NMOR is a component of tobacco products. As of 2014, detectable levels of NMOR are present in tobacco products in the United States and China. The presence of NMOR and other n-nitrosoamines is not limited to cigarettes, but is found in smokeless tobacco products (snuff tobacco, Snus, etc.) as well. Volatile nitrosamines, including NMOR, are detectable in the urine of tobacco smokers.