Grilling Of Meat Research Articles

Cooking as an organic aerosol source leading to urban air quality degradation

Air quality degradation events in the urban environment are often attributed to anthropogenic aerosol sources related to combustion of liquid or solid fuels in various activities. The effects of massive cooking emissions during Greek nationwide traditional festivities were investigated by a combined characterization of particulate matter (PM) levels and organic aerosol (OA) sources. Focus was centered on periods around two major festivities, namely “Fat Thursday” and Easter Sunday along six different years. OA sources were apportioned through Positive Matrix Factorization (PMF) on Aerosol Chemical Speciation Monitor (ACSM) mass spectra, while the spatial characteristics of the episodes were assessed through a low-cost, sensor-based PM2.5 monitoring network operating in Athens and other Greek cities. Contrasts were examined by considering a 15-day period around each event, while the effect of the 2020–2021 mobility restrictions, related to COVID-19, was also assessed. An episode-specific cooking organic aerosol (COA) spectral profile was delineated, and can be considered as a reference for ambient COA from meat grilling. Severe pollution episodes that affected the entire Athens basin were recorded, with PM2.5 concentrations exceeding 300 μg m−3 on occasions. COA contributions dominated primary organic aerosol (POA) and made up almost half of OA concentrations. During “Fat Thursday” COA concentrations and contributions peaked during night-time (23.2 μg m−3 and 46 %, respectively) while for Easter Sunday COA maxima were recorded in the early afternoon (27.4 μg m−3 and 39 %). Analyzing a full-year OA source dataset, revealed a pronounced recreational cooking pattern in central Athens, with COA concentrations rising towards the weekend, reflecting the impact of the food service sector. In view of the upcoming review of the EU air quality directive, foreseeing stricter annual PM2.5 limits as well as 24-h limit values and related alerts, the mitigation of cooking emissions appears as a potent instrument for achieving tangible air quality benefits.

Hardware Engineering of Hazardous Gas and Alcoholic Substances Detector in Meat Using Microcontroller and Gas Sensor

Meat may provide not only essential nutritional content but also possible harmful effects on human bodies. Unsafe consumption of meat potentially triggers colorectal cancer risks. Grilling is the most popular way to consume meat. However, meat grilling triggers the formation of hazardous chemical substances such as poisonous Polycyclic Aromatic Hydrocarbons (PAHs). This study conducted experiments using hardware engineering with microcontrollers and different gas sensors, aiming to identify gas substances produced by meat during grilling. The hardware prototype for the test simulation tool was assembled with integrated block systems and circuits. Evaluations were conducted on the direct grilling of three different types of meat. The data results were then utilized to analyze gas substances produced by meat during direct grilling. Based on the results, only five of the seven MQ-type gas sensors used in the research reacted to gas substances produced by all types of meat: LPG, alcohol, carbon monoxide, methane, and carbon dioxide, which were successfully detected in meat during grilling. Our research contributes to discovering a potential prevalence of increased alcoholic content in meat that has been grilled for five minutes. This finding is especially crucial for Muslims since it is highly correlated with halal certification of meat consumption. According to the results, Muslims should wait at least seven minutes or more after direct grilling to let the alcoholic content in meat thoroughly decrease so that it can be safely certified as halal to be consumed according to Islamic laws. Doi: 10.28991/HIJ-2023-04-03-01 Full Text: PDF

Gendered Foods and Traditions among Argentine Jewry

:Examining layers of meaning found in personal stories, folktales, memoirs, recipes, and cookbooks collected from interviewees in Argentina and in Israel, this essay interprets the women's role in Jewish-Argentine identity formation and preservation in connection to processes of forming private and collective memory. Traditional Jewish foodways generally and gefilte-fish specifically in contrast to traditional Argentine foodways such as meat grilling are analyzed as a symbolic praxis that strengthens Argentine identity.

Dietary patterns, cooking methods and breast cancer risk in Mexico: An exploratory case-control study.

