This study focuses on finding if the hazards produced by gasoline 90 (vehicle fuel in Egypt) are less than those produced by gasoline 80 in healthy Swiss albino mice. Sixty mice were equally divided into 3 groups: group one (control), group two (topically treated with 0.5ml gasoline 90 /kg B.W.) and group three (topically treated with 0.5ml gasoline 80 /kg B.W.). The specimens were taken after 4 and 8 weeks. Determination of bioaccumulation of some heavy metals, biochemical examination and a light microscopical study were performed. It was found that the accumulation of lead, cadmium and nickel in the liver had the following order lead > cadmium > nickel. After topically treated with gasoline 90 and 80 for 8 weeks, there was an increase in the activities of the serum liver function enzymes (alkaline phosphatase, alanine aminotransferase and aspartate amino transferase) and adenosine deaminase and a decrease in the total protein content of the liver homogenate. There were pathological changes which were more pronounced by treatment with gasoline 80 than with gasoline 90 depending upon treatment duration from 4 to 8 weeks. After 4 weeks of topically treating mice with gasoline 90, cellular infiltration, dilatation of blood sinusoid and cytoplasmic vaculation were demonstrated. After 8 weeks the liver architecture of the mice was disrupted with liquid infiltration and the presence of foamy areas. After 4 weeks of topically treating mice with gasoline 80, we observed a shrinking of the blood sinusoid, hypatocyte vaculation with pyknotic nuclei and different stages of karyolysis. After 8 weeks, there was a noticeable hypatocyte degeneration and complete disappearance of blood sinusoids in the liver sections of the mice.