Reduction of cooking oil fume exposure following an engineering intervention in Chinese restaurants

Exposure characteristics and risk assessment of air particles in a Chinese hotel kitchen

Background

The hazards of kitchen particles have attracted social attention, but their distribution characteristics and risk assessment are rarely reported.

Objective

To explore the temporal and spatial distribution characteristics of kitchen particles, analyze the variations in characteristics of number concentration (NC), mass concentration (MC), surface area concentration (SAC), and particle size distribution, provide reference indexes for evaluating worker exposure, evaluate the risk of kitchen particles, as well as suggest improvements and control measures.

Patients and methods

Different cooking posts in a Chinese hotel kitchen were selected to monitor exposure to particles, explore the temporal and spatial distribution characteristics of NC, MC, and SAC of particles in the cooking post, analyze changes in the particle size, compare the individual exposure of particles between the cooking and steaming posts, and analyze the correlation between NC, MC, and SAC. Risk assessment of kitchen ultrafine particles was performed using a Nanotool.

Results

The sizes and fluctuation ranges of NC_{10 - 500nm} at cooking posts during lunch preparation and at peak periods were significantly higher than those at the end of the lunch period. The mean values of MC_{10 - 500nm} during the lunch preparation peak and ending periods were 0.149, 0.229, and 0.151 mg m^-3, respectively. The mean values of SAC_{10 - 500nm} were 225, 961, and 466 μm²·cm^-3, respectively. The mode diameter of exposed particles at the cooking post [(34.98 ± 2.33) nm] was higher than that at the steaming post [(30.11 ± 2.17) nm] (P < 0.01). The correlation between SAC_{10 - 500nm} and NC_{10 - 500nm} (r = 0.703) was the strongest. Nanotool gave a hazard rating ratio, exposure rating ratio, and risk ratio of 0.75.

Conclusion

The sizes of the NC, MC, and SAC of the particles at the cooking post were related to the kitchen operations. Since kitchen particles are of high exposure and risk levels, protective measures should be formulated and implemented to deal with them safely.

Organic pollutant exposure and health effects of cooking emissions on kitchen staff in food services

This study was conducted to determine the exposure and health risk to cooking fumes of a total of 88 volunteer kitchen staff aged between 18 and 65 years working in five different kitchens in Ankara. Gas- and particle-phase polycyclic aromatic hydrocarbons (PAHs), and volatile organic compound (VOCs) concentrations were evaluated in the indoor air of 5 kitchens. Serum malondialdehyde (MDA) and superoxide dismutase (SOD) levels were analyzed to determine the oxidative damage as a result of the exposure to cooking fumes among the cooks and waiters. Significant positive relationships were found between serum MDA levels of the hot kitchen workers and indoor chrysene (Chr), indeno(1,2,3-c,d)pyrene (Ind), and total VOC levels. Although the carcinogenic risks estimated for the exposed population were between the acceptable/tolerable levels, the hazard quotient (HQ) estimated for the exposure to indoor benzene exceeded the safe level. The results of the study revealed that exposure to organic pollutants in indoor air may be a risk factor for the development of oxidative stress, especially in hot kitchen workers. The importance of efficient ventilation in the kitchen has been pointed out to reduce health risks caused by cooking fumes.

Indoor Air Pollution Increases the Risk of Lung Cancer

(1) Background: Cooking and burning incense are important sources of indoor air pollutants. No studies have provided biological evidence of air pollutants in the lungs to support this association. Analysis of pleural fluid may be used to measure the internal exposure dose of air pollutants in the lung. The objective of this study was to provide biological evidence of indoor air pollutants and estimate their risk of lung cancer. (2) Methods: We analyzed 14 common air pollutants in the pleural fluid of 39 cases of lung adenocarcinoma and 40 nonmalignant controls by gas chromatography-mass spectrometry. (3) Results: When we excluded the current smokers and adjusted for age, the adjusted odds ratios (ORs) were 2.22 (95% confidence interval CI = 0.77-6.44) for habitual cooking at home and 3.05 (95% CI = 1.06-8.84) for indoor incense burning. In females, the adjusted ORs were 5.39 (95% CI = 1.11-26.20) for habitual cooking at home and 6.01 (95% CI = 1.14-31.66) for indoor incense burning. In pleural fluid, the most important exposure biomarkers for lung cancer were naphthalene, ethylbenzene, and o-xylene. (4) Conclusions: Habitual cooking and indoor incense burning increased the risk of lung adenocarcinoma.

