GPT and animal viral hepatitis: This definitely rules out infective conditions such as viral hepatitis (as AST and/or ALT ought to have increased correspondingly) [51] but certainly not toxic hepatitis, which according to Davis [53], is possible as a result of enzyme induction in the face of certain environmental agents such as aromatic hydrocarbons (and these are superabundantly present in petroleum products), some food additives and some pesticides, which according to Conney [54] have enzyme-inducing properties.