OELs 6 - Final report V3 - Poly aromatic hydrocarbons (PAH)

The Carcinogens, Mutagens and Reprotoxic substances Directive (Directive 2004/37/EC), here-inafter the CMRD, protects workers from exposure to carcinogens, mutagens or reprotoxic substances at work. The aim of this study is to support the European Commission’s Impact Assess-ment (IA) of a potential Occupational Exposure Limit (OEL) and Biological Limit Value (BLV) for Polycyclic Aromatic Hydrocarbons (PAH). The Exposure Risk Relationship (ERR) uses benzo[a]pyrene (BaP) (inhalable fraction) as indicator substance to characterise exposure to the PAH mixture, it is a very potent (non-threshold) carcinogen and a large amount of exposure data is available for this substance. No single metabolite/ biomarker can adequately represent the variability of PAH exposure mixtures and the 2022 RAC opinion considers that BaP is the most appropriate available marker. The OEL policy options are based on BaP. However, RAC did not propose a limit value due to BaP being a non-threshold carcinogen. RAC further proposes to establish a BLV with 3-hydroxybenzo[a]pyrene (3-OHBaP, the metabolite of BaP) in urine as the marker substance, based on a correlation equation between air concentration and metabolite in urine.