Importance of Dermal Absorption of Polycyclic Aromatic Hydrocarbons Derived from Barbecue Fumes

Exposure to polycyclic aromatic hydrocarbons (PAHs) from domestic heating and cooking combustion of different fuel types for elders in rural China

Solid fuel combustion emitted abundant pollutants, especially polycyclic aromatic hydrocarbons (PAHs) which had significant minus impact on human health in rural China. PAHs in PM2.5 emitted from different fuels combustion and hydroxylated metabolites of PAHs (OH-PAHs) in urine samples of different fuel users were detected in this study. The indoor PAHs were higher than that in outdoors for solid fuel use households, and the concentration of PAHs in the indoor of liquefied petroleum gas (LPG) use household was not much lower than solid fuel use households. Biogas-use household produced the lowest PAHs, which significantly reduced 64-82% compared with those emitted by solid fuel combustion. The different combustion conditions influenced the gaseous PAHs in indoors between two sampling sites. The gas/particle partition indicated that PAHs tended to occur in the particle phase with increased molecular weight, and the absorption was the main mechanism. The relative higher contribution of high molecular weight PAHs (HMW-PAHs) in solid fuel use households than in clean fuel use households, induced more health risks of PAHs. The concentration of Σ10OH-PAHs in the urine samples for elders of different fuel-use households displayed the trend of coal (83.27 ng/mL) > wood (79.32 ng/mL) > LPG (51.61 ng/mL) > biogas (28.96 ng/mL), and OH-NaPs was the predominant metabolites, which accounted for more than 90% of the total concentration. The carcinogenic risk of PAHs based on internal exposure was greater than or close to 10-4, with serious carcinogenic risks. This was different with the incremental lifetime cancer risk based on the atmospheric concentrations. The exposure of PAHs from solid fuel combustion for human being especially for the elders in this region should be concerned, and more data should be done for the internal exposure of PAHs.

Polycyclic aromatic hydrocarbon skin permeation efficiency in vitro is lower through human than pigskin and decreases with lipophilicity

Polycyclic aromatic hydrocarbons (PAH) are persistent environmental pollutants, which occasionally appear as contaminants in consumer products. Upon dermal contact, transfer of PAH into the stratum corneum (s.c.) and migration through the skin may occur, resulting in this class of highly toxic compounds to become bioavailable. In this study, dermal penetration through human and porcine skin of 24 PAH, comprising broad molar mass (M: 152-302 g/mol) and octanol-water partition coefficient (logP: 3.9-7.3) ranges, was evaluated via Franz diffusion cell in vitro assays. More lipophilic and potentially more toxic PAH had decreased permeation rates through the rather lipophilic s.c. into the more hydrophilic viable (epi-)dermis. Furthermore, human skin was less permeable than pigskin, a commonly used surrogate in skin penetration studies. In particular, the s.c. of human skin retains a greater share of PAH, an effect that is more pronounced for smaller PAH. Additionally, we compared the skin permeation kinetics of different PAH in pigskin. While small PAH (M < 230 g/mol, logP < 6) permeate the skin quickly and are detected in the receptor fluid after 2 h, large PAH (M > 252 g/mol, logP ≥ 6) do not fully permeate the skin up to 48 h. This indicates that highly lipophilic PAH do not become bioavailable as readily as their smaller congeners when transferred to the skin surface. Our data suggest that pigskin could be used as a surrogate for worst case scenario estimates of dermal PAH permeation through human skin.

Exposure biomarker profiles of polycyclic aromatic hydrocarbons based on a rat model using a versatile analytical framework

Polycyclic aromatic hydrocarbons (PAHs) are an important group of organic toxic pollutants. Parent PAHs (pPAHs) are mainly metabolized into mono-hydroxylated PAHs (OH-PAHs) after entering the human body. Until now, it is still an urgent need to select appropriate exposure biomarkers for PAHs and analyze them at the trace level. Based on gas chromatography coupled with triple-quadrupole tandem mass spectrometry, we have developed a versatile analytical method for the systemic analysis of pPAHs and OH-PAHs in routinely collected biological samples. This method was further applied to analyze plasma, hair and urine samples from 24 rats exposed to 13 pPAH congeners at four levels. The detection rate for pPAHs in three types of samples was 100%, except for dibenz(a,h)anthracene (DahA) in plasma, while the detection rate for OH-PAHs ranged from 25% to 100%. A significant linear relationship was observed between pPAH exposure levels and their corresponding OH-PAH levels in three different types of samples. It was found that each unit increase in pPAH exposure level was associated with an increase in OH-PAHs ranging from 0.03% (0.01-0.05%) to 5.27% (1.74-8.81%). Furthermore, significant positive correlations were found between any two types of samples for most OH-PAHs, but not observed for most pPAHs. The correlation patterns of 1-hydroxypyrene (1-OH-PYR) across three types of samples differed from other congeners. Strong correlations were identified between five types of hydroxyphenanthrene (OH-PHE) and pPAH exposure levels. In conclusion, OH-PAHs were more sensitive exposure biomarkers than pPAHs, particularly in hair and urine samples.

A review of hazards in meat products: Multiple pathways, hazards and mitigation of polycyclic aromatic hydrocarbons

Polycyclic aromatic hydrocarbons (PAHs) are stable carcinogens that are widely distributed in the environment and food, and humans are exposed to PAHs primarily through the respiratory tracts, dermal contact, and dietary intake. Meat products are an essential part of the human diet, and the formation of PAHs during meat processing is unavoidable. Therefore, a comprehensive understanding of PAHs in meat products can be a contribution to the minimization of human exposure dose. The aim of this review is to provide a comprehensive description of the toxicological analysis of PAHs intake and the various production pathways. The distribution of different PAHs in various meat products, including poultry and aquatic products, is analyzed. The discussion focuses on controlling PAHs through the use of endogenous marinades and antioxidants as well as reducing exogenous particulate matter-PAHs attachment. In addition, potential strategies for PAHs reduction and possible directions for future research are proposed.

In-Utero exposure to potential sources of indoor air pollution and umbilical cord blood leukocyte telomere length

Indoor air pollution (IAP) has been associated with various adverse health effects. However, the evidence regarding such an association with leukocyte telomere length (LTL) in cord blood samples is still scarce. Therefore, the present study aimed to assess the relationship between exposure to indicators of IAP and LTL in umbilical cord blood samples. This cross-sectional study was based on 188 mother-newborn pairs who participated in our study between 2020 and 2022 in Isfahan, Iran. Umbilical LTL was measured by quantitative real-time polymerase chain reaction (qRT-PCR) technique. Linear mixed-effect models were used to assess the relationship between IAP indicators and umbilical LTL, adjusted for relevant covariates. The median (interquartile range (IQR)) of umbilical LTL was 0.92 (0.47). In fully adjusted models, frequency of using degreasing spray during pregnancy (times per month) (β = -0.047, 95% CI:0.09, -0.05, P-value = 0.02), using air freshener spray during pregnancy (β = -0.26, 95% CI: -0.5, -0.02, P-value = 0.03) and frequency of using insecticides during pregnancy (times per month) (β = -0.025, 95% CI: -0.047, -0.003, P-value = 0.02) were significantly associated with shorter umbilical LTL. There was a positive significant relationship between the frequency of using cleaning spray during pregnancy (times per month) with umbilical LTL (β = 0.019, 95% CI: 0.005, 0.033, P-value = 0.01). Furthermore, the direct connection of the parking with home and the frequency of using barbecue (times per week) were marginally associated with shorter umbilical LTL. For other indicators of IAP, we did not observe any statistically significant associations. Overall, this study suggested a negative association between prenatal exposure to IAP during pregnancy and umbilical LTL.

Emerging contaminants: A One Health perspective

Environmental pollution is escalating due to rapid global development that often prioritizes human needs over planetary health. Despite global efforts to mitigate legacy pollutants, the continuous introduction of new substances remains a major threat to both people and the planet. In response, global initiatives are focusing on risk assessment and regulation of emerging contaminants, as demonstrated by the ongoing efforts to establish the UN's Intergovernmental Science-Policy Panel on Chemicals, Waste, and Pollution Prevention. This review identifies the sources and impacts of emerging contaminants on planetary health, emphasizing the importance of adopting a One Health approach. Strategies for monitoring and addressing these pollutants are discussed, underscoring the need for robust and socially equitable environmental policies at both regional and international levels. Urgent actions are needed to transition toward sustainable pollution management practices to safeguard our planet for future generations.

Photodegradation enhances the toxic effect of anthracene on skin

Anthracene, a polycyclic aromatic hydrocarbon (PAH), is a widespread environmental pollutant that poses potential risks to human health. Exposure to anthracene can result in various adverse health effects, including skin-related disorders. Photo exposure sufficiently removes the anthracene from the environment but also generates more degradation products which can be more toxic. The goal of this study was to assess the change in anthracene dermotoxicity caused by photodegradation and understand the mechanism of this change. In the present study, over 99.99% of anthracene was degraded within 24 h of sunlight exposure, while producing many intermediate products including 9,10-anthraquinone and phthalic acid. The anthracene products with different durations of photo exposure were applied to 2D and 3D human keratinocyte cultures. Although the non-degraded anthracene significantly delayed the cell migration, the cell viability and differentiation decreased dramatically in the presence of the photodegraded anthracene. Anthracene photodegradation products also altered the expression patterns of a number of inflammation-related genes in comparison to the control cells. Among these genes, il1a, il1b, il8, cxcl2, s100a9, and mmp1 were upregulated whereas the tlr4 and mmp3 were downregulated by the photodegraded anthracene. Topical deliveries of the photodegraded and non-degraded anthracene to the dorsal skin of hairless mice showed more toxic effects by the photodegraded anthracene. The 4-hour photodegradation products of anthracene thickened the epidermal layer, increased the dermal cellularity, and induced the upregulation of inflammatory markers, il1a, il1b, s100a9, and mmp1. In addition, it also prevented the production of a gap junction protein, Connexin-43. All the evidence suggested that photodegradation enhanced the toxicities of anthracene to the skin. The 4-hour photodegradation products of anthracene led to clinical signs similar to acute inflammatory skin diseases, such as atopic and contact dermatitis, eczema, and psoriasis. Therefore, the potential risk of skin irritation by anthracene should be also considered when an individual is exposed to PAHs, especially in environments with strong sunlight.