Background: Nutrition has an important influence on the risk of developing breast cancer (BC). Dietary patterns can capture the complex interplay of nutrients and cooking methods can contribute to the presence of heterocyclic amines, which are potent mammary carcinogens. Research on dietary patterns, cooking methods, and their association with BC in Mexican women is scarce. Aim: To evaluate the association of dietary patterns and cooking methods with BC risk among women from the Northwest region of Mexico. Methods: This case-control study included 120 women. Eligible cases (n = 60) were diagnosed and biopsy-confirmed in the past 2 years. Control subjects (n = 60) were hospital and population-based. Dietary intake and cooking methods were respectively assessed through a food frequency questionnaire (FFQ) and the National Cancer Institute survey. We obtained dietary patterns from a K-means cluster analysis (CA), and multivariate logistic regression tested the association of dietary patterns and cooking methods with BC risk. Results: Prudent and caloric dietary patterns were identified. The caloric pattern was associated with BC risk (Model 1: ORadj: 5.07, 95%CI:1.44-17.84, p = 0.011; Model 2: ORadj: 4.99 (95%CI:1.39-17.92, p = 0.014). Intense frying, meat grilling and poultry resulted in a significant BC risk (Model 1: ORadj: 5.54,95%CI: 2.13-14.41), p < 0.001; Model 2: ORadj: 5.12, 95%CI: 1.83-14.31, p = 0.002). At Oestrogen exposure of <32 years, there was an association between dietary patterns and BC risk (ORadj: 4.69, 95%CI: 1.01-21.92, p = 0.049). The relationship between BC risk and cooking intensity was found in both strata of exposure to oestrogens: <32 years (ORadj: 3.72, 95%CI:1.04-13.33, p = 0.044), and ≥32 years (ORadj: 6.06, 95%CI:1.34-27.42, p = 0.019). Conclusions: A caloric dietary pattern rich in refined carbohydrates and saturated fat, and intense meat product cooking may increase the risk of BC in Mexican women.

Inhalation risk to PAHs and BTEX during barbecuing: The role of fuel/food type and route of exposure

The manuscript presents an innovative and holistic approach to quantifying PAHs and BTEX emissions from the grilling process and indicates a novel driven–toxicity-based solution to recognize health effects related to BBQ emissions. The exposure scenario includes the type of grilling device, food type, and individual attitudes, but also a keen understanding of the broad health implications related to the gaseous/particulate PAHs emission, or age-related effects. The calculated incremental lifetime cancer risk (ILCR) associated with the exposure to PAH congeners and BTEX indicates an unacceptable level in the case of charcoal and briquette grilling with the highest values for professional cooks. The sum of 15 PAH concentrations in grilled foods was highest for meat grilling over charcoal briquettes – 382,020.39 ng/m3 and lowest for meat grilling on a gas grill – 1442.16 ng/m3. The emissions of BTEX from lump charcoal grilling were 130 times higher compared to the gaseous grill. In all considered scenarios lump-charcoal and charcoal briquettes grilling derive the ILCR above the 10−4, indicating negative effects of traditional grills on human health. The paper completes knowledge of wide-ranging health implications associated with BBQs, a topic that is almost completely unaddressed among the scientific community and policymakers.

Outdoor charcoal grilling: Particulate and gas-phase emissions, organic speciation and ecotoxicological assessment

