Characteristics of polycyclic aromatic hydrocarbons in food oils in Beijing catering services

Chemical characterization of volatile organic compounds (VOCs) emitted from multiple cooking cuisines and purification efficiency assessments

Cooking process can produce abundant volatile organic compounds (VOCs), which are harmful to environment and human health. Therefore, we conducted a comprehensive analysis in which VOCs emissions from multiple cuisines have been sampled based on the simulation and acquisition platform, involving concentration characteristics, ozone formation potential (OFP) and purification efficiency assessments. VOCs emissions varied from 1828.5 to 14,355.1 µg/m³, with the maximum and minimum values from Barbecue and Family cuisine, respectively. Alkanes and alcohol had higher contributions to VOCs from Sichuan and Hunan cuisine (64.1%), Family cuisine (66.3%), Shandong cuisine (69.1%) and Cantonese cuisine (69.8%), with the dominant VOCs species of ethanol, isobutane and n-butane. In comparison, alcohols (79.5%) were abundant for Huaiyang cuisine, while alkanes (19.7%), alkenes (35.9%) and haloalkanes (22.9%) accounted for higher proportions from Barbecue. Specially, carbon tetrachloride, n-hexylene and 1-butene were the most abundant VOCs species for Barbecue, ranging from 8.8% to 14.6%. The highest OFP occurred in Barbecue. The sensitive species of OFP for Huaiyang cuisine were alcohols, while other cuisines were alkenes. Purification efficiency assessments shed light on the removal differences of individual and synergistic control technologies. VOCs emissions exhibited a strong dependence on the photocatalytic oxidation, with the removal efficiencies of 29.0%-54.4%. However, the high voltage electrostatic, wet purification and mechanical separation techniques played a mediocre or even counterproductive role in the VOCs reduction, meanwhile collaborative control technologies could not significantly improve the removal efficiency. Our results identified more effective control technologies, which were conductive to alleviating air pollution from cooking emissions.

Emission characteristics and quantitative assessment of the health risks of cooking fumes during outdoor barbecuing

Given the increasing popularity of outdoor barbecue activities and the disregard for barbecue fumes, this study systematically investigated barbecue fume emission characteristics for three types of grilled meats. Particulate matter and volatile organic compounds (VOCs) were continuously measured, and polycyclic aromatic hydrocarbons (PAHs) were isolated from the particulate matter. Cooking emission concentrations depended strongly on the type of meat being cooked. Fine particles were the main particles detected in this study. Low and medium-weight PAHs were the dominant species for all cooking experiments. The mass concentration of total VOCs in the barbecue smoke of the three groups showed significant differences (p < 0.05) and was 1667.18 ± 10.49 μg/m³ in the chicken wing group, 904.03 ± 7.12 μg/m³ in the beef steak group, and 3653.37 ± 12.22 μg/m³ in the streaky pork group. The results of risk assessment showed that the toxicity equivalent quality (TEQ) of carcinogenic PAHs in the particulate matter was significantly higher in the streaky pork group than in the chicken wing and beef steak groups. The carcinogenic risk of benzene exceeds the US EPA standard (1.0E-6) in all types of fumes. Although the hazard index (HI) was below one in all groups for noncarcinogenic risks, it was not cause of optimism. We conjecture that only 500 g of streaky pork would exceed the noncarcinogenic risk limit, and the mass required for carcinogenic risk may be less. When barbecuing, it is essential to avoid high-fat foods and strictly control the fat quantity. This study quantifies the incremental risk of specific foods to consumers and will hopefully provide insight into the hazards of barbecue fumes.

Levels and Health Risk Assessment of Polycyclic Aromatic Hydrocarbons in Vegetable Oils and Frying Oils by Using the Margin of Exposure (MOE) and the Incremental Lifetime Cancer Risk (ILCR) Approach in China

A total of 139 vegetable oils and 48 frying oils produced in China were tested for the levels of 15 Environmental Protection Agency-regulated polycyclic aromatic hydrocarbons (PAHs). The analysis was completed by high-performance liquid chromatography-fluorescence detection (HPLC-FLD). The limit of detection and limit of quantitation were ranged between 0.2-0.3 and 0.6-1 μg/kg, respectively. The average recovery was 58.6-90.6%. The highest mean of total PAHs was found in peanut oil (3.31 μg/kg), while the lowest content was found in olive oil (0.39 μg/kg). In brief, 32.4% of vegetable oils exceeded the European Union maximum levels in China. The detected level of total PAHs in vegetable oils was lower than the frying oils. The mean dietary exposure to PAH15 ranged from 0.197 to 2.051 ng BaPeq/kg bw/day. The margin of exposure values was greater than 10,000, and the cumulative probabilities of the incremental lifetime cancer risk of different age groups were less than the priority risk level (10^-4). Therefore, there was no potential health concern for specific populations.