Photoreactivity of polycyclic aromatic hydrocarbons (PAHs) and their mechanisms of phototoxicity against human immortalized keratinocytes (HaCaT)

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous organic compounds in the environment. They are produced by many anthropogenic sources of different origins and are known for their toxicity, carcinogenicity, and mutagenicity. Sixteen PAHs have been identified as Priority Pollutants by the US EPA, which are often associated with particulate matter, facilitating their dispersion through air and water. When human skin is exposed to PAHs, it might occur simultaneously with solar radiation, potentially leading to phototoxic effects. Phototoxic mechanisms involve the generation of singlet oxygen and reactive oxygen species, DNA damage under specific light wavelengths, and the formation of charge transfer complexes. Despite predictions of phototoxic properties for some PAHs, there remains a paucity of experimental data. This study examined the photoreactive and phototoxic properties of the 16 PAHs enlisted in the Priority Pollutants list. Examined PAHs efficiently photogenerated singlet oxygen and superoxide anion in simple solutions. Furthermore, singlet oxygen phosphorescence was detected in PAH-loaded HaCaT cells. Phototoxicity against human keratinocytes was evaluated using various assays. At 5 nM concentration, examined PAHs significantly reduced viability and mitochondrial membrane potential of HaCaT cells following the exposure to solar simulated light. Analyzed compounds induced a substantial peroxidation of cellular proteins after light treatment. The results revealed that a majority of the examined PAHs exhibited substantial reactive oxygen species photoproduction under UVA and violet-blue light, with their phototoxicity corresponding to their photoreactive properties. These findings improve our comprehension of the interactions between PAHs and human skin cells under environmental conditions, particularly when exposed to solar radiation.

Quantitative characterization of resident' exposure to typical semi-volatile organic compounds (SVOCs) around a non-ferrous metal smelting plant

To comprehensively characterize residents' exposure to major semi-volatile organic compounds (SVOCs), samples of indoor floor wipes, size-segregated airborne particles, gaseous air, food, and paired skin wipes were simultaneously collected from residential areas around a large non-ferrous metal smelting plant as compared with the control areas, and three typical SVOCs (including polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and halogenated PAHs (HPAHs)) were determined. Comparison and correlation analysis among matrices indicated PAHs were the major contaminants emitted from metal smelting activities compared to HPAHs and PCBs, with naphthalene verified as the most important characteristic compound, and their accumulation on skin may be a comprehensive consequence of contact with floor dust and air. While patterns of human exposure pathways for the SVOCs were found to be clearly correlated to their vapor pressure, dermal absorption was the major contributor (51.1-76.3%) to total carcinogenic risk (TCR) of PAHs and HPAHs for surrounding residents, especially for low molecular weight PAHs, but dietary ingestion (98.6%) was the dominant exposure pathway to PCBs. The TCR of PAHs exceeded the acceptable level (1 × 10-4), implying smelting activities obviously elevated the health risk. This study will serve developing pertinent exposure and health risk prevention measures.

Particulate polycyclic aromatic hydrocarbons in rural households burning solid fuels in Xuanwei County, Southwest China: occurrence, size distribution, and health risks

The study is about the size distribution and health risks of polycyclic aromatic hydrocarbons (PAHs) in indoor environment of Xuanwei, Southwest China particle samples were collected by Anderson 8-stage impactor which was used to gather particle samples to nine size ranges. Size-segregated samples were collected in indoor from a rural village in Xuanwei during the non-heating and heating seasons. The results showed that the total concentrations of the indoor particulate matter (PM) were 757 ± 60 and 990 ± 78 μg/m3 in non-heating and heating seasons, respectively. The total concentration of indoor PAHs reached to 8.42 ± 0.53 μg/m3 in the heating season, which was considerably greater than the concentration in the non-heating season (2.85 ± 1.72 μg/m3). The size distribution of PAHs showed that PAHs were mainly enriched in PMs with the diameter <1.1 μm. The diagnostic ratios (DR) and principal component analysis (PCA) showed that coal and wood for residential heating and cooking were the main sources of indoor PAHs. The results of the health risk showed that the total deposition concentration (DC) in the alveolar region (AR) was 0.25 and 0.68 μg/m3 in the non-heating and heating seasons respectively. Throughout the entire sampling periods, the lifetime cancer risk (R) based on DC of children and adults varied between 3.53 ×10-5 to 1.79 ×10-4. During the heating season, the potential cancer risk of PAHs in adults was significant, exceeding 10-4, with a rate of 96%.

Longitudinal Assessment of the Prevalence of Actinic Keratosis and Extensive Risk Factor Evaluation: An Update from the Rotterdam Study

Population-based studies available to analyze the prevalence, risk factors, and longitudinal outlook of actinic keratoses (AKs) are limited. These features mentioned earlier were assessed using Rotterdam study participants aged ≥40 years who underwent a full-body skin examination by a dermatology-trained physician. ORs with 95% confidence intervals were calculated for the associations between risk factors and the presence of AK. Among 8,239 eligible participants, the prevalence of one or more AKs was 21.1% (95% confidence interval = 20.2-22.0) and was higher in men. Male sex, age, lighter hair and eye color, baldness, genetic risk score, and digital photoaging measures (digitally assessed pigmented spots, telangiectasias, and global facial wrinkling) had a positive association with AK. Cigarette smokers had reduced odds of having AK, with current smokers having the lowest risk. Among patients with two AK assessments, there was no difference in the presence of AK during follow-up between treated and untreated participants. In conclusion, genetic risk score and digital photoaging measures showed associations with increased lesion count. At the individual level, patients were most likely to decrease in AK severity group over time, possibly regardless of whether or not participants were treated.

Impact of phenanthrene co-administration on the toxicokinetics of benzo[a]pyrene in humans. UPLC-accelerator mass spectrometry following oral microdosing

Current risk assessments for environmental carcinogens rely on animal studies utilizing doses orders of magnitude higher than actual human exposures. Epidemiological studies of people with high exposures (e.g., occupational) are of value, but rely on uncertain exposure data. In addition, exposures are typically not to a single chemical but to mixtures, such as polycyclic aromatic hydrocarbons (PAHs). The extremely high sensitivity of accelerator mass spectrometry (AMS) allows for dosing humans with known carcinogens with de minimus risk. In this study UPLC-AMS was used to assess the toxicokinetics of [14C]-benzo[a]pyrene ([14C]-BaP) when dosed alone or in a binary mixture with phenanthrene (Phe). Plasma was collected for 48 h following a dose of [14C]-BaP (50 ng, 5.4 nCi) or the same dose of [14C]-BaP plus Phe (1250 ng). Following the binary mixture, Cmax of [14C]-BaP significantly decreased (4.4-fold) whereas the volume of distribution (Vd) increased (2-fold). Further, the toxicokinetics of twelve [14C]-BaP metabolites provided evidence of little change in the metabolite profile of [14C]-BaP and the pattern was overall reduction consistent with reduced absorption (decrease in Cmax). Although Phe was shown to be a competitive inhibitor of the major hepatic cytochrome P-450 (CYP) responsible for metabolism of [14C]-BaP, CYP1A2, the high inhibition constant (Ki) and lack of any increase in unmetabolized [14C]-BaP in plasma makes this mechanism unlikely to be responsible. Rather, co-administration of Phe reduces the absorption of [14C]-BaP through a mechanism yet to be determined. This is the first study to provide evidence that, at actual environmental levels of exposure, the toxicokinetics of [14C]-BaP in humans is markedly altered by the presence of a second PAH, Phe, a common component of environmental PAH mixtures.

Disturbance of OH-PAH metabolites in urine induced by single PAH lab exposure

Due to the high exposure toxicity and individual variability of polycyclic aromatic hydrocarbons (PAHs), it is difficult to accurately characterize the actual exposure of exposed individuals through external exposure detection. In this study, the monohydroxyl metabolites of naphthalene, phenanthrene, pyrene, and 9-fluorenone were identified in the urine of low-dose PAH-exposed individuals based on ultra-performance liquid chromatography-high-resolution mass spectrometry (UPLC-HRMS), and their concentrations were monitored for 15 consecutive days after exposure. The results showed that the metabolite concentrations of naphthalene, phenanthrene, and pyrene were basically the same, and all of them reached the maximum value at day 8. In contrast, the metabolite of 9-fluorenone reached its maximum value on day 2. This study showed that the four metabolites were strongly correlated with their parent PAH exposure, with a wide detection window, and their assays were specific, sensitive, and reliable, while the sampling difficulty was low, so the four hydroxylated PAHs may be potential low-dose biomarkers of PAH internal exposure. This study will provide methodological and data support for further health risk studies involving internal exposure to organic pollutants such as PAHs.

