Benzo[a]pyrene Equivalents Research Articles

Determination of Polycyclic Aromatic Hydrocarbon Content in Garden Herbal Plants Using Liquid Chromatographic Analysis (HPLC-FL).

Polycyclic aromatic hydrocarbons (PAHs) are a group of chemical compounds generated as a result of the incomplete combustion of fossil fuels or wood. PAHs are known for their negative effect on living organisms, including teratogenic, carcinogenic and mutagenic activity. The objective of this study is to determine the contamination of three popular herbal species showing pro-health properties, i.e., lavender, parsley and mint, with polycyclic aromatic hydrocarbons, collected from three different backyard gardens in Poland. The concentration of PAHs in plant material was determined by high-performance liquid chromatography with a fluorescence detector (HPLC-FL). The concentration of eleven PAHs in plant material was determined with high-pressure liquid chromatography after extraction using the QuEChERS purification technique. Mint collected within an area of a mining and energy production complex (the city of Konin) was characterized by the highest Σ of 11 PAHs, equaled to 902.35 µg/g FW, with anthracene being the most abundant compound. However, it contained the lowest sum of PAHs, among all tested plants, with high carcinogenicity. Parsley from the city of Poznań showed the highest content of benzo[a]pyrene (BaP), showing the strongest carcinogenicity, while the highest value of BaP equivalent was calculated for mint collected in Konin. The obtained results suggest that the level and profile of plant contamination with PAHs depend on the species and the location of herb cultivation. In particular, mining and energy industry facilities are sources of PAHs, which contaminate plant material for further direct use or as bioactive herbal extracts.

Sedimentary records of polycyclic aromatic hydrocarbons from three enclosed lakes in China: Response to energy structure and economic development

Historical polycyclic aromatic hydrocarbon (PAH) pollution was explored through the sedimentary records of three lakes: Huguangyan Maar Lake (HGY) in South China, Mayinghai Lake (MYH) in North China, and Sihailongwan Lake (SHLW) in Northeast China. In these three lakes, the PAH concentrations in sediments are still rising, showing the different trend to lakes in developed countries. PAH pollution in South China occurred from 1850, much earlier than the increases since 1980 observed in North and Northeast China. The temporal trends of PAH concentrations in lake sediments are highly correlated with local economic development. Spatially, although the region where HGY is located has the highest gross domestic product, higher fluxes of PAHs were found in MYH sediments, indicating that atmospheric PAH pollution in North China might be more serious, and that PAH pollution is not fully correlated with economic development. Source analysis suggested that the PAHs in lake sediments are mainly derived from oil leaks, coal and biomass combustion, vehicle emissions, and diagenesis. Positive matrix factorization (PMF) model revealed that the contribution of vehicle emissions and coal combustion to PAHs has increased significantly in the past 40 years. Benzo(a)pyrene equivalent (BaPE) in the surface sediments of MYH and SHLW were similar and higher than in HGY. In HGY, vehicle emissions posed the highest toxic risk, followed by coal combustion. However, in MYH, the toxicity risk of vehicle emissions was close to that of coal and biomass combustion due to the highly developed coal industry in Shanxi Province. In SHLW, the contribution of fossil fuel combustion to BaPE was significantly higher than that of biomass combustion. This study provides important information for understanding PAH pollution affected by anthropogenic activities in the Anthropocene and provides a scientific basis for formulating PAH pollution control strategies.

Cryoconites as biogeochemical markers of anthropogenic impact in high mountain regions: analysis of polyaromatic pollutants in soil-like bodies

