Release of acids and alcohols was negligible with EFs below. The emission of S- and N-containing compounds were below for all experiments. 23 with a new class “terpenes” including p-cymene (C 10H 14), monoterpenes (C 10H 16), terpenoids (C 10H 14O, C 10H 16O) and sesquiterpenes (C 15H 24). Compounds measured with the PTR-ToF-MS were categorized as described in Klein et al. Identification and quantification of gaseous emissions from condiment useįigure 1 shows the chemical composition and emission factors (EF) for pan-frying lean beef in canola oil with varying amounts of grained black pepper and “Herbs de Provence” (from now on called “herbs” including rosemary 20%, savory 26%, oregano 26%, thyme 19% and basil 3%). In this study we (i) identify and quantify terpene emissions from cooking processes, (ii) estimate their SOA production potential and (iii) evaluate their impact on indoor air quality. Real-time characterization of aerosol and gas phase composition of frying meat with different amounts of herbs and/or pepper was performed using state of the art on-line mass spectrometeric techniques, including a proton transfer reaction time-of-flight mass spectrometer (PTR-ToF-MS) and a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). Using two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-ToF-MS), the first measurements of the volatile and intermediate volatility compounds released upon heating pepper and common herbs were made. Most NMOG reported in previous studies are aldehydes from frying process, however the impact of NMOG emissions from other cooking processes on indoor gas and particle phase concentrations has never been assessed. In addition to PM, these processes have been shown to emit large amounts of NMOGs 20, 21, 22, 23. Cooking processes have been recognized as major contributors to particulate matter (PM) concentrations in indoor 11, 12, 13, 14 and outdoor 15, 16, 17, 18, 19 environments. Both secondary organic aerosol (SOA) and aged NMOGs from terpenes may have deleterious effects on human health 7, 10, demonstrating the importance of identifying indoor terpene sources. These compounds are thought to originate primarily from detergent use 4, 5, 6, 7 and are now believed to be the main source of indoor secondary organic aerosols, upon reaction 8, 9. In addition to high indoor levels of directly emitted primary organic aerosols, deleterious non methane organic gases (NMOG, e.g. The main sources of primary particles indoors in developing countries are biomass burning emissions 2 while in developed countries cooking emissions are thought to be the main contributor 3. Comparatively, the characterization of indoor air pollution has received less attention, although we spend up to ninety percent of our time indoors, where the air can be orders of magnitudes more polluted. In response to this, substantial scientific effort has been devoted to the real-time determination of the chemical composition and the sources of the urban organic aerosols, which are believed to be a major cause of these premature deaths. More than three million people die prematurely each year from outdoor air pollution, more than malaria and HIV combined, and without action the number of deaths will double by 2050 1. In summary we demonstrate that cooking with condiments can constitute an important yet overlooked source of terpenes in indoor air. These compounds are highly reactive in the atmosphere and lead to significant amounts of secondary organic aerosol upon aging. The average total terpene emission rate from the use of herbs and pepper during cooking is estimated to be 46 ± 5 gg -1 Herbs min -1. The emissions of frying meat with herbs and pepper include large amounts of mono-, sesqui- and diterpenes as well as various terpenoids and p-cymene. Further, the secondary organic aerosol production potential of the gas-phase emissions was determined by smog chamber aging experiments. Here the effect of herbs and pepper on cooking emissions was investigated for the first time to the best of our knowledge using state of the art mass spectrometric analysis of particle and gas-phase composition. Nevertheless, cooking emissions remain poorly characterized. Cooking is widely recognized as an important source of indoor and outdoor particle and volatile organic compound emissions with potential deleterious effects on human health.
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