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Cooking oil fumes (COF) are known to emit a wide range of organic compounds with significant impacts on human health and urban air quality. This study used HPLC-QToF-MS and Vocus PTR-TOF to explore the chemical constituents and influencing factors of the COF generated from eight typical Chinese dishes representing different areas in a laboratory kitchen. The results revealed that both CHO and CHON compounds exhibited strong reducibility and saturability, with CHO compounds being the dominant and CHON compounds showing greater diversity. 24 among 168 CHO compounds were identical with those generated from heating soybean oil, representing 72.4%-92.3% in abundance and 22.2%-29.2% in quantity. That was 5 among 113 CHON compounds, accounting for 7.8%-10% in abundance and 4.7%-6.7% in quantity. These findings suggest that the major CHO compounds from heating soybean oil continued to dominate the abundances in dishes. The diversity of CHO compounds and the presence of CHON compounds were influenced by the food ingredients. The VOC analysis indicated that oxygen-containing organics were the major components. 6 identical VOC species between cooking dishes and heating soybean oil were identified, comprising 36.02%-67.84% of the total VOCs mass. Notably, poor ventilation could result in even higher COF concentrations in the connected room compared to the kitchen itself.
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The 2021 WHO guidelines stress the importance of measuring ultrafine particles using particle number concentration (PNC) for health assessments. However, commonly used particle metrics such as aerodynamic diameter and number concentrations do not fully capture the diverse chemical makeup of complex particles. To address this issue, our study used high-throughput mass spectrometry to analyze the properties of cooking oil fumes (COFs) in real time and evaluate their impact on BEAS-2B cell metabolism. Results showed insignificant differences in COF number size distributions between soybean oil and olive oil (peak concentrations of 5.20 × 105/cm3), as well as between corn oil and peanut oil (peak concentrations of 4.35 × 105/cm3). Despite the similar major chemical components among the four COFs, variations in metabolic damage were observed, indicating that the relatively small amount of chemical components of COFs can also influence particle behavior within the respiratory system, thereby impacting biological responses. Additionally, interactions between accompanying gaseous COFs and particles may alter their chemical composition through various mechanisms, introducing additional chemicals and modifying existing proportions. Hence, the chemical composition and gaseous components of COFs hold equal importance to the particle number concentration (PNC) when assessing their impact on human health. The absence of these considerations in the current guidelines underscores a research gap. It is imperative to acknowledge that for a more comprehensive approach to safeguarding public health, guidelines must be regularly updated to reflect new scientific findings and robust epidemiological evidence.
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Aceites , Material Particulado , Humanos , Material Particulado/análisis , Culinaria/métodos , Gases/análisis , AlimentosRESUMEN
The next-generation 650 MHz solid state power amplifier designed by the Institute of Modern Physics will utilize 24 modules with an output power of 60 kW. The outputs of each of the 12 modules will be combined using a 12-in-1 rectangular cavity combiner integrated into the rack. This cavity combiner, requiring only a single stage to combine power, is characterized by a minimal power loss and a high combining efficiency. The input couplers of the combiner are adjustable to change the number of combination channels. In the event of one amplifier module failure, the corresponding port can be adjusted to decouple, transforming the combiner to an (N-1)-channel combiner with a combining efficiency decay of 0.2%. The prototype of the combiner has been fabricated and tested with a small signal. The combining efficiency is 98.5%. In this paper, we will validate the feasibility of the combiner from the design, simulation, and experiment.
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Biodiesel, derived from alkyl esters of vegetable oils or animal fats, has gained prominence as a greener alternative to diesel due to its reduced particle mass. However, it remains debatable whether biodiesel exposure has more severe health issues than diesel. This study performed high-resolution mass spectrometry to examine the detailed particle chemical compositions and lipidomics analysis of human lung epithelial cells treated with emissions from biodiesel and diesel fuels. Results show the presence of the peak substances of CHO compounds in biodiesel combustion that contain a phthalate ester (PAEs) structure (e.g., n-amyl isoamyl phthalate and diisobutyl phthalate). PAEs have emerged as persistent organic pollutants across various environmental media and are known to possess endocrine-disrupting properties in the environment. We further observed that biodiesel prevents triglyceride storage compared to diesel and inhibits triglycerides from becoming phospholipids, particularly with increased phosphatidylglycerols (PGs) and phosphatidylethanolamines (PEs), which potentially could lead to a higher probability of cancer metastasis.
