Ammonia.

Also known as Anhydrous Ammonia, Ammonium Hydroxide or Ammonia-D. One of the most widely produced chemicals in the United States. It is used in the manufacturing of dyes, explosives, fabrics, plastics, pesticides and can be found in many household cleaning solutions. Ammonia in most forms, is both caustic and hazardous to humans

Ammonia has powerful antiseptic and antimicrobial qualities but it also has highly toxic effects on human lungs and mucus membranes. Occupational studies in humans show that regular exposure to ammonia increases the risk of asthma, shortness of breath and reduced pulmonary (lung) function.

Studies in animals show that mild exposure(1 hour per week) to low concentrations irritate the upper respiratory tract. Increased exposure(3 hours per 2 weeks) to high concentrations result in severe damage to the upper and lower respiratory tract and alveolar capillaries(lungs). Prolonged or repeated exposure shows increased signs of lesions and carcinomas of the nasal membranes. No human testing has been done for increased exposure.