Electronic cigarettes should not be assumed to be a safe alternative to smoking tobacco because of the lack of carcinogens and tar in e-cigarette liquid, dermatologists have been advised.

A literature review for effects of e-cigarette use on the skin or mucosa has found evidence that they may also be harmful to human skin.

The report published in the Journal of the American Academy of Dermatology shows that e-cigarettes have been associated with four areas of dermatologic manifestations.

• Contact dermatitis

A number of cases of contact dermatitis have been reported secondary to the release of nickel from the heating coil of e-cigarette devices. This typically causes irritation and pruritic rash to the dominant hand used to hold the e-cigarette, the report notes.

• Thermal injury

More than 2000 cases of thermal cutaneous injuries were reported in the US in a two year period, the report notes. Burn injuries are typically caused by thermal runaway reaction of the e-cigarette lithium battery source.

• Oral lesions

Switching from traditional cigarettes to e-cigarettes does not reduce the risk of oral mucosal lesions and may increase it, literature reports suggest. In particular,  there have been reports of increased incidence of nicotine stomatitis, hyperplastic candidiasis, oral lichen planus and black hairy tongue (lingua villosa nigra).

• Cytological effects

Exposure to e-cigarette smoke has been shown to reduce cell viability, change ultrastructure, and induce the release of proinflammatory cytokines (interleukin 6 [IL-6], IL-8, and IL-10) in human keratinocytes. Adverse effects of neutrophil function by e-cigarettes have been speculated to play a negative role in psoriasis and other systemic conditions.

“The association between e-cigarettes and the multiple skin-related conditions outlined in this review suggest that e-cigarettes are not safe alternatives to traditional tobacco cigarettes in terms of development of dermatologic issues,” the authors of the review conclude.

“As the use of e-cigarettes continues long-term and the number of users rises, additional studies should investigate the dermatologic manifestations of e-cigarette consumption,” they advise.