Environmental aldehydes exposure and the health implications among a cohort of traffic police in Lebanon

Aldehydes may be associated with the pathogenesis of several diseases. This study is aimed at evaluating the potential effects of traffic-related aldehyde exposure on oxidative stress and inflammatory biomarkers among occupationally exposed workers. We have undertaken a biomonitoring of 99 traffic officers in Beirut and its suburbs through personal air monitoring assessed by diffusive samplers and through the use of biomarkers of oxidative stress and inflammation. Personal formaldehyde, acetaldehyde, acrolein, benzaldehyde, butanal, and hexanal exposure, in addition to urinary and plasma malondialdehyde (MDA) in both pre and post-exposure, were assessed by HPLC-UV. Pre and post-exposure lung function were tested by spirometry. Post-exposure inflammatory markers including erythrocyte sedimentation rate (ESR), white blood count (WBC), C-Reactive Protein (CRP), and urea were determined. Our results show that the mean individual exposure levels of traffic officers to aldehydes ranged between 9.54 and 331 µg/m³. Formaldehyde and acrolein exceeded the occupational exposure limit. Aldehydes levels were higher than those measured in many cities in Italy, Spain, Morocco, and others. Oxidative stress and inflammation biomarkers were significantly higher after 5 days of exposure to aldehydes. Plasma and urinary MDA levels in traffic police officers on pre-shift day 1 could be distinguished from post-shift on day 5. Significant predictors of post-exposure plasma MDA concentration were working years and formaldehyde, and those for post-exposure urinary MDA were formaldehyde, benzaldehyde, and butanal. ESR and WBC were negatively associated with post-exposure plasma MDA. Our results suggest that exposure to traffic-related aldehydes may lead to increased oxidative stress and inflammation in traffic officers.