Evidence of increased skin irritation after wet work: impact of water exposure and occlusion.

Background: Exposure to humid environments/water and prolonged glove occlusion are both believed to cause irritant contact dermatitis.

Objectives: To study the effects of different forms of wet work, especially the differences between water exposure and occlusion, by using an experimental model simulating occupational wet work.

Methods: The responses to water exposure and occlusion over multiple daily exposure periods for 7 days were compared in 73 volunteers. After the 1 week exposure, the sites were irritated with sodium lauryl sulfate (SLS). Comparison was performed via visual inspection and bioengineering methods.

Results: Whereas occlusion did not induce measurable alterations in skin physiology, water exposure for more than 3 hr daily caused a significant increase in transepidermal water loss (TEWL) as compared with the control areas. SLS irritation of the previously occluded and the water-exposed sites induced higher TEWL and clinical scores in a time-dependent fashion as compared with the control areas, with more pronounced reactions in the water-exposed sites than in the occluded sites.

Conclusion: Both previous occlusion and water exposure were capable of inducing higher susceptibility to SLS irritation. Skin hydration by occlusion had a different biological effect than water exposure. Short occlusions seem to harm the skin less than water exposure for the same duration.