Investigating industrial PAH air pollution in relation to population exposure in major countries: A scoring approach

Polycyclic aromatic hydrocarbons (PAHs) are common air pollutants worldwide, associated with industrial processes. In the general population, both modeling and field studies revealed a positive correlation between air PAH concentrations and urinary PAH metabolite levels. Many countries lack population urinary data that correspond to local PAH air concentrations. Thus, we proposed a scoring-based approximate approach to investigating that correlation in selected countries, hypothesizing that PAH air concentrations in selected regions could represent the national air quality influenced by industrial emission and further correlate to PAH internal exposure in the general population. This research compiled 85 peer-reviewed journal articles and 9 official monitoring datasets/reports covering 34 countries, 16 of which with both atmospheric PAH data and human biomonitoring data. For the air pollution score (AirS), Egypt had the highest AirS at 0.94 and Pakistan was at the bottom of the score ranking at -1.95, as well as the median in the UK (AirS: 0.50). For the population exposure score (ExpS), China gained the top ExpS at 0.44 and Spain was with the lowest ExpS of -1.52, with the median value in Italy (ExpS: 0.43). Through the correlation analysis, atmospheric PAHs and their corresponding urinary metabolites provided a positive relationship to a diverse extent, indicating that the related urinary metabolites could reflect the population's exposure to specific atmospheric PAHs. The findings also revealed that in the 16 selected countries, AirS indexes were positively correlated with ExpS indexes, implying that higher PAH levels in the air may lead to elevated metabolite urinary levels in general populations. Furthermore, lowering PAH air concentrations could reduce population internal PAH exposure, implying that strict PAH air regulation or emission would reduce health risks for general populations. Notably, this study was an ideal theoretical research based on proposed assumptions to some extent. Further research should focus on understanding exposure pathways, protecting vulnerable populations, and improving the PAH database to optimize PAH pollution control.

Occurrence and risk of human exposure to organophosphate flame retardants in indoor air and dust in Hanoi, Vietnam

The presence and distribution of thirteen organophosphate flame retardants (OPFRs) were investigated in indoor air and dust samples collected in Hanoi, Vietnam. The total OPFRs (ƩOPFRs) concentrations in indoor air and dust samples were 42.3-358 ng m^-3 (median 101 ng m^-3) and 1290-17,500 ng g^-1 (median 7580 ng g^-1), respectively. The profile of OPFRs in both indoor air and dust indicated that tris(1-chloro-2-propyl) phosphate (TCIPP) was the most dominant compound with a median concentration of 75.3 ng m^-3 and 3620 ng g^-1, contributing 75.2% and 46.1% to ƩOPFRs concentrations in indoor air and dust, respectively, followed by tris(2-butoxyethyl) phosphate (TBOEP), with a median concentration of 16.3 ng m^-3 and 2500 ng g^-1, contributing 14.1% and 33.6% to ƩOPFRs concentrations in indoor air and dust, respectively. The levels of OPFRs in the indoor air samples and corresponding indoor dust samples showed a strong positive correlation. The total estimated daily intakes (EDI_total) of ƩOPFRs (via air inhalation, dust ingestion, and dermal absorption) for adults and toddlers under the median and high exposure scenarios were 36.7 and 160 ng kg^-1 d^-1, and 266 and 1270 ng kg^-1 d^-1, respectively. Among the investigated exposure pathways, dermal absorption was a primary exposure pathway to OPFRs for both toddlers and adults. The hazard quotients (HQ) ranged from 5.31 × 10^-8 to 6.47 × 10^-2 (<1), and the lifetime cancer risks (LCR) were from 2.05 × 10^-11 to 7.37 × 10^-8 (<10^-6), indicating that human health risks from exposure to OPFRs in indoor environments are not significant.

Effectively removing gaseous polycyclic aromatic hydrocarbons (PAHs) by willow catkins: Do you still dislike the catkins floating?

The floating catkins generated by willow and poplar trees have been criticized for spreading germ and causing fire for decades. It has been found that catkins are with a hollow tubular structure, which made us wonder if the floating catkins can adsorb atmospheric pollutions. Thus, we conducted a project in Harbin, China to investigate whether and how willow catkins could adsorb atmospheric polycyclic aromatic hydrocarbons (PAHs). The results suggest that both the catkins floating in the air and on the ground preferred to adsorb gaseous PAHs rather than particulate PAHs. Moreover, 3- and 4-ring PAHs were the dominating compositions adsorbed by catkins, which significantly increased with exposure time. The gas/catkins partition (K_CG) was defined, which explained why 3-ring PAHs are more easily adsorbed by catkins than by airborne particles when their subcooled liquid vapor pressure is high (log P_L > -1.73). The removal loading of atmospheric PAHs by catkins were estimated as 1.03 kg/year in the center city of Harbin, which may well explain the phenomenon that levels of gaseous and total (particle + gas) PAHs are relatively low in the months with catkins floating reported in peer-reviewed papers.

A multi-pathway exposure assessment for polycyclic aromatic hydrocarbons among residents in the Athabasca oil sands region, Canada

Due to increasing emissions from ongoing development of the oil sands in Northern Alberta, Canada, there is concern that local residents and organisms are experiencing elevated exposures to hazardous contaminants. We modified an existing human bioaccumulation model (ACC-Human) to represent the local food chain in the Athabasca oil sands region (AOSR), the focus of oil sands development in Alberta. We used the model to assess the potential exposure to three polycyclic aromatic hydrocarbons (PAHs) among local residents that have a high intake of locally sourced traditional foods. To place these estimates into context, we complemented them with estimated PAH intake through market foods and smoking. Our approach was able to produce realistic body burdens of the PAHs in aquatic and terrestrial wildlife and in humans, both in magnitude and with respect to the relative difference between smokers and non-smokers. Over the model simulation period (1967-2009), market food was the dominant dietary exposure route for phenanthrene and pyrene, while local food, and in particular local fish, dominated the intake of benzo[a]pyrene. Exposure to benzo[a]pyrene therefore was also predicted to increase over time in concert with expanding oil sands operations. Those smoking at the average rate of Northern Albertans take in an additional amount of all three PAHs that is at least as large as dietary intake. Estimated daily intake rates are below toxicological reference thresholds for all three PAHs. However, daily intake of BaP in adults is only ∼20 fold below those thresholds and is predicted to increase. Key uncertainties in the assessment included the effect of food preparation on the PAH content in food (e.g., smoking of fish), the limited availability of market food contamination data specific to Canada, and the PAH content of the vapor phase of first-hand cigarette smoke. Considering the satisfactory model evaluation, ACC-Human AOSR should be suited to making predictions of future contaminant exposure based on development scenarios in the AOSR or in response to potential emission reduction efforts. It should also be applicable to other organic contaminants of concern released by oil sands operations.

Toxicokinetic analyses of naphthalene, fluorene, phenanthrene, and pyrene in humans after single oral administration

Polycyclic aromatic hydrocarbons (PAHs) are generated by incomplete combustion of organic matter. They have health effects in multiple organs and can cause lung, skin, and bladder cancers in humans. Although data regarding their toxicity is available, information on the absorption, distribution, metabolism, and excretion of PAHs in humans is very limited. In the present study, deuterium-labeled naphthalene (Nap), fluorene (Flu), phenanthrene (Phe), and pyrene (Pyr) were orally administered as a single dose (0.02-0.04 mg/kg) to eight healthy adults. Both serum and urine samples were monitored for 72 h after the exposure. Parent compounds and PAH metabolites (monohydroxy-PAHs; OH-PAHs) were measured by headspace-solid phase microextraction coupled with gas chromatography-mass spectrometry and high-performance liquid chromatography-tandem mass spectrometry, respectively. Based on the time-concentration profiles in serum and urine, non-compartmental analysis was performed, and two-compartment models were constructed and validated for each PAH. Subsequently, all of the parent compounds were rapidly absorbed (T_max: 0.25 to 1.50 h) after oral administration and excreted in urine with a biological half-life (T_1/2) of 1.01 to 2.99 h. The fractional urinary excretion (F_ue) of OH-PAHs ranged from 0.07 % to 11.3 %; their T_1/2 values ranged from 3.4 to 11.0 h. The two-compartment models successfully described the toxicokinetic characteristics of each PAH and its metabolites. F_ue and the two-compartment models could be useful tools for exposure simulation or dose-reconstruction of PAHs. The results of this study will provide useful information for interpreting biomonitoring data of PAHs.

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

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

Handwipes as indicators to assess organophosphate flame retardants exposure and thyroid hormone effects in e-waste dismantlers

Dermal exposure is increasingly recognized as an important pathway for organic pollutant exposure. However, data on dermal exposure are limited, particularly with respect to the health effects. This study evaluated association between organophosphorus flame retardants (OPFRs) in handwipes and internal body burden on workers and adult residents in an electronic waste (e-waste) dismantling area. The impact of dermal exposure to OPFRs on thyroid hormones (THs) served as a biomarker for early effects. Triphenyl phosphate (TPhP) was the most detected compound in handwipes, with median levels of 1180, 200, and 24.0 ng in people identified as e-waste bakers, e-waste dismantlers, and adult residents. Among e-waste dismantlers, TPhP levels in handwipes were positively correlated with paired serum TPhP and urinary diphenyl phosphate (DPhP) levels. In multiple linear regression models controlling for sex, age and smoking, TPhP levels in handwipes of e-waste dismantlers were significantly negatively correlated with three THs used to evaluate thyroid function: serum reverse 3,3',5-triiodo-L-thyronine (rT3), 3,3'-diiodo-L-thyronine (3,3'-T2), and 3,5-diiodo-L-thyronine (3,5-T2). These findings suggest that handwipes can act as non-invasive exposure indicators to assess body burden of dermal exposure to TPhP and health effects on THs of e-waste dismantlers. This study highlights importance of OPFR effect on human THs through dermal exposure.

