Identification of work-related exposure to carcinogenic substances in Germany

Occupational exposures to carcinogenic substances like benzo[a]pyrene, ethylenoxide, trichlorethene or butadiene occur in variety fields of industry. The risk strategy for carcinogenic substances in Germany entails a system for assessing hazards due to exposure at the workplace. Substance-specific concentration values were determined to which a certain risk of contracting work-related cancer as a result of exposure on a day-to-day basis at work is assigned. Below an acceptance concentration, exposure is deemed acceptable; above a tolerance concentration, it is no longer deemed tolerable. Ranges of low, medium and high risk can thus be distinguished and subsequently linked to measures for minimization of the exposure which are not specific to a particular substance. The data is recorded in the measurement system for exposure asssessment – MGU and is documented in the MEGA exposure database. By comparing the sub-stance-specific acceptance or tolerance concentrations with data from MEGA it is possible to identify workplaces at which employees are exposed to a higher than the accepted risk of contracting occupationally induced cancer. Evaluations show that over 50% of the values measured in each case for ethylene oxide and trichlorethene are above the respective acceptance concentration. In many cases, the tolerance concentration is exceeded by the 75th or even the 50th percentiles of sectoral groups or groups of working areas. For example, for benzo[a]pyrene, 662 measured values lie above the analytical limit of detection, 246 of these in the medium-risk range, 414 in the high-risk range. Only 132 measured values can be clearly assigned to low-risk exposure. In contrast, for 1,3-butadiene all measured values with just one exception lie below the analytical limit of detection.