The globalisation and omnidirectional character of anthropogenic processes has challenged scientists around the world to estimate the harmful effects of these processes on ecosystems and human health. Polycyclic aromatic hydrocarbons (PAHs) is one the most infamous group of contaminants, originated both from natural and anthropogenic processes. They could transport to high latitudes and altitudes through atmospheric long-distance transfer and further enter ecosystems of these vulnerable regions by deposition on terrestrial surfaces. An interesting object for tracking transboundary contamination processes in high mountain ecosystems is called cryoconite. Cryoconite, a dark-coloured supraglacial sediment which is abundant in polar and mountain environments, is considered as a storage of various pollutants, including PAHs. Thus, it may pose a risk for local human health and ecosystem through short-distance transfer. Studied cryoconite sediments were collected at the surface of Skhelda and Garabashi glaciers, Central Caucasus high-mountain region, as well as mudflow, moraine material and local soils at the Baksan Gorge in order to examine levels of their contamination. We analysed the content of 15 priority polyaromatic compounds from the US EPA list and used the method of calculation of PAHs isomer ratios with the purpose of identifying their source. To estimate their potential toxicity, Benzo[a]pyrene (BaP) equivalents were calculated. Maximum concentration was defined for NAP (84 ng×g-1), PHE (40 ng×g-1) and PYR (47 ng×g-1), with the minimum concentration for ANT (about 1 ng×g-1). The most polluted material is a cryoconite from Garabashi glacier because of local anthropogenic activities and long-distance transfer. High-molecular weight PAHs are dominated in PAHs composition of almost all samples. The most common sources of PAHs in studied materials are combustion processes and mixed pyrolytic/petrogenic origin. Toxicity levels of separate PAHs did not exceed the maximum permissible threshold concentrations values in most cases. However, the sum of PAHs in BaP equivalents exceed the threshold values in all samples, in some of them more than twice.

Polycyclic aromatic hydrocarbons in airborne particulate matter samples from Hanoi, Vietnam: Particle size distribution, aryl hydrocarbon ligand receptor activity, and implication for cancer risk assessment

Concentrations and profiles of unsubstituted and methylated polycyclic aromatic hydrocarbons (PAHs and Me-PAHs) were analyzed in airborne particulate matter (PM) samples collected from high-traffic roads in Hanoi urban area. Levels of PAHs and Me-PAHs ranged from 210 to 660 (average 420) ng/m3 in total PM, and these pollutants were mainly associated with fine particles (PM2.5) rather than coarser ones (PM > 10 and PM10). Proportions of high-molecular-weight compounds (i.e., 5- and 6-ring) increased with decreasing particle size. Benzo[b+k]fluoranthene, indeno[1,2,3-cd]pyrene, and benzo[ghi]perylene were the most predominant compounds in the PM2.5 samples. In all the samples, Me-PAHs were less abundant than unsubstituted PAHs. The PAH-CALUX assays were applied to evaluate aryl hydrocarbon receptor (AhR) ligand activities in crude extracts and different fractions from the PM samples. Benzo[a]pyrene equivalents (BaP-EQs) derived by the PAH-CALUX assays for low polar fractions (mainly PAHs and Me-PAHs) ranged from 300 to 840 ng/m3, which were more consistent with theoretical values derived by using PAH-CALUX relative potencies (270–710 ng/m3) rather than conventional toxic equivalency factor-based values (22–69 ng/m3). Concentrations of PAHs and Me-PAHs highly correlated with bioassay-derived BaP-EQs. AhR-mediated activities of more polar compounds and interaction effects between PAH-related compounds were observed. By using PAH-CALUX BaP-EQs, the ILCR values ranged from 1.0 × 10−4 to 2.8 × 10−4 for adults and from 6.4 × 10−5 to 1.8 × 10−4 for children. Underestimation of cancer risk can be eliminated by using effect-directed method (e.g., PAH-CALUX) rather than chemical-specific approach.

Polycyclic Aromatic Hydrocarbons and Potentially Toxic Elements in Soils of the Vicinity of the Bulgarian Antarctic Station “St. Kliment Ohridski” (Antarctic Peninsula)

