Seasonal toxicity of urban road dust in runoff process-studies in Poland.

Urban road dust (URD) is one of the most important non-point sources of pollution in agglomerations. The aim of this study was to assess the seasonal toxic effects of URD runoff in two regions of Poland. The concentrations of elements in URD and leachate were studied. The impact of pollutants in URD runoff on water organisms was evaluated using Daphtoxkit F and Rotoxkit F (LC50). The acute toxicity tests for crustaceans and rotifers were selected as the response of these taxa reflects the impact on zooplankton, a key component of aquatic ecosystem and the basis of most food webs. The concentrations of elements were found to vary depending on the site, although URD samples collected in Katowice agglomeration (Upper Silesia) had higher values of elements (Mn, Cu, Zn, As) compared to Wroclaw (Lower Silesia). The concentrations of Mn, Zn, As, Cr, and Mg in water-soluble fraction of URD were higher in summer and winter in the Upper Silesia region due to rainwater runoff resulting from traffic, industries, post-industrial waste, and the presence of old heating systems. When comparing the content of elements in the water-soluble fraction between seasons, Zn, As, Cr, and Al concentrations were slightly higher in winter. The highest mortality of Daphnia magna and Brachiouns calyciflorus was observed in URD from both agglomerations in winter. However, the mortality is likely due to the concentration of elements or/and the coexistence of an unknown compound or a synergistic effect of the studied elements. This study highlights the alarming seasonal sources of elements in URD runoff, which will directly enter the food chain and affect the entire ecosystem, and human health.

Off-gassing from firefighter suits (nomex) as an indoor source of BTEXS.

The clothes and special equipment of firefighters can be a source of indoor air pollution. Nevertheless, it has not been investigated so far what the scale of the release of various compounds from such materials into the indoor air can be. The following study analysed the results of an experiment involving the passive measurement of concentrations of selected compounds, i.a. benzene, toluene, ethylbenzene, m,p-xylene, o-xylene, styrene, isopropylbenzene and n-propylbenzene (BTEXS) in the air of a room where firefighters' special clothing, which had been previously exposed to emissions from simulated fires, was stored. The study included simulations of fires involving three materials: wood, processed wood (OSB/fibreboard) and a mixture of plastics. After being exposed to the simulated fire environment, special clothing (so-called nomex) was placed in a sealed chamber, where passive collection of BTEXS was carried out using tube-type axial passive samplers and a gas chromatograph. Irrespective of which burned material special clothing was exposed to, the compound emitted into the air most intensively was toluene. Its rate of release from a single nomex ranges from 4.4 to 28.6 µg h-1, while the corresponding rates for the sum of BTEXS are between 9.97 and 44.29 µg h-1.

Exploring the Relationship between Particulate Matter Emission and the Construction Material of Road Surface: Case Study of Highways and Motorways in Poland.

Road dust is an important inexhaustible source of particulate matter from traffic and the resuspension of finer particles carried by wind and traffic. The components of this material are of both natural and anthropogenic origin. Sources of particulate pollution are vehicles and road infrastructure. The work aimed to analyze the mass fraction of the finest fractions of road dust (<0.1 mm) collected from highways and expressways with asphalt and concrete surfaces. Sampling points were located in the central and southern parts of Poland. The research material was sieved on a sieve shaker. It has been proven that concrete pavement is less susceptible to abrasion than asphalt pavement. Particles formed under the influence of the erosion of asphalt and concrete belong to the fraction gathering coarser particles than the critical for this research fraction (<0.1 mm). It was found that limiting the area with sound-absorbing screens leads to the accumulation of fine road dust in this place, contrary to the space where are strong air drafts that remove smaller particles from the vicinity of the road. In general, the mass fraction of particles smaller than 100 µm in road dust was from 12.8% to 3.4% for asphalt surfaces and from 12.0% to 6.5% for concrete surfaces.

Is Poland at risk of urban road dust? Comparison studies on mutagenicity of dust.

