Health risk assessment of occupational exposure to particulate-phase polycyclic aromatic hydrocarbons associated with Chinese, Malay and Indian cooking

Chemical Characterization and Influencing Factors of Gaseous and Particulate Components in Cooking Oil Fume (COF) from Traditional Chinese Dishes: Insights from High-Resolution Mass Spectrometry

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.

Biomonitoring polycyclic aromatic hydrocarbon levels in domestic kitchens using commonly grown culinary herbs

Cooking is a significant source of polycyclic aromatic hydrocarbon (PAHs) emissions in indoor environments. A one-month biomonitoring study was carried out in previously selected rural Hungarian kitchens to evaluate cooking-related PAHs concentrations in 4 common kitchen vegetables such as basil, parsley, rocket and chives. The study had two mainobjectives: firstly, to follow PAHs accumulation pattern and to find out if this pattern can be associated with different cooking habits. Also, the usefulness of culinary herbs for indoor bioaccumulation studies was assessed. The 2-ring naphthalene was the dominant PAH in the majority of the samples, its concentrations were in the range of 25.4 µg/kg and 274 µg/kg, of 3-ring PAHs the prevalency of phenanthrene was observed, with highest concentration of 62 µg/kg. PAHs accumulation pattern in tested plants clearly indicated differences in cooking methods and cooking oils used in the selected households. Use of lard and animal fats in general resulted in the high concentrations of higher molecular weight (5- and 6-ring) PAHs, while olive oil usage could be associated with the emission of 2- and 3-ring PAHs. Culinary herbs, however, accumulated carcinogenic PAHs such as benzo[a]anthracene (highest concentration 11.9 µg/kg), benzo[b]fluoranthene (highest concentration 13.8 µg/kg) and chrysene (highest concentration 20.1 µg/kg) which might question their safe use.

A novel low sampling rate and cost-efficient active sampler for medium/long-term monitoring of gaseous pollutants

Active sampling is a dependable approach for gaseous pollutants monitoring, offering high accuracy and precision that is unaffected by environmental factors such as wind and temperature in comparison to passive sampling. To measure long-term average concentrations while minimizing the use of materials, a reduced sampling rate is necessary. Thus, this study aims to develop a novel low sampling rate (down to 1 mL/min) and cost-efficient active sampler (LASP) for medium/long-term monitoring of gaseous pollutants. The LASP mainly consisted of a syringe pump, a Y-shaped fitting with two one-way valves, and a control unit for intermittent operation. Results showed that LASP can obtain a sampling rate of less than 1 mL/min and sampling rate exhibited a high level of stability. Daily average concentrations measurements for nitrogen dioxide and formaldehyde by LASP had normalized mean biases of 2.8% and 5.2%, respectively. These numbers were - 5.8% and 6.1% for weekly-average samplings. This study demonstrated applications of LASP in real outdoor (daily-average) and indoor (weekly-average) air quality measurements. It worked well with low noise levels, and without interfering with occupants' daily activities. LASP can assist in improving our ability to monitor air quality and pollutants emissions, thereby supporting health research and policy development. ENVIRONMENTAL IMPLICATION: Gaseous air pollution is an important hazardous factor threatening human health. Medium/long-term air quality monitoring is essential for outdoor and indoor air quality assessment and control. However, air sampler for medium/long-term sampling is lacking. This study developed a novel low sampling rate and cost-efficient active sampler and applied it to medium/long-term air sampling. The sampler can work at a sampling rate of less than 1 mL/min. This technology provides a feasible strategy for medium/long-term monitoring of gaseous air pollutants in both environments and emission hotspots.

Disease burden and health risk to rural communities of northeastern India from indoor cooking-related exposure to parent, oxygenated and alkylated PAHs

Exposure to a total of 51 targeted and non-targeted polycyclic aromatic hydrocarbons (PAHs) and their oxygenated and alkylated derivatives associated with size-segregated aerosol was investigated in rural kitchens using liquefied petroleum gas (LPG), mixed biomass (MB) and firewood (FW) fuels in northeastern India. The averaged PM10-associated parent-, alkylated-, and oxygenated-PAHs concentrations increased notably from LPG (257, 54, and 116 ng m-3) to MB (838, 119, and 272 ng m-3) to FW-using kitchens (2762, 225, and 554 ng m-3), respectively. PAHs were preferentially associated with the PM1 fraction with contributions increasing from 80 % in LPG to 86 % in MB and 90 % in FW-using kitchens, which in turn was dominated by <0.25 μm particles (54-75 % of the total). A clear profile of enrichment of low-molecular weight PAHs in cleaner fuels (LPG) and a contrasting enrichment of high-molecular weight PAHs in biomass-based fuels was noted. The averaged internal dose of Benzo[a]pyrene equivalent was the lowest in the case of LPG (19 ng m-3), followed by MB (161 ng m-3) and the highest in FW users (782 ng m-3). Estimation of incremental lifetime cancer risk (ILCR) from PAH exposure revealed extremely high cancer risk in biomass users (factors of 8-40) compared to LPG. The potential years of life lost (PYLL) and PYLL rate averaged across kitchen categories was higher for lung cancer (PYLL: 10.55 ± 1.04 years; PYLL rate: 204 ± 426) compared to upper respiratory tract cancer (PYLL: 10.02 ± 0.05 years; PYLL rate: 4 ± 7), and the PYLL rates for biomass users were higher by factors of 9-56 as compared to LPG users. These findings stress the need for accelerated governmental intervention to ensure a quick transition from traditional biomass-based fuels to cleaner alternatives for the rural population of northeastern India.

Formation, migration, derivation, and generation mechanism of polycyclic aromatic hydrocarbons during frying

Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic and lipophilic, which can be found in frying system. This review summarized the formation, migration and derivation for PAHs, hypothesized the possible mechanism for PAHs generation during frying and presented the research prospects. Some factors like high oil consumption, high temperature, long time and oil rich in unsaturated fatty acids promoted the formation of PAHs and the presence of antioxidants inhibited the PAHs formation. The effect of proteins and carbohydrates in foods on the formation of PAHs is inconclusive. The formed PAHs were migrated into food and air. Moreover, some PAHs transformed into more toxic PAHs-derivatives during frying. The generation of PAHs may be related to low-barrier free radical-mediated reaction and the unsaturated hydrocarbons may be precursors of PAHs during frying. In future, the isotope tracer technology and on-line detection may be applied to discover intermediates and provide clues for studying PAHs generation mechanisms.

Understanding population exposure to size-segregated aerosol and associated trace elements during residential cooking in northeastern India: Implications for disease burden and health risk

Mass-size distribution of respirable aerosol and 13 associated trace elements (TEs) were investigated in rural kitchens using liquefied petroleum gas (LPG), firewood and mixed biomass fuels across three northeastern Indian states. The averaged PM10 (particulate matter with aerodynamic diameter ≤ 10 μm) and ΣTE concentrations were 403 and 30 μg m-3 for LPG, 2429 and 55 μg m-3 for firewood, and 1024 and 44 μg m-3 for mixed biomass-using kitchens. Mass-size distributions were tri-modal with peaks in the ultrafine (0.05-0.08 μm), accumulation (0.20-1.05 μm), and coarse (3.20-4.57 μm) modes. Respiratory deposition, estimated using the multiple path particle dosimetry model, ranged from 21 % to 58 % of the total concentration across fuel types and population age categories. Head, followed by pulmonary and tracheobronchial, was the most vulnerable deposition region, and children were the most susceptible age group. Inhalation risk assessment of TEs revealed significant non-carcinogenic as well as carcinogenic risk, especially for biomass fuel users. The potential years of life lost (PYLL) was the highest for chronic obstructive pulmonary disease (COPD: 15.9 ± 3.8 years) followed by lung cancer (10.3 ± 0.3 years) and pneumonia (10.1 ± 0.1 years), while the PYLL rate was also highest for COPD, with Cr(VI) being the major contributor. Overall, these findings reveal the significant health burden faced by the northeastern Indian population from indoor cooking using solid biomass fuels.

Findings of indoor air pollution and childhood obesity in a cross-sectional study of Chinese schoolchildren

BACKGROUND

Air pollution exposures are increasingly suspected to influence the development of childhood adiposity, especially focusing on outdoor exposure, but few studies investigated indoor exposure and childhood obesity.

OBJECTIVES

We aimed to examine the association between exposure to multiple indoor air pollutants and childhood obesity in Chinese schoolchildren.

