SELECTIVE TOXICITY
Selective toxicity can also be a result of a difference in bio-chemistry in the 2 types of cells. For example, bacteria do not absorb folic acid but synthesize it from p-aminobenzoic acid, glu- tamic acid, and pteridine, whereas mammals cannot synthesize folic acid but have to absorb it from the diet.
Selective toxicity means that a chemical produces injury to 1 kind of living matter without harming another form of life even though the 2 may exist in intimate contact.
- They may be related to each other as parasite and host or may be 2 tissues in 1 organism.
- This biological diversity interferes with the ability of ecotoxicologists to predict the toxic effects of a chemical in 1 species (humans) from experiments performed in another species (laboratory animals).
- The living matter that is injured is termed the uneconomic form (undesirable), and the matter protected is called the economic form (desirable).
INDIVIDUAL DIFFERENCE IS RESPONSE
Even within a species, large interindividual differences in response to a chemical can occur because of subtle genetic differences.