4,4' Methylenebis(2 chloroaniline)

4,4'-Methylenebis(2-chloroaniline) (MOCA, MBOCA, bisamine) is a substance used as a curing agent in polyurethane production. It is a proven human carcinogen standing on the WHO List of IARC Group 1 carcinogens, with a current threshold limit value of 0.01 ppm in the industrial atmosphere. Animal studies have resulted in tumor growth in the liver, lung, and bladder. Employee exposure is often monitored by measurement of urinary MOCA in free and/or conjugated form.

It is a weak base with a slight odor and is reactive to active metals such as sodium, potassium, magnesium and zinc.