1. All substances are toxic at some dosage. All are non-target at some
dosage. Only the dosage makes a substance an effective poison.
a. Dosage levels and organisms, population and community response.
b. Effect of duration of exposure, chronicity.
c. Acute toxicity of herbicides is moderate to low; exposure is
extremely low and brief in the field. Worker health precautions.
2. Herbicides in comparison to other pesticides.
a. Persistence - medium to short.
b. Physical properties leading to accumulation lacking in herbicides.
c. Lower in acute toxicity than most insecticides.
