The route of exposure, dose, and exposure length all influence the severity of health effects.
Acute burning of the eyes, nose, throat and respiratory tract caused by high levels of ammonia in the air can result in blindness, lung damage, or death.
Ammonia is a colorless, flammable gas with a terrible odor.
Urea:
Endogenous urea is usually harmless and excreted in the urine; but, if it enters the alimentary canal, it can cause poisoning.
Because urea is routinely used as a protein supplement for domestic ruminants, it is critical to have a full grasp of urea toxicity.
Urea is the major nitrogen-containing substance in mammalian urine and plays a significant role in the metabolism of nitrogen-containing substances by animals.
Urea is less dangerous than ammonia in terms of toxicity.