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Contaminantes Atmosféricos , Emisiones de Vehículos , Animales , Humanos , Emisiones de Vehículos/análisis , Biocombustibles/análisis , Metabolismo de los Lípidos , Gasolina/análisis , Contaminantes Atmosféricos/análisisRESUMEN
Decades of research have established the toxicity of soot particles resulting from incomplete combustion. However, the unique chemical compounds responsible for adverse health effects have remained uncertain. This study utilized mass spectrometry to analyze the chemical composition of extracted soot organics at three oxidation states, aiming to establish quantitative relationships between potentially toxic chemicals and their impact on human alveolar basal epithelial cells (A549) through metabolomics-based evaluations. Targeted analysis using MS/MS indicated that particles with a medium oxidation state contained the highest total abundance of compounds, particularly oxygen-containing polycyclic aromatic hydrocarbons (OPAHs) composed of fused benzene rings and unsaturated carbonyls, which may cause oxidative stress, characterized by the upregulation of three specific metabolites. Further investigation focused on three specific OPAH standards: 1,4-naphthoquinone, 9-fluorenone, and anthranone. Pathway analysis indicated that exposure to these compounds affected transcriptional functions, the tricarboxylic acid cycle, cell proliferation, and the oxidative stress response. Biodiesel combustion emissions had higher concentrations of PAHs, OPAHs, and nitrogen-containing PAHs (NPAHs) compared with other fuels. Quinones and 9,10-anthraquinone were identified as the dominant compounds within the OPAH category. This knowledge enhances our understanding of the compounds contributing to adverse health effects observed in epidemiological studies and highlights the role of aerosol composition in toxicity.
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Contaminantes Atmosféricos , Hidrocarburos Policíclicos Aromáticos , Compuestos Policíclicos , Humanos , Compuestos Policíclicos/análisis , Hollín/análisis , Hollín/química , Hollín/toxicidad , Espectrometría de Masas en Tándem , Hidrocarburos Policíclicos Aromáticos/toxicidad , Pulmón , Oxígeno/análisis , Metaboloma , Contaminantes Atmosféricos/análisis , Emisiones de Vehículos/análisisRESUMEN
Cooking oil fume (COF) is associated with an increased risk of health effects. The particle number size distribution (PNSD) of COF presenting as lognormal structures is recognized as a key metric in determining its exposure toxicities, but the information of its spatial distributions and impacting factors are still lacking. This study conducted real-time monitoring COF PNSD during the cooking processes in a kitchen laboratory. Results showed that COF PNSD presented as a combination of two lognormal distributions. The peak diameters of PNSD inside the kitchen were: 385 nm (very close to the source), 126 nm (5 cm above the source), 85 nm (10 cm above the source) to 36 nm (breath point, 50 cm above the source), 33 nm (sucking surface of the ventilation hood), 31 nm (1 m horizontally to the source), and 29 nm (3.5 m horizontally to the source). The reasons of this observation was the sharp decrease of temperature from the pot to the indoor environment reduced the surface partial pressure of the COF particles and caused a large amount of semi-volatile organic carbons (SVOCs) with lower saturation ratios condensed on the COF surface. With the temperature difference became insignificant with the distance further to the source, the reduction of the supersaturation helped the gasification of these SVOCs. Dispersion led to a linearly horizontal decreases ((1.85 ± 0.10) × 106#/cm3/m) in particle numbers with further distances, making the peak particle number concentrations decrease from 3.5 × 105#/cm3 at the breath point to 1.1 × 105#/cm3 at the point 3.5 m to the source. Cooking dishes also presented as mode diameters of 22-32 nm at the breath point. The amount of edible oil used in different dishes is positively correlated with the peak concentration of COF. Only increasing the exhaust force of the range hood cannot significantly change the sucked COF particle numbers and sizes, owning to that COF particles are mainly small sizes. New technologies on cleaning small size particles and efficient supplemental air should be given more considerations.
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During the global pandemic of COVID-19, the world adopted different strategies to avoid the human and economic loss, and so does China. The reduction of human activities during this time period caused reduction in PM emissions. This study adopted a HPLC-Q-TOF-MS to compare the chemical compositions of ambient aerosol samples collected in Shanghai winter before (2018, 2019) and after (2021) the COVID-19 outbreak. The identified compositions were classified into subgroups of CHO, CHN, CHON, CHONS, CHOS and CHN compounds. Results showed that CHO compounds and CHON compounds were dominating the organic compounds in ESI- and ESI+, respectively. The average percentages of CHO- compounds were 57.97 % in 2018, 58.98 % in 2019, and 43.93 % in 2021, respectively. The average percentages of CHON+ compounds were 52.74 % in 2018, 50.34 % in 2019, and 52.02 % in 2021, respectively. The proportion of aliphatic compounds increased gradually during the three years, especially in 2021, indicating that CHO compounds were less affected by aromatic precursors after the COVID-19 outbreak. The contribution of anthropogenic emissions in Shanghai was weakened compared with the previous years. In addition, there was an enhanced emission source containing hydroxyl for CHOS compound formation in 2021. The variations of atmospheric oxidation degree among the three years were not significant.
