Topical effects of molten salt on rat integument: a histological and photometric assessment

The topical effects of the molten salt 1-methyl-3-ethylimidazolium tetrachloroaluminate (melt) and its organic component, the organic salt 1-methyl-3-ethylimidazolium chloride were tested on rat integument. Evaluation was accomplished using standard histological techniques supplemented with digital analysis using the microscope photometer. Two groups of animals were treated with 1.5 ml of either the melt or the organic salt for 10 consecutive days. A third group treated with the melt had the treated area flushed with running water 5 min after each application (wash). Significant treatment effects were observed in rats treated with the melt and wash preparations while the effects of the organic salt were unremarkable. The melt induced an ulcerative dermatitis with acanthosis while the wash produced only mild acanthosis and dermatitis. This damage appears to result from the penetration of aluminum chloride in the melt through the skin and its toxic effects on the cells of the dermis and epidermis.