The investigation conducted was dialed to quantitative and qualitative evaluation of 15 priority polycyclic aromatic hydrocarbons (PAHs) and Potentially Toxic Elements (Cu, Pb, Zn, Cd, Ni, and Cr) is soils and cryoconites on “St. Kliment Ohridski” Antarctic station territory and its vicinities. Estimation of benzo(a)pyrene (BaP)–equivalents, PAHs and different PAHs isomer pair ratios were used for identification of general toxicity, nature and origin of individual PAHs and their groups. Total concentrations of PAHs in BaP–equivalents showed, that ∑15PAH of all selected points was higher than the threshold concentration (20 μg × kg−1–Russian environmental legislation) for benzo(a)pyrene. Different PAHs isomer ratios showed the natural (petrogenic) source of PAHs at all soils examples (except Cryosol Toxic Transportic). The maximum content among potentially toxic elements was recorded for Zn (75.7 mg × kg−1 at L26), the minimum for Cd (0.201 mg × kg−1 at L1A). Average concentrations of potentially toxic elements are generally lower compared to the results of previous studies. Application of Igeo index, characterizes the majority of the studied soils as unpolluted or practically unpolluted. Data obtained indicates that there is no current critical anthropogenic load on the environmental components of the landscapes investigated.

Polyurethane foam-based passive air sampling for simultaneous determination of POP- and PAH-related compounds: A case study in informal waste processing and urban areas, northern Vietnam

Polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), hexabromobiphenyl (BB-153), novel brominated flame retardants (NBFRs), and unsubstituted/methylated polycyclic aromatic hydrocarbons (PAHs/Me-PAHs) were simultaneously monitored in the air samples collected from Vietnamese urban and vehicular waste processing areas by using polyurethane foam-based passive air sampling (PUF–PAS) method. Concentrations (pg m−3) of organic pollutants decreased in the order: PAHs (median 29,000; range 5100–100,000) > Me-PAHs (6000; 1000–33,000) > PCBs (480; 170–1100) > PBDEs (11; 5.3–86) > NBFRs (0.20; n. d. – 51) > BB-153 (n.d.). The difference in total PCB and PBDE concentrations between the urban and waste processing air samples was not statistically significant. Meanwhile, levels of PAHs, Me-PAHs, benzo [a]pyrene equivalents (BaP-EQs), and toxic equivalents of dioxin-like PCBs (WHO-TEQs) were much higher in the waste processing sites. This is the first report on the abundance of mono- and di-CBs (notably CB-11) in the air from a developing country, suggesting their roles as emerging and ubiquitous air pollutants. Our results have indicated potential sources of specific organic pollutants such as dioxin-like PCBs, PAHs, and Me-PAHs from improper treatment of end-of-life vehicles and other vehicle related materials (e.g., waste oils and rubber tires), as well as current emission of PCBs and PBDEs in the urban area in Vietnam. Further atmospheric monitoring studies should be conducted in this developing country that cover both legacy and emerging contaminants with a focus on areas affected by rapid urbanization and informal waste processing activities.

Quantification, source apportionment and risk assessment of polycyclic aromatic hydrocarbons in sediments from Mokolo and Blood Rivers in Limpopo Province, South Africa

The presence of polycyclic aromatic hydrocarbons (PAHs) in the environment is of major concern since some of these compounds are highly persistent, toxic (causing cancer) and wide spread pollutants. The objective of this study was to evaluate the levels of PAHs in sediment samples collected from Blood and Mokolo Rivers in Limpopo Province, South Africa. The PAHs in sediments were extracted using optimized microwave-assisted extraction (MAE) method. The quantification of sixteen (16) PAHs in sediments was done by gas chromatography-flame ionization detector (GC-FID). The levels of PAHs recorded in sediment samples from Blood River ranged between 0.015 and 3.25 mg kg−1. The concentrations of PAHs obtained in sediments from Mokolo River (0.047 to 52.7 mg kg−1) were higher than those recorded in sediments from Blood River. The PAHs ratios indicated that both pyrogenic and petrogenic could be the sources of these compounds in both rivers. Toxic equivalency factors (TEFs) and benzo(a)pyrene equivalent (BaPE) were used to estimate the potential human health risk of PAHs in quantitative terms. The assessment of ecotoxicological risk indicated that the sediment samples collected from Mokolo River are at high toxicity risk while sediments from Blood River are at low sediment toxicity risk.

