Common ingredients of vehicles such as perfumes, antibacterial agents, emulsifiers and other surface active agents, propylene glycol, lanolin and wool alcohols were tested in eczema patients over a three-year period. Perfume allergy was detected in 3.6% of the cases, sensitivity to thiomersal in 2%, to sorbic acid in 0.8%, to parabens in only 0.3%, and to wool alcohols in 1.2%. Reactions to emulsifiers were seen over 1% of those tested.