ABSTRACT
Although toxicity is an inherent property of a substance, the nature and extent of the toxic manifestations in an organism that is exposed to the substance depend on a variety of factors. The obvious ones are the dose and duration of exposure. However, they also include such less obvious host factors as the species and strain of the animal, gender and age, nutritional and hormonal status as well as the
presence of disease such as hypertension or compromised function as in AIDS. Various environmental (physical and social) factors also play a part. In addition, the toxic effect of a chemical may be influenced by simultaneous, concurrent, or prior exposure to other chemicals.