Charbroiling is a major source of air pollution worldwide. In this study, the particulate and gas-phase emissions from the charcoal lighting phase and during the grilling of meat (pork and rump cap) and fish (sardine and salmon) on an outdoor barbecue grill were characterized. Some gaseous compounds (ethane, hexane, NO2, N2O, SO2, NH3, HCl) did not display significant variations between samples and the background level, indicating that they are not emitted during barbecuing. During the charcoal heating phase, levels of total volatile organic compounds (TVOCs) increased 6 times above the background value. Four-to 5-fold increases in TVOC concentrations were observed when grilling sardines and salmon, while rises of 1.3–1.5 were recorded for meat. Emission factors of 32.4 g PM10 kg−1 and 22.7 g TVOCs kg−1 were obtained for the biofuel ignition phase. PM10 emission rates of 472, 531, 1104 and 918 mg kg−1 were estimated for pork, rump cap, sardine and salmon charbroiling, respectively. TVOC emissions ranged from 23.9 mg kg−1 (pork) to 82.6 mg kg−1 (salmon). Organic carbon accounted for 35.0% of the PM10 emitted during the ignition and flaming phases of the biofuel but represented mass fractions of 56–64% of the particulate emissions during food charbroiling. About 235 organic compounds were quantified in the PM10 samples. The ecotoxicity was assessed using the kinetic version of the Vibrio fischeri bioluminescence inhibition bioassay. All samples were classified as very toxic or toxic. Ecotoxicity was statistically correlated with several n-alkanes, PAHs and alkyl-PAHs, anhydrosugars, acids, and phenolic compounds.

Assessing Impacts of Additives on Particulate Matter and Volatile Organic Compounds Produced from the Grilling of Meat

Cooking fumes are an important source of volatile organic compounds (VOCs), particulate matter (PM), and carbonyl compounds. The additive is wildly applied in grilling meat for flavor improvement. However, the effects of additives on cooking fumes emissions, such as volatile organic compounds (VOCs), particulate matter (PM), and carbonyl compounds, in meat grilling have not been studied. The impact of four additives, including white pepper, salt, garlic powder, and compound marinade, on the emission characteristics of cooking fumes from the grilling meat was investigated. The concentrations of VOCs and carbonyl compounds in the cooking fumes were analyzed by TD-GC/MS and HPLC, respectively. The PM emission characteristics (mass concentration and size distribution) were measured by DustTrak DRX aerosol monitor in real-time. Results showed that the application of white pepper, salt, garlic powder, and mixed spices could significantly reduce the total particles mass concentration (TPM) emissions during meat-grilling by 65.07%, 47.86%, 32.87%, and 56.01%, respectively. The mass concentration of PM during meat-grilling reached maximum values ranging from 350 to 390 s and gradually fell at the final stages of grilling. The total concentration of 22 representative VOCs emitted from the grilling was significantly increased in grilling meat marinated with compound additives. Aromatic hydrocarbons were the predominant VOCs species, followed by ketone compounds. During the grilling process, formaldehyde, acetaldehyde, propionaldehyde, and acetone were major carbonyl compounds. The low molecular weight carbonyl compounds (C1–C3) in cooking fumes were dominant carbonyl compounds.

Emission characteristics of particulate matter, odors, and volatile organic compounds from the grilling of pork

Meat-grilling restaurants are considered to be residential emission sources of air pollutants. To investigate the emission characteristics of particulate matter (PM), odors, and volatile organic compounds (VOCs) from the grilling of meat, a grilling apparatus equipped with butane gas burners was used to grill pork belly and marinated pork ribs in a laboratory setting. When grilling the pork belly, the emission factor for PM with a diameter of 2.5 μm or below (PM2.5) was 754 mg-PM·kg-meat−1, accounting for 99% of total suspended particles (TSPs), while that of the marinated pork ribs was 137 mg-PM·kg-meat−1 (96% of TSPs). Ammonia and acetaldehyde were the most common odors emitted during grilling at 43–88 mg·kg-meat−1 and 22–30 mg·kg-meat−1, respectively. Aldehydes were the most significant contributor to total odor intensity (36%–67%). Benzene, vinyl acetate, and hexene were the most abundant VOCs for the pork belly, while butane, vinyl acetate, and n-dodecane were the most abundant for the marinated ribs. Among the VOCs emitted from the pork grilling process, hexene, butane, and toluene were the dominant ozone precursors. The information obtained in this study is useful for furthering the understanding of the characteristics of air pollutants emitted from actual meat-grilling restaurants. Additionally, knowledge of the PM, odor, and VOC emission characteristics and their emission factors is useful for establishing management strategies for air pollutants from meat-grilling restaurants.