Depopulation concerns many polish cities, with the exception of a few metropolises such as Wroclaw (Lower Silesia) and Katowice (Upper Silesia) where investments are growing and therefore more humans are exposed to urban environmental pollution. Accumulation of toxic substances on road surfaces is a major global challenge requiring methods of assessing risk that initiate the proper management strategies. In this study urban road dust (URD) has been collected at seventeen sites in Lower and Upper Silesia regions in Poland renowned for their elevated level of pollution. The aim of the study was: (i) to determine PAH concentration in URD in both regions with the identification of their possible sources based on diagnostic ratio; (ii) to assess possible mutagenic effects of URD with the application of Ames test (Salmonella assay); (iii) to define a possible carcinogenic risk related to URD in both studied regions. We found that the total PAH content of collected URD samples ranged from 142.4 to 1349.4 ng g-1. The diagnostic ratio of PAHs in URD for all studied sites showed that pyrogenic combustion predominated indicating traffic-related and biomass sources of pollution. The Ames assay, which has never been used in studies of URD in Poland, demonstrated that in both regions, URD samples (from eight sites), were characterised by the highest mutagenicity values. Additionally, Incremental Lifetime Cancer Risk (ILCR) values, based on PAH content only, were between 10 and 6 to 10-4 indicating potential risk of cancer. Reassuming, humans in both agglomerations are exposed to factors or compounds with carcinogenic properties which may have an adverse health effect through the urban road dust mainly due to vehicular traffic, heating systems and industrial activities.

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

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

Particulate Matter Concentration in Selected Facilities as an Indicator of Exposure to Their Service Activities.

In recent years, the correlation between the concentration of pollutants in the atmosphere and inside buildings has been reported as high. The air inside living quarters and public utility buildings or the interiors of public transport vehicles, as well as the relationship between the internal and external sources of particulate matter (PM) and gaseous pollutants, have underwent sufficient research. On the other hand, non-production rooms, i.e., offices, restaurants, beauty salons, etc. remain very poorly recognized in this respect. For the above reasons, the aim of this work is to determine the difference in the total dust (TSP) and respirable PM (PM4) concentrations in selected rooms, i.e., offices and beauty centers, in relation to their outdoor concentrations. They were measured at six locations in accordance with the standard for the conditions at workplaces by means of PM aspirators. Indoor concentrations of TSP and PM4 were much higher than those in the external surroundings of the facilities. There were no significant relationships between the TSP and PM4 concentrations inside and outside tested rooms. Although the characteristic of the internal PM essentially depends on the characteristics of the external PM migrating to the interior of the premises, considering some types of non-production premises, internal emissions fundamentally changed the characteristics of PM.

The Level of Fear in the Polish Police Population during the COVID-19 Pandemic with the Impact of Sociodemographic Variables.

This study has a twofold objective. First, we aim to measure the levels of fear among Polish police officers using the COVID-19 Fear Scale (FCV-19S) that has a stable unidimensional structure allowing for the provision of additional data by combining variables. This structure allows the second objective to be met to measure the correlation with sociodemographic variables. The utilitarian objective of the study is to provide information for updating support policies for stress management in the service. The questionnaire was completed by 1862 people with a mean age of 38.75 years with a good Cronbach's alpha (0.89). The perceived level of fear associated with COVID-19 should be considered relatively low. Caring for the elderly does not affect the level of fear. The factors of gender, age and having children statistically significantly differentiate the perceptions of fear. Therefore, there is a necessity to focus on building support for police officers who are over 50 years old, as well as for women, where higher levels of fear in both men and women can translate into the development of psychosomatic illnesses.

New insights into submicron particles impact on visibility.

The aim of the study was to analyze the impact of very fine atmospheric particles (submicron particulate matter; PM1) on visibility deterioration. Taking into consideration not only their entirely different physio-chemical properties in comparison to a well-recognized PM10 but also the origin and a growing environmental awareness of PM1, the main research problem has been solved in few steps. At first, the chemical composition of PM1 was determined in two selected urban areas in Poland. Measurements of meteorological parameters, i.e., air temperature and humidity, precipitation, atmospheric pressure, wind speed, and visibility, were also conducted. The next step of the work was the analysis of (1) seasonal changes of the concentration of PM1 and its main components, (2) the influence of chemical components of PM1 on light extinction, and (3) the influence of PM1 and humidity on visibility. Hierarchical cluster analysis, correlation matrixes and a heat map, and classification and regression tree analysis were used. The light extinction coefficient is influenced mainly by coarse mass of PM, and PM1-bound ammonium nitrate, organic matter, and by Rayleigh scattering. The less important in the light extinction coefficient shaping has PM1-bound ammonium sulfate, elemental carbon, and soil. In this way, the secondary origin PM1 components were proved to most significantly influence the visibility. The obtained results confirmed the possibility of the use of statistical agglomeration techniques to identify ranges of variation of visibility, including independent variables adopted to analyses (meteorological conditions, chemical composition of PM1, etc.).

