Morpholine oleate is used in glazing wax which covers fruit. NMOR can be generated by the nitration of morpholine, causing its presence in waxed fruits.Health Canada, the Canadian governmental department of public health, has stated in 2002 that this does not pose a risk to human health.
Consumption of nitrate-rich diets is correlated with levels of salivary and urinary NMOR. The presence of NMOR can also be observed in gastric juices.