Characterization of stakeholders and grilling practices of chicken meat sold in south of Benin Republic

Chicken meat grilling is an economic activity growing in major cities of Benin. This study aimed to characterize stakeholders and grilling processes of chicken meat sold in southern Benin. Therefore, a survey was conducted at the cities of Cotonou and Abomey-Calavi in Benin, with main categories of stakeholders involved in that activity. It revealed that this sector included spice and skewer producers, frozen chicken, skewer and spice retailers, grilling processors and consumers. Commercial chicken grilling was predominantly male activity, mostly Nigerians (61%), followed by Nigeriens (31%) and Beninese (8%), in which subgroups existed. A typology of consumers showed two groups which were: adolescents, under training (22%) and adults, visitors of pubs (78%). The grilling process depended on whether it was a whole chicken or chicken pieces on skewers. The grilling devices were barrel grill (67%), charcoal cabinet, type grill (25%) and gas cabinet type grill (8%). Grilling temperature and time of whole chickens were not significantly different between the grills, except for skewers having shorter grilling time (26 min). Precooked chickens had a better yield (84%) than those grilled directly (57%), it did not vary significantly between the barrel grill and the gas cabinet type grill. These grilling parameter differences may affect the quality of grilled chicken meat. Keywords : Grilled chicken, materiel, process, typology, grilling processors, consumers

Evaluation of odor emission characteristics and contribution of meat grilling restaurants

Evaluation of odor emission characteristics and contribution of meat grilling restaurants

Continuous measurement of contact heat flux during minced meat grilling

Few studies concerning contact heating of food products were found in the literature despite the importance of this mode of heat transfer in many operations (grilling, pan-frying) and its drastic impact on product quality change during heating. An original heating device to measure continuously contact heat flux and heating surface temperature was therefore developed and applied to the contact heating of turkey meat with a heating surface at 128°C, 215°C and 255°C. Based on the experimental results obtained, a simplified heat transfer model was developed and allowed the calculation of the parts of the total energy received by the product (i) used to raise its temperature (ii) used to evaporate water exuding from its lower surface during heating and (iii) lost by heat exchange with the surroundings. In the experimental conditions covered by our experiments, the part of energy used to evaporate water exuding from the product was found to vary between 55% and 67% of the total energy received. The precise evaluation of the kinetics of variation of the contact heat transfer coefficient (quantifying the quality of thermal contact between the lower surface of the meat sample and the heating plate) was also made possible. At 215°C and 255°C, this coefficient ranged from 500 to 100 W⋅m−2⋅K−1 between the start and the end of the cooking, these values being in the same order of magnitude as those measured in previous studies concerning single-faced grilling of meat.

Diet contains carcinogens and deficiency of vitamin C determines the level of oxidative DNA damage among Jakarta toll collectors

Consuming meat food products that undergo high-temperature combustion is able to provide opportunities exposed to carcinogenic substances and leads to oxidative stress. Oxidative stress is also a precondition for the occurrence of DNA damage and cancer can be detected by the presence of 8- hydroxy-'2-deoxyguanosine (8OHdG). The study aimed to investigate whether the high prevalence of oxidative stress in Jakarta highway toll collector is independently or causally implicated in deficiency of vitamin C and the grilled food as the third factor modified the association. A cross-sectional study and urinary 8-OHdG was detected using the Enzyme-Link Immunosorbent Assay (ELISA) method on 161 toll gate collectors. The study found a strong relationship between grilled food and 8-OHdG (p-value 0.037); prevalence risk ratio (PRR) 2.01 (95% CI 1.044-3.890). However, relationship between variable vitamin C and the 8-OHdG stratified by grilled food founded inverse negatively, it was due to the high frequency of subjects 8-OHdG presented significantly with the deficiency of vitamin C. There was not enough intake of vitamin C among people who ate grilled food. Mantel-Haenzel formula was calculated and the estimation found the condition of independence from the test were X2MH=0.843 among the group who consumed the grilled food. The association between intake of grilled food and oxidative stress is the mere result of the effect of deficiency of vitamin C. Special attention should be given to minimize diet containing various carcinogens like the meat grilling process with a high temperature to decrease degenerative diseases and cancer risk in sub-population with high expose to air pollution.

