Skin Absorption: A Potential Contributing Factor to the BEI

Abstract

In the process of establishing a Biological Exposure Index (BEI), all significant routes of exposure to the chemical are considered, so that the expected quantity of the biological marker present in the specimen can be realistically estimated. Thus, BEIs are the measure of the amount of chemical absorbed into the body. The BEI is considered to be a bioequivalent to an atmospheric Threshold Limit Value (TLV). If the contribution to total body burden by dermal absorption is substantial, difficulties arise when the value of the BEI is to be reconciled with the value expected to be present due to inhalation exposure only at the TLV concentration. This apparent discrepancy becomes large with chemicals which readily penetrate the skin barrier and exhibit quick systemic absorption. The purpose of this paper is to focus attention on the contributory role of dermal absorption by reviewing pertinent data from the literature. These data readily illustrate why such discrepancies can occur. Industrial hygiene and medical personnel should be alerted by any inconsistency between atmospheric monitoring and BEI values and investigate the reasons for each occurrence. In the majority of cases, bad work habits, individual personal hygiene practices, or adequacy of dermal protection and decontamination methods are highly suspect. Thomas, A.A.: Skin absorption: a potential contributing factor to the BEI.