Using human biomonitoring for the risk assessment of polycyclic aromatic hydrocarbons in occupational exposures

Abstracts publicado em: Toxicology Letters. 2019;314S1:S76.Background and Purpose: The Human Biomonitoring Initiative (HBM4EU) is a joint effort of 28 countries, the European Environment Agency and the European Commission, co-funded under Horizon 2020. HBM4EU is generating evidence of the current exposure of European citizens to chemicals and the possible health effects in order to assess the associated risks and support policy making towards human health protection. Polycyclic aromatic hydrocarbons (PAH) were considered one of the 1st priority substance groups to be addressed. In the scope of this project, the present work aimed to evaluate the added value of human biomonitoring (HBM) for the PAH risk assessment process, in the case of occupational exposure. Methods: An extensive literature search was performed to identify scientific papers published between 2008 and 2018 that included air monitoring and HBM data in several occupational settings based in Europe. Among them, those papers presenting urinary 1-hydroxypyrene (1-OHP) quantification - the most common exposure biomarker of pyrene and a surrogate for exposure to PAHs mixtures - were selected. Based on the 1-OHP values the excess lifetime cancer risk (ELCR) for workers, concerning lung cancer, was estimated following the ECHA recent approach (https://echa.europa.eu/fi/applying-for-authorisation/evaluating-applications). ELCR values calculated using air and HBM data were compared. Results: Based on the criteria described, only 7 out of 28 papers were considered for ELCR estimation. Overall, high ELCR values were estimated (several values higher than 10-4). Moreover, for some studies (3 out of 7) the ELCR estimation using HBM data yielded values higher than those estimated from air monitoring data. This might indicate that, for those specific workplaces, transdermal absorption or even hand-mouth exposure can have an important role in the total exposure to PAH and that the HBM data allows a more accurate PAH exposure assessment. Nevertheless, these findings should be interpreted with caution, since ELCR estimates from air monitoring data are based on Benzo[a]pyrene (BaP) concentrations while HBM-based ELCR determination uses urinary 1-OHP concentration that reflects exposure not only to BaP but to all PAHs, irrespectively of sources or routes of exposure. This work claims attention for two main aspects, namely: i) the exposure levels are still high in some occupational settings and ii) there is a need for developing new occupational studies, applying a set of exposure biomarkers or a more specific biomarker for BaP exposure, which would allow a better ELCR estimation for exposed workers.The HBM4EU project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 733032.