Polycyclic aromatic hydrocarbons (PAHs): Updated aspects of their determination, kinetics in the human body, and toxicity

Polycyclic aromatic hydrocarbons (PAHs) are legacy pollutants of considerable public health concern. Polycyclic aromatic hydrocarbons arise from natural and anthropogenic sources and are ubiquitously present in the environment. Several PAHs are highly toxic to humans with associated carcinogenic and mutagenic properties. Further, more severe harmful effects on human- and environmental health have been attributed to the presence of high molecular weight (HMW) PAHs, that is PAHs with molecular mass greater than 300 Da. However, more research has been conducted using low molecular weight (LMW) PAHs). In addition, no HMW PAHs are on the priority pollutants list of the United States Environmental Protection Agency (US EPA), which is limited to only 16 PAHs. However, limited analytical methodologies for separating and determining HMW PAHs and their potential isomers and lack of readily available commercial standards make research with these compounds challenging. Since most of the PAH kinetic data originate from animal studies, our understanding of the effects of PAHs on humans is still minimal. In addition, current knowledge of toxic effects after exposure to PAHs may be underrepresented since most investigations focused on exposure to a single PAH. Currently, information on PAH mixtures is limited. Thus, this review aims to critically assess the current knowledge of PAH chemical properties, their kinetic disposition, and toxicity to humans. Further, future research needs to improve and provide the missing information and minimize PAH exposure to humans.

Distribution of flame retardants among indoor dust, airborne particles and vapour phase from Beijing: spatial-temporal variation and human exposure characteristics

The occurrence and distribution of 10 brominated flame retardants (BFRs) and 10 organophosphate flame retardants (OPFRs) were investigated in indoor dust, total suspended particles (TSP), and vapour phase from offices (n = 10), homes (n = 9), and day-care centres (n = 10) in Beijing, China. Three types of samples were collected biweekly from one office and one home over a year to examine temporal trends. BFRs in dust significantly correlated with those in TSP, while OPFRs significantly correlated among all three matrices. In addition, BFRs in dust (ng/g) and TSP (pg/m³) exhibited similar temporal trends with higher levels in the cold season, whereas OPFRs in TSP and vapour phase (pg/m³) showed similar temporal trends with higher levels in the warm season. The geometric mean concentrations of BFRs and OPFRs in the three matrices from the above mentioned three types of indoor microenvironments were used for exposure and health risk estimation, and ∑₇OPFRs showed much higher hazard index (HI) values than ∑₁₀BFRs for all subpopulations, and inhalation of OPFRs was a major risk source. With the volatility of flame retardants (FRs) decreasing, the contribution of dust ingestion and dermal absorption showed an increasing trend, and the contribution of inhalation exhibited a gradual decreasing trend, which implied the dominant exposure pathway to FRs is strongly related to the vapour pressure (25 °C, Pa) of these substances. Using a single type of microenvironment or the collection of samples at a single point in time can lead to overestimation or underestimation of overall exposure and risk for people to some extent. The correlations of FRs in dust, TSP, and vapour phase from indoor microenvironments, as well as their temporal trends were first reported in this study, which will provide a basis for more accurate FR exposure assessments in the future.

A simple device for simulating skin adsorption of polycyclic aromatic hydrocarbons: design and application

Dermal exposure is one of the main ways of human body exposure to atmospheric contaminants such as polycyclic aromatic hydrocarbons (PAHs). The skin type significantly affects the skin adsorption of contaminants. However, this is commonly ignored in assessing the dermal exposure based on the atmospheric concentrations of contaminants. In this study, a simulation device suitable for human dermal pollutant exposure assessment was established, which used polyethylene balloons coated with different doses of glycerol trioleate to simulate oily skin, neutral skin, and dry skin type. The sampling effectiveness of the device was verified, and the device was applied to the skin exposure assessment of atmospheric PAHs at different scenarios. Kinetic experiments indicated a linear adsorption within 6 h. The adsorption kinetic constants (k) of PAHs on the oily surface of the balloon were significantly higher than those on the dry surface, especially for PAHs with high ring numbers. Compared with the calculated skin adsorption based on atmospheric concentrations, the results of this simulation device can better simulate the skin adsorption of atmospheric contaminants on different skin types and in different scenarios. Based on the result of balloon sampling, the dermal exposure of PAH_{3 rings} by oily skin inside the tunnel is up to 5.668 ng/cm²/day, indicating a non-negligible health risk.

Age- and sex-specific dermal exposure of polycyclic aromatic hydrocarbons in the general population of a city in south China

This study assessed the dermal exposure of population to polycyclic aromatic hydrocarbons (PAHs) in a South China city. Skin wipe samples of the face, hand, forearm, and shank were collected from 120 volunteers (50% male and 50% female) belonging to different age groups (preschooler, thresholder, middle-aged, and elderly). Concentrations of PAHs in the skin wipe samples varied from 18 to 27000 ng/m² in the order of face > hand > forearm > shank, regardless of age and gender. The PAH concentrations of bare skin locations were significantly higher in females than in males, while no significant differences were observed for clothing-covered skin locations between genders. The PAH concentrations for faces were significantly higher in the elderly compared to the other groups. The PAH composition was distinct between the four age groups. The dermal exposure levels of total PAHs and total BaP equivalent concentration (BaP_eq) varied from 25.6 to 620 and 0.093-37.4 ng/kg body weight/d, respectively. The dermal exposure levels of total PAHs were significantly higher in females than in males in all age groups except for the middle-aged group. The hand-mouth exposure doses were significantly higher in the preschoolers than in the other age groups. The values of the carcinogenic risk caused by dermal PAH exposure were between 3.5 × 10^-6 and 1.4 × 10^-3 with 29% of the population (35/120) having risk values exceeding significant levels (1 × 10^-4). The thresholder group exhibited the highest risk for PAH dermal exposure among all groups of the population. This study provides a comprehensive evaluation of the age- and gender-related risk of PAH through dermal exposure.

In vitro and in vivo low-dose exposure of simulated cooking oil fumes to assess adverse biological effects

Cooking oil fumes (COFs) represent a major indoor environmental pollutant and exhibit potent mutagenic or carcinogenic health effects caused by containing various heterocyclic aromatic amines (HAAs) and long-chain aldehydes. Despite some evaluation of the cumulative exposure of COFs to cancer cells under high concentration were evaluated, their biological adverse effects with low-dose exposure to healthy cells had been inadequately investigated. Herein, we firstly scrutinized the three selected typically toxic compounds of heterocyclic amine 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 3,8-dimethylammidazo[4,5-f]quinoxalin-2-amine (MeIQx) and trans, trans-2,4-decadienal (TDA)) emitted from COFs. In vitro studies revealed that the PhIP, MeIQx and TDA aerosol particles were negligible toxicity to cancer cells (A549 and HepG-2) but strong cytotoxicity to normal healthy cells (HelF and L02) under 0.5–4 μg/mL low dose exposure based on the reactive oxygen species (ROS) mechanism. In vivo studies demonstrated that PhIP caused significant lung and liver damage after exposure to PhIP for 30 days with mice. These results indicated the direct proof of healthy cell damage even at low-dose exposure to HAAs and aldehydes.

Metabolomics and proteomics study reveals the effects of benzo[a]pyrene on the viability and migration of KYSE-150 esophageal cells

A representative polycyclic aromatic hydrocarbon, benzo[a]pyrene (B[a]P), has been widely detected in environmental compartments and is highly carcinogenic to humans. Oral ingestion of B[a]P is the dominant exposure pathway. The esophagus acts as the first contact point when B[a]P enters the human body. However, its role in the development of human esophageal cancer is rarely discussed. Herein, we employed untargeted metabolomics in combination with proteomics to explore B[a]P-related intracellular responses in human esophageal cell lines. Our results demonstrated that B[a]P exposure induced significant metabolic disorders, further leading to overproduction of reactive oxygen species (ROS) and disturbance of the cellular viability process and migration ability of esophageal cells. In response, glutathione (GSH) was consumed to meet the demand for cellular detoxification, and thioredoxin (TXN) was upregulated to balance the cellular redox. These alterations caused the reregulation of some specific protein families, including S100A proteins, ribosomal proteins, and histone H1 proteins. Such changes impeded the viability and migration of esophageal cells, which could adversely affect wound healing of the epithelium. These cellular responses indicate that B[a]P will cause serious cellular damage to esophageal cells and increase the carcinogenic risk even as a result of short-term exposure. SYNOPSIS: Our omics study demonstrated how benzo[a]pyrene hampered the migration of esophageal cells and proposed a plausible mechanism underlying its carcinogenicity, which may contribute to our understanding of environmental pollutants.

