Tobacco smoke is phototoxic.

BACKGROUND

Both cigarette smoke and ultraviolet (UV) radiation are known to cause changes of the skin which can be regarded as premature ageing.

OBJECTIVE

To assess the theory that the effects of these two exposures could be linked by a phototoxic action of cigarette smoke.

METHODS

A photohaemolysis test was used, in which human erythrocytes were incubated with cigarette smoke condensate, followed by UV irradiation and measurement of exposure-dependent haemolysis.

RESULTS

Cigarette smoke condensate was clearly phototoxic. Photohaemolysis depended on the concentration of the condensate and UV dose and was more pronounced after exposure to UVA-rich than UVB-rich radiation.

CONCLUSIONS

Phototoxicity may be a mechanism by which cigarette smoking causes premature skin ageing. An enhancing effect on photocarcinogenesis has also to be considered.