Influence of chosen pre- and post-slaughter factors on heme iron content in selected beef muscles of crossbred bulls and steers

ABSTRACTThe experiment aimed to assess the effect of selected factors on the content of heme iron (FeH) in beef muscle. The research material included selected beef muscles acquired from steers and bulls obtained by crossing dairy cows with meat-bred bulls (Limousin, Charolais, Hereford). Analysis of the preslaughter factors showed a significant effect of paternal breed, slaughter age, diet, and hormonal status of animals on the content of FeH (α = 0.05). Significantly more FeH was observed in longissimus lumborum derived from older animals. Regarding paternal breed, higher FeH content was observed in the glutes medius muscle obtained from Herefords, compared with Charolais and Limousin. Furthermore, meat obtained from bulls and semi-intensively fed animals contained more FeH compared with meat obtained from steers and intensively fed animals. In the preparation process, FeH content significantly decreased during meat aging, meat grilling also caused a loss of FeH by approximately 19% on average.

Temporal evolution of ultrafine particles and of alveolar deposited surface area from main indoor combustion and non-combustion sources in a model room

Aerosol number size distributions, PM mass concentrations, alveolar deposited surface areas (ADSAs) and VOC concentrations were measured in a model room when aerosol was emitted by sources frequently encountered in indoor environments. Both combustion and non-combustion sources were considered. The most intense aerosol emission occurred when combustion sources were active (as high as 4.1×107particlescm−3 for two meat grilling sessions; the first with exhaust ventilation, the second without). An intense spike generation of nucleation particles occurred when appliances equipped with brush electric motors were operating (as high as 106particlescm−3 on switching on an electric drill). Average UFP increments over the background value were highest for electric appliances (5–12%) and lowest for combustion sources (as low as −24% for tobacco cigarette smoke). In contrast, average increments in ADSA were highest for combustion sources (as high as 3.2×103μm2cm−3 for meat grilling without exhaust ventilation) and lowest for electric appliances (20–90μm2cm−3). The health relevance of such particles is associated to their ability to penetrate cellular structures and elicit inflammatory effects mediated through oxidative stress in a way dependent on their surface area.The highest VOC concentrations were measured (PID probe) for cigarette smoke (8ppm) and spray air freshener (10ppm). The highest PM mass concentration (PM1) was measured for citronella candle burning (as high as 7.6mgm−3).

Effect of selected local spices marinades on the reduction of heterocyclic amines in grilled beef (satay)

The present study focused to investigate the effect of some selected spices (turmeric, torch ginger, lemongrass and curry leaves) on the formation of heterocyclic amines (HCAs, IQx, MeIQ, MeIQx, DiMeIQx, IQ, norharman, harman and AαC) in grilled satay (beef). Satay samples were marinated with 1–4 g/100 g concentration of turmeric and 2.5–10 g/100 g concentration of torch ginger, lemongrass and curry leaves, at different medium (70 °C) and well done (80 °C) doneness cooking temperatures. The concentration of HCAs in grilled satay samples were analysed using LC/MS technique. The results have shown that turmeric reduced maximum 82 ng/100 g level of IQ (11.43 ± 0.53 to 2.05 ± 0.18 ng/g) at 4 g/100 g concentration at medium doneness and 44.4 ng/100 g level was reduced of IQ, when satay was marinated with 10 g/100 g lemongrass concentration at medium doneness. The highest level of MeIQX was reduced to 83 ng/100 g of satay meat marinated in 10 g/100 g torch ginger at medium doneness. Curry leaves with 10 g/100 g concentration marinated beef meat was reduced the level of IQ 78.5 at medium doneness. The use of local spices in marinating of grilled beef will certainly inhibit/reduce the level of toxic and harmful HCAs. Significance of results for industryThe use of native spices during grilling of meat will minimize the formation of heterocyclic amines and therefore will help to avoid toxic and carcinogenic effects from these toxins.