Recognition and Health Impacts of Organic Pollutants with Significantly Different Proportions in the Gas Phase and Size-Fractionated Particulate Phase in Ambient Air

The distributions of organic pollutants in the gas phase and size-fractionated particle phases can largely affect human health risks posed by them. Gas-particle partitioning and particle-size distributions of some known pollutants have been investigated. However, the pollutants which are more likely to enter the human body and cause strong adverse effects may be neglected. In this study, a nontargeted screening approach combining comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry and chemometrics was developed. Eighty-eight compounds with markedly different proportions in the gas phase and PM₁, as well as 50 contaminants with significant differences in PM₁ and particles with diameters of 1-2.5 μm, were identified. Of these compounds, 18 were found in the air for the first time. There were obvious discrepancies between the measured and predicted gas-particle partitioning coefficients for some pollutants, suggesting unexpected environmental fates and health risks. The human daily intakes through inhalation and dermal exposure to these pollutants were estimated with the International Commission on Radiological Protection deposition model and transdermal permeability model. A risk-based prioritization was performed. The results indicated that adverse effects posed by 9H-fluoren-9-one, 2-ethylhexyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, p-cumenol, 2,4-diisocyanato-1-methyl-benzene, bis(2-ethylhexyl) phthalate, perylene, (E)-cinnamaldehyde, 4-methyl-2-nitro-phenol, benzoic acid, and bis(2-methylpropyl) ester hexanedioic acid in ambient air may be more severe than those posed by conventionally monitored pollutants. The findings would facilitate raising concerns about these pollutants before they cause further severe and widespread impacts.

Gas-particle partition and size-segregated distribution of flame retardants in indoor and outdoor air: Reevaluation on the role of fine particles in human exposure

In this study, we investigated the distribution of brominated and organophosphate flame retardants (BFRs and OPFRs) in the paired gaseous and nine size-segregated particulate samples collected from 8 typical indoor compartments and monthly outdoor in Xinxiang, China, respectively. For the indoor environments, total concentrations of FRs (Σ₁₉FRs) in bulk air ranged from 3.9 ng/m³ to 37.5 ng/m³, with that in children recreation center (37.5 ng/m³) and furniture store (28.7 ng/m³) showing highest levels. In the outdoor air, Σ₁₉FRs ranged from 3.1 ng/m³ to 13.6 ng/m³ among the 12 months, with that from late spring and summer being the highest. OPFRs had higher concentration than BFRs, with the total concentration of OPFRs accounting for 77%-99% of ∑₁₉FRs. TCIPP (tris(chloroiso-propyl) phosphate), TCEP (tris(2-chloroethyl) phosphate), TEP (triethyl phosphate) and DBDPE (decabromodiphenyl ethane), BDE-209 (decabromodiphenyl ether) were the predominant analogs. Specifically, BFRs tended to enrich in gas phase indoors and coarse particles (aerodynamic diameters >3.3 μm) outdoors, but OPFRs mainly distributed in coarse particles both indoors and outdoors. The size distribution patterns varied among FRs, with the higher volatile FRs (e.g., TCEP, TCIPP) distributed more uniformly across particulate size. Although the distribution patterns of FRs in air were driven by multiple factors, organic carbon and element carbon in particulate matter had an influence to a certain extent. Health risks from exposure to FRs were characterized via the hazard quotient approaches. The total noncarcinogenic risks of ∑₁₆FRs from inhalation were higher than that from air to skin transport, and the risks resulted from coarse particle-bound ∑₁₆FRs (>3.3 μm) and gas phase were both significantly higher than that from fine fraction (<3.3 μm) in all scenarios, implying that FRs in coarse particles should not be underestimated.

Tracing historical changes, degradation, and original sources of airborne polycyclic aromatic hydrocarbons (PAHs) in Jilin Province, China, by Abies holophylla and Pinus tabuliformis needle leaves

Due to their wide distribution and availability, plant leaves can be considered interesting candidates as biomonitoring substrates for the evaluation of atmospheric pollution. In addition, some species can also retain historical information, for example, related to environmental pollution, due to their leaf class age. In this study, the content of polycyclic aromatic hydrocarbons (PAHs) in Abies holophylla and Pinus tabuliformis needle samples in the function of their class age has been investigated to obtain information regarding the degradation constant for each PAH under investigation (α values ranging from 0.173 to 1.870) and to evaluate the possibility to correlate the presence of PAHs in needles with some important pollution environmental factors. Considering air pollutant variables registered in Jilin Province, interesting correlations (at 95% confidence level) have been found between coal consumption per year and anthracene contents in needles, while fluorene, phenanthrene, and anthracene results correlated with coal consumption. Furthermore, it has been demonstrated that the total PAH concentration in needles, for both species, increased with their age (from 804 to 3604 ng g^-1 dry weight), showing a general tendency to accumulate these substances through years. PAH degradation rates increased instead with molecular complexity. This study could be considered a first trial to obtain historical environmental information by pine needles biomonitoring.

Indoor exposure to phthalates and polycyclic aromatic hydrocarbons (PAHs) to Canadian children: the Kingston allergy birth cohort

BACKGROUND

Canadian children are widely exposed to phthalates and polycyclic aromatic hydrocarbons (PAHs) from indoor sources. Both sets of compounds have been implicated in allergic symptoms in children.

OBJECTIVE

We characterize concentrations of eight phthalates and 12 PAHs in floor dust from the bedrooms of 79 children enrolled in the Kingston Allergy Birth Cohort (KABC).

METHOD

Floor dust was collected from the bedrooms of 79 children who underwent skin prick testing for common allergens after their first birthday. Data were collected on activities, household, and building characteristics via questionnaire.

RESULTS

Diisononyl phthalate (DiNP) and phenanthrene were the dominant phthalate and PAH with median concentrations of 561 µg/g and 341 ng/g, respectively. Benzyl butyl phthalate (BzBP) and chrysene had the highest variations among all tested homes, ranging from 1-95% to 1-99%, respectively.

SIGNIFICANCE

Some phthalates were significantly associated with product and material use such as diethyl phthalate (DEP) with fragranced products and DiNP and DiDP with vinyl materials. Some PAHs were significantly associated with household characteristics, such as benzo[a]pyrene with smoking, and phenanthrene and fluoranthene with the presence of an attached garage. Socioeconomic status (SES) had positive and negative relationships with some concentrations and some explanatory factors. No significant increases in risk of atopy (positive skin prick test) was found as a function of phthalate or PAH dust concentrations.

Competitive and/or cooperative interactions of graphene-family materials and benzo[a]pyrene with pulmonary surfactant: a computational and experimental study

BACKGROUND

Airborne nanoparticles can be inhaled and deposit in human alveoli, where pulmonary surfactant (PS) molecules lining at the alveolar air-water interface act as the first barrier against inhaled nanoparticles entering the body. Although considerable efforts have been devoted to elucidate the mechanisms underlying nanoparticle-PS interactions, our understanding on this important issue is limited due to the high complexity of the atmosphere, in which nanoparticles are believed to experience transformations that remarkably change the nanoparticles' surface properties and states. By contrast with bare nanoparticles that have been extensively studied, relatively little is known about the interactions between PS and inhaled nanoparticles which already adsorb contaminants. In this combined experimental and computational effort, we investigate the joint interactions between PS and graphene-family materials (GFMs) with coexisting benzo[a]pyrene (BaP).

RESULTS

Depending on the BaP concentration, molecular agglomeration, and graphene oxidation, different nanocomposite structures are formed via BaPs adsorption on GFMs. Upon deposition of GFMs carrying BaPs at the pulmonary surfactant (PS) layer, competition and cooperation of interactions between different components determines the interfacial processes including BaP solubilization, GFM translocation and PS perturbation. Importantly, BaPs adsorbed on GFMs are solubilized to increase BaP's bioavailability. By contrast with graphene adhering on the PS layer to release part of adsorbed BaPs, more BaPs are released from graphene oxide, which induces a hydrophilic pore in the PS layer and shows adverse effect on the PS biophysical function. Translocation of graphene across the PS layer is facilitated by BaP adsorption through segregating it from contact with PS, while translocation of graphene oxide is suppressed by BaP adsorption due to the increase of surface hydrophobicity. Graphene extracts PS molecules from the layer, and the resultant PS depletion declines with graphene oxidation and BaP adsorption.

CONCLUSION

GFMs showed high adsorption capacity towards BaPs to form nanocomposites. Upon deposition of GFMs carrying BaPs at the alveolar air-water interface covered by a thin PS layer, the interactions of GFM-PS, GFM-BaP and BaP-PS determined the interfacial processes of BaP solubilization, GFM translocation and PS perturbation.

PIG-A gene mutation as a genotoxicity biomaker in polycyclic aromatic hydrocarbon-exposed barbecue workers

Background

The PIG-A gene mutation assay is a valuable tool for measuring in vivo gene mutations in blood cells. The human PIG-A assay, used as a potential genotoxicity biomarker, is minimally invasive, sensitive, and cost-efficient; however, the relationship between carcinogen exposure and PIG-A mutations is not well understood.

Methods

We investigated the genotoxic effect of red blood cells using PIG-A assay and lymphocyte cytokinesis-block micronucleus test in barbecue restaurant workers (N = 70) exposed to polycyclic aromatic hydrocarbons (PAHs) and self-identified healthy control subjects (N = 56). Urinary PAH metabolites were measured to evaluate internal exposure levels.

