Dermal exposure and changes in skin barrier function of base metal refinery workers co-exposed to cobalt and nickel

Abstract

Refi nery workers are exposed to many metals, including cobalt and nickel, both of which are skin sensitisers, causing allergic contact dermatitis. Dermal exposure, and changes in skin barrier function [skin hydration, transepidermal water loss (TEWL) and skin surface pH] from start to end of shift, of base metal refi nery workers co-exposed to cobalt and nickel, were assessed. Changes in SH were inconsistent, while TEWL generally increased and SS-pH decreased. The decrease in SS-pH is most likely due to direct skin contact with sulphuric acid. Dermal exposure was variable even though workers wore personal protective gloves, highlighting the limitations of personal protective clothing in controlling exposure. None of the workers presented with allergic contact dermatitis (ACD). The small sample size of this study limits the interpretation of the absence of ACD, but the healthy worker effect and ethnic differences in skin structure and function may be contributing factors.