Contact allergy to petrolatums. (III). Allergenicity prediction and pharmacopoeial requirements.

Several pharmacopoeias set limits on the polycyclic aromatic hydrocarbon content in petrolatum. UV absorbance measurement of aromatic extracts of petrolatum samples has been shown to be a more reliable method than direct UV absorbance measurement as prescribed by several pharmacopoeias for the determination of that content, but the presence of allergenic polycyclic aromatic hydrocarbons does not always correlate with lower UV absorbance. Biological tests are ultimately the only certain method of detecting biologically active compounds. Polycyclic aromatic hydrocarbons can also be irritant and carcinogenic. Therefore, universally uniform and very stringent limits should be set restricting their presence in pharmaceutical grade petrolatum.