Usually, six different levels are used, starting with fifty percent of the LD 50 . Daily observations are made and growth is monitored. Autopsies are also generally done on the test animals. These studies are normally done over 12 to 24 weeks. Rats are used for oral toxicity because they have a similar digestive system and similar metabolic responses as humans.
Dermal toxicity is studied to determine the potential to cause skin irritation.
Tests are done on rabbits' skin, abraded skin, and eyes. For the abraded skin tests, the rabbit's skin is rubbed with sandpaper until just before it bleeds and then the chemical is applied. Inhalation tests are also performed. It is questionable whether any of these tests are really useful to determine the effects of these chemicals on humans. Testing determines toxicity as well as how much of the product is needed to control the pest targeted and what the exposure to humans would be if for example this amount was applied on someone's lawn.