METHODS

In 2019, we recruited 6499 children aged 6-12 years from five Chinese elementary schools in Guangzhou, China. We measured age-sex-specific body mass index z score (z-BMI), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR) on standard procedures. Four different indoor air pollution (IAP) exposures, including cooking oil fumes (COFs), home decoration, secondhand smoke (SHS), and incense burning, were collected by questionnaire and then converted into an IAP exposure index with four categories. Association between indoor air pollutants and childhood overweight/obesity as well as four obese anthropometric indices were assessed by logistic regression models and multivariable linear regression models, respectively.

RESULTS

Children exposed to ≥3 types of indoor air pollutants had higher z-BMI (coefficient [β]:0.142, 95% confidence interval [CI]:0.011-0.274) and higher risk of overweight/obesity (odd ratio [OR]:1.27, 95%CI:1.01-1.60). And a dose-response relationship was discovered between the IAP exposure index and z-BMI as well as overweight/obesity (p_{for trend}<0.05). We also found that exposure to SHS and COFs was positively associated with z-BMI and overweight/obesity (p < 0.05). Moreover, there was a significant interaction between SHS exposure and COFs on the higher risk of overweight/obesity among schoolchildren. Boys appear more susceptible to multiple indoor air pollutants than girls.

CONCLUSIONS

Indoor air pollution exposures were positively associated with higher obese anthropometric indices and increased odds of overweight/obesity in Chinese schoolchildren. More well-designed cohort studies are needed to verify our results.

Pot study using Chlorophytum comosum plants to biomonitor PAH levels in domestic kitchens

In indoor environments, cooking is a major contributor to indoor air pollution releasing potentially harmful toxic compounds such as polycyclic aromatic hydrocarbons. In our study, Chlorophytum comosum 'Variegata' plants were applied to monitor PAH emission rates and patterns in previously selected rural Hungarian kitchens. Concentration and profile of accumulated PAHs could be well explained by cooking methods and materials used in each kitchen. Accumulation of 6-ring PAHs was characteristic in the only kitchen which frequently used deep frying. It also should be emphasized that applicability of C. comosum as indoor biomonitor was assessed. The plant has proven a good monitor organism as it accumulated both LMW and HMW PAHs.

Characteristics of PM2.5 emissions from six types of commercial cooking in Chinese cities and their health effects

Commercial kitchens may pose significant health risks to workers because they generate large quantities of fine particulate matter (PM_2.5). In our study, the concentrations and emission rates of PM_2.5 in cooking environments were measured for six types of commercial kitchens that used electricity and natural gas (including traditional Chinese kitchens, western kitchens, teppanyaki kitchens, fried chicken kitchens, barbecue kitchens, and hotpot cooking area). Furthermore, a preliminary health risk assessment of the chefs was undertaken using the annual PM_2.5 inhalation and PM_2.5 deposition rates into the upper airways and tracheobronchial and alveolar regions of the human body. Results showed that cooking in the teppanyaki kitchen generated the highest amount of PM_2.5, with a mean emission rate of 7.7 mg/min and a mean mass concentration of 850.4 ± 533.4 μg/m³ in the breathing zone. Therefore, teppanyaki kitchens pose highest PM_2.5 exposure risks to chefs, with the highest rate of PM_2.5 deposition in the upper airways (6.38 × 10⁵ μg/year), followed by Chinese kitchens. The PM_2.5 concentrations and emission rates of each kitchen varied greatly with the dishes cooked. The mean PM_2.5 concentration was the highest during Chinese stir-frying, with the peak concentration reaching more than 20,000 μg/m³, followed by pan-frying, deep-frying, stewing, and boiling. A rise in PM_2.5 concentration was also observed during the start of stir-frying and in the middle to late stages of pan-frying and grilling meat. The results obtained in our study may contribute in understanding the characteristics of PM_2.5 emissions from various types of commercial kitchens and their health effects.

Polycyclic aromatic hydrocarbons in breast milk of nursing mothers: Correlates with household fuel and cooking methods used in Uganda, East Africa

Maternal breast milk, which is a complete food for the infant's growth, development, and health, contains fats and lipids making it susceptible to accumulation of lipophilic compounds like polycyclic aromatic hydrocarbons (PAHs). This study aimed at analyzing correlates of measured levels of PAHs in breast milk of nursing mothers to frequently used household fuels and cooking methods in Uganda, and estimate the potential health risks of PAHs to infants through breastfeeding. Sixty breast milk samples were collected from healthy and non-smoking mothers who had lived in Kampala capital city (urban area) and Nakaseke district (rural area) for at least five years. Sample extracts were analyzed for PAHs using a gas chromatograph coupled with a triple quadrupole mass spectrometer. ∑₁₃PAHs in samples from Kampala ranged from 3.44 to 696 ng/g lw while those from Nakaseke ranged from 0.84 to 87.9 ng/g lw. PAHs with 2-3 rings were more abundant in the samples than PAHs with 4-6 rings. At least 33 % of the variance in the levels of ∑₁₃PAHs in the breast milk samples was attributable to the fuel type and cooking methods used. Nursing mothers who used charcoal for cooking accumulated higher levels of ∑₁₃PAHs in their breast milk samples compared to those who used firewood. Levels of ∑₁₃PAHs in breast milk of mothers increased depending on the cooking methods used in the order; boiling< grilling< deep-frying. In all samples, hazard quotients for PAHs were <1 and estimated incremental cancer risks were all between 10^-6 and 10^-4, indicating that the health risks to infants due to the ingestion of PAHs in breast milk was tolerable. Further studies with large datasets on PAHs and their derivatives and, larger samples sizes are needed to confirm these findings.

Ranking the environmental factors of indoor air quality of metropolitan independent coffee shops by Random Forests model

Independent coffee shops are the alternative workplaces for people working remotely from traditional offices but are not concerned about their indoor air quality (IAQ). This study aimed to rank the environmental factors in affecting the IAQ by Random Forests (RFs) models. The indoor environments and human activities of participated independent coffee shops were observed and recorded for 3 consecutive days including weekdays and weekend during the business hours. The multi-sized particulate matter (PM), particle-bound polycyclic aromatic hydrocarbons (p-PAHs), total volatile organic compounds (TVOCs), CO, CO₂, temperature and relative humidity were monitored. RFs models ranked the environmental factors. More than 20% of the 15-min average concentrations of PM₁₀, PM_2.5, and CO₂ exceeded the World Health Organization guidelines. Occupant density affected TVOCs, p-PAHs and CO₂ concentrations directly. Tobacco smoking dominated PM₁₀, PM_2.5, TVOCs and p-PAHs concentrations mostly. CO concentration was affected by roasting bean first and tobacco smoking secondly. The non-linear relationships between temperature and these pollutants illustrated the relative low concentrations happened at temperature between 22 and 24 °C. Tobacco smoking, roasting beans and occupant density are the observable activities to alert the IAQ change. Decreasing CO₂ and optimizing the room temperature could also be the surrogate parameters to assure the IAQ.

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.

Valproic acid counteracts polycyclic aromatic hydrocarbons (PAHs)-induced tumorigenic effects by regulating the polarization of macrophages

Polycyclic aromatic hydrocarbons (PAHs) are common persistent organic pollutants that are carcinogenic, teratogenic and mutagenic, causing a variety of harm to human health. In this study, we investigated the mechanism of how valproic acid (VPA) interferes with the carcinogenesis of PAHs protect normal tissues via the regulation of macrophages' function. Using the established model of transformed malignant breast cancer by 7,12-dimethylbenz[a]anthracene (DMBA), a representative PAH carcinogen, we discovered VPA induces the polarization of macrophages toward the M1 phenotype in the tumor tissues, facilitates the expression of pro-inflammatory cytokines such as IFN-γ, IL-12 and TNF-α, activates CD8⁺ T cells to secret Granzyme B thus to promote the apoptosis of tumor cells and suppresses the viability of vascular endothelial cells in tissue stroma of tumor. Surprisingly, VPA selectively induces macrophages to polarize towards the M2 phenotype in normal tissues and promotes the expression of anti-inflammatory cytokines such as IL-10 to enhance cell proliferation. Additionally, at the cellular level, VPA can directly regulate the polarization of macrophages to affect the growth of vascular endothelial cells by simulating the living conditions of tumor and normal cells. Collectively, VPA exerts an interventional effect on tumor growth and a protective effect on normal tissues by regulation of selective macrophages' polarization in their microenvironment.

