[New aspects for the evaluation of health effects caused by exposure against halogenated hydrocarbons at the working place. A literature review (author's transl)].

Halogenated hydrocarbons with over 150 toxicological relevant substances represent a considerable group among the numerous noxes at the working-places. Tri- and perchloroethylene are industrially widely used solvents for cleaning, degreasing and extraction. At the workplace the main amount of intake occurs via lung. Hepato-, nephro-, neuro- and cardiotoxicological effects are important solvent-induced health impairments. If the valid maximum concentrations in the work area (MAK-value) for the specific substance is not exceeded, altogether health hazards are impropable. With information of the "Unfallverhütungsbericht" only 23 cases of intoxications at the workplace were indemnified in 1977 for the first time. The causes for this low number are: installation of closed equipments, automation of the procedures and improvement of the personal hygiene. However praxis in occupational medicine shows, that there is a great number of persons in small firms that has contact with these solvents. For the surveillance and judgement of these solvent-exposed persons exist two methods. First the airborne concentration of the chemical compound can be determined at the working area. Second the solvent and/or its metabolites can be quantitative analyzed in the biological material. This method, called "biological Monitoring (BM)" has important advantages. BM should be prefered in cases of non-continuous, short-term exposures to concentrations of high degree. The judgement has to be done in relation to biological permissible limits (Biologische Arbeitsstoff-Toleranz-Werte, BAT, biological threshold limit values, BTLV's). Based on our longtime experience this specific and sensitive method should be used with priority.