ABSTRACT
We often say to measure exposure, measure the concentration in a medium next to the appropriate body surface. For inhalation and ingestion, this is relatively straightforward. But dermal absorption involves the skin, the body’s largest and most extended organ. How is one to determine the appropriate body surface in many situations? For example, in showering some portions of the body are receiving occasional “hits” from small droplets of water, other portions of the body may be constantly exposed as the water rivulets cascade downward, still other parts (e.g., the hair and skull) may be completely dry and unexposed. This chapter deals with how various exposure assessors have dealt with the problem of measuring dermal absorption. Although some efforts have been ingenious, we will see that the problem remains unsolved.