Properties of Particulate Matter in the Air of the Wieliczka Salt Mine and Related Health Benefits for Tourists.

This study aimed to evaluate the mass concentration of size-resolved (PM1, PM2.5, PM4, PM10, PM100) particulate matter (PM) in the Wieliczka Salt Mine located in southern Poland, compare them with the concentrations of the same PM fractions in the atmospheric air, and estimate the dose of dry salt aerosol inhaled by the mine visitors. Measurements were conducted for 2 h a day, simultaneously inside (tourist route, passage to the health resort, health resort) and outside the mine (duty-room), for three days in the summer of 2017 using DustTrak DRX devices (optical method). The highest average PM concentrations were recorded on the tourist route (54-81 µg/m3), while the lowest was in the passage to the health resort (49-62 µg/m3). At the same time, the mean outdoor PM concentrations were 14-20 µg/m3. Fine particles constituting the majority of PM mass (68-80%) in the mine originated from internal sources, while the presence of coarse particles was associated with tourist traffic. High PM deposition factors in the respiratory tract of children and adults estimated for particular mine chambers (0.58-0.70), the predominance of respirable particles in PM mass, and the high content of NaCl in PM composition indicate high health benefits for mine visitors.

Site environment type - The main factor of urban road dust toxicity?

The main objective of the study was to determine the effects of the water extracts of urban road dust (URD) samples on the growth inhibition and mortality rate of Heterocypris incongruens in various site environment type. We collected 24 samples of the road dust close to highways, main roads, crossroads as well as at other places i.e. residential area, and suburbs. We determined the selected metals (Al, As, Ba, Cd, Co, Cr, Cu, Ga, Mg, Mn, Mo, Ni, Pb, Rb, Sr, Ti, Tl, V and Zn) content of the water extracts of these samples as well as we tested the toxicity of the water extracts of URD samples using a commercial test Ostracodtoxkit F. We observed the lowest values of the growth inhibition of H. incongruens for residential areas and suburbs (<50%). The highest growth inhibition we found for water extracts of URD samples collected at the main roads in the Katowice urban area and crossroads in the urban areas. Although the mortality and growth inhibition of H. incongruens were related to the road traffic emissions it was impossible to clearly relate this finding with the urban site category.

Contribution of landfill fires to air pollution - An assessment methodology.

We investigated the contribution of waste fires to air pollution. The annual emission of pollutants (CO, NOx, PM10, SO2) and greenhouse gases (CH4, CO2) were evaluated. The prediction of emissions is based on statistical data from 79 large fires that took place in Poland in 2018. We analyzed the spatial distribution of these fires along with the expected emission factor. The predicted emissions from all large waste fires was in total: 2.05 ± 0.10Gg of CH4, 19.60 ± 0.90Gg of CO, 196 ± 13Gg of CO2, 0.963 ± 0.047Gg of NOx, 5.26 ± 0.58Gg of PM10, and 0.72 ± 0.12Gg of SO2. For the evaluation of the consequences, we used the number of people exposed to PM10 emitted in one very big fire. Almost 6.5 million people were exposed to an additional 1-hour average concentration of PM10 higher than 10 µg/m3 and over 360 thousand were exposed to a concentration higher than 100 µg/m3.

Characteristics of Particles Emitted from Waste Fires-A Construction Materials Case Study.

