The influence of hydrochloric acid and chlorine exposure on the skin barrier function of precious metal refinery workers

Abstract

Various hazardous chemical substances are used daily in the platinum refineries. This study was conducted in order to determine whether platinum refinery workers’ exposure to HCl and Cl2, two of the hazardous chemical substances, could damage the skin barrier function (i.e. skin hydration, trans–epidermal water loss and skin surface pH) of these workers. The participants of this study were fourteen workers that were exposed to HCl and Cl2, constituting the exposed group, and a control group that was made up of ten workers located in another building detached from the plant. Due to the fact that some of the workers in the exposed group used barrier creams, the exposed group was further divided into two groups, namely the barrier cream (BC) and non–barrier cream (nBC) groups. Workers’ skin barrier function was measured on six distinct anatomical skin areas, including indirectly exposed skin (i.e. palm, wrist and back of the hand that was covered with protective gloves) and directly exposed skin (i.e. neck, cheek and forehead). These skin measurements were conducted before, during and at the end of shifts, while airborne personal and area HCl and Cl2 exposure were concurrently assessed. The results of this study indicated that indirectly exposed skin of the exposed group was dehydrated, and only Cl2 exposure contributed to a disrupted skin barrier function on the back of the hand. Due to limited correlations with skin hydration, it remained unclear whether HCl and Cl2 exposure had an influence on skin hydration. The palm of the exposed group had abnormally high TEWL levels, but only HCl contributed to the palm’s damaged skin barrier function. Skin surface pH for indirectly and directly exposed skin was found to be within the normal range, but both HCl and Cl2 exposure contributed towards a decrease in skin surface pH for the directly exposed skin of the exposed group. It also remained unclear whether barrier creams enhanced the exposed group’s skin barrier. This lack of certainty can most likely be ascribed to the small participant group. Additional factors such as the use of latex gloves, continuous washing and scrubbing of hands, and contact with contaminated personal protective equipment and workplace surfaces could also have contributed to an impaired skin barrier. Workers in the platinum refinery industry are potentially exposed to chlorinated platinum salts, and an impaired skin barrier may result in skin permeation thereof, which could lead to sensitisation and allergy. It is, however, recommended that washing facilities need to be improved; personal hygiene procedures and skin aftercare need to be emphasised during training sessions; and neoprene gloves need to be used to reduce the allergy risk of latex gloves.