Results

Multivariate Poisson regression showed that the PAH-exposed workers exhibited significantly higher PIG-A mutant frequency (MF) (8.04 ± 6.81 × 10^− 6) than did the controls (5.56 ± 5.26 × 10^− 6) (RR = 0.707, 95% CI: 0.615–0.812, P < 0.001). These results indicate that PAH exposure is a risk factor for elevated PIG-A MF. The frequencies of micronuclei (MN) and nuclear buds (NBUD) in the PAH-exposed workers (MN: 3.06 ± 2.07 ‰, NBUD: 1.38 ± 1.02 ‰) were also significantly higher than in the controls (MN: 1.46 ± 0.64 ‰, P < 0.001; NBUD: 0.70 ± 0.60 ‰, P < 0.001). Additionally, PIG-A MFs showed better associations with several urinary hydroxylated PAH metabolites (P_2-OH-Flu = 0.032, r_2-OH-Flu = 0. 268; P_2-OH-Phe = 0.022, r_2-OH-Phe = 0.286; P_3-OH-Phe = 0.0312, r_3-OH-Phe = 0.270; P_4-OH-Phe = 0.018, r_4-OH-Phe = 0.296), while the increase in MN, NPB, and NBUD frequencies was not associated with any OH-PAH metabolites; and high-PAH-exposed workers showed the highest PIG-A MFs. Furthermore, there was a significant association between PIG-A MF and PAH exposure levels (Chi-square test for trend, P = 0.006).

Conclusions

Our results indicate that an increase in PIG-A MF in barbecue workers could reflect the response to PAH exposure, providing evidence of its potential as a genotoxicity biomarker in human risk assessment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41021-021-00230-1.

A Novel Personal Passive Sampler for Collecting Gaseous Phthalates

Dermal absorption of gaseous chemicals is an important contributor to increased health risk and has yet to be adequately addressed due to the lack of available sampling techniques. In the present study, a novel personal passive sampler consisting of a housing (embracing a polydimethylsiloxane (PDMS) disk as the sorbent phase, a membrane filter, and a stainless-steel mesh) and a watchband (traditional wristband) was constructed and used to characterize gaseous phthalates (PAEs) near the air-skin interface. In a real-life setting, the utility of the passive sampler was validated by comparing the composition profiles of PAEs in the PDMS disks and in active samples and watchbands. The compositions of PAEs were consistent in disks and gaseous constituents from ambient air, with low-molecular-weight (<306 g mol^-1) PAEs accounting for 87-100% and approximately 100%, respectively. Appreciable amounts of diisononyl phthalate, diisodecyl phthalate, dinonyl phthalate, and skin lipid (e.g., squalene) were detected in watchbands but not in disks. Apparently, the passive sampler can prevent particles and skin-related chemicals from adhering to the disk and collect gaseous PAEs only. The vast majority of PAEs in watchbands was associated with nongaseous constituents. The present study demonstrated that the sampling strategy is a key factor in exposure assessment.

Measurement of size-segregated airborne particulate bound polycyclic aromatic compounds and assessment of their human health impacts - A case study in a megacity of southwest China

Particle size distribution of particulate polycyclic aromatic compounds (PACs) is one of the important factors controlling human exposure to PACs in air. In this study, size-segregated airborne particle samples were collected in a megacity in southwest China to analyze PACs concentrations and evaluate related health risks. Annual average concentrations of Σ₁₉PAHs (polycyclic aromatic hydrocarbons, 17.4 ng/m³) and Σ₁₀OPAHs (oxygenated PAHs, 15.3 ng/m³) were one order of magnitude higher than those of Σ₉MPAHs (methyl PAHs, 0.97 ng/m³) and Σ₂₇NPAHs (nitrated PAHs, 1.54 ng/m³). More than 55% of PACs masses were associated with fine particles (aerodynamic diameter D_ae < 2.1 μm). Inhalation exposure assessment showed that less than 60% of particulate bound PACs could deposit in the respiratory tract, which implies that the traditional model using ambient concentration of PACs would overestimate the inhalation risk. On the other hand, incremental lifetime cancer risks from dermal absorption (ILCR_derm) were comparable to those from inhalation (ILCR_inh) exposure despite the much lower daily dermal absorption dose than the daily inhalation dose, which implies that the health impact might be underestimated if only considering inhalation exposure. Cancer risks from inhalation exposure were mainly attributed to fine particles while those from dermal exposure were mostly associated with coarse particles. Although neither ILCR_derm nor ILCR_inh exceeded the threshold value of 10^-6 set by USEPA, the total ILCR exceeded this criterion, manifesting potential health risks from exposure to airborne particulate PACs in this region.

Liquid-liquid extraction combined with online cleanup for the simultaneous determination of PAHs by GC-MS/MS and their hydroxylated metabolites by LC-MS/MS in human fingernails

A method was developed for the simultaneous determination of polycyclic aromatic hydrocarbons (PAHs) and their hydroxylated metabolites (OH-PAHs) in human fingernails using liquid-liquid extraction and online purification. After surface decontamination by rinsing with acetone, the fingernails were digested with sodium hydroxide and subjected to liquid-liquid extraction with a mixture of n-hexane and methyl tertbutyl ether. The organic extract was then fractionated using a silica-based solid-phase extraction (SPE) cartridge to obtain a PAH fraction eluted with n-hexane/dichloromethane (v/v, 95:5) and an OH-PAH fraction eluted with dichloromethane/ethyl acetate (v/v, 50:50). The PAH fraction was directly injected into an online gel permeation chromatography-gas chromatography-triple quadrupole tandem mass spectrometry (GPC-GC-MS/MS) system, enabling rapid determination of 16 PAHs. A parallel online SPE liquid chromatography tandem mass spectrometry (LC-MS/MS) method was used to determine 12 OH-PAHs. Validation experiments showed that the recovery of PAH and OH-PAH were within range of 67.4%-105.1% (RSD ≤ 10.1%) and 72.8%-102.3% (RSD ≤ 10.9%), respectively, with limits of quantitation (LOQ) of 0.06-0.8 ng/g and 0.15-3.1 ng/g, respectively. Forty-two human fingernail samples from residents of Southern China were analyzed to establish background PAH and OH-PAH levels in this region. Several PAHs and OH-PAHs were detected, at concentrations of 97.5 to 3,687 ng/g for PAHs and 24.2 to 767 ng/g for OH-PAHs. The dominant homologues were two- and three-ring PAH isomers, notably naphthalene (Nap), fluorene (Flu), and phenanthrene (Phe), as well as the corresponding hydroxylated metabolites 2-OH-Nap, OH-Flu, and OH-Phe. Smoking, consuming barbecued food, and age had no significant effects on PAH exposure, but a larger sample would be required to confirm this finding. The online purification strategy presented here expedites cleanup and purification during analysis of human fingernails and should facilitate non-invasive biomonitoring of PAHs in humans, particularly when analyzing large numbers of samples.

Approach to Predicting the Size-Dependent Inhalation Intake of Particulate Novel Brominated Flame Retardants

The risk of human exposure to particulate novel brominated flame retardants (NBFRs) in the atmosphere has received increasing attention from scientists and the public, but currently, there is no reliable approach to predict the intake of these compounds on the basis of their size distribution. Here, we develop a reliable approach to predict the size-dependent inhalation intake of particulate NBFRs, based on the gas/particle (G/P) partitioning behavior of the NBFRs. We analyzed the concentrations of eight NBFRs in 363 size-segregated particulate samples and 99 paired samples of gaseous and bulk particles. Using these data, we developed an equation to predict the G/P partitioning quotients of NBFRs in particles in different size ranges (K_Pi) based on particle size. This equation was then successfully applied to predict the size-dependent inhalation intake of particulate NBFRs in combination with an inhalation exposure model. This new approach provides the first demonstration of the effects of the temperature-dependent octanol-air partitioning coefficient (K_OA) and total suspended particle concentration (TSP) on the intake of particulate NBFRs by inhalation. In an illustrative case where TSP = 100 μg m^-3, inhalation intake of particulate NBFRs exceeded the intake of gaseous NBFRs when log K_OA > 11.4.

On the Flip Side of Mask Wearing: Increased Exposure to Volatile Organic Compounds and a Risk-Reducing Solution

Surgical masks have been worn by the public worldwide during the COVID-19 pandemic, yet hazardous chemicals in the petroleum-derived polymer layer of masks are currently ignored and unregulated. These organic compounds pose potential health risks to the mask wearer through dermal contact or inhalation. Here, we show that surgical masks from around the world are loaded with semivolatile and volatile organic compounds (VOCs), including alkanes, polycyclic aromatic hydrocarbons (PAHs), phthalate esters, and reactive carbonyls at ng to μg/mask levels. Naphthalene was the most abundant mask-borne PAH, accounting for over 80% of total PAH levels; acrolein, a mutagenic carbonyl, was detected in most of the mask samples, and di(2-ethylhexyl) phthalate, an androgen antagonist, was detected in one-third of the samples. Furthermore, there is large mask-to-mask variability of the residue VOCs, revealing the uneven quality of masks. We confirm that masks containing more residue VOCs lead to significantly higher exposure levels and associated disease risks to the wearer, which should warrant the attention of the general public and regulatory agencies. We find that heating the masks at 50 °C for as short as 60 min lowers the total VOC content by up to 80%, providing a simple method to limit our exposure to mask-borne VOCs.