This study aimed to determine the relative densities of populations of particles emitted in fire experiments of selected materials through direct measurement and parametrization of size distribution as number (NSD), volume (VSD), and mass (MSD). As objects of investigation, four typical materials used in construction and furniture were chosen: pinewood (PINE), laminated particle board (LPB), polyurethane (PUR), and poly(methyl methacrylate) (PMMA). The NSD and VSD were measured using an electric low-pressure impactor, while MSD was measured by weighing filters from the impactor using a microbalance. The parametrization of distributions was made assuming that each distribution can be expressed as the sum of an arbitrary number of log-normal distributions. In all materials, except PINE, the distributions of the particles emitted in fire experiments were the sum of two log-normal distributions; in PINE, the distribution was accounted for by only one log-normal distribution. The parametrization facilitated the determination of volume and mass abundances, and therefore, the relative density. The VSDs of particles generated in PINE, LPB, and PUR fires have similar location parameters, with a median volume diameter of 0.2-0.3 µm, whereas that of particles generated during PMMA burning is 0.7 µm. To validate the presented method, we burned samples made of the four materials in similar proportions and compared the measured VSD with the VSD predicted based on the weighted sum of VSD of raw materials. The measured VSD shifted toward smaller diameters than the predicted ones due to thermal decomposition at higher temperatures.

Mutagenicity of indoor air pollutants adsorbed on spider webs.

In this study, air pollutants were determined on spider webs collected from six indoor sites in the Lower Silesia region, southwest Poland. In order to assess the mutagenicity (M) of the collected samples, the standard Salmonella assay was used with two Salmonella typhimurium strains, TA98 and YG1041. The assays were conducted with and without metabolic activation (S9 mix). The presence of 15 polycyclic aromatic hydrocarbons (PAHs) and PAH-derivatives (nitro-PAHs; NPAHs) on spider webs was also assessed at the studied sites. The total PAH content of collected samples ranged from 1.65 to 51.75 µg g-1; the total NPAH content ranged from 0.22 to 2.44 µg g-1. The highest PAH concentration was found at two sites: a basement with coal heating (S4) and a garage (S6). Samples from these two sites were also characterized by the highest mutagenicity values in TA98 strain (65,127 and 35,565 revertants/g of web in the absence and presence of S9 mix, respectively, for S4 and 54,753 and 46,262 revertants/g, respectively, for S6). For strain YG1041, the highest values were obtained in a basement with coal heating; values were 233,748 and 185,321 revertants/g of web in the absence and presence of S9 mix, respectively. The concentration of PAHs was significantly correlated with the mutagenicity (M) of the web samples collected. Reassuming, people are exposed to substances with possible carcinogenic properties and potential adverse health effect through the ambient air due to vehicular traffic, heating systems, cooking habits etc. The application of spider webs sampling could bring the very important information regarding the possible health effect associated with indoor air, making these kind of studies cheap and reliable.

Monitoring of indoor polycyclic aromatic hydrocarbons using spider webs.

Fifteen polycyclic aromatic hydrocarbons (PAHs) were measured in the spider webs prepared in the laboratory and exposed to indoor air pollution in a defined period of time. We have selected homes differing in location (rural area vs. city), type of room (living room, kitchen, basement), inhabitants' habits (smoking cigarettes vs. non-smoking) and type of heating/cooking devices used (natural gas, liquefied gas, coal- and wood-fuelled heating). Webs from two species, from Agelenidae and Pholcidae families, were prepared and used for monitoring of PAHs. PAHs were characterised based on concentration, profile distribution, source apportionment by cluster analysis and diagnostic ratios. The concentrations of sum of 15 PAHs (µg g-1 dry weight) varied from 1.7 (bedroom in detached house in rural area) to 67.9 µg g-1 (room with heavy smokers in detached house in the city), and were dominated by 3-ring (6.89-57.1%) and 2-ring compounds (5.05-48.3%). The result of cluster analysis (CA) suggested two distinct groups of PAHs. The dominant PAH source was found to be mixed petrogenic and pyrogenic consisting of a mixture of cooking, smoking, heating and neighbouring traffic activities.

Submicron particle-bound polycyclic aromatic hydrocarbons in the Polish teaching rooms: Concentrations, origin and health hazard.

