Staining

Limited data concluded, with minimal evidence that smokeless tobacco, produced more staining than nicotine pouches, and both deemed to cause far less staining in comparison to traditional cigarette smoke.²⁸ Studies concluded that e-liquid flavors and dyes could stain hard tissue, if used as a dual source with ONPs. Concentrations of the nicotine and exposure time are also factors that affect the distribution and severity of staining. More studies are still needed to support or refute this relationship.²⁸