Association of Particulate Matter from Cooking Oil Fumes with Heart Rate Variability and Oxidative Stress

Many studies have reported various cardiovascular autonomic responses to ambient particulate matter (PM) pollution, but few have reported such responses to occupational PM exposures. Even fewer have demonstrated a relationship between PM pollution and oxidative stress in humans. This panel study evaluates the association between occupational exposure to PM in cooking oil fumes (COFs), and changes in both heart rate variability (HRV) and oxidative stress responses in 54 male Chinese cooks. Linear mixed-effects regression models were adopted to estimate the strength of the association between PM and HRV. Participants' pre- and post-workshift urine samples were analyzed for 8-hydroxy-2'-deoxyguanosine (8-OHdG) and malondialdehyde (MDA). Exposure to PM in COFs from 15 min to 2 h were associated with a decrease in HRV and an increase in heart rate among cooks. The urinary 8-OHdG levels of cooks were significantly elevated after workshift exposure to COFs. The levels of PM2.5, PM1.0, and particulate benzo(a)pyrene in COFs were all positively correlated with cross-workshift urinary 8-OHdG levels. Furthermore, the levels of benzo(a)pyrene in COFs were positively correlated with cross-workshift urinary MDA levels. The effects of COFs on HRV were independent of cross-workshift urinary 8-OHdG levels. Exposure to COFs leads to disturbed autonomic function and an increased risk of oxidative DNA injury among cooks in Chinese restaurants.

Characterizations of PM2.5-bound organic compounds and associated potential cancer risks on cooking emissions from dominated types of commercial restaurants in northwestern China

Cooking emissions are both indoor and outdoor sources for fine particulate matter (PM2.5) but their contributions are often ignored. The PM2.5-bound organic compounds, including alkanols, alkanes, monocarboxylic acids, dicarboxylic acids, and polycyclic aromatic hydrocarbons (PAHs) were determined in the emissions from the most popular types of restaurants in the capital city of northwestern China. The mean concentration of total quantified organic compounds (Σ_{PM_O}) ranged from 1112 to 32,016 ng m-3, with the maximum for the Chinese barbecue restaurants. The Σ_{PM_O} accounted for an average of 11% of PM_2.5 mass, demonstrating their significances in the cooking emissions. Hexadecanoic acid (C₁₆) and 1-hexadecanol (C₁₆) were considered as the tracers for stir-frying, steaming, and boiling which are usually applied in the traditional Chinese cuisines; 1-undecanol (C₁₁), 9-fluorenone, and indeno[1,2,3-cd]pyrene were found to be potential markers for grilling and deep-frying which are widely applied in the Western style cooking method. The PAH diagnostic ratios also illustrated their representatives to distinguish the emissions from traditional Chinese cuisines and the Western-style restaurants. The estimated carcinogenic risks for the restaurants that consumed a large amount of oils and employed high temperature cooking methods (e.g., barbecuing and deep-frying) were 2.6-4.2 times exceeded the international safety limit. The organic profiles obtained in this study could be contributed to refine PM_2.5 source apportionment in urban areas in northwestern China. The estimations of potential cancer risks urge the establishment of more stringent legislations to protect the health of the catering staffs.

Biomarkers and indoor air quality: A translational research review

Introduction:

Air pollution is linked to mortality and morbidity. Since humans spend nearly all their time indoors, improving indoor air quality (IAQ) is a compelling approach to mitigate air pollutant exposure. To assess interventions, relying on clinical outcomes may require prolonged follow-up, which hinders feasibility. Thus, identifying biomarkers that respond to changes in IAQ may be useful to assess the effectiveness of interventions.

Methods:

We conducted a narrative review by searching several databases to identify studies published over the last decade that measured the response of blood, urine, and/or salivary biomarkers to variations (natural and intervention-induced) of changes in indoor air pollutant exposure.

Results:

Numerous studies reported on associations between IAQ exposures and biomarkers with heterogeneity across study designs and methods. This review summarizes the responses of 113 biomarkers described in 30 articles. The biomarkers which most frequently responded to variations in indoor air pollutant exposures were high sensitivity C-reactive protein (hsCRP), von Willebrand Factor (vWF), 8-hydroxy-2′-deoxyguanosine (8-OHdG), and 1-hydroxypyrene (1-OHP).

Conclusions:

This review will guide the selection of biomarkers for translational studies evaluating the impact of indoor air pollutants on human health.

