- Project number: F 2379
- Institution: Federal Institute for Occupational Safety and Health (BAuA)
- Status: Completed Project
Description:
Trichlorethylene (TRI) is a hazardous liquid used in industrial processes, primarily as a solvent. On account of its carcinogenic effects, the use of TRI has required authorisation since 2016 under Annex XIV of the REACH Regulation. Some of the authorisations that have been issued stipulate the deployment of closed technical systems. Yet, even in these cases, TRI’s high volatility means it is fundamentally possible for employees to be exposed, as a result of leaks for example, or when filling, emptying, and maintaining such systems.
Against this background, the intention was to use biomonitoring to investigate employees’ exposure to TRI in work environments where it is used in closed systems. The investigations were conducted at laboratories that carry out testing for the asphalt industry, which used TRI as an extraction agent for bitumen in special automatic extraction machines as provided for by Authorisation REACH/18/9/4. The biomonitoring involved the measurement of TRI in exhaled air and the TRI metabolite trichloroacetic acid in employees’ urine. Both system operators who worked with TRI themselves and bystanders (colleagues who did not work with TRI) were examined.
It was ascertained that all the participants from the six asphalt laboratories had occupationally induced levels of TRI in their bodies. In a few cases, bystanders even had higher levels of TRI than some TRI system operators. Overall, however, all the TRI levels found, measured as the concentration of trichloroacetic acid in urine, were well below the current equivalence value for the acceptable concentration according to Technical Rule for Hazardous Substances (TRGS) 910, which corresponds to a risk of developing cancer of 4:10,000. At four of the six laboratories, however, the levels of TRI found in the system operators were high enough to be associated with an additional risk of developing cancer greater than 4:100,000.
The results of the measurements show that, despite the deployment of closed systems, working with TRI can result in employees, including bystanders, being subjected to OSH-relevant levels of exposure. The measurement data consequently support the substitution of TRI for which the European Commission is striving. Furthermore, there is a need to improve the coverage of bystanders’ exposure in risk assessments.