Chemical profiles of PM2.5 emitted from various anthropogenic sources of the Eastern Mediterranean: Cooking, wood burning, and diesel generators

The chemical profiles of PM_2.5 emitted from a non-road diesel generator, wood burning and cooking activities including chicken and beef charcoal grilling and general cooking activities were determined. The characterization included the carbonaceous fraction (OC/EC), water-soluble ions, elements, and organic species comprising n-alkanes, polycyclic aromatic hydrocarbons, carboxylic acids, levoglucosan, dioxins, furans, and dioxin-like polychlorinated biphenyls. The main component in the PM_2.5 from the different sources was carbonaceous matter with a mass contribution to PM_2.5 of 49% for cooking activities, 53% for wood burning, 66% for beef grilling, 72% for chicken grilling, and 74% for diesel generator with different OC/EC concentration ratios. The analysis of organic compounds contents using diagnostic ratios and indexes showed differences between the sources and revealed specific source markers. The water-soluble ions had the highest contribution in the cooking activities profile with 17% of PM_2.5 and the least in the chicken grilling profile (1.1%). Additionally, 29 analyzed elements were identified, and their contribution varied with the sources (ranging from 1% to 11% of PM_2.5). These findings could be used to differentiate these sources and could assist in the use of source apportionment methods.

Investigation on the Direct Transfer of SVOCs from Source to Settled Dust: Analytical Model and Key Parameter Determination

Settled dust is an important medium for semivolatile organic compound (SVOC) transport indoors. Understanding the mechanism of interaction between SVOCs and settled dust can greatly improve the exposure assessment. This study develops an analytical model to elucidate the mechanism of direct contact between SVOC sources and settled dust. The model incorporates the adsorption of SVOCs onto indoor surfaces, which was ignored in previous numerical models. Based on this model, a hybrid optimization method is applied to determine the key parameters of SVOC transport, i.e., the diffusion coefficient in the dust, the dust-air partition coefficient, and the chamber surface-air partition coefficient. Experiments of direct contact between SVOC source materials containing organophosphorus flame retardants (OPFRs) and settled dust were conducted in chambers. The key parameters were determined by performing curve fitting using data collected from the OPFR chamber tests and from the literature on phthalates. The reliability and robustness of the model and measurement method are demonstrated by the high fitting accuracy and sensitivity analysis. The obtained key parameters are more accurate than those from correlations in prior studies. Further analysis indicates that dust-air partition coefficient plays an important role and the adsorption effect on surfaces cannot be neglected for SVOC transport.

Polycyclic aromatic hydrocarbons from cooking emissions

Air pollution studies have often overlooked the contribution from cooking to the particle-bound polycyclic aromatic hydrocarbons (PAHs) in the ambient environment, despite cooking emissions have been identified as an important source of organic aerosol in most urban areas, known as the cooking-like organic aerosol factor (i.e., COA). In this study, a Long-Time-of-Flight (LToF) soot particle aerosol mass spectrometer (SP-AMS) was deployed to evaluate the impact of cooking emissions on outdoor particle-bound PAHs levels during a summer campaign in 2019 in Xi'an China. Combined with the robust receptor model, cooking emission was found to be the major source of ambient PAHs, on average, accounting for 90% of PAHs, 9 times higher than traffic (10%). The ambient cooking PAH profile was well correlated (r² of 0.87) with that for frying oil fume, suggesting cooking oil was the major source of PAHs instead of the food being cooked. We further evaluated the health risk associated with the cooking PAHs and estimated the cooking PAH levels in some of the major cities in the world where COA factor has been reported. The results show the particle-bound PAHs from cooking can be an important source of ambient PAHs in most Chinese cities. The findings from this study hold important implications for public health and are informing for policymakers.

Characteristics, Source Contributions, and Source-Specific Health Risks of PM2.5-Bound Polycyclic Aromatic Hydrocarbons for Senior Citizens during the Heating Season in Tianjin, China

Polycyclic aromatic hydrocarbons (PAHs) have carcinogenic impacts on human health. However, limited studies are available on the characteristics, sources, and source-specific health risks of PM2.5-bound PAHs based on personal exposure data, and comparisons of the contributions of indoor and outdoor sources are also lacking. We recruited 101 senior citizens in the winter of 2011 for personal PM2.5 sample collection. Fourteen PAHs were analyzed, potential sources were apportioned using positive matrix factorization (PMF), and inhalational carcinogenic risks of each source were estimated. Six emission sources were identified, including coal combustion, gasoline emission, diesel emission, biomass burning, cooking, and environmental tobacco smoking (ETS). The contribution to carcinogenic risk of each source occurred in the following sequence: biomass burning > diesel emission > gasoline emission > ETS > coal combustion > cooking. Moreover, the contributions of biomass burning, diesel emission, ETS, and indoor sources (sum of cooking and ETS) to PAH-induced carcinogenic risk were higher than those to the PAH mass concentration, suggesting severe carcinogenic risk per unit contribution. This study revealed the contribution of indoor and outdoor sources to mass concentration and carcinogenic risk of PM2.5-bound PAHs, which could act as a guide to mitigate the exposure level and risk of PM2.5-bound PAHs.

An insight on microbial degradation of benzo[a]pyrene: current status and advances in research

Benzo[a]pyrene (BaP) is a high molecular weight polycyclic aromatic hydrocarbon produced as a result of incomplete combustion of organic substances. Over the years, the release of BaP in the atmosphere has increased rapidly, risking human lives. BaP can form bonds with DNA leading to the formation of DNA adducts thereby causing cancer. Therefore addressing the problem of its removal from the environment is quite pertinent though it calls for a very cumbersome and tedious process owing to its recalcitrant nature. To resolve such issues many efforts have been made to develop physical and chemical technologies of BaP degradation which have neither been cost-effective nor eco-friendly. Microbial degradation of BaP, on the other hand, has gained much attention due to added advantage of the high level of microbial diversity enabling great potential to degrade the substance without impairing environmental sustainability. Microorganisms produce enzymes like oxygenases, hydrolases and cytochrome P450 that enable BaP degradation. However, microbial degradation of BaP is restricted due to several factors related to its bio-availability and soil properties. Technologies like bio-augmentation and bio-stimulation have served to enhance the degradation rate of BaP. Besides, advanced technologies such as omics and nano-technology have opened new doors for a better future of microbial degradation of BaP and related compounds.

Effects of architecture structure on volatile organic compound and polycyclic aromatic hydrocarbon diffusion in Singapore's Integrated Transport Hubs

Millions of passengers wait for buses at Integrated Transport Hubs (ITH) daily in metropolitan cities. Environmental exposure and associated risk for passengers is of great public concern. In this study, eight volatile organic compounds (VOCs) and the 16 EPA priority polycyclic aromatic hydrocarbons (PAHs) were analyzed in airborne samples collected from indoor waiting areas (Indoor) and bus parks of nine Singapore ITH, which comprises of two types of architectural structure (i.e., fully sheltered and open/partially enclosed). The median concentrations of total VOCs (TVOCs), total gaseous PAHs (TgPAHs) and total airborne particles-adsorbed PAH (TpPAHs) concentrations in Indoor were 30.42 μg/m³, 18.99 ng/m³ and 1.38 ng/m³; respectively. A strong correlation (r ≥ 0.75, p < 0.001) was observed between Indoor and bus parks air compounds. The "Indoor" to bus park pollutant concentration ratio (I/B ratio) showed lower values in the bus interchanges with fully sheltered bus parks (TVOCs: 0.98; TgPAHs: 0.76; TpPAHs: 0.71) than those with open/partially enclosed ones (TVOCs: 1.28; TgPAHs: 1.31; TpPAHs: 0.90). This result suggests that fully sheltered structure may cause the accumulation of air pollutants. The daily VOC and PAH exposure for commuters were further estimated by considering inhalation and dermal doses using Monte Carlo simulation (n = 100,000). Overall, the result showed that the risk is still within international guideline values. In sum, the effect of architecture structure on the migration of air pollutants should be taken into consideration in future transport hub design to reduce pollutant exposure to commuters.

Hazard Levels of Cooking Fumes in Korea schools

Background and Purpose

In 2021, lung cancer in school food workers was first recognized as an occupational cancer. The classification of the carcinogenicity of cooking fumes by International Agency for Research on Cancer (IARC) was based on Chinese epidemiological data. This study aimed to determine the hazard levels of school cooking fumes in Korea.

Materials and Methods

Based on public school cafeterias in one area, 25 locations were selected for the survey according to the number per school type, ventilation states, and environmental pre-assessments of cafeterias. Two inside cooking areas using a heat source and one outside cooking area were selected as control measurement points. Measurements of CO, CO₂, polycyclic aromatic hydrocarbons (PAHs), and total volatile organic compounds (TVOCs), including benzene, formaldehyde, and particulate matter (PM10, PM2.5, PM1, respectively), were taken. The concentrations and patterns of each substance in the kitchens were compared with the outdoor air quality.

