Effect of tert-Butylhydroquinone(TBHQ) on the Formation of Nitrosamines in the Reaction of Secondary Amines with Nitrite.

Abstract

tert-Butylhydroquinone (TBHQ), an antioxidant for edible fats and oil, inhibited nitrosamine formation in the reaction of secondary amines with nitrite under acidic conditions. The inhibitory effect may be due to the loss of nitrite available for nitrosation. TBHQ was oxidized with nitrite into 2-tert-butyl-p-benzoquinone (TBQ), which was active in enhancing nitrosamine formation in the presence of an adequate amount of available nitrite. TBQ readily reacted with secondary amines to form 1 : 1 secondary amine-TBQ adducts whose structures were established to be 2-tert-butyl-5 (and 6)-amino-p-benzoquinones. The adducts may be nitrosated to be transformed into the nitrosamines, or they may catalytically enhance the nitrosamine formation.