E-waste polycyclic aromatic hydrocarbon (PAH) exposure leads to child gut-mucosal inflammation and adaptive immune response

Polycyclic aromatic hydrocarbon (PAH) exposure alters immunological responses. Research concerning PAH exposure on intestinal immunity of children in electronic waste (e-waste) areas is scarce. The aim of this study was to evaluate the effects of polycyclic aromatic hydrocarbon (PAH) pollutants on intestinal mucosal immunity of children in e-waste areas. Results showed higher hydroxylated PAH (OH-PAH) concentrations in e-waste-exposed children, accompanied with higher sialyl Lewis A (SLA) level, absolute lymphocyte and monocyte counts, decreased of percentage of CD4⁺ T cells, and had a higher risk of diarrhea. OH-PAH concentrations were negative with child growth. 1-OHNap mediated through WBCs, along with 1-OHPyr, was correlated with an increase SLA concentration. 2-OHFlu, 1-OHPhe, 2-OHPhe, 1-OHPyr, and 6-OHChr were positively correlated with secretory immunoglobulin A (sIgA) concentration. Our results indicated that PAH pollutants caused inflammation, affected the intestinal epithelium, and led to transformation of microfold cell (M cell). M cells initiating mucosal immune responses and the subsequent increasing sIgA production might be an adaptive immune respond of children in the e-waste areas. To our knowledge, this is the first study of PAH exposure on children intestinal immunity in e-waste area, showing that PAH exposure plays a negative role in child growth and impairs the intestinal immune function.

Fine Particulate Matter-Induced Oxidative Stress Mediated by UVA-Visible Light Leads to Keratinocyte Damage

The human skin is exposed to various environmental factors including solar radiation and ambient air pollutants. Although, due to its physical and biological properties, the skin efficiently protects the body against the harm of environmental factors, their excessive levels and possible synergistic action may lead to harmful effects. Among particulate matter present in ambient air pollutants, PM2.5 is of particular importance for it can penetrate both disrupted and intact skin, causing adverse effects to skin tissue. Although certain components of PM2.5 can exhibit photochemical activity, only a limited amount of data regarding the interaction of PM2.5 with light and its effect on skin tissue are available. This study focused on light-induced toxicity in cultured human keratinocytes, which was mediated by PM2.5 obtained in different seasons. Dynamic Light Scattering (DLS) and Atomic Force Microscopy (AFM) were employed to determine sizes of the particles. The ability of PM2.5 to photogenerate free radicals and singlet oxygen was studied using EPR spin-trapping and time-resolved singlet oxygen phosphorescence, respectively. Solar simulator with selected filters was used as light source for cell treatment to model environmental lightning conditions. Cytotoxicity of photoexcited PM2.5 was analyzed using MTT assay, PI staining and flow cytometry, and the apoptotic pathway was further examined using Caspase-3/7 assay and RT-PCR. Iodometric assay and JC-10 assay were used to investigate damage to cell lipids and mitochondria. Light-excited PM2.5 were found to generate free radicals and singlet oxygen in season-dependent manner. HaCaT cells containing PM2.5 and irradiated with UV-Vis exhibited oxidative stress features-increased peroxidation of intracellular lipids, decrease of mitochondrial membrane potential, enhanced expression of oxidative stress related genes and apoptotic cell death. The data indicate that sunlight can significantly increase PM2.5-mediated toxicity in skin cells.

The human and ecological risks of neonicotinoid insecticides in soils of an agricultural zone within the Pearl River Delta, South China

Neonicotinoid insecticides (NIIs) are extensively used worldwide and frequently detected in the environment. The human and ecological risks associated with the occurrence of NIIs in agricultural zones are of high importance. The present study highlights the regional occurrence and human exposure risks of NIIs in agricultural soil within the Pearl River Delta (PRD), South China. Six neonicotinoids, i.e., imidacloprid, clothianidin, acetamiprid, imidaclothiz, dinotefuran, and flonicamid, were measured in 351 soil samples from Zengcheng, a typical agricultural zone. The soil samples were categorized into three groups based on cultivated plants: vegetables, rice, and fruits. At least one of these neonicotinoid insecticides was detected in 95% of the soil samples. The levels of ∑₆NII (range (median)) were 0.26-390 (23), 0.26-280 (6.1), and 0.26-120 (5.0) ng g^-1 dry weight in soil samples from vegetable farms, rice paddies, and fruit farms, respectively. Neonicotinoids were detected more frequently and at statistically higher concentrations in vegetable farms than in both rice paddies and fruit farms. This is likely ascribed to higher application frequencies of NIIs in vegetable farms due to higher planting frequencies. The hazard index values for human exposure to NIIs in the agricultural soils were all below 1, suggesting negligible non-cancer risks. The current residual levels of NIIs in the soils could however pose sub-lethal or acute effects to non-target terrestrial organisms such as earthworms. The present study suggests that more information is needed regarding NIIs contamination in soils from agricultural regions of South China to ensure that human and ecological risk from exposure to these compounds can be fully addressed.

Tracing human footprint and the fate of atmospheric polycyclic aromatic hydrocarbons over the Pearl River Estuary, China: Importance of particle size

Few studies have focus on size-segregated particulate polycyclic aromatic hydrocarbons (PAHs) in the oceanic atmosphere. To better understand the impacts of anthropogenic activities on atmospheric PAHs, a heavily human-impacted estuary, the Pearl River Estuary (PRE), was chosen as a case study. We collected gaseous and size-segregated particulate samples of ambient air at two sites in the PRE, as well as from the exhaust emissions of the cruise ship used in the sampling campaign. In addition, surface seawater samples were collected. Size distribution patterns of high molecular-weight (HMW) particulate PAHs were bimodal at one site and unimodal at the other, suggesting PAHs at the former site were derived not only from long-range atmospheric transport but also from local sources. Gas-particle partition coefficients of HMW PAHs in size-segregated particles varied with particle sizes, mostly higher in fine particles (<1.8 μm). Dry deposition flux of Σ₂₃PAHs (defined as the sum of 23 PAHs) was contributed mainly from coarse particles (>1.8 μm), and HMW PAHs with lower dry deposition velocities could be transported farther away. With respect to air-water exchange, lower MW PAHs tended to have net volatilization, whereas higher MW PAHs were likely to have net deposition. This study sheds new lights on the origins and fate of atmospheric PAHs over the PRE, and suggests the emissions of maritime traffics should be regulated. Collected near the metropolitan regions, atmospheric PAHs over the PRE were highly affected by anthropogenic activities, especially for HMW PAHs, which could pose a long-lasting impact to the oceanic atmosphere and marine organisms.

Polycyclic aromatic hydrocarbon exposure, oxidative potential in dust, and their relationships to oxidative stress in human body: A case study in the indoor environment of Guangzhou, South China

A comparative study of internal and external exposure is a good method to comprehensively understand human exposure to environmental contaminants that may trigger oxidative stress in human body. Information is limited regarding the influences of reactive oxygen species (ROS) on human health from the environment. In addition, data on the contribution of polycyclic aromatic hydrocarbons (PAHs) from indoor environments, especially air, to total human exposure are still insufficient. The present study measured PAHs in paired indoor dust (n = 101), gas (polyurethane foams, n = 100), and particle samples (quartz fiber filters, n = 100) and their hydroxy metabolites (OH-PAHs) in 205 urine samples from 101 families in Guangzhou, South China. The oxidative potential (OP) in dust samples was quantified with a dithiothreitol (DTT) assay to reflect the oxidizability of ROSs, and explore the relationship between environmental ROSs and oxidative stress in humans (using urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) as a biomarker). The estimated daily intakes (EDIs) of Σ₁₆PAH via air inhalation were much higher than those from gas dermal contact, dust dermal contact, and dust ingestion (mean: 19.5 > 4.27 > 3.75 > 1.60 ng/kg_bw/day). Generally, approximately 16% of naphthalene, 28% of fluorene, 9% of phenanthrene, and 3% of pyrene were derived from indoor environments for all residents when compared with the total PAH exposure amount from all sources. Significantly positive relationships were found between OH-PAHs and 8-OHdG (coefficients β: 0.129-0.366, p < 0.05) checked by linear mixed effect models, and males seemed to be more susceptible than females to the DNA oxidative damage related to PAH exposure. The mean OP value in dust was 7.14 ± 6.68 pmol/(min·μg). Individual PAHs in dust gradually intensified the oxidizability of dust particles as their molecular weight increased. A potential but not significant dose-relationship was found between dusty OP and urinary 8-OHdG. Further work should determine the impact of chemical profiles on OP in different environmental media and continuously explore the potential to use OP as a useful indicator to reflect the total oxidizability of several groups of environmental pollutants.

PAH exposure is associated with enhanced risk for pediatric dyslipidemia through serum SOD reduction

BACKGROUND

Exposure to polycyclic aromatic hydrocarbons (PAHs) is linked to abnormal lipid metabolism, but evidence regarding PAHs as risk factors for dyslipidemia is lacking.

OBJECTIVE

To investigate the respective role and interaction of PAH exposure and antioxidant consumption in the risk for pediatric dyslipidemia.

METHODS

We measured the concentrations of serum lipids, superoxide dismutase (SOD) and urinary hydroxylated PAHs (OH-PAHs) in 403 children, of which 203 were from an e-waste-exposed area (Guiyu) and 200 were from a reference area (Haojiang). Biological interactions were calculated by additive models.

