more than a week or two need to have their vocal folds checked, whether or not they consider the voice quality a problem. An evaluation at the Grabscheid Voice and Swallowing Center can address this, or see your local otolaryngologist (ear, nose & throat doctor). The most important thing is not to delay a visit to the doctor. Identifying cancer early is very much a matter of life or death.