Result

Known carcinogens, such as the concentrations of PAHs, formaldehyde, TVOC (benzene), and particulate matter in school cooking fumes, were all detected at similar or slightly higher levels than those found outside. Additionally, substances were detected at relatively low concentrations compared to the Chinese cooking fumes reported in the literature. However, the short-term exposure to high concentrations of CO (or composite exposure with CO₂) and PM2.5 in this study were shown.

Conclusion

The school cooking fumes in South Korea was a relatively less harmful than Chinese cooking fumes, however short-term, high exposure of toxic substances can cause a critical health effect.

The chemical composition and toxicological effects of fine particulate matter (PM2.5) emitted from different cooking styles

The mass, chemical composition and toxicological properties of fine particulates (PM_2.5) emitted from cooking activities in three Hong Kong based restaurants and two simulated cooking experiments were characterized. Extracts from the PM_2.5 samples elicited significant biological activities [cell viability, generation of reactive oxygen species (ROS), DNA damage and inflammation effect (TNF-α)] in a dose-dependent manner. The composition of PAHs, oxygenated PAHs (OPAHs) and azaarenes (AZAs) mixtures differed between samples. The concentration ranges of the Σ30PAHs, Σ17OPAHs and Σ4AZAs and Σ7Carbonyls in the samples were 9627-23,452 pg m^-3, 503-3700 pg m^-3, 33-263 pg m^-3 and 158 - 5328 ng m^-3, respectively. Cell viability caused by extracts from the samples was positively correlated to the concentration of benzo[a]anthracene, indeno[1,2,3-cd]pyrene and 1,4-naphthoquinone in the PM_2.5 extracts. Cellular ROS production (upon exposure to extracts) was positively correlated with the concentrations of PM_2.5, decaldehyde, acridine, Σ17OPAHs and 7 individual OPAHs. TNF-α showed significant positive correlations with the concentrations of most chemical species (elemental carbon, 16 individual PAHs including benzo[a]pyrene, Σ30PAHs, SO₄^2-, Ca²⁺, Ca, Na, K, Ti, Cr, Mn, Fe, Cu and Zn). The concentrations of Al, Ti, Mn, Σ30PAHs and 8 individual PAHs including benzo[a]pyrene in the samples were positively correlated with DNA damage caused by extracts from the samples. This study demonstrates that inhalation of PM_2.5 emitted from cooking could result in adverse human health effects.

Indoor Particulate Matter in Urban Households: Sources, Pathways, Characteristics, Health Effects, and Exposure Mitigation

Particulate matter (PM) is a complex mixture of solid particles and liquid droplets suspended in the air with varying size, shape, and chemical composition which intensifies significant concern due to severe health effects. Based on the well-established human health effects of outdoor PM, health-based standards for outdoor air have been promoted (e.g., the National Ambient Air Quality Standards formulated by the U.S.). Due to the exchange of indoor and outdoor air, the chemical composition of indoor particulate matter is related to the sources and components of outdoor PM. However, PM in the indoor environment has the potential to exceed outdoor PM levels. Indoor PM includes particles of outdoor origin that drift indoors and particles that originate from indoor activities, which include cooking, fireplaces, smoking, fuel combustion for heating, human activities, and burning incense. Indoor PM can be enriched with inorganic and organic contaminants, including toxic heavy metals and carcinogenic volatile organic compounds. As a potential health hazard, indoor exposure to PM has received increased attention in recent years because people spend most of their time indoors. In addition, as the quantity, quality, and scope of the research have expanded, it is necessary to conduct a systematic review of indoor PM. This review discusses the sources, pathways, characteristics, health effects, and exposure mitigation of indoor PM. Practical solutions and steps to reduce exposure to indoor PM are also discussed.

Fingerprinting and emission rates of particulate organic compounds from typical restaurants in Portugal

The aim of this study was a detailed chemical characterisation of the particles released during the preparation of popular Portuguese dishes. PM_2.5 samples were collected from the exhaust stacks on the roofs of a university canteen, a charcoal-grilled chicken restaurant and a wood-oven roasted piglet restaurant. The speciation of organic compounds was carried out by gas chromatography-mass spectrometry. The canteen was responsible for the lowest emissions of PM_2.5, while emissions from the roasted piglet restaurant were the highest. Naphthalene was quantified as the most abundant aromatic compound in particle emissions from the canteen, while phenanthrene, fluoranthene, pyrene and chrysene were the dominant polycyclic aromatic hydrocarbons in samples from the other establishments. Benzo[a]pyrene equivalent concentrations obtained for the charcoal-grilled chicken and piglet restaurant indicate a dangerous carcinogenic potential to human health. Cholesterol was the prevalent sterol. Its highest values were obtained in particles from the charcoal-grilled chicken restaurant (621 ± 233 μg g^-1 PM_2.5). Oleic and palmitoleic were the unsaturated fatty acids identified at highest concentrations (from trace levels to 34.4 and to 6.89 mg g^-1 PM_2.5, respectively). Resin acids, such as dehydroabietic and abietic, were detected in all samples from the wood-oven roasted piglet restaurant. Nicotinamide was the amide detected at highest amount in emissions from the university canteen during the preparation of stews (7.67 mg g^-1 PM_2.5). Levoglucosan and its isomers were identified in all samples from the roasted piglet restaurant, but only the first monosaccharide anhydride was present in emissions from the university canteen and the charcoal-grilled chicken restaurant. Additionally, emission rates were estimated for the most representative compounds, taking into account the specific activity of each restaurant.

A review of human and animals exposure to polycyclic aromatic hydrocarbons: Health risk and adverse effects, photo-induced toxicity and regulating effect of microplastics

Polycyclic aromatic hydrocarbons (PAHs) are one of the most widely distributed persistent organic pollutants (POPs) in the environmental media. PAHs have been widely concerned due to their significant health risk and adverse effects to human and animals. Currently, the main sources of PAHs in the environment are the incomplete combustion of fossil fuels, as well as municipal waste incineration and agricultural non-surface source emissions. In this work, the scope of our attention includes 16 typical PAHs themselves without involving their metabolites and industrial by-products. Exposure of human and animals to PAHs can lead to a variety of adverse effects, including carcinogenicity and teratogenicity, genotoxicity, reproductive- and endocrine-disrupting effects, immunotoxicity and neurotoxicity, the type and severity of which depend on a variety of factors. On the other hand, the regulatory effect of microplastics (MPs) on the bio-toxicity and bioaccumulation capacity of PAHs has now gradually attracted attention. We critically reviewed the adsorption capacity and mechanisms of MPs on PAHs as well as the effects of MPs on PAHs toxicity, thus highlighting the importance of paying attention to the joint bio-toxicity caused by PAHs-MPs interactions. In addition, due to the extensive nature of the common exposure pathway of PAHs and ultraviolet ray, an accurate understanding of biological processes exposed to both PAHs and UV light is necessary to develop effective protective strategies. Finally, based on the above critical review, we highlighted the research gaps and pointed out the priority of further studies.

Cooking activities in a domestic kitchen: Chemical and toxicological profiling of emissions

To obtain emission factors and cooking-related chemical signatures, a monitoring campaign was carried out in a modern kitchen where different dishes of the Latin cuisine were prepared. Particulate matter (PM₁₀, PM_2.5 and PM₁) and total volatile organic compounds (TVOCs) were continuously measured. Passive tubes for carbonyls and a high volume PM₁₀ sampler were simultaneously used. PM₁₀ filters were analysed for organic and elemental carbon and for multiple organic compounds, including polyaromatic hydrocarbons (PAHs). The toxic potential of PM₁₀ was evaluated using a bioluminescence inhibition bioassay. Acrolein was never detected, while formaldehyde and acetaldehyde levels were comparable to those in the background air. The protection limit for TVOCs was always exceeded. Fine particles comprised more than 86% of the PM₁₀ mass concentrations. PM₁₀ emission rates ranged from 124 to 369 μg min^-1. Relatively low PAH concentrations were obtained. PM₁₀ encompassed alcohols, acids, plasticisers, alkyl esters, sterols, sugars, polyols, glyceridic compounds, phenolics, among others. Total concentrations were 1.9-5.3 times higher during cooking than in the background air but, for some compounds, differences of tens or hundreds of times were registered. PM₁₀ from grilled pork was found to contribute to non-negligible cancer risks and to be very toxic, while samples from other dishes were categorised as toxic.