Plume characterization of a typical South African braai

To braai is part of the South African heritage that transcends ethnic barriers and socio-economic groups. In this paper, a comprehensive analysis of atmospheric gaseous and aerosol species within a plume originating from a typical South African braai is presented. Braai experiments were conducted at Welgegund – a comprehensively equipped regional background atmospheric air quality and climate change monitoring station. Five distinct phases were identified during the braai. Sulphur dioxide (SO 2 ), nitrogen oxides(NO x ) and carbonmonoxide (CO) increased significantly, while ozone (O 3 ) did not increase notably. Aromatic and alkane volatile organic compounds were determined, with benzene exceeding the 2015 South African one-year ambient air quality limit. A comparison of atmospheric PM 10 (particulate matter of an aerodynamic diameter ≤10 μm) concentrations with the 24-hour ambient limit indicated that PM 10 is problematic during the meat grilling phase. From a climatic point of view, relatively high single scattering albedo (ω o ) indicated a cooling aerosol direct effect, while periods with lowerω o coincided with peak black carbon (BC) emissions. The highest trace metal concentrations were associated with species typically present in ash. The lead (Pb) concentration was higher than the annual ambient air quality limit. Sulphate (SO 4 2– ), calcium (Ca 2+ ) and magnesium (Mg 2+ ) were the dominant water-soluble species present in the aerosols. The largest number of organic aerosol compounds was in the PM 2.5–1 fraction, which also had the highest semi-quantified concentration. The results indicated that a recreational braai does not pose significant health risks. However, the longer exposure periods that are experienced by occupational vendors, will significantly increase health risks. KEYWORDS Braai (barbeque), atmospheric gaseous species, aerosols, atmospheric organic compounds, optical properties, chemical properties.

Determination of volatile nitrosamines in grilled lamb and vegetables using comprehensive gas chromatography – Nitrogen chemiluminescence detection

The grilling of meat may generate dangerous levels of mutagenic and carcinogenic nitrosamines (NAs). Meat and vegetable samples underwent a two-step solid-phase extraction before analysis by comprehensive gas chromatography with a nitrogen chemiluminescence detection system (GCxGC-NCD). The GCxGC-NCD method showed high selectivity, sensitivity and equimolarity in its response to six specific NAs. NA contamination of charcoal-grilled lamb at various stages of cooking and with various fat contents and also charcoal-grilled vegetables were investigated. The grilling of lamb on unready charcoal resulted in the formation of considerable quantities of NAs. Grilling lamb on properly prepared, ready charcoal resulted in an increase in total concentrations of six NAs from 0 to 4.51μgkg−1 over a period of 16min. Increasing the fat content of the grilled lamb from 5% to 20% caused a modest increase in total concentrations of the six investigated NAs from 4.51 to 5.30μgkg−1.

Application of the BRAFO tiered approach for benefit–risk assessment to case studies on heat processing contaminants

The aim of the European Funded Project BRAFO (benefit–risk analysis of foods) project was to develop a framework that allows quantitative comparison of human health risks and benefits of foods based on a common scale of measurement. This publication describes the application of the BRAFO methodology to three different case studies: the formation of acrylamide in potato and cereal based products, the formation of benzo(a)pyrene through smoking and grilling of meat and fish and the heat-treatment of milk. Reference, alternative scenario and target population represented the basic structure to test the tiers of the framework.Various intervention methods intended to reduce acrylamide in potato and cereal products were evaluated against the historical production methods. In conclusion the benefits of the acrylamide-reducing measures were considered prevailing.For benzo(a)pyrene, three illustrated alternative scenarios were evaluated against the most common smoking practice. The alternative scenarios were assessed as delivering benefits, introducing only minimal potential risks.Similar considerations were made for heat treatment of milk where the comparison of the microbiological effects of heat treatment, physico-chemical changes of milk constituents with positive and negative health effects was assessed. In general, based on data available, benefits of the heat treatment were outweighing any risks.

