Is skin exposure to water mainly occupational or nonoccupational? A population-based study

Skin exposure to water is considered to contribute to hand eczema. Knowledge about total water exposure during a day is scanty.

To investigate self-reported water exposure at work as well as throughout the day.

Skin exposure to water was assessed from two questionnaire-based health surveys: the nationwide Environmental Health Survey 2007 (EHS), which enquired about water exposure throughout the day, and the Stockholm Public Health Survey 2006 (PHS), which probed water exposure at work. Answers from 19,667 individuals (EHS) and 18,318 individuals (PHS) were available for analysis.

In total, 22% of respondents (women 30%, men 12%) reported skin exposure to water more than 20 times during an entire day (EHS) compared with 6% (women 8%, men 4%) at work (PHS). In a univariate analysis, using a merged file comprising data from the EHS and the PHS, water exposure more than 20 times a day was more common in the EHS (prevalence proportion ratio 3·570, 95% confidence interval 3·353-3·802). In multivariate models the variables studied did not fulfil the criteria for being confounders. Water exposure at work declined with increasing age in both women and men (P < 0·0001) as did water exposure during the entire day in men (P < 0·0001). However, women were equally exposed during the entire day across age groups (P = 0·205).

High water exposure over the entire day was found to be considerably more frequent than exposure at work. Thus, a significant proportion of water exposure seems to occur outside work. This should be considered in prevention of hand eczema and when counselling patients with hand eczema in clinical practice.