Impact of different cooking methods on polycyclic aromatic hydrocarbons in rabbit meat

The influence of a variety of cooking methods (poaching, boiling, grilling (charcoal or gas)), frying (pan, deep frying, and stir frying) with a variety of oils (vegetable oil, extra virgin olive oil, sesame oil, extra light olive oil, and sunflower oil), microwaving, and oven roasting on polycyclic aromatic hydrocarbons (PAHs) formation in rabbit meat samples was investigated. Meat samples (including three replicates) were prepared without additives or spices. PAHs extraction was carried out by saponification method with potassium hydroxide in methanol which was followed by a silica gel column technique and the samples were quantified by using gas chromatography with mass spectrometry (GC-MS). PAHs standards, fluorene, naphthalene, anthracene, phenanthrene, pyrene, acenaphthalene, fluoranthene, and benzopyrene, were used for this study. The other PAHs except fluorene were not observed (detection limit-0.009 µg/g) in all the samples. Among traditional processing techniques, higher PAH contents were observed as a result of frying. Frying with vegetable oil produced higher fluorene content (0.06-0.13 µg/g) in the deep-fried sample, although sesame oil is the best oil which produces lowest PAH contents in fried samples. Among all the processing techniques, lower fluorene (0.01-0.02 µg/g) content was noticed in poaching. Benzo(a)pyrene was not observed in all the investigated samples which is viewed as a reliable strategy of the cooking process for human consumption. After processing, the cooking loss was determined and oven roasting and grilling exhibited greater moisture loss.

Polycyclic aromatic hydrocarbons residues and the carcinogenic risk assessment to pregnant women in Nantong, China using QuEChERS method and HPLC-A pilot case study

A high-performance liquid chromatographic method with a modified QuEChERS extraction for the determination of polycyclic aromatic hydrocarbons (PAHs) in blood serum was developed to investigate the internal exposure level and the carcinogentic toxicity contribution rate of PAHs for pregnant women in Nantong, China. Venous blood (n = 48) was collected in the local hospital and the internal exposure level of 16 PAHs and the contribution rate of carcinogenicity to pregnant women were analyzed. Among all of the detected PAHs, the detection rate of pyrene (77.08%) was the highest, followed by naphthalene (64.58%) and benzo[a]anthracene (BaA, 45.83%). The carcinogenicity contribution rate of BaA (37.37%) was the highest, followed by fluorene (32.96%) and acenaphthylene (22.01%). The results showed that many kinds of carcinogenic PAHs can be detected in the serum of pregnant women in Nantong city, among which BaA should be paid most attention because of its high internal exposure level and carcinogenic risk. Meanwhile, the origins of general PAHs in serum samples were analyzed using the characteristic ratio analysis method. The PAH pollution level of air samples (n = 42) during the collection time of blood samples was also analyzed to compare the possible correlations between the two different results.

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.

Cytotoxicity and Potential Pathway to Vascular Smooth Muscle Cells Induced by PM2.5 Emitted from Raw Coal Chunks and Clean Coal Combustion

Coal combustion emits a large amount of PM_2.5 (particulate matters with aerodynamic diameters less than 2.5 μm) and causes adverse damages to the cardiovascular system. In this study, emissions from anthracite and bitumite were examined. Red mud (RM) acts as an additive and is mixed in coal briquettes with a content of 0-10% as a single variable to demonstrate the reduction in the PM_2.5 emissions. Burnt in a regulated combustion chamber, the 10% RM-containing bitumite and anthracite briquettes showed 52.3 and 18.6% reduction in PM_2.5, respectively, compared with their chunk coals. Lower cytotoxicity (in terms of oxidative stresses and inflammation factors) was observed for PM_2.5 emitted from the RM-containing briquettes than those from non-RM briquettes, especially for the bitumite groups. Besides, the results of western blotting illustrated that the inhibition of NF-κB and MAPK was the potential pathway for the reduction of cytokine levels by the RM addition. The regression analyses further demonstrated that the reduction was attributed to the lower emissions of transition metals (i.e., Mn) and PAHs (i.e., acenaphthene). This pilot study provides solid evidence for the cytotoxicity to vascular smooth muscle cells induced by PM_2.5 from coal combustion and potential solutions for reducing the emission of toxic pollutants from human health perspectives.

Quantification of polycyclic aromatic hydrocarbons in kitchen depositions by SUPRAS-LC-FLR and human health risk assessment

Concentration, composition and sources of polycyclic aromatic hydrocarbons (PAHs) in kitchen depositions from different sampling categories such as restaurants, university mess and houses were investigated, and associated human exposure risk through dietary intake, inhalation and dermal contact was determined. The PAHs in the samples were extracted by supramolecular solvent based microextraction (SUPRAS) method and the concentrations were determined by high pressure liquid chromatography (HPLC) with fluorescence detection. The mean of Σ16PAHs concentration was found to be the highest (386.09 ± 413.17 mg kg^-1) for restaurants followed by mess (80.91 ± 92.81 mg kg^-1) and houses (24.65 ± 10.52 mg kg^-1). Traffic sources were found to be predominant contributors of PAHs in restaurants while cooking activities were the sources for mess and houses. Three- and five-ring PAHs were prominent in restaurants and mess samples while two- and three-ring PAHs contributed the most in houses samples. Non-cancer risk (hazard index) from exposure to these PAHs was found to be within safe limits i.e. 2.70E-09 to 7.46E-08. Estimated lifetime cancer risk was found to range from 2.46E-06 to 7.81E-04 from exposure to these PAHs and indicates significant risk due to exceeding the guideline value of 10^-6.

Classroom Dust-Bound Polycyclic Aromatic Hydrocarbons in Jeddah Primary Schools, Saudi Arabia: Level, Characteristics and Health Risk Assessment

Data concerning polycyclic aromatic hydrocarbons (PAHs) in Jeddah's schools, Saudi Arabia, and their implications for health risks to children, is scarce. Classroom air conditioner filter dusts were collected from primary schools in urban, suburban and residential areas of Jeddah. This study aimed to assess the characteristics of classroom-dust-bound PAHs and the health risks to children of PAH exposure. Average PAH concentrations were higher in urban schools than suburban and residential schools. Benzo (b)fluoranthene (BbF), benzo(ghi)perylene (BGP), chrysene (CRY) and Dibenz[a,h]anthracene (DBA) at urban and suburban schools and BbF, BGP, fluoranthene (FLT) and indeno (1, 2, 3, -cd)pyrene (IND) at residential schools were the dominant compounds in classroom dust. PAHs with five aromatic rings were the most abundant at all schools. The relative contribution of the individual PAH compounds to total PAH concentrations in the classroom dusts of schools indicate that the study areas do share a common source, vehicle emissions. Based on diagnostic ratios of PAHs, they are emitted from local pyrogenic sources, and traffic is the significant PAH source, with more significant contributions from gasoline-fueled than from diesel cars. Based on benzo[a]pyrene equivalent (BaPequi) calculations, total carcinogenic activity (TCA) for total PAHs represent 21.59% (urban schools), 20.99% (suburban schools), and 18.88% (residential schools) of total PAH concentrations. DBA and BaP were the most dominant compounds contributing to the TCA, suggesting the importance of BaP and DBA as surrogate compounds for PAHs in this schools. Based on incremental lifetime cancer risk (ILCingestion, ILCRinhalation, ILCRdermal) and total lifetime cancer risk (TLCR)) calculations, the order of cancer risk was: urban schools > suburban schools > residential schools. Both ingestion and dermal contact are major contributors to cancer risk. Among PAHs, DBA, BaP, BbF, benzo(a)anthracene (BaA), benzo(k)fluoranthene (BkF), and IND have the highest ILCR values at all schools. LCR and TLCR values at all schools were lower than 10-6, indicating virtual safety. DBA, BaP and BbF were the predominant contributors to cancer effects in all schools.