A comparative chemical study of PM10 in three Latin American cities: Lima, Medellín, and São Paulo

The study was part of the South American Emissions, Megacities and Climate Project (SAEMC). The objective was to identify and quantify organic and elemental carbon (OC and EC), monosaccharides, polycyclic aromatic hydrocarbons (PAHs), oxy and nitro-PAHs, water-soluble ions (WSI), and elements in particulate matter collected in intensive campaigns during a period (June, 2010) in Sao Paulo (Brazil), Lima (Peru), and Medellin (Colombia). PM10 concentration was higher in Sao Paulo than in the other two sites and 75% of the samples had concentrations above the World Health Organization (WHO) guideline. High concentrations of levoglucosan, a biomass burning tracer, highlighted the importance of this source in the Brazilian megacity. Levoglucosan-to-mannosan ratios for Sao Paulo suggested sugarcane burning, which in 2010 occurred in 70% of the state municipalities during harvest. Vehicular-related elements (Fe and Cu) had higher concentrations in Sao Paulo. As and Pb in Medellin were attributed to industrial emissions. Ni in Lima was associated with emissions from metal smelting facilities and ship heavy oil combustion. Higher total PAH concentrations and benzo[a]pyrene equivalent (BaPE) index in Sao Paulo indicated a stronger influence of vehicular exhaust in this megacity. The results highlighted the importance of biomass burning and vehicular sources for Sao Paulo, vehicular exhaust, biomass burning, and industrial sources for Medellin, and marine aerosol, together with vehicular, industrial, and ship exhaust, for Lima.

Emerging and legacy PAHs in urban soils of four small cities: Concentrations, distribution, and sources

Polycyclic aromatic hydrocarbons (PAHs) are widespread organic contaminants in the environment, much being accumulated in soils. Although their concentrations in large cities have been studied, their levels in small cities were less studied. This study determined the concentrations, distributions, and sources of 16 USEPA priority PAHs (legacy PAHs) and 6 emerging PAHs in urban soils of four small cities. A total of 100 soil samples were collected in Florida, USA. The average ∑16-PAHs in urban soils of Clay county, Ocala, Pensacola, and West Palm Beach were 1821, 2748, 3115 and 4055 μg kg−1, respectively. Based on benzo[a]pyrene-equivalent (BaP-EQ), the 7 USEPA carcinogenic PAHs (7cPAHs) and 3 emerging carcinogenic PAHs (3cPAHs) in urban soils in Clay County averaged 223 and 3703, Ocala 319 and 4521, Pensacola 302 and 5423, and West Palm Beach 449 and 5916 μg kg−1, respectively. Although ∑7cPAHs in 87–89% of samples were lower than the Florida Soil Cleanup Target Levels (FSCTLs) for industrial sites at 700 μg kg−1, ∑3cPAHs were 13–18 times greater than ∑7cPAHs. Based on the PMF model and molecular diagnostic ratios, soil PAHs were dominated by similar sources in small cities, mainly from pyrogenic sources including biomass, coal and coke combustion and vehicle emissions. It is important to evaluate both legacy and emerging PAHs concentrations in urban soils when considering soil remediation and human health risk assessment.

PAHs in urban soils of two Florida cities: Background concentrations, distribution, and sources

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous organic contaminants, which are found in soils throughout the U.S. The objective of this study was to determine the background concentrations, distributions, and sources of 16 USEPA priority PAHs in two urban soils. A total of 114 soil samples were collected from two large cities in Florida: Orlando and Tampa. The results showed that soils were dominated by high molecular weight PAHs in both cities. The average ∑16-PAHs in Orlando and Tampa soils were 3227 and 4562 μg kg−1, respectively. The averages of 7 carcinogenic PAHs based on the benzo[a]pyrene-equivalent (BaP-EQ) concentrations in the two cities were 452 and 802 μg kg−1. BaP-EQ concentrations in 60–62% of samples were higher than the Florida Soil Cleanup Target Level (FSCTL) for residential soils at 100 μg kg−1 and 20–25% of samples were higher than FSCTL for industrial soils at 700 μg kg−1. Based on molecular diagnostic ratios and PMF modeling, major sources of soil PAHs in both cities were similar, mainly from pyrogenic sources including vehicle emissions, and biomass and coal combustion. Based on ArcGIS mapping, PAH concentrations in soils near business districts and high traffic roads were higher. Thus, it is important to consider background PAH concentrations in urban soils when considering soil remediation.