Distillers grains do not change carcass composition but change some fatty acids when added to finishing diet (2009)

Introduction Distillers grains are a by-product of ethanol production and have become increasingly available in recent years. Some research has revealed negative effects of distillers grains on quality and yield grades. Distillers grains contain substantial amounts of unsaturated fats and therefore could alter the ratios of saturated and unsaturated fats to achieve a more desirable composition in beef. Heterocyclic amines are the carcinogenic compounds released during high-temperature grilling of meat and would be increased if fat composition is changed. Our objectives were to evaluate effects of feeding distillers grains on carcass fatness, fatty acid profiles, and formation of heterocyclic amines.

Measurement of genotoxic air pollutant exposures in street vendors and school children in and near Bangkok

The effects of air pollution on human health are a great concern, particularly in big cities with severe traffic problems such as Bangkok, Thailand. In this study, exposure to genotoxic compounds in ambient air was studied by analysis of particle-associated polycyclic aromatic hydrocarbons (PAHs) and benzene through direct measurement of concentrations in air as well as through the use of different biomarkers of exposure: urinary 1-hydroxypyrene (1-OHP) for PAHs and urinary t,t-muconic acid ( t,t-MA) for benzene. The study was conducted in various susceptible groups of the population with different occupations in 5 traffic-congested areas of Bangkok, as well as in primary school children. The level of total PAHs on the main roads at various sites ranged from 7.10 to 83.04 ng/m 3, while benzene levels ranged from 16.35 to 49.25 ppb. In contrast, ambient levels in nearby temples, the control sites, ranged from 1.67 to 3.04 ng/m 3 total PAHs and 10.16 to 16.25 ppb benzene. Street vendors selling clothes were exposed to 16.07 ± 1.64 ng/m 3 total PAHs and 21.97 ± 1.50 ppb benzene, levels higher than in monks and nuns residing in nearby temples (5.34 ± 0.65 ng/m 3 total PAHs and 13.69 ± 0.77 ppb benzene). Grilled-meat vendors in the same area were exposed to both total PAHs and benzene at even higher levels, possibly due to additional formation of PAHs during the grilling of meat (34.27 ± 7.02 ng/m 3 total PAHs; 27.49 ± 2.72 ppb benzene). At the end of the workday, urinary 1-OHP levels in street vendors (0.12 and 0.15 μmol/mol creatinine in clothes and grilled-meat vendors, respectively) were significantly higher than in controls (0.04 μmol/mol creatinine; P < 0.01). Afternoon urinary t,t-MA levels in both groups of street vendors (0.12 mg/g creatinine) were also significantly higher than in controls (0.08 mg/g creatinine; P < 0.05). School children from two schools in Bangkok were exposed to total PAHs and benzene at levels of 6.70 ± 0.47 ng/m 3 and 4.71 ± 0.25 ppb, respectively, higher than those to which children living outside the city were exposed (1.25 ± 0.24 ng/m 3 total PAHs; 2.10 ± 0.16 ppb benzene). At the end of the school day, levels of urinary 1-OHP and t,t-MA were significantly higher ( P < 0.001 and P < 0.01, respectively) in Bangkok school children (0.23 μmol/mol creatinine and 0.27 mg/g creatinine, respectively) than in school children from outside Bangkok (0.10 μmol/mol creatinine and 0.08 mg/g creatinine, respectively).