Evaluation of the effectiveness of a portable air cleaner in mitigating indoor human exposure to cooking-derived airborne particles

Gas cooking is an important source of airborne particulate matter (PM) indoors. Exposure to cooking-derived PM can lead to adverse human health impacts on non-smokers, especially in poorly-ventilated residential homes. Most of the previous studies on gas cooking emissions mainly focused on fine particles (PM_2.5) with little information on their size-fractionation. Moreover, studies dealing with mitigation of indoor human exposure to cooking-derived PM are currently sparse. Therefore, a systematic study was conducted to investigate the characteristics of PM_2.5 and size-fractionated PM derived from five commonly used cooking methods, namely, steaming, boiling, stir-frying, pan-frying and deep-frying in a poorly-ventilated domestic kitchen under controlled experimental conditions. Additionally, an indoor portable air cleaner was employed as a mitigation device to capture cooking-derived PM and improve indoor air quality (IAQ). Results revealed that the oil-based deep-frying cooking released the highest airborne particles which were about 170 folds higher compared to the baseline levels for PM_2.5 mass concentrations. The use of the air cleaner showed a statistically significant (p < 0.05) reduction in the indoor PM_2.5 levels. Moreover, PM_<0.25 (particles with diameter ≤ 250 nm) showed a very high mass concentration (378.2 μg/m³) during deep-frying, raising human health concern. A substantial reduction (~60-85%) in PM_<0.25 mass concentrations and their total respiratory deposition doses (RDD) in the human respiratory tract was observed while using the air cleaner during the five cooking methods. Furthermore, morphological characteristics and the relative abundance of trace elements in cooking-derived PM were also investigated. This study provides useful insights into the assessment and mitigation of indoor human exposure to cooking-derived PM.

Risk Assessment and Implications of Schoolchildren Exposure to Classroom Heavy Metals Particles in Jeddah, Saudi Arabia

Classrooms Air Conditioner Filter (CACF) particles represent all of the exposed particles that have migrated to the interior environment. This study was conducted to assess the heavy metals contamination in CACF particles from Jeddah primary schools located in urban, suburban and residential areas; and to evaluate their health risks of children exposure (non-carcinogenic and carcinogenic). Heavy metals levels in CACF particles of schools were in the following order: urban schools > suburban schools > residential schools. Fe, Mn and Zn were the dominant species. Geo-accumulation index (I_geo), contamination factor (CF) and pollution load index (PLI) values indicated that the contamination levels was in the following order Cd > Pb > Zn > As > Cu > Ni > Mn > Cr > Co >V > Fe. School CACF particles was moderately contaminated with As and Zn and moderately to heavily contaminated with Pb and Cd. Enrichment factors (EFs) indicated that Zn, Cd, Pb, As and Cu in CACF particles were severe enriched. The hazard quotient (HQs) and hazards index (HI) values for heavy metals were lower than the acceptable level of one. As, Pb, Cr and Mn were exhibited high non-cancer effects for children. The lifetime cancer risk (LCR) and total lifetime cancer risk (TLCR), HQs and HI values for the different exposure pathways of heavy metals decreased in the following order: ingestion > dermal contact > inhalation. Carcinogenic and non-carcinogenic risk rank order of schools were urban schools > suburban schools > residential schools. The LCR and TLCR of heavy metals was in the following order: Co > Ni >Cr > Cd > As > Pb. The ingestion lifetime cancer risk (LCR_ing) and TLCR values from exposure to Ni and Cr in urban and suburban schools, Cd in urban schools, and Co in all Jeddah schools only exceed the acceptable range (1 × 10⁻⁶–1 × 10⁻⁴) Only LCR_ing and TLCR values from exposure to ∑ carcinogens exceed the acceptable level.

Characterization of polycyclic aromatic hydrocarbon (PAHs) source profiles in urban PM2.5 fugitive dust: A large-scale study for 20 Chinese cites

Polycyclic aromatic hydrocarbons (PAHs) in road dust (RD) and construction dust (CD) in PM_2.5 were quantified in the samples collected in 20 Chinese cities. The PAHs profiles in urban PM_2.5 fugitive dusts were determined and their potential health risks were evaluated. Seven geographical regions in China were identified as northwest China (NWC), the North China Plain (NCP), northeast China (NEC), central China (CC), south China (SC), southwest China (SWC), and east China (EC). The overall average concentrations of total quantified PAHs (ΣPAHs) were 23.2 ± 18.9 and 22.8 ± 29.6 μg·g^-1 in RD and CD of PM_2.5, indicating that severe PAHs pollution to urban fugitive dusts in China. The differences of ΣPAHs between RD and CD were minor in northern and central regions of China but much larger in southern and east regions. The ƩPAHs for RD displayed a pattern of "high in northern and low in southern", and characterized by large abundance of high molecular weights (HMWs) PAHs, indicating that vehicle emission was the predominant pollution origin. Additionally, higher diagnostic ratios of fluoranthene/(fluoranthene + pyrene) in NCP, CC, and SWC suggest critical contributions of biomass burning and coal combustion for RD in these areas. In comparison, gasoline combustion was the major pollution source for CD PAHs in NWC, NCP, NEC, and CC, whereas industrial emissions such as cement production and iron smelting had strong impacts in the heavy industrial regions. The total benzo[a]pyrene (BaP) carcinogenic potency concentrations (BaP_TEQ) for RD and CD both showed the lowest in SC (0.05 and 0.07, respectively) and the highest in NCP (10.99 and 7.67, respectively). The highest and lowest incremental life cancer risks (ILCR) were found in NCP and SC, coinciding with the spatial distributions of ambient PAHs levels. The total CD-related cancer risks for adults and children (~10^-4) suggest high potential health risks in NCP, SWC, and NWC, whereas the evaluated values in EC and SC indicate virtual safety (≤10^-6).

PAHs contamination levels in the breast milk of Ghanaian women from an e-waste recycling site and a residential area

Breast milk samples from 128 primipararae and multiparae Ghanaian women were screened for Polycyclic Aromatic Hydrocarbons (PAHs) from 2014 and 2016. These were breast milk from women residing or working around an electronic waste recycling site and a reference area (a residential area). This research is aimed at assessing PAHs levels in human milk samples from some Ghanaian mothers, prediction of the sources of these PAHs and the probable carcinogenic and mutagenic risks to infants. PAHs in the breast milk were analyzed using a gas chromatography coupled with a mass spectrometer (GC-MS/MS). A total of 18 PAH congeners were identified in the human milk samples with a total range between <LOD and 15,936.57 ng/g lipid wt and an overall mean of 1105.63 ng/g lipid wt. In general, the mean concentrations of low molecular weight PAHs were appreciably greater than the high molecular weight PAHs in the breast milk samples. Naphthalene recorded the highest mean concentrations of 1026.52 ng/g lipid wt and 78.73 ng/g lipid wt for both e-waste and residential areas, respectively. Naphthalene contributed 77.4% of the total PAHs in the milk samples. Most of the high molecular weight PAHs were below the limit of detection in milk samples from Kwabenya (a residential area) but were detected in the milk samples from Agbogbloshie (e-waste recycling site). The diagnostic ratio tests in this study suggest that most of the PAHs in the milk samples are originating from pyrogenic sources. Risk assessment for carcinogenicity and mutagenicity on infants based on this study were 1.1 × 10^-5 and 1.9 × 10^-5, respectively.

Evaluation of floor-wise pollution status and deposition behavior of potentially toxic elements and nanoparticles in air conditioner dust during urbanistic development

The study was undertaken to investigate deposition behaviors of various size-segregated particles and indoor air quality using dust accumulated on the air conditioner filter acting as a sink for PTEs and nanoparticles that can pose a significant health risk. However, the particulate matter size and chemical composition in AC dust and its relationship with PTEs remains uncertain. Current study aims to investigate the PTEs and nanoparticles composition of AC dust using different analytical approaches including ICP-MS, XRD, XPS, SEM/TEM along with EDS and Laser Diffraction particle size analyzer. The mean concentration of PTEs like Al, As, Cd, Cu, Li, Pb, Sb, Se, Sn, Ti, V and Zn exceeded the corresponding background value. Pb, As, Sn, Sb, Cd were categorizing under geo-accumulation index class IV. Most of the particles were found to be > 100 μm and it decreased significantly with increase in floor altitude. A significantly negative correlation was found between particles size and PTEs concentration showing a significant increase in PTEs content with decrease in particles size. The XPS results showed dominant peaks for TiO₂, Ti-O-N, As₂O₃, Fe⁺³, Fe⁺², Al-OH and Al₂0₃. Additionally, As, Pb, Si and Fe were dominant metallic nanoparticles identified using SEM/TEM along with EDS.

