Patch testing with mixes. Note on mercaptobenzothiazole mix.

Mixes for patch testing conserve space and time. History and current usage of mixes are reviewed with comments on stability, concentration, consistency, use of infrequent allergens, vehicles and ingredients of mixes. Phenomena of 'aging', 'maturity', 'balance' 'stability' and 'quenching' have been studied elsewhere for naturally occurring mixes such as aroma chemicals (fragrances and flavorings). Little is known about any such changes for mixes of chemicals made for patch test purposes. The correct concentration of mercaptobenzothiazole (MBT) for MBT mix is discussed.