RESULTS

Guiyu children had higher serum triglyceride concentration and dyslipidemia incidence, and lower serum concentration of high-density lipoprotein (HDL) than Haojiang children. Elevated OH-PAH concentration, and concomitant SOD reduction, were both associated with lower HDL concentration and higher hypo-HDL risk (∑₃OH-Phes: B for lgHDL = -0.048, P < 0.01; OR for hypo-HDL = 3.708, 95% CI: 1.200, 11.453; SOD: B_T3 for lgHDL = 0.061, P < 0.01; OR_T3 for hypo-HDL = 0.168, 95% CI: 0.030, 0.941; all were adjusted for confounders). Biological interaction between phenanthrol exposure and SOD reduction was linked to dyslipidemia risk (RERI = 2.783, AP = 0.498, S = 2.537). Children with both risk factors (higher ∑₃OH-Phes and lower SOD) had 5.594-times (95% CI: 1.119, 27.958) the dyslipidemia risk than children with neither risk factors (lower ∑₃OH-Phes and higher SOD).

CONCLUSION

High PAH exposure combined with SOD reduction is recommended for predicting elevated risk for pediatric dyslipidemia. Risk assessment of PAH-related dyslipidemia should take antioxidant concentration into consideration.

Chemical identity and cardiovascular toxicity of hydrophobic organic components in PM2.5

Numerous experimental and epidemiological studies have demonstrated that exposure to PM_2.5 may result in pathogenesis of several major cardiovascular diseases (CVDs), which can be attributed to the combined adverse effects induced by the complicated components of PM_2.5. Organic materials, which are major components of PM_2.5, contain thousands of chemicals, and most of them are environmental hazards. However, the contamination profile and contribution to overall toxicity of PM_2.5-bound organic components (OCs) have not been thoroughly evaluated yet. Herein, we aim to provide an overview of the literature on PM_2.5-bound hydrophobic OCs, with an emphasis on the chemical identity and reported impairments on the cardiovascular system, including the potential exposure routes and mechanisms. We first provide an update on the worldwide mass concentration and composition data of PM_2.5, and then, review the contamination profile of PM_2.5-bound hydrophobic OCs, including constitution, concentration, distribution, formation, source, and identification. In particular, the link between exposure to PM_2.5-bound hydrophobic OCs and CVDs and its possible underlying mechanisms are discussed to evaluate the possible risks of PM_2.5-bound hydrophobic OCs on the cardiovascular system and to provide suggestions for future studies.

Dermal bioaccessibility and absorption of polycyclic aromatic hydrocarbons (PAHs) in indoor dust and its implication in risk assessment

Numerous studies have focused on assessing the risk of human exposure to polycyclic aromatic hydrocarbons (PAHs) in indoor dust via dermal contact. However, the dermal bioaccessibility and dermal absorption of PAHs in indoor dust have seldom been reported. In the present study, the effects of temperature, sweat ratio, solid-liquid ratio and incubation time on the dermal bioaccessibility of PAHs were examined. Naphthalene, phenanthrene, pyrene and benzo[a]pyrenewere selected for examination in an absorption assay with keratinocyte cells. The results showed the release of PAHs from indoor dust fitted a first-order one-compartment model. Naphthalene had the highest rate of release, which was consistent with the bioaccessibility assay results. In addition, the absorption rate of naphthalene and phenanthrene by keratinocytes was higher than that of pyrene and benzo[a]pyrene, with the latter being of higher molecular weight. These results indicated that low molecular weight PAHs were much more easily absorbed via dermal contact than were high molecular weight PAHs. The dermal bioavailability of PAHs in indoor dust was estimated by multiplying the bioaccessibility of PAHs in indoor dust by the ratio of dermal absorption by skin cells, and ranged from 0.12 to 51.0%. These data will be useful in risk assessments.

Size-distribution-based assessment of human inhalation and dermal exposure to airborne parent, oxygenated and chlorinated PAHs during a regional heavy haze episode

The adverse health effects of haze and particle-bound contaminants in China have recently caused increasing concern, and particle size plays a significant role in affecting human exposure to haze-correlated pollutants. To this background, size-segregated particulate samples (nine size fractions (<0.4, 0.4-0.7, 0.7-1.1, 1.1-2.1, 2.1-3.3, 3.3-4.7, 4.7-5.8, 5.8-9.0 and > 9.0 μm) were collected in three scale-gradient cities in northern China and analysed for a series of parent, oxygenated and chlorinated polycyclic aromatic hydrocarbons (PAHs, O-PAHs and Cl-PAHs). The total geometric mean concentrations of PAHs and O-PAHs for Beijing, Zhengzhou and Xinxiang were 98.1 and 27.2, 77.9 and 77.5, 41.0 and 30.7 ng m^-3, respectively, which were 50-200 times higher than those for Cl-PAHs (0.5, 0.7 and 0.4 ng m^-3). Though unimodal size-distribution patterns were found for all these contaminants for these three cities, PAHs represented distinctly higher concentration levels around the peak fraction (0.7-2.1 μm) than O-PAHs and Cl-PAHs. With 4-6 ring PAHs as dominant components in all samples, the percentage proportion of 2-3 ring PAHs (ranging from 1% to 26%) generally increased with particle size increasing, implying the sources of these compounds varied little among the 9 size fractions in all three cities. The International Commission on Radiological Protection (ICRP) model and permeability coefficient method were synchronously applied to the size-segregated data for inhalation and dermal exposure assessment to intensively estimate the human exposure doses to airborne PAHs. Further, the incremental lifetime cancer risk (ILCR) was calculated and it's found that ILCR from inhalation was higher than that from dermal uptake for children and adults in Beijing and Zhengzhou, while the ILCR for Xinxiang presented a contrary pattern, revealing dermal uptake to be an equally significant exposure pathway to airborne PAHs compared to inhalation.

Elevated expression of AhR and NLRP3 link polycyclic aromatic hydrocarbon exposure to cytokine storm in preschool children

BACKGROUND

Polycyclic aromatic hydrocarbons (PAHs), as a group of persistent organic pollutants, are linked to impaired immune function and low-grade inflammation in adults and children. However, the potential of PAHs to lead to a cytokine storm associated with AhR (aryl hydrocarbon receptor) and NLRP3 (NLR family pyrin domain containing 3) in humans has been poorly studied.

OBJECTIVES

We aimed to investigate the associations between PAH exposure, AhR and NLRP3 expression, and cytokines associated with a cytokine storm in healthy preschoolers.

METHODS

Basic demographic surveys and physical examinations were conducted on 248 preschoolers from an electronic waste (e-waste) recycling area (Guiyu, n = 121) and a reference area (Haojiang, n = 127). Ten urinary PAH metabolite (OH-PAH) concentrations were measured. We also measured the expression levels of AhR and NLRP3 and seventeen serum cytokine levels.

RESULTS

The concentrations of multiple OH-PAHs were significantly higher in the exposed group than those in the reference group, especially 1-hydroxynaphthalene (1-OH-Nap) and 2-hydroxynaphthalene (2-OH-Nap). PAH exposure was closely related to a child's living environment and hygiene habits. Expression levels of AhR and NLRP3 were significantly higher in the exposed group than in the reference group. Similarly, serum IL-1β, IL-4, IL-5, IL-10, IL-12p70, IL-13, IL-17A, IL-18, IL-22, IL-23, and IFN-γ levels were notably higher in the e-waste-exposed children than in the reference children. After adjusting for age, gender, BMI, family income, parental education level, and second-hand smoke exposure, we found that increased PAH exposure was associated with higher AhR and NLRP3 expression and elevated IL-4, IL-10, IL-12p70, IL-18, IL-22, IL-23, TNF-α, and IFN-γ levels. The associations between PAH exposure and IL-1β, IL-18, IFN-γ, and TNF-β were mediated by NLRP3 expression, and the relationships between PAH exposure and IL-4, IL-10, IL-12p70, IL-22, IL-23, and TNF-α were mediated by AhR expression.

CONCLUSIONS

Our findings suggest that the association between PAH exposure and a cytokine storm may be mediated by AhR and NLRP3 expression among preschoolers.

The concentration of polycyclic aromatic hydrocarbons (PAHs) in the processed meat samples collected from Iran's market: a probabilistic health risk assessment study

The concentration of PAHs among raw and cooked meat products (sausages and burgers), randomly collected from five regions of Tehran, Iran, was investigated by the aid of a gas chromatography-mass spectrometry (GC-MS), and the risk assessment was conducted. The concentration of 16 types of PAHs in sausage and burger samples was found in the range of 8.08 to 29.55 and 10.18 to 29.85 μg/kg, respectively. The concentrations of some PAHs such as anthracene (A) (14.12 μg/kg) and acenaphthylene (Acl) (13.4 μg/kg) were higher than the European Standard (2 μg/kg). Among the meat products with different meat percentages (50, 70, and 90), the highest level of total PAHs was noted in the product containing 90% meat (19.34 μg/kg), while the highest mean level of PAHs was noted in fried meat products (23.31 μg/kg). A positive and significant correlation between cooking method and brand of product with the concentration of PAHs (p-value < 0.05) was noted. Also, no concern regarding the non-carcinogenic risk due to the ingestion of PAHs via consumption of the meat products was demonstrated by the health risk. However, the carcinogenic risk due to the consumption of sausage and burger was at the tolerable (1E-6 to 1E-4) and considerable (> 1E-4) risk levels, respectively. In this regard, further assessments to control and modify the cooking method among the Iranian population were recommended.