Burden of disease for workers attributable to exposure through inhalation of PPAHs in RSPM from cooking fumes

Polycyclic aromatic hydrocarbons (PAHs), some of which are classified as possible carcinogens (WHO), have been detected in cooking fumes in considerable amounts. Distribution of 24 PAHs on varying particle sizes was analyzed in cooking emission. Analysis of cooking fumes from vegetarian and non-vegetarian food was carried out separately in the kitchen of a hostel mess in IIT Kanpur during November 2012 and February 2013. Respirable suspended particulate matter (RSPM) and particle-bound polycyclic aromatic hydrocarbons (PPAHs) showed a similar sequence regarding concentration observed in vegetarian and non-vegetarian food. PAHs with carcinogenic potential was detected and quantified mostly in the fine particles. Total PAH concentrations in the fine and ultrafine ranges together accounted for > 90% of the total carcinogenic PAHs, highlighting them as primary carriers of PAHs rather than coarser particles. Benzo [a] pyrene (B [a]P) levels contribute > 70% to total carcinogenic potential and > 60%, to mutagenic potential, respectively. The total toxicity impact on the workers due to the PAHs emitted from cooking fumes was 3.374 × 10^-10 DALYs, with B [a] P contributing the most (> 70%) despite its low concentration. Exposure to cooking fumes especially for people involved in this activity on a daily basis (chefs, hostel mess workers, among others) raises health concerns. An extensive examination of impacts due to exposure to emissions in both particle and gas phase on a long-term basis is required.

Identification of hepatotoxicity and renal dysfunction of pyrene in adult male rats

Polycyclic aromatic hydrocarbons (PAHs) are a group of persistent organic pollutants primarily formed from the incomplete combustion of carbonaceous materials, and have adverse effects on human health. In this study, we investigated whether pyrene, a PAH consisting of 4 fused benzene rings, has adverse effects on rat. Adult male Sprague-Dawly rats were treated daily by oral gavage with vehicle (corn oil) or pyrene at doses of 375, 750, 1500, or 2200 mg/kg/day for 4 days. The results showed that pyrene caused hepatotoxicity in rats. When compared with the control group, relative liver weights, plasma alanine aminotransferase, and direct bilirubin levels significantly increased after pyrene exposure. Hepatocyte swelling and degeneration and decreased hepatic total glutathione (GSH) levels were also found in pyrene-exposed rats. We further observed that mRNA levels of several hepatic metabolizing enzymes regulated by constitutive androstane receptor (CAR) such as CYP2B1 and CYP2B2 significantly increased in pyrene-exposed rats. These results suggest that decreased GSH levels, elevated hepatic metabolizing enzyme gene expression, and CAR activation are important contributors for pyrene-induced hepatotoxicity in rats. Additionally, we found pyrene significantly induced plasma inflammatory indices including white blood cell and lymphocyte counts. We also observed that pyrene exposure increased relative weight of kidneys and disrupted kidney function with elevated urea and creatinine levels in rats.

Polycyclic aromatic hydrocarbons in a bakery indoor air: trends, dynamics, and dispersion

Indoor air pollution assessment in work environments remains challenging due to a combination of logistic reasons and availability of costly instrumentation for data acquisition and post-processing. Existing literature focuses on energy production environments, hospitals, and less so on food production spaces. Studies on indoor air quality in bakeries are scarce or even absent. Motivated by this, the present study investigates indoor air quality in a bakery located in Bari province in South Italy, using a combination of approaches including analytical chemistry analyses and computational fluid dynamics to reconstruct the air ventilation in response to air temperature gradients within the working environment. PM_2.5 indoor samplings were collected every 6 h from 7 to 19 April 2013 in the proximity of two bakery ovens powered by gas and wood, respectively. For each sampling day, 4 PM_2.5 samples were collected: from 3:00 to 9:00 h (first), from 9:00 to 13:30 h (second), from 14:00 to 21:00 h (third), and from 21:00 to 3:00 h (fourth). In total, 40 samples were collected. On each sample, several polycyclic aromatic hydrocarbons (PAHs) were determined such as benzo[a]anthracene (228), benzo[b]fluoranthene (252), benzo[k]fluoranthene (252), benzo[a]pyrene (252), benzo[g,h,i]perylene (276), indeno[1,2,3-cd]pyrene (276), and dibenzo[a,h]anthracene (278), the main compounds of 16 priority US Environmental Protection Agency (US-EPA) PAHs in particulate phase. The PAH mean concentrations showed higher values during the first (from 3:00 to 9:00 h) and fourth (from 21:00 to 3:00 h) sampling intervals than the other two with benzo[a]pyrene mean values exceeding the Italian law limit of 1 ng/m³. Taking into account benzo[a]pyrene mean concentration for the first interval and the first plus the second one, which are the hours with the largest working activity, we have estimated that the baker and co-workers are exposed to a cancer risk of 4.3 × 10^-7 and 5.8 × 10^-7, respectively (these values are lower than US-EPA recommended guideline of 10^-6). Our study was complemented by numerical analyses using state-of-the-art computational fluid dynamics to reconstruct at high resolution air movement from the various working places, i.e., the bakery and the selling area which were connected via a door. The numerical simulations were possible given that surface temperature using infrared thermography as well as air temperature was continuously recorded throughout the sampling acquisition. The use of this approach allowed us to estimate the transport and diffusion of benzo[a]pyrene from one area to the other thus complementing the point sampling information. Computational fluid dynamic simulation results confirm the presence of benzo[a]pyrene in the laboratory as obtained from the measurements and suggests its presence in the sales' area of the bakery with concentrations similar those found in the laboratory.

Contributions of burner, pan, meat and salt to PM emission during grilling

Grilling ground beef meat was conducted in two locations at Nazarbayev University, Kazakhstan. The experiments were designed such that only particles from beef meat were isolated. A similar experimental protocol was applied at both locations. The average particle number and mass emission rates for grilling pure meat itself (excluding particles from pan and burner) were found to be 9.4 × 10¹²(SD = 7.2 × 10¹² particle min^-1 and 7.6 × 10 (SD = 6.3 × 10) mg.min^-1, respectively. The PM emissions (number and mass) from the burner were found to be negligible compared to the pan and meat emissions. Ultrafine particle (UFP) concentrations from the heated pan itself were comparable to those of grilled meat. However, the particle mass concentrations from the pan itself were negligible. Approximately an hour of continuous heating resulted in zero emissions from the pan.

Emission Rates of Multiple Air Pollutants Generated from Chinese Residential Cooking

Household air pollution generated from cooking is severe, especially for Chinese-style cooking. We measured the emission rates of multiple air pollutants including fine particles (PM_2.5), ultrafine particles (UFPs), and volatile organic compounds (VOCs, including formaldehyde, benzene, and toluene) that were generated from typical Chinese cooking in a residential kitchen. The experiment was designed through five-factor and five-level orthogonal testing. The five key factors were cooking method, ingredient weight, type of meat, type of oil, and meat/vegetable ratio. The measured emission rates (mean value ± standard deviation) of PM_2.5, UFPs, formaldehyde, total volatile organic compounds (TVOCs), benzene, and toluene were 2.056 ± 3.034 mg/min, 9.102 ± 6.909 × 10¹² #/min, 1.273 ± 0.736 mg/min, 1.349 ± 1.376 mg/min, 0.074 ± 0.039 mg/min, and 0.004 ± 0.004 mg/min. Cooking method was the most influencing factor for the emission rates of PM_2.5, UFPs, formaldehyde, TVOCs, and benzene but not for toluene. Meanwhile, the emission rate of PM_2.5 was also significantly influenced by ingredient weight, type of meat, and meat/vegetable ratio. Exhausting the range hood decreased the emission rates by approximately 58%, with a corresponding air change rate of 21.38/h for the kitchen room.

Determination and risk assessment of sixteen polycyclic aromatic hydrocarbons in vegetables

Polycyclic aromatic hydrocarbons (PAHs) are a group of organic environmental pollutants posing a potential risk to human health. This study was constructed to investigate the presence of 16 PAHs in six commonly consumed vegetables collected from the markets in Shandong, China by a quick, easy, cheap, effective, rugged, safe (QuEChERS)-based extraction method coupled with gas chromatography-mass spectrometry (GC-MS). Our results showed that the vegetables were polluted with PAHs at an alarming level, of which celery contained the highest total concentration of PAHs (Σ16 PAH), whereas cucumbers contained the lowest Σ16 PAH. Besides, the dietary exposure of PAHs was assessed in these vegetables based on the maximum Σ16 PAH. The results showed that the populations in Shandong were exposed to 23-213 ng/d of PAHs through these six vegetables, suggesting that vegetables are the major sources of PAHs in the diet. Hence, it is necessary to monitor the PAH levels in vegetables. Our study provides guidance for future legislative actions regarding PAH levels in vegetables in China.

