Assessment of dermal exposure to chemicals

The methods for the dermal exposure assessment vary in their complexity and are in some sense complementary to each other. The most easy-to-use methods involve a pseudo-skin-approach, such as gloves and removal by washing. In some cases generic modelling appears to be possible. The experimental methods can indicate and even quantitate the presence of chemicals on the skin. This enables studies on the occurrence of local effects in relation to the exposure. When the interest is on systemic effects, the dermal exposure is only of interest if it represents the amount that is available for penetration through the skin. This may vary largely between compounds due to the large variation in dermal absorption. When this degree of absorption is not known, the alternate method may be biological monitoring, at least when it is based on a detailed pharmacokinetic knowledge of that compound. The most sophisticated method, applied to study occupational exposures, is formed by a combination of monitoring on clothing (pseudo-skin), hand washing (removal) and biological monitoring. In any case, the assessment of dermal exposure should be based on a sampling strategy that takes into account the distribution of the contamination on the body, the variation in time of the exposure, the duration of the exposure as well as the degree of skin protection afforded by clothing.