Cutaneous Toxicity of Gasoline as an Environmental Pollutant on Mice Skin: Histological and Ultrastrucural Studies

The present investigation was undertaken to determine whether gasoline with different octane number (90 and 80) exposure in healthy Swiss albino mice might affect the skin, in order to declare more recognition on the adverse changes that might occur as a result of exposure to this pollutant. Sixty Swiss albino mice were used and divided into 3 subgroups : control-subgroup, topically treated -subgroup with gasoline 90 and topically treated -subgroup with gasoline 80, both groups two and three treated with (0.5ml/kg B.W.) for 8 weeks.Determination of benzene concentration and some heavy metals in both types of gasoline (90 and 80), determination of some heavy metals bioaccumulation in skin after exposure to both types of gasoline (90 and 80),light and electron microscopical studies were performed.It was found that gasoline 80 contained more concentrations of benzene, lead , cadmium and nickel than gasoline 90. The accumulation of lead, cadmium and nickel in the skin have the following order lead > cadmium > nickel. The light microscopical examinations showed dermatitis such as epidermal hyperplasia, micro abscesses, hyperkeratosis and destruction of the dermis depending upon treatment duration from 4 to 8 weeks. After 8 weeks of topically treated mice with both gasoline type , the scanning electron microscope examination showed scales covering the mice skin and the transition electron microscope showed cytoplasmic vacuoles and mitochondrial degeneration in keratinocytes of all epidermal layers of the mice skin . Moreover, the spinosum keratinocytes of mice skin topically treated with gasoline 80 for 8 weeks had pyknotic nuclei,in addition to expansion of intercellular spaces in the stratum corneum.