Local effects on the body include conjunctivitis, dermatitis, sore throat, and congestion. Ingestion produces effects ranging from mild irritation to vomiting. Inhalation can cause increased respiration followed by depression and convulsions. For most laboratory animals, rotenone is much more toxic intravenously than orally. The particle size of the powder determines the inhalation toxicity.
Fine powders are much more toxic than coarse particles.
Dogs fed low to moderate doses of rotenone for 28 days experienced vomiting and excessive salivation, but no negative weight gain. Dogs fed rotenone for six months at low doses had reduced food consumption and therefore reduced weight gain. At necropsy, the most frequent lesions were bleeding patches in the small intestine. Some of the mothers died due to rotenone poisoning also. While low doses of the pesticide were sufficient to cause adverse effects in the pregnant rats, there is not enough information to draw any connection to the potential for reproductive risks to humans.