Recent advances in the chemical oxidation of gaseous volatile organic compounds (VOCs) in liquid phase

The chemical oxidation of gaseous volatile organic compounds (VOCs) in liquid phase may possess great advantages in its high removal efficiency, mild conditions, good reliability, wide applicability, and little potential secondary pollution, which has aroused extensive research interests in the past decade. This Overview Article summarizes the latest achievements to eliminate VOCs by chemical oxidation in liquid phase including gas-liquid mass transfer, homogeneous/heterogeneous oxidation, electrochemical oxidation, and coupling technologies. Important research contributions are highlighted in terms of mass transfer, catalytic materials, removal/mineralization efficiency, and reaction mechanism to evaluate their potential industrial applications. The current challenges and future strategies are discussed from the viewpoint of the deep degradation of refractory VOC substrates and their intermediates. It is anticipated that this review will attract more attention toward the development and application of chemical oxidation methods to clear complex industrial organic exhaust gas.

Levels of polycyclic aromatic hydrocarbons in edible and fried vegetable oil: a health risk assessment study

Polycyclic aromatic hydrocarbons (PAHs) are environmental chemicals that are formed due to incomplete combustion of the organic matters, or during heat treatment of the food. The objectives of the present study were first to estimate levels of the 15-priority PAHs in the edible vegetable oil (corn oil, sunflower oil, olive oil, and canola oil) collected from Egypt. Furthermore, the effect of heat treatment on the formation of PAHs in the canola oil was further examined. In addition, dietary intakes and cancer risk among Egyptian consumers were additionally calculated. The achieved results indicated presence of 15-priority PAHs in all examined oil samples. Canola oil had the highest residual concentrations of PAHs compared with the other tested oil species. Heat treatment of canola oil led to a drastic increase in the formed B[a]P (316.55%), total 2-PAHs (322.47%), total 4-PAHs (297.42%), total 8-PAHs (285.26%), and total 15-PAHs (443.32%), respectively. The incremental lifetime cancer risk among the Egyptian population is considered safe when was calculated for all examined oil samples.

Dietary Pattern, Genomic Stability and Relative Cancer Risk in Asian Food Landscape

The incidence of cancer globally is increasing, partly due to lifestyle factors. Despite a better understanding of cancer biology and advancement in cancer management and therapies, current strategies in cancer treatment remain costly and cause socioeconomic burden especially in Asian countries. Hence, instead of putting more efforts in searches for new cancer cures, attention has now shifted to understanding how to mitigate cancer risk by modulating lifestyle factors. It has been established that carcinogenesis is multifactorial, and the important detrimental role of oxidative stress, chronic inflammation, and genomic instability is evident. To date, there is no study linking dietary pattern and genomic stability in cancer risk in the Asian food landscape. Thus, this present review article discusses recent literature on dietary pattern and genomic stability and its relationship with cancer risk in Asia.

Polycyclic and nitro-polycyclic aromatic hydrocarbon pollution characteristics and carcinogenic risk assessment of indoor kitchen air during cooking periods in rural households in North China

Medium-flow atmospheric samplers were used to collect particulate (PM_2.5) and gaseous samples from the indoor kitchen of each of 35 randomly selected rural houses in North China while a meal was being cooked. The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) and 9 nitro-PAHs (NPAHs) in the samples were quantified by high-performance liquid chromatography (HPLC). This study provided the real PAH and NPAH pollution characteristics and carcinogenic risk produced by cooking in rural indoor kitchens in North China. The mean PAH and NPAH concentrations in air in the indoor kitchens during cooking periods were 4049.1 and 1741.6 ng/m³, respectively. The PAH and NPAH concentrations were lower in the particulate phase than the gaseous phase. The mean PAH and NPAH concentrations were much higher for cooking using coal than for cooking using liquefied petroleum gas (LPG) or electricity. The PAH and NPAH benzo[a]pyrene toxic equivalent (TEQ_BaP) concentrations for cooking using coal were 1823.3 and 2760.9 ng/m³, respectively. Lower PAH and NPAH concentrations were found in kitchens with than without range hoods. Range hoods decreased the PAH and NPAH TEQ_BaP concentrations by 68.8% and 61.9%, respectively. Appropriate fuel and ventilation choice will improve air pollution in indoor kitchens during cooking. The results provide important evidence for changing cooking habits and developing policies for cooking in rural China.