Polycyclic Aromatic Hydrocarbons (PAHs) Associated with PM2.5 in Guadalajara, Mexico: Environmental Levels, Health Risks and Possible Sources

PM2.5 samples were collected from January 2009 to January 2010 at two sampling sites located in the downtown (Centro) and toward the southwest (Miravalle) in the city of Guadalajara, Mexico. The environmental concentrations of 14 selected polycyclic aromatic hydrocarbons (PAHs) in PM2.5 were identified and quantified. The most abundant PAHs in PM2.5 samples were benzo[ghi]perylene, indeno[1,2,3-cd]pyrene, benzo[b]fluoranthene, benzo[a]pyrene and benzo[k]fluoranthene, accounting for approximately 75% of the total PAHs. The total PAH concentrations at the two sampling sites ranged from 0.65 to 19.62 ng·m−3. Spatial variations were found during the dry-warm season, which were attributed mainly to differing intensities of local traffic and less dispersion of air pollutants in Miravalle. Seasonal variations were associated with increases in rainfall (June-September) and differences in temperature (January–May and October–January). The benzo(a)pyrene-equivalent (BaPE) and BaP results suggest that exposure to PM2.5-containing carcinogenic PAHs (C-PAHs) in Miravalle during the warm-dry and cold-dry seasons can be seen as representing a serious risk to human health. The contributions from potential sources to PAHs in PM2.5 were evaluated by the diagnostic ratios between PAHs and principal component analysis (PCA). In the whole sampling period, vehicular emission activity, probably related to light and heavy traffic, was found to be the predominant contributor to PM2.5-bound PAHs.

Particulate pollutants in the Brazilian city of São Paulo: 1-year investigation for the chemical composition and source apportionment

Abstract. São Paulo in Brazil has relatively relaxed regulations for ambient air pollution standards and often experiences high air pollution levels due to emissions of particulate pollutants from local sources and long-range transport of air masses impacted by biomass burning. In order to evaluate the sources of particulate air pollution and related health risks, a year-round sampling was done at the University of São Paulo campus (20 m a.g.l.), a green area near an important expressway. The sampling was performed for PM2. 5 ( ≤ 2. 5 µm) and PM10 ( ≤ 10 µm) in 2014 through intensive (everyday sampling in wintertime) and extensive campaigns (once a week for the whole year) with 24 h of sampling. This year was characterized by having lower average precipitation compared to meteorological data, and high-pollution episodes were observed all year round, with a significant increase in pollution level in the intensive campaign, which was performed during wintertime. Different chemical constituents, such as carbonaceous species, polycyclic aromatic hydrocarbons (PAHs) and derivatives, water-soluble ions, and biomass burning tracers were identified in order to evaluate health risks and to apportion sources. The species such as PAHs, inorganic and organic ions, and monosaccharides were determined using chromatographic techniques and carbonaceous species using thermal-optical analysis. Trace elements were determined using inductively coupled plasma mass spectrometry. The risks associated with particulate matter exposure based on PAH concentrations were also assessed, along with indexes such as the benzo[a]pyrene equivalent (BaPE) and lung cancer risk (LCR). High BaPE and LCR were observed in most of the samples, rising to critical values in the wintertime. Also, biomass burning tracers and PAHs were higher in this season, while secondarily formed ions presented low variation throughout the year. Meanwhile, vehicular tracer species were also higher in the intensive campaign, suggesting the influence of lower dispersion conditions in that period. Source apportionment was performed using positive matrix factorization (PMF), which indicated five different factors: road dust, industrial emissions, vehicular exhaust, biomass burning and secondary processes. The results highlighted the contribution of vehicular emissions and the significant input from biomass combustion in wintertime, suggesting that most of the particulate matter is due to local sources, in addition to the influence of pre-harvest sugarcane burning.