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Contaminantes Atmosféricos , COVID-19 , Humanos , COVID-19/epidemiología , China/epidemiología , Aerosoles y Gotitas Respiratorias , Compuestos Orgánicos/análisis , Estaciones del Año , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Monitoreo del AmbienteRESUMEN
Aldehyde and ketone compounds are ubiquitous in the air and prone to adverse effects on human health. Cooking emission is one of the major indoor sources. Aiming to evaluate health risks associated with inhalation exposure to aldehyde and ketone compounds, 13 carbonyl compounds (CCs) released from heating 5 edible oils, 3 seasonings, and 2 dishes were investigated in a kitchen laboratory. For the scenarios of heating five types of oil, aldehydes accounted for 61.1%-78.0% of the total emission, mainly acetaldehyde, acrolein and hexanal. Comparatively, heating oil with added seasonings released greater concentrations of aldehyde and ketone compounds. The concentration enhancement of larger molecular aldehydes was significantly greater. The emission factors of aldehyde and ketone compounds for cooking the dish of chili fried meat were much greater compared to that of tomato fried eggs. Therefore, food materials also had a great impact on the aldehyde and ketone emissions. Acetone and acetaldehyde were the most abundant CCs in the kitchen. Acrolein concentrations ranged from 235.18 to 498.71 µg/m3, which was about 100 times greater compared to the guidelines provided by Office of Environmental Health Hazard Assessment (OEHHA). The acetaldehyde inhalation for adults was 856.83-1515.55 µg and 56.23-192.79 µg from exposure to chili fried meat and tomato fried eggs, respectively. This exceeds the reference value of 90 µg/day provided by OEHHA. The findings of this study provided scientific evidences for the roles of cooking emissions on indoor air quality and human health.
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Contaminantes Atmosféricos , Contaminación del Aire Interior , Adulto , Humanos , Contaminantes Atmosféricos/análisis , Cetonas , Acroleína , Culinaria , Contaminación del Aire Interior/análisis , Aldehídos/análisis , Acetaldehído , Monitoreo del AmbienteRESUMEN
Cooking oil fume (COF) is an important source of indoor and outdoor air pollutants. COF generates a large number of organic compounds through volatilization and thermal oxidation, mainly including acids, alcohols, aldehydes and polycyclic aromatic hydrocarbons (PAHs), which can contribute 10 %-35 % to airborne organic particles in urban areas. COF not only affects human health owning to their small sizes, but also may absorb incident light due to the presence of brown carbon (BrC) chromophores in organic components. Therefore, we investigated size distributions and light absorption properties of particles produced from heating four types of edible oil. Results showed over 75 % of COF particles belonged to ultrafine particles (UFPs) and capable of absorbing light. The particle number size distributions for heating all edible oils were bimodal lognormal distribution, and the two mode diameters were within 27.9-32.2 nm and 187.7-299.6 nm. Both real-time monitoring and offline analyzing results show the average absorption coefficients of particles generated from heating soybean oil were much greater compare to those of heating other three edible oils. The mean AAE370/520 for heating soybean oil, olive oil, corn oil and peanut oil were 1.877, 1.669, 1.745 and 1.288, respectively, indicating the presence of BrC chromophores. A large proportion of BrC identified by HPLC-DAD-Q-TOF-MS only contain carbon, hydrogen and oxygen, which are CnH2nO2, CnH2n-2O2, CnH2n-4O2 and CnH2n-6O2 (9 Asunto(s)
Contaminantes Atmosféricos
, Hidrocarburos Policíclicos Aromáticos
, Humanos
, Material Particulado/análisis
, Calefacción
, Metanol
, Aceite de Soja
, Aceite de Maíz
, Aceite de Oliva
, Aceite de Cacahuete
, Contaminantes Atmosféricos/análisis
, Aerosoles/análisis
, Aceites
, Gases
, Carbono
, Oxígeno
, Hidrógeno
, Aldehídos
, Ácidos Grasos
, Monitoreo del Ambiente/métodos