Chemical speciation, including polycyclic aromatic hydrocarbons (PAHs), and toxicity of particles emitted from meat cooking operations.

We assessed the chemical properties and oxidative stress of particulate matter (PM) emissions from underfired charbroiled meat operations with and without the use of aftertreatment control technologies. Cooking emissions concentrations showed a strong dependence on the control technology utilized, with all emission rates showing decreases with the control technologies compared to the baseline testing. The organic acids profile was dominated by the saturated nonanoic, myristic, palmitic, and stearic acids, and the unsaturated oleic, elaidic, and palmitoleic acids. Cholesterol was also found in relatively high concentrations. Lower and medium-weight polycyclic aromatic hydrocarbons (PAHs) were the dominant species for all cooking experiments. Heavier PAHs were also detected in high concentrations, especially in the particle-phase. For the nitrated PAH emissions (nitro-PAHs), low molecular weight compounds dominated the cooking emissions. Under the present experimental conditions, the heterocyclic aromatic amines (HAAs) showed very low concentrations, which suggests these species are rarely formed in meat cooking PM. The most efficient control technology for reducing the majority of the toxic pollutants was the electrostatic precipitator, which resulted in total emissions reductions on the order of 95%, 79%, 90%, 96%, 90%, and 94%, respectively, for particle-phase PAHs, gas-phase PAHs, particle-phase nitro-PAHs, gas-phase nitro-PAHs, particle-phase HAAs, and gas-phase HAAs compared to the baseline testing. Our experiment showed that cooking aerosol contained higher levels of prooxidants in the particle-phase and the corresponding vapors contained higher levels of electrophiles. Overall, the use of control technologies reduced the redox and electrophilic activities of cooking PM.

Particulate matter emissions and gaseous air toxic pollutants from commercial meat cooking operations.

This study assessed the effectiveness of three novel control technologies for particulate matter (PM) and volatile organic compound (VOC) removal from commercial meat cooking operations. All experiments were conducted using standardized procedures at University of California, Riverside's commercial test cooking facility. PM mass emissions collected using South Coast Air Quality Management District (SCAQMD) Method 5.1, as well as a dilution tunnel-based PM method showed statistically significantly reductions for each control technology when compared to baseline testing (i.e., without a catalyst). Overall, particle number emissions decreased with the use of control technologies, with the exception of control technology 2 (CT2), which is a grease removal technology based on boundary layer momentum transfer (BLMT) theory. Particle size distributions were unimodal with CT2 resulting in higher particle number populations at lower particle diameters. Organic carbon was the dominant PM component (>99%) for all experiments. Formaldehyde and acetaldehyde were the most abundant carbonyl compounds and showed reductions with the application of the control technologies. Some reductions in mono-aromatic VOCs were also observed with CT2 and the electrostatic precipitator (ESP) CT3 compared to the baseline testing.

Impact of biodiesel on regulated and unregulated emissions, and redox and proinflammatory properties of PM emitted from heavy-duty vehicles.

The emissions and the potential health effects of particulate matter (PM) were assessed from two heavy-duty trucks with and without emission control aftertreatment systems when operating on CARB ultra-low sulfur diesel (ULSD) and three different biodiesel blends. The CARB ULSD was blended with soy-based biodiesel, animal fat biodiesel, and waste cooking oil biodiesel at 50vol%. Testing was conducted over the EPA Urban Dynamometer Driving Schedule (UDDS) in triplicate for both trucks. The aftertreatment controls effectively decreased PM mass and number emissions, as well as the polycyclic aromatic hydrocarbons (PAHs) compared to the uncontrolled truck. Emissions of nitrogen oxides (NOx) exhibited increases with the biodiesel blends, showing some feedstock dependency for the controlled truck. The oxidative potential of the emitted PM, measured by means of the dithiothreitol (DTT) assay, showed reductions with the use of biodiesel blends relative to CARB ULSD for the uncontrolled truck. Overall, the cellular responses to the particles from each fuel were reflective of the chemical content, i.e., particles from CARB ULSD were the most reactive and exhibited the highest cellular responses.

Detailed Analysis of Criteria and Particle Emissions from a Very Large Crude Carrier Using a Novel ECA Fuel.

Ocean going vessels (OGVs) operating within emission control areas (ECA) are required to use fuels with ≤0.1 wt % sulfur. Up to now only distillate fuels could meet the sulfur limits. Recently refiners created a novel low-sulfur heavy-fuel oil (LSHFO) meeting the sulfur limits so questions were posed whether nitric oxide (NOx) and particulate matter (PM) emissions were the same for the two fuels. This project characterized criteria pollutants and undertook a detailed analysis of PM emissions from a very large crude oil carrier (VLCC) using a distillate ECA fuel (MGO) and novel LSHFO. Results showed emission factors of NOx were ∼5% higher with MGO than LSHFO. PM2.5 emission factors were ∼3 times higher with LSHFO than MGO, while both were below values reported by Lloyds, U.S. EPA and CARB. A detailed analysis of PM revealed it was >90% organic carbon (OC) for both fuels. Elemental carbon (EC) and soot measured with an AVL microsoot sensor (MSS) reflected black carbon. PM size distributions showed unimodal peaks for both MGO (20-30 nm) and LSHFO (30-50 nm). Particle number (PN) emissions were 28% and 17% higher with the PPS-M compared to the SMPS for LSHFO and MGO, respectively.

Emissions from commercial-grade charbroiling meat operations induce oxidative stress and inflammatory responses in human bronchial epithelial cells.

Commercial charbroiling emissions are a significant source of ambient particulate matter (PM) in urban settings. The objective of this study was to determine whether organic extract of PM emissions from commercial charbroiling meat operations could induce an inflammatory response in human bronchial epithelial cells and whether this effect was mediated by oxidative stress. PM samples were collected during cooking hamburgers on a commercial-grade under-fired charbroiler and sequentially extracted with water and methanol to obtain the aqueous PM suspension (AqPM) and organic extract (OE). The pro-oxidative and pro-inflammatory effects of OE were assessed using human bronchial epithelial cell line BEAS-2B. While AqPM did not have any effect, OE effectively induced the expression of heme oxygennase-1 and cyclooxygenase-2 in BEAS-2B cells. OE also up-regulated the levels of IL-6, IL-8, and prostaglandin E2. OE-induced cellular inflammatory response could be effectively suppressed by the antioxidant N-acetyl cysteine, nuclear factor (erythroid-derived 2)-like 2 activator sulforaphane and p38 MAPK inhibitor SB203580. In conclusion, organic chemicals emitted from commercial charbroiling meat operations could induce an inflammatory response in human bronchial epithelial cells, which was mediated by oxidative stress and p38 MAPK.