Relationship between total polar components and polycyclic aromatic hydrocarbons in fried edible oil

ABSTRACTDeep-fried dough sticks (a Chinese traditional breakfast) were fried individually in peanut, sunflower, rapeseed, rice bran, soybean and palm oil without any time lag for 32 h (64 batches fried, each for 30 min) and fried oil samples were obtained every 2 h. The frying-induced changes in the levels of total polar compounds (TPC) and polycyclic aromatic hydrocarbons (PAHs) were investigated by edible oil polar compounds (EOPC) fast separation chromatographic system and gas chromatography-mass spectrometry (GC-MS), respectively. The correlations were analysed of TPC with benzo[a]pyrene (BaP), TPC and PAH4 (benzo[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene) as well as TPC with PAH16 (USEPA 16 PAHs). The results revealed that the levels of TPC and PAHs in fried oil considerably increased with frying time, and the type of oil affected their formation, which could inform the choice of oil for frying. The total BaP equivalents (∑BaPeq) concentrations in fresh oil and in oil whose TPC exceeded 27% were 2.14–13.48 and 5.78–10.80 μg kg–1, respectively, which means that the carcinogenic potency of frying oil was more pronounced than that of fresh oil. In addition, the TPC concentration was significantly correlated with the concentrations of the sum of the 16 PAHs, PAH4 and BaP, so that the levels of PAHs could be predicted according to the levels of TPC in fried oil. In European standards, the rejection point for TPC in frying oil should be recalculated when considered PAHs. In all, the concentration of PAHs is a vital factor for ensuring the safety of frying oil.

Polycyclic aromatic hydrocarbons (PAHs) in indoor dust samples from Cities of Jeddah and Kuwait: Levels, sources and non-dietary human exposure

This study reports levels and profiles of polycyclic aromatic hydrocarbons (PAHs) in dust samples collected from three different microenvironments (cars, air conditioner (AC) filters and household floor dust) of Jeddah, Saudi Arabia (KSA) and Kuwait. To the best of our knowledge, this is first study reporting PAHs in indoor microenvironments of KSA, which makes these findings important. Benzo(b)fluoranthene (BbF), benzo(a)pyrene (BaP), phenanthrene (Phe), and pyrene (Pyr) were found to be the major chemicals in dust samples from all selected microenvironments. ΣPAHs occurred at median concentrations (ng/g) of 3450, 2200, and 2650 in Saudi AC filter, car and household floor dust, respectively. The median levels (ng/g) of ΣPAHs in Kuwaiti car (950) and household floor (1675) dust samples were lower than Saudi dust. The PAHs profile in Saudi dust was dominated by high molecular weight (HMW) (4–5 ring) PAHs while in Kuwaiti dust 3 ring PAHs have marked contribution. BaP equivalent, a marker for carcinogenic PAHs, was high in Saudi household floor and AC filter dust with median levels (ng/g) of 370 and 455, respectively. Different exposure scenarios, using 5th percentile, median, mean, and 95th percentile levels, were estimated for adults and toddlers. For Saudi and Kuwaiti toddlers worst exposure scenario of ΣPAHs was calculated at 175 and 85ng/kg body weight/day (ng/kgbw/d), respectively. For Saudi toddlers, the calculated worst exposure scenarios for carcinogenic BaP (27.7) and BbF (29.3ng/kgbw/d) was 2–4 times higher than Kuwaiti toddlers. This study is based on small number of samples which necessitate more detailed studies for better understanding of dynamics of PAHs in the indoor environments of this region. Nevertheless, our finding supports the ongoing exposure of organic pollutants to population that accumulates indoor.

Characteristics of polycyclic aromatic hydrocarbons in food oils in Beijing catering services.

