Safe disposal of carcinogenic nitrosamines

A simple one-step procedure for chemically degrading nitrosamine residues generated in the research laboratory is described. Treatment with aluminum-nickel alloy powder and aqueous alkali rapidly reduced all 11 nitrosamines studied to the corresponding amines. Hydrazines were produced as transitory intermediates, but these potential carcinogens were also easily reduced under the conditions employed, and no products except amines, ammonia, and, in some cases, alcohols were detected in the final reaction mixtures. Reduction proceeded smoothly in every other solvent system tested, except that reactions in acetone or dichloromethane solution were sometimes slow, incomplete, and/or led to unidentified products; therefore, we cannot recommend the procedure for use in these solvents. Otherwise, the method was efficient, reliable, and inexpensive and has been recommended as one of the preferred means of degrading potentially carcinogenic nitrosamines to innocuous products. Details of its application to some decontamination and disposal problems commonly encountered in the research laboratory are provided. Data illustrating this procedure's advantages over six other reducing systems are also presented.