The Decomposition of Daminozide (Alar) to Form Unsymmetrical Dimethylhydrazine (UDMH) in Heated, pH Adjusted, Canned Solutions

Abstract

Processing conditions were chosen to determine the influence of temperature, pH, and processing on model solutions containing daminozide residues. Daminozide (succinamic acid 2, 2-dimethylhydrazide) fortified solutions (12.5 ppm) containing 50mM NaH2PO4 and 24% sucrose (w/w) were adjusted to pH 3.0, 3.6, or 4.0 and either heated (100°C) for 0, 5, 10, or 15 min in sealed cans and cooled or heated (80°C) for 0, 5, or 10 min in open cans, sealed, heated (100°C) for 5 min, and cooled. Daminozide degradation due to heating was less than the HPLC detection limit (1.5 ppm) for all of the treatments. Unsymmetrical dimethylhydrazine (UDMH) concentration was significantly affected by heating time, pH, and processing. Heating of daminozide solutions in sealed cans produced approximately 1 ppm of UDMH for every minute of heating at 100°C. Heating of daminozide solutions in open cans at 80°C resulted in simultaneous production of UDMH in the solution and loss of UDMH through volatilization. Maximum degradation of daminozide was observed at pH 3.6.