The concentrations and characteristics of 16 polycyclic aromatic hydrocarbons (PAHs) in 48 oil samples randomly collected from 30 catering services that employ six cooking methods were quantified via high-performance liquid chromatography (HPLC). These 16 PAHs were detected in almost all of the samples. The levels of Σ16PAHs, Σ4PAHs, benzo[a]pyrene (BaP), and total BaP equivalents (ΣBaPeq) for the six cooking methods exceeded the legal limit. The concentrations of Σ4PAHs were approximately 9.5 to 16.4 times the legal limit proposed by the European Commission (Off J Eur Union 215:4-8, 2011), and the level of BaP exceeded the national standard in China by 4.7- to 10.6-fold, particularly in oil from fried foods. Low molecular weight PAHs (LMW PAHs) were predominant in fried food oil from different catering services and accounted for 94.8% of these oils, and the ΣBaPeq of the high molecular weight PAHs (HMW PAHs) was 11.5-fold higher than that of the LMW PAHs. The concentrations of Σ16PAHs (3751.9-7585.8μg/kg), Σ4PAHs (144.6-195.7μg/kg), BaP (79.7-135.8μg/kg), and ΣBaPeq (231.0-265.4μg/kg) were highest in the samples from fast food restaurants/buffets (FB), followed by those from fried food stalls (FS) and then cooking restaurants/cafeterias (RC). The results of this study suggest that the government should strengthen control and supervision of PAH contamination in food and edible oils.

Profile of particulate-bound organic compounds in ambient environment of Srinagar: a high-altitude urban location in the North-Western Himalayas.

Twenty-four hourly samples of total suspended particulate matter (TSPM) were collected once a week over 17months in the ambient environment of Srinagar (altitude 1524m), an urban montane location in the North-Western Himalayas. The samples were analyzed to identify and quantify the presence of diverse organic compounds (OCs) using thermal desorption gas chromatography mass spectroscopy (TD-GCMS). Non-polar organic compounds-n-alkanes, polycyclic aromatic hydrocarbons (PAHs), and molecular tracers (retene and nicotine), were detected in the TSPM samples. Molecular diagnostic ratios, derived from the quantified n-alkanes and PAHs in TSPM, assisted in characterization of the contributing sources. Significant variation in the planetary boundary layer height (meters) with change in season (summer to winter) in this region, also, affected the observed variation in the temporal profile of TSPM-bound OCs. TSPM-bound OCs were predominantly contributed from petroleum and biomass combustion; to a lesser extent from biogenic sources. High concentrations of retene and nicotine, known molecular tracers for coniferous wood combustion and tobacco smoke, respectively, were detected in the winter samples. Seasonal variation in TSPM-bound retene corresponded with the periodicity of biomass burning activity in the region. The benzo(a)pyrene equivalent (BAPE) concentrations, a measure for the carcinogenicity of TSPM-bound PAHs was calculated and the value exceeded the prescribed international standards in winter. This finding poses a major health concern for the inhabitants of this region. High BAPE concentration of PAHs during winter was linked to fossil fuel and biomass combustion, where the prevalent meteorology and topography played a synergistic role.

Source Apportionment and Risk Assessment of Polycyclic Aromatic Hydrocarbons (PAHs) in Surface Sediments from Upper Reach of Huaihe River, China

Fifteen priority PAHs in 16 sediments from upper reach of Huaihe River collected in 2007 were measured. Source apportionment derived from PCA/MLR indicated that the highest contribution to ΣPAHs was from biomass burning (34.1%), followed by coal combustion (29.7%), vehicular emission (25.8%), and coke oven origin (10.4%). Risk assessment for each identified source was quantitatively calculated by combining the benzo[a]pyrene equivalent (BaPE) with estimated source contribution. The results showed that coal combustion posed the highest toxic risk, with BaPE value of 13.1 ng g−1 dw, and the BaPE values for biomass burning, vehicular emission and coke oven were 5.6 ng g−1 dw, 7.8 ng g−1 dw, and 4.1 ng g−1 dw, respectively. The distributions of contribution for total PAHs burden and BaPE of each identified source showed similar pattern among different sampling sites.