The goal of the work was to investigate the concentrations of the 16 US EPA priority polycyclic aromatic hydrocarbons (PAH) bound to submicrometer particles (particulate matter, PM1) suspended in the air of university teaching rooms and in the atmospheric air outside. Two teaching rooms were selected in two Polish cities, Gliwice, southern Poland, and Warsaw, central Poland, differing with regard to the ambient concentrations and major sources of PM and PAH. The variabilities of indoor and outdoor 24-hr concentrations of PM1-bound PAH, the ratio (I/O) of the indoor to outdoor 24-hr concentrations of PM1-bound PAH, probable sources of PAH and the level of the hazard from the mixture of the 16 PAH (ΣPAH) to humans at both sites were analyzed. In both Warsaw and Gliwice, the mean concentrations of PM1-bound ΣPAH were slightly higher in the atmospheric air than in the rooms. The indoor and outdoor concentrations of individual PAH in Gliwice were correlated, in Warsaw - they were not. Most probably, the lack of the correlations in Warsaw was due to the existence of an unidentified indoor source of gaseous PAH enriching PM1 in phenanthrene, fluorene, and pyrene. Although the ambient concentrations of PM1-bound PAH were low compared to the ones observed earlier at both sites, they were much higher than in other urbanized European areas. However, because of low mass share of heavy PAH in ΣPAH, the various indicators of the health hazard from the 16 PAH mixture were low compared to other regions.

PM Origin or Exposure Duration? Health Hazards from PM-Bound Mercury and PM-Bound PAHs among Students and Lecturers.

This study assessed inhalation exposure to particulate matter (PM1)-bound mercury (Hgp) and PM1-bound polycyclic aromatic hydrocarbons (PAHs) among university students. For this purpose, simultaneous indoor (I) and outdoor (O) measurements were taken from two Polish technical universities (in Gliwice and Warsaw) located in distinct areas with respect to ambient concentrations and major sources of PM. The indoor geometric mean concentrations of Hgp were found to be 1.46 pg·m-3 and 6.38 pg·m-3 in Warsaw and Gliwice, while the corresponding outdoor concentrations were slightly lower at 1.38 pg·m-3 and 3.03 pg·m-3, respectively. A distinct pattern was found with respect to PAH concentrations with estimated I/O values of 22.2 ng·m-3/22.5 ng·m-3 in Gliwice and 10.9 ng·m-3/11.12 ng·m-3 in Warsaw. Hazard quotients (HQs) as a result of exposure to Hgp for students aged 21 ranged from 3.47 × 10-5 (Warsaw) to 1.3 × 10-4 (Gliwice) in terms of reasonable maximum exposure (RME). The non-cancer human health risk value related to Hgp exposure was thus found to be below the acceptable risk level value of 1.0 given by the US EPA. Daily exposure values for lecture hall occupants, adjusted to the benzo(a)pyrene (BaP) toxicity equivalent (BaPeq), were 2.9 and 1.02 ng·m-3 for the Gliwice and Warsaw students, respectively. The incremental lifetime cancer risk (ILCR) values with respect to exposure to PM1-bound PAHs during the students' time of study were 5.49 × 10-8 (Warsaw) and 1.43 × 10-7 (Gliwice). Thus, students' exposure to indoor PAHs does not lead to increased risk of lung cancer.

Health Risk Impacts of Exposure to Airborne Metals and Benzo(a)Pyrene during Episodes of High PM10 Concentrations in Poland.

OBJECTIVE: To check whether health risk impacts of exposure to airborne metals and Benzo(a) Pyrene during episodes of high PM10 concentrations lead to an increased number of lung cancer cases in Poland. METHODS: In this work, we gathered data from 2002 to 2014 concerning the ambient concentrations of PM10 and PM10-bound carcinogenic Benzo(a)pyrene [B(a)P] and As, Cd, Pb, and Ni. With the use of the criterion of the exceedance in the daily PM10 mass concentration on at least 50% of all the analyzed stations, the PM10 maxima's were selected. Lung cancer occurrences in periods with and without the episodes were further compared. RESULTS: During a 12-year period, 348 large-scale smog episodes occurred in Poland. A total of 307 of these episodes occurred in the winter season, which is characterized by increased emissions from residential heating. The occurrence of episodes significantly (P < 0.05) increased the concentrations of PM10-bound carcinogenic As, Cd, Pb, Ni, and B(a)P. During these events, a significant increase in the overall health risk from those PM10-related compounds was also observed. The highest probability of lung cancer occurrences was found in cities, and the smallest probability was found in the remaining areas outside the cities and agglomerations. CONCLUSION: The link between PM pollution and cancer risk in Poland is a serious public health threat that needs further investigation.

