The skin notation in the MAC list and classification of dangerous chemicals.

The European Union has published a list of dangerous chemicals, along with classification and labeling; in 1997 the list was adapted to the requirements of Polish regulations and has been continuously updated since then. We have decided to adopt data on dangerous chemicals classification in the list referring to their dermal absorption to assess whether the skin notation is required in the maximum admissible concentration (MAC) list. In Poland, the Group of Experts for Chemical Agents (GECA) decides on assigning the skin absorption notation (symbol Sk) when analyzing the literature data collected in order to prepare occupational exposure limits documentation. The LD50s value serves as the main criterion for assigning the notation. The limit value of 1000 mg/kg has been set as the criterion for applying the skin notation. Documented results of animal and human research, which point to systemic effects resulting from dermal exposure and physicochemical characteristics enabling calculation of the dermal absorption rate may also be used as the basis for assigning the skin notation. Chemicals for which GECA recommended using the skin notation in the 2004 MAC list have been analyzed. It was concluded that information on the classification of chemicals in the list of dangerous chemicals is useful for assessing the skin absorption, but quantitative assessment of absorption rate compared to "safe" levels, using the available theoretical models, should also be attempted.