238 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Effect of Cigarette smoke on skin Dryness i i Active Smokers Passive Smokers Non Smokers Figure 2. Skin dryness measured via analysis of corneocytes on D-Squames. Effect of Cigarette Smoke on skin wrinkling 90 8O 7O 60 5O 40 30 20 I Active Passive Smokers Smokers Non Smokers Figure 3. Skin wrinkling via image analysis of silicon replicas of the periorbital area. PART II Efj•ct of chronological age and sun exposure on barrier functions of skin. As observed in Figures 4a and 4b, sub-division of non-smokers by age indicates a reduction in TEWL with increasing age possibly due to dehydration of skin. It is clear from these data that age, unlike smoke exposure, played no significant role in skin damage. The degree of sun exposure appeared to exhibit a good dose response with the increase in TEWL. Active smokers who received severe sun exposure exhibited a significantly worse skin barrier (p = 0.025) than non-exposed non-smokers who received the same UV exposure. Observation of the barrier functions of this population revealed that although some cigarette smoke-exposed individuals avoided the sun, their barrier function was still significantly more impaired than that of non-exposed non-smokers (p = 0.02) exposed to a similar amount of sun exposure. Efj•ct of chronological age and sun exposure on skin dryness. There was some correlation between smoke exposure, age, and skin dryness and also between smoke exposure, sun

EFFECT OF CIGARETTE SMOKE ON SKIN 239 2O 18 16 • 14 I-- 12 10 Effect of Cigarette Smoke and age on barrier functions Active Smokers Passive Smokers Effect of Cigarette smoke and sun exposure on barrier functions Active Passive smokers Smokers Non Non Smokers Smokers [] age 35-45 [] age 46-55 • age 56 [] Slight sun I• Moderate [] Severe Figure 4. a: Effect of chronological age and cigarette smoke on barrier functions. b: Effect of sun exposure and smoke skin barrier functions measured via transepidermal water loss. exposure, and skin dryness (Figure 5). The panelists with slight sun exposure did not exhibit as much skin dryness as those having medium or severe UV exposure. Excessively sun-exposed smokers had 76% drier skin as compared to non-smokers with low sun exposure. As observed in Figure 5b, the skin of non-exposed non-smokers who received minimal sun exposure was was not as dry as that of smokers having the same sun exposure (p = 0.078). Passive smokers exhibited a significantly more arid (p = 0.026) skin than non-smokers. Efj•ct of chronological age and sun exposure on skin wrinkling. More wrinkles were observed in non-smokers over 56 years of age, but below 55 years of age there was no significant dose response. Sun exposure appeared to exhibit a good dose response with the intensity of wrinkling. As observed in Figure 6b, non-exposed non-smoking individuals exposed to mild-to-slight sun exhibited a significantly lower (p 0.001) skin wrinkling than active smokers having the same sun exposure. DISCUSSION Stratum corneum, composed of skin surface lipids, is responsible for the epidermal water 7.5 o_ m 6 • 5.5 : 4.5 '• 4 3.5 3 Effect of Cigarette Smoke and age on Skin Dryness I I Active Passive Non Smokers Smokers Smokers Effect of Cigarette Smoke and []age 35-45 sun exposure on skin dryness m•age 46-55 I m age 56 [] Slight sun •a Moderate ml[] SevI , i i Active Passive Non Smokers Smokers Smokers Figure 5. a: Effect of chronological age and cigarette smoke on skin dryness. b: Effect of sun exposure and smoke on drying of skin.