Magnetic susceptibility of spider webs as a proxy of airborne metal pollution.

The purpose of this pilot study was to test spider webs as a fast tool for magnetic biomonitoring of air pollution. The study involved the investigation of webs made by four types of spiders: Pholcus phalangioides (Pholcidae), Eratigena atrica and Agelena labirynthica (Agelenidae) and Linyphia triangularis (Linyphiidae). These webs were obtained from outdoor and indoor study sites. Compared to the clean reference webs, an increase was observed in the values of magnetic susceptibility in the webs sampled from both indoor and outdoor sites, which indicates contamination by anthropogenically produced pollution particles that contain ferrimagnetic iron minerals. This pilot study has demonstrated that spider webs are able to capture particulate matter in a manner that is equivalent to flora-based bioindicators applied to date (such as mosses, lichens, leaves). They also have additional advantages; for example, they can be generated in isolated clean habitats, and exposure can be monitored in indoor and outdoor locations, at any height and for any period of time. Moreover, webs are ubiquitous in an anthropogenic, heavily polluted environment, and they can be exposed throughout the year. As spider webs accumulate pollutants to which humans are exposed, they become a reliable source of information about the quality of the environment. Therefore, spider webs are recommended for magnetic biomonitoring of airborne pollution and for the assessment of the environment because they are non-destructive, low-cost, sensitive and efficient.

Inhalation Exposure to PM-Bound Polycyclic Aromatic Hydrocarbons Released from Barbecue Grills Powered by Gas, Lump Charcoal, and Charcoal Briquettes.

The present study seeks to define the possible cancer risk arising from the inhalation exposure to particle (PM)-bound polycyclic aromatic hydrocarbons (PAHs) present in barbecue emission gases and to compare the risk depending on the type of fuel used for grill powering. Three types of fuel were compared: liquid propane gas, lump charcoal, and charcoal briquettes. PM2.5 and PM2.5-100 were collected during grilling. Subsequently, 16 PAHs congeners were extracted from the PM samples and measured quantitatively using gas chromatography. The content of PM-bound PAHs was used to calculate PAHs deposition in the respiratory tract using the multiple path particle dosimetry model. Finally, a probabilistic risk model was developed to assess the incremental lifetime cancer risk (ILCR) faced by people exposed to PAHs. We found a distinctly greater PAHs formation in case of grills powered by charcoal briquettes. The summary concentration of PAHs (Σ16PAH) ranged from <0.002 µg/m3 (gas grill) to 21.52 µg/m3 (grill powered by briquettes). Daily exposure of a grill operator, while grilling meat, to PM2.5-bound PAHs, adjusted to benzo[a]pyrene toxicity equivalent (BaPeq), was 326.9, 401.6, and 0.04 ng/d for lump charcoal, charcoal briquettes, and gas powered grill, respectively. Exposure to PAHs emitted from charcoal briquettes was four orders of magnitude greater than that for gas grill. The ILCR followed a log-normal distribution, with a geometric mean of 8.38 × 10-5 for exposure to PM2.5-bound PAHs emitted from gas grills unloaded with food and as high as 8.68 × 10-1 for the grills loaded with food over charcoal briquettes. The estimated cancer risk for people who would inhale barbecue particles for 5 h a day, 40 days a year exceeds the acceptable level set by the U.S. Environmental Protection Agency. We conclude that the type of heat source used for grilling influences the PM-bound PAHs formation. The greatest concentration of PAHs is generated when grilling over charcoal briquettes. Loading grills with food generates conspicuously more PAHs emissions. Traditional grilling poses cancer risk much above the acceptable limit, as opposed to much less risk involving gas powered grills.