Calculated respiratory exposure to indoor size-fractioned polycyclic aromatic hydrocarbons in an urban environment

Polycyclic aromatic hydrocarbons (PAHs) associated with inhalable particles are harmful to human health, especially to people in urban indoor environments. To evaluate human respiratory exposure to indoor PAHs properly, respiratory deposition fluxes of size-fractioned PAHs were estimated based on size-segregated distribution of PAHs in indoor air of an urban community of Guangzhou, China. The concentrations of ∑16PAH (sum of the 16 priority PAHs designated by the United States Environmental Protection Agency) were 28.9±10.0ng/m3, with the mean benzo(a)pyrene equivalent (BaPE) concentration at 4.1±1.6ng/m3. Particle size distributions of both ∑16PAH and BaPE concentrations peaked in the 1.0–1.8μm fraction. The mean respiratory deposition flux of ∑16PAH was 5.9ng/h, and accumulation mode particles contributed 20.5–83.8% of the respiratory deposition fluxes for individual PAHs. In addition, 8.6–10.2% of inhaled ∑16PAH were calculated to be deposited in the alveoli region, with accumulation particles as the largest contributor. In particular, ultrafine particles contributed 0.4–21.7% of individual PAHs deposited in the alveoli region, more than twice the fraction of the PAHs in the ultrafine particles (0.2–8.5%). Finally, lifetime cancer risk via inhalation of indoor particulate PAHs may be greater than the cancer risk guideline value (10−6), depending on specific assumptions used in this risk assessment.

PAH in airborne particulate matter.: Carcinogenic character of PM10 samples and assessment of the energy generation impact

One of the main anthropogenic sources producing Polycyclic Aromatic Hydrocarbons (PAH) is related to combustion processes especially transport, power generation processes and other industrial activities. Therefore, the main cities constitute one of the main pollution sources for population. Due to the carcinogenic character of some of these pollutants, Directive 2004/107/EC established a target value of 1.0 ng/m 3 with regard to Benzo(a)pyrene (BaP) for the total content in the particulate matter fraction averaged over a calendar year. Nevertheless, the consideration of only BaP can underestimate the carcinogenic character of the particulate matter. In this work, the carcinogenic character of the airborne PM10 of Zaragoza was studied during 2003–2004 by determining the concentration of BaP equivalents (BaP-eq), using toxic equivalent factors provided by Larsen and Larsen. Diagnostic ratios were used to discern regarding the main pollution sources in Zaragoza city in which the prevailing emission sources were related to diesel emissions and combustion sources. As PAH can travel long distances around the world, the impact of local pollution sources and long-range atmospheric transport on those samples exceeding 1.0 ng/m 3 of BaP-eq that imply higher risk for human health were assessed by considering BaA/Chry and BaP/BeP ratios and by studying the origin of the air masses with the backward air trajectories according to the HYSPLIT model. Those samples were mainly produced during cold season. The local pollution sources were the dominant sources although one episode of long-range transport from European countries could be observed.

Seasonal Variation of Polycyclic Aromatic Hydrocarbon Exposure Levels in Mexico City

This work presents the results obtained when determining the priority polycyclic aromatic hydrocarbon (PAH) concentration contained in particulate matter 10 μm in aerodynamic diameter or less (PM10) and in the gas phase in Mexico City’s atmosphere by means of a field study conducted during 2005. PM10 and vapor-phase PAHs were collected on prebaked quartz fiber filters and PUF-XAD-4 resin and quantified by gas chromatography (GC)-mass spectrometry. Vapor-phase PAHs comprised 86–97% of the total PAH mass, and naphthalene was the most abundant PAH determined, contributing 84–93% to the total mass. The benzo[a]pyrene content was on average 7% of the PAHs’ particle phase and 0.2–1% of the gas phase. The PAH concentrations measured where large industrial areas are located were 2–8 times greater during the fall/winter months (dry-cold season), when winds bear north- north-easterly, than in spring and summer. In contrast, the largest partition gas/particle ratio occurred during the dry-warm season (March–May). The results of statistical analysis using multivariate techniques suggest that motor vehicles are the main PAH contributors. The toxicity equivalence factors (TEFs) related to the carcinogenic benzo[a]pyrene potency were used for the assessment of the carcinogenic potential risk because of the measured airborne PAHs. Benzo[a]pyrene equivalent (BAPeq) concentrations were determined through multiplication of the individual PAH concentrations by their corresponding TEF value. The estimated total BAPeq for the whole field study considering only PM10 PAHs was 1085 pg m-3.However, when taking into account the PAHs in both phases, the estimated total BAPeq was 1250 pg m-3; in either case, the values were greater than the 1000-pg m-3 limit proposed by European countries.