Semen quality and sperm DNA damage associa -revised - final-finalted with oxidative stress in relation to exposure to polycyclic aromatic hydrocarbons

The cross-sectional study aimed to assess whether oxidative stress induced by exposure to polycyclic aromatic hydrocarbons (PAHs) affect semen quality and sperm DNA integrity. A total of 106 who met the inclusion criteria, were recruited from a coke-oven plant during their annual health checkup. The human subjects were grouped into the high exposure group, the low exposure group and the control based on PAH concentrations surrounding their employment locations. Semen quality, oxidative stress status, and sperm DNA damage [DNA fragmentation and 8-hydroxy-2'-deoxyguanosine (8-oxodGuo)] were assessed. Urinary 1-hydroxypyren (1-OHP) was used to assess human subject exposure to PAHs. The high exposure group experienced significantly lower sperm motility and normal morphology than the control (P = 0.046 and 0.049, respectively). The high exposure group also had significantly higher 8-oxoGuo concentrations in sperm than the control (P = 0.027). Urinary 1-OHP concentration was associated with decreased motility and less normal morphology, along with increased sperm oxidative damage and ROS concentrations. Oxidative stress induced by exposure to PAHs was associated with decreased sperm quality.

Role of Chinese cooking emissions on ambient air quality and human health

Chinese-style cooking often involves volatilization of oils which can potentially produce a large number of pollutants, which have adverse impact on environment and human health. Therefore, we have reviewed 75 published studies associated with research topic among Mainland China, Hong Kong and Taiwan, involving studies on the roles of food ingredients and oil type, cooking style impacting on generated pollutants, and human health. The highest concentration occurred including: 1) when peat, wood, and raw coal were used in stoves; 2) olive oil was adopted; 3) cooking with high temperatures; and 4) without cleaning technology. We conclude that PM concentrations for cooking emissions were between 0.14 and 24.46mg/cm³. VOC concentrations varied from 0.35 to 3.41mg/m³. Barbeque produced the greatest mass concentrations compared to Sichuan cuisine, canteen and other restaurants. The PAHs concentration emitted from the exhaust stacks, dining area and kitchen ranged from 0.0175μg/m³ to 83μg/m³. The largest amount of gaseous pollutants emitted was recorded during incomplete combustion of fuel or when a low combustion efficiency (CO2/ (CO+CO2)<0.5) was observed. The variation range was 6.27-228.89mg/m³, 0.16-0.80mg/m³, 0.69-4.33mg/m3, 0.70-21.70mg/m³ for CO, CO₂, NO₂ and SO₂ respectively. In regards to the toxicity and exposure, current findings concluded that both the dose and exposure time are significant factors to be considered. Scientific research in this area has been mainly driven by comparison among emissions from various ingredients and cooking techniques. There is still a need for more comprehensive studies to fully characterise the cooking emissions including their physical and chemical transformations which is crucial for accurate estimation of their impacts on the environment and human health.

Exposure to cooking oil fumes and oxidative damages: a longitudinal study in Chinese military cooks

Cooking oil fumes (COF) contain polycyclic aromatic hydrocarbons (PAHs), heterocyclic aromatic amines, benzene, and formaldehyde, which may cause oxidative damages to DNA and lipids. We assessed the relations between exposure to COF and subsequent oxidative DNA damage and lipid peroxidation among military cooks and office-based soldiers. The study population, including 61 Taiwanese male military cooks and a reference group of 37 office soldiers, collected urine samples pre-shift of the first weekday and post-shift of the fifth workday. We measured airborne particulate PAHs in military kitchens and offices and concentrations of urinary 1-OHP, a biomarker of PAH exposure, urinary 8-hydroxydeoxyguanosine (8-OHdG), a biomarkers of oxidative DNA damage, and urinary isoprostane (Isop). Airborne particulate PAHs levels in kitchens significantly exceeded those in office areas. The concentrations of urinary 1-OHP among military cooks increased significantly after 5 days of exposure to COF. Using generalized estimating equation analysis adjusting for confounding, a change in log(8-OHdG) and log(Isop) were statistically significantly related to a unit change in log(1-OHP) (regression coefficient (β), β=0.06, 95% CI 0.001-0.12) and (β=0.07, 95% CI 0.001-0.13), respectively. Exposure to PAHs, or other compounds in cooking oil fumes, may cause both oxidative DNA damage and lipid peroxidation.