Utilization of Scrap Tires Versus Firewood and Liquefied Petroleum Gas as Fuels for Singeing Meat in Ghana: Chemical Emissions via Smoke

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Utilization of scrap automobile tires for singeing food animal carcasses at meat processing facilities in Ghana (and other countries) has been ongoing for over 50 yr. This practice can release chemical pollutants such as carbon monoxide (CO), benzene, sulfur dioxide (SO2), particulate matter (PM), etc. into the air via smoke. Exposure to these chemicals has been associated with adverse health effects such as respiratory impairment, mutagenesis, and cancer. This study aimed at determining the levels of CO, benzene, SO2, PM2.5, and PM10 emitted via smoke produced at three slaughter slabs (using tires and/or firewood) and Kumasi Abattoir (which uses liquefied petroleum gas [LPG]) for meat singeing. A Chip Measurement System and an Aerosol Monitor were used to quantify the chemical levels in real time. Results indicate that the average levels of both PM2.5 and PM10 from LPG-based smoke (0.7±0.2 mg/m3; 95% CI, 0.3-1.0 and 0.7±0.2 mg/m3; 95% CI, 0.3-1.1, respectively) were significantly lower than that of firewood (24.2±5.2 mg/m3; 95% CI, 13.1-35.3 and 24.2±5.2 mg/m3; 95% CI, 13.1-35.3, respectively) and tire-derived smoke (83.60±6.67 mg/m3; 95% CI, 69.9-97.3) and 86.7±6.4 mg/m3; 95% CI, 73.5-99.9, respectively). Mean CO levels via smoke from tire-derived (143.3±3.1 ppm; 95% CI, 137.1-149.6) and firewood (138.7±8.0 ppm; 95% CI, 121.4-155.9) were significantly higher than that of LPG-based smoke (5.2±0.2 ppm; 95% CI, 4.7-5.7). Average SO2 level from LPG-based smoke (1.61±0.7 ppm; 95% CI, 0.1-3.1) was significantly lower than that of tire-derived smoke (8.9 ± 0.3 ppm; 95% CI, 8.3-9.7). No significant difference in SO2 levels was detected between LPG- and firewood-based smoke. Mean benzene level emitted via scrap tire-derived smoke (5.7±0.6 ppm; 95% CI, 4.4-7.0) was significantly higher compared to those of firewood- (1.1±0.6 ppm; 95% CI, -0.2-2.4) and LPG-based smoke (0.2 ± 0.0 ppm; 95% CI, 0.2-0.2). Results demonstrate that tire burning for meat singeing generates chemical pollutants at levels significantly higher compared to those of LPG. These data suggest that slaughter slab operators and residents nearby these meat processing facilities may be at high risk for adverse health effects linked to these pollutants. A more comprehensive study is warranted to sufficiently characterize this tire burning-health effect link.


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