Inhalation Exposure to PM-Bound Polycyclic Aromatic Hydrocarbons Released from Barbecue Grills Powered by Gas, Lump Charcoal, and Charcoal Briquettes.

The present study seeks to define the possible cancer risk arising from the inhalation exposure to particle (PM)-bound polycyclic aromatic hydrocarbons (PAHs) present in barbecue emission gases and to compare the risk depending on the type of fuel used for grill powering. Three types of fuel were compared: liquid propane gas, lump charcoal, and charcoal briquettes. PM2.5 and PM2.5-100 were collected during grilling. Subsequently, 16 PAHs congeners were extracted from the PM samples and measured quantitatively using gas chromatography. The content of PM-bound PAHs was used to calculate PAHs deposition in the respiratory tract using the multiple path particle dosimetry model. Finally, a probabilistic risk model was developed to assess the incremental lifetime cancer risk (ILCR) faced by people exposed to PAHs. We found a distinctly greater PAHs formation in case of grills powered by charcoal briquettes. The summary concentration of PAHs (Σ16PAH) ranged from <0.002 μg/m3 (gas grill) to 21.52 μg/m3 (grill powered by briquettes). Daily exposure of a grill operator, while grilling meat, to PM2.5 -bound PAHs, adjusted to benzo[a]pyrene toxicity equivalent (BaPeq ), was 326.9, 401.6, and 0.04 ng/d for lump charcoal, charcoal briquettes, and gas powered grill, respectively. Exposure to PAHs emitted from charcoal briquettes was four orders of magnitude greater than that for gas grill. The ILCR followed a log-normal distribution, with a geometric mean of 8.38 × 10-5 for exposure to PM2.5 -bound PAHs emitted from gas grills unloaded with food and as high as 8.68 × 10-1 for the grills loaded with food over charcoal briquettes. The estimated cancer risk for people who would inhale barbecue particles for 5 h a day, 40 days a year exceeds the acceptable level set by the U.S. Environmental Protection Agency. We conclude that the type of heat source used for grilling influences the PM-bound PAHs formation. The greatest concentration of PAHs is generated when grilling over charcoal briquettes. Loading grills with food generates conspicuously more PAHs emissions. Traditional grilling poses cancer risk much above the acceptable limit, as opposed to much less risk involving gas powered grills.