Chemical characteristic of PM2.5 emission and inhalational carcinogenic risk of domestic Chinese cooking

To illustrate chemical characteristic of PM_2.5 emission and assess inhalational carcinogenic risk of domestic Chinese cooking, 5 sets of duplicate cooking samples were collected, using the most used 5 types of oil. The mass abundance of 14 elements, 5 water-soluble ions, organic carbon (OC), elemental carbon (EC) and 11 polycyclic aromatic hydrocarbons (PAHs) were calculated; the signature and diagnostic ratio of cooking in the domestic kitchen were analyzed; and carcinogenic risks of heavy metals and PAHs via inhalation were assessed in two scenarios. The analysis showed that OC was the primary composition in the chemical profile; Na was the most abundant element that might be due to the usage of salt; Cr and Pb, NO₃^- and SO₄^2-, Phe, FL and Pyr were the main heavy metals/water-soluble ions/PAHs, respectively. Phe and FL could be used to separate cooking and stationary sources, while diagnostic ratios of BaA/(BaA + CHR), BaA/CHR, BaP/BghiP and BaP/BeP should be applied with caution, as they were influenced by various cooking conditions. Carcinogenic risks of heavy metals and PAHs were evaluated in two scenarios, simulating the condition of cooking with no ventilation and with the range hood on, respectively. The integrated risk of heavy metals and PAHs was 2.7 × 10^-3 and 5.8 × 10^-6, respectively, during cooking with no ventilation. While with the usage of range hood, only Cr(VI), As and Ni might induce potential carcinogenic risk. The difference in the chemical abundance in cooking sources found between this and other studies underlined the necessity of constructing locally representative source profiles under real conditions. The comparison of carcinogenic risk suggested that the potentially adverse health effects induced by inorganic compositions from cooking sources should not be ignored. Meanwhile, intervention methods, such as the operation of range hood, should be applied during cooking for health protection.

Quantifying trace elements in the emitted particulate matter during cooking and health risk assessment

Particulate matter (PM) measurements were conducted during heating corn oil, heating corn oil mixed with the table salt and heating low fat ground beef meat using a PTFE-coated aluminum pan on an electric stove with low ventilation. The main objectives of this study were to measure the size segregated mass concentrations, emission rates, and fluxes of 24 trace elements emitted during heating cooking oil or oil with salt and cooking meat. Health risk assessments were performed based on the resulting exposure to trace elements from such cooking activities. The most abundant elements (significantly different from zero) were Ba (24.4 ug m^-3) during grilling meat and Ti during heating oil with salt (24.4 ug m^-3). The health assessment indicates that the cooking with an electric stove with poor ventilation leading to chronic exposures may pose the risk of significant adverse health effects. Carcinogenic risk exceeded the acceptable level (target cancer risk 1 × 10^-6, US EPA 2015) by four orders of magnitude, while non-carcinogenic risk exceeded the safe level (target HQ = 1, US EPA 2015) by a factor of 5-20. Cr and Co were the primary contributors to the highest carcinogenic and non-carcinogenic risks, respectively.

Cooking smoke and respiratory symptoms of restaurant workers in Thailand

Background

Restaurant workers are at risk from exposure to toxic compounds from burning of fuel and fumes from cooking. However, the literature is almost silent on the issue. What discussion that can be found in the literature focuses on the potential effects from biomass smoke exposure in the home kitchen, and does not address the problem as occurring in the workplace, particularly in restaurants.

Methods

This was a cross-sectional survey of 224 worker from 142 food restaurants in the Tha Pho sub-district of Phitsanulok, a province in Thailand. The standard questionnaire from the British Medical Research Council was used to collect data on chronic respiratory symptoms, including cough, phlegm, dyspnea, severe dyspnea, stuffy nose in the participating workers. Data on their health symptoms experienced in the past 30 days was also asked. A constructed questionnaire was used to collect exposure data, including type of job, time in the kitchen, the frequency of frying food, tears while cooking (TWC), the type of restaurant, fuel used for cooking, the size and location of the kitchen, and the exhaust system and ventilation. The prevalence of the symptoms was compared with those obtained from 395 controls, who were neighbors of the participants who do not work in a restaurant.

Results

In comparison to the control group, the restaurant workers had twice or more the prevalence on most of the chronic health symptoms. Men had a higher risk for “dyspnea”, “stuffy nose” and “wheeze” while women had higher risk of “cough”. A Rate Ratio (RR) of susceptibility was established, which ranged from 1.4 up to 9.9. The minimum RR was for women with “severe dyspnea” (RR of 1.4, 95%CI 0.8, 2.5) while the men showed the maximum RR of 9.9 (95%CI 4.5–22.0) for “wheeze”. Possible risk factors identified were job description, job period, size of restaurant, kitchen location, type of cooking oil, hours of stay in the kitchen area, number of fry dishes prepared, frequency of occurrence of TWC, and additional cooking at home. Working for 6–10 year increased the risk of “cough” with an Odd Ratio (OR) of 3.19 (P < 0.01) while working for more than 10 years increased the risk of “cough” (OR = 3.27, P < 0.01), “phlegm” (OR = 3.87, P = 0.01) and “wheeze” (OR = 2.38, P = 0.05). Working as a chef had a higher risk of “cough” by 2.33 (P = 0.01) as comparing to other jobs. Workers in a relatively large restaurant using 4 or more stoves had increased risk of “wheeze” with OR of 3.81 (P < 0.01) and “stuffy nose” with OR of 3.56 (P < 0.01). Using vegetable oil increased the risk of “stuffy nose” by 2.94 (P < 0.01). Every 10 h of stay in the kitchen area was associated with a minimal increase in the risk of “cough”, “wheeze” and “symptoms in the past 30 days” by 1.15 (P = 0.02), 1.16 (P = 0.01) and 1.16 (P = 0.02), respectively.

Conclusions

Restaurant workers are at risk of respiratory symptoms caused by exposure to toxic compounds from cooking fumes. Job description, job period, size of restaurant, kitchen location, type of cooking oil, hours of stay in the kitchen area, number of fry dishes prepared, frequency of occurrence of TWC, and additional cooking at home were the predictive factors. Workplace Health and Safety protection of restaurant worker is urgently needed and the issue should receive more public attention.

Exposure to particulate matter in India: A synthesis of findings and future directions

Air pollution poses a critical threat to human health with ambient and household air pollution identified as key health risks in India. While there are many studies investigating concentration, composition, and health effects of air pollution, investigators are only beginning to focus on estimating or measuring personal exposure. Further, the relevance of exposures studies from the developed countries in developing countries is uncertain. This review summarizes existing research on exposure to particulate matter (PM) in India, identifies gaps and offers recommendations for future research. There are a limited number of studies focused on exposure to PM and/or associated health effects in India, but it is evident that levels of exposure are much higher than those reported in developed countries. Most studies have focused on coarse aerosols, with a few studies on fine aerosols. Additionally, most studies have focused on a handful of cities, and there are many unknowns in terms of ambient levels of PM as well as personal exposure. Given the high mortality burden associated with air pollution exposure in India, a deeper understanding of ambient pollutant levels as well as source strengths is crucial, both in urban and rural areas. Further, the attention needs to expand beyond the handful large cities that have been studied in detail.

Characteristics of PAHs from deep-frying and frying cooking fumes

Cooking fumes are an important indoor source of polycyclic aromatic hydrocarbons (PAHs). Because indoor pollution has a more substantial impact on human health than outdoor pollution, PAHs from cooking fumes have drawn considerable attention. In this study, 16 PAHs emitted through deep-frying and frying methods using rapeseed, soybean, peanut, and olive oil were examined under a laboratory fume hood. Controlled experiments were conducted to collect gas- and particulate-phase PAHs emitted from the cooking oil fumes, and PAH concentrations were quantified via high-performance liquid chromatography (HPLC). The results show that deep-frying methods generate more PAHs and benzo[a]pyrene (B[a]P) (1.3 and 10.9 times, respectively) because they consume greater volumes of edible oil and involve higher oil temperatures relative to those of frying methods. In addition, the total B[a]Peq concentration of deep-frying is 2.2-fold larger than that of frying. Regarding the four types of edible oils studied, rapeseed oil produced more PAH emission than the other three oil varieties. For all of the cooking tests, three- and four-ringed PAHs were the main PAH components regardless of the food and oil used. Concerning the PAH partition between gas and particulate phase, the gaseous compounds accounted for 59-96 % of the total. Meanwhile, the particulate fraction was richer of high molecular weight PAHs (five-six rings). Deep-frying and frying were confirmed as important sources of PAH pollution in internal environments. The results of this study provide additional insights into the polluting features of PAHs produced via cooking activities in indoor environments.