Résumé
This study evaluates the health risks associated with exposure to atmospheric emissions from energy recovery of cashew nut shells through pyrolysis and combustion processes. The analysis focuses on two risk categories: carcinogenic risks, assessed by the Individual Risk Excess (ERI), and noncarcinogenic risks, estimated by the Hazard Quotient (HQ). Samples were collected at the source (industrial chimney) using isokinetic sampling on activated carbon tubes and subsequently analyzed by gas chromatography coupled with mass spectrometry to identify and quantify Volatile Organic Compounds (VOCs). These concentrations were then modelled at 500 meters using an atmospheric dispersion model of the Screening Modelling in Air Quality Assessment type. The results show that benzene and 1,3-butadiene are the primary contributors to carcinogenic risks, with a total ERI exceeding the acceptable threshold of 10⁵. For benzene, direct combustion poses approximately 1.7 times the risk compared to pyrolysis. Similarly, 1,3-butadiene shows a risk reduction with pyrolysis (about 1.3 times lower). Overall, pyrolysis reduces the total carcinogenic risk by 26.9% when compared to direct combustion. Regarding non-carcinogenic risks, the Hazard Quotients (HQ) for toluene (4.38×10−5 for combustion and 4.03×10−5 for pyrolysis) and styrene (5.8×10-4 for combustion and 1.9×10-4 for pyrolysis) remain below 1, indicating limited short-term health effects. Comparing the two recovery processes, the overall hazard quotients show a slight reduction of 11.1% between direct combustion and pyrolysis of cashew nut shells. The study recommends technological improvements and strict regulatory measures to sustainably manage emissions sustainably, thereby protecting public health and the environment.