Skin Absorption as a Route of Exposure for Aflatoxin and Trichothecenes

Abstract

Airborne occurrence of mycotoxins in agricultural and residential environments has generated concern that these toxins may be absorbed via the skin and respiratory tract. This paper summarizes information available on the in vivo and in vitro cutaneous permeability of several mycotoxins (aflatoxin, T-2 toxin [T-2], diacetoxyscirpenol, and verrucarin A).

Published data is used to calculate the dose absorbed during cutaneous exposure to fungal toxins in hypothetical agricultural and research laboratory environments. These estimated doses of T-2 (0.004 and 0.041 μg/kg, respectively) were 25,000 and 2,439 times less than a reported oral dose (100 μg T-2/kg/day) which caused immunosuppression in monkeys.

In general, exposure of human skin to aflatoxin and trichothecenes results in slow absorption. The risk of systemic toxicity resulting from dermal exposure increases in the presence of high toxin concentrations, occlusion, and vehicles which enhance penetration.