Percutaneous absorption of aromatic amines and the risk assessment resulting from the dermal pathway

Abstract

Aromatic amines (AA) are compounds of different carcinogenic potency causing occupational bladder cancer. The percutaneous absorption of AA is mostly appraised to be high. Many AA are, therefore, assigned with skin notations. However, for the assessment of the dermal exposure route only little data are available. Additionally, in many studies the skin penetration data for AA are provided as absorbed percentage of applied dose or permeability coefficients, which are less useful in risk assessment. In this overview, the toxicological relevance of percutaneous absorption of AA was evaluated and a percutaneous penetration ranking for some AA is proposed. A continuous skin exposure of hands to AA for a few minutes can exceed the inhalative exposure over 8 hours at occupational threshold limit values in the workplace air. The health risk resulting from the percutaneous absorption of AA can be considerable. Also the dermal exposure to azo dyes, which can be metabolized to AA, should be considered with caution.