Inhalation Of Polycyclic Aromatic Hydrocarbons Research Articles

Air-water exchange of PAHs and OPAHs at a superfund mega-site

Chemical fate is a concern at environmentally contaminated sites, but characterizing that fate can be difficult. Identifying and quantifying the movement of chemicals at the air-water interface are important steps in characterizing chemical fate. Superfund sites are often suspected sources of air pollution due to legacy sediment and water contamination. A quantitative assessment of polycyclic aromatic hydrocarbons (PAHs) and oxygenated PAH (OPAHs) diffusive flux in a river system that contains a Superfund Mega-site, and passes through residential, urban and agricultural land, has not been reported before. Here, passive sampling devices (PSDs) were used to measure 60 polycyclic aromatic hydrocarbons (PAHs) and 22 oxygenated PAH (OPAHs) in air and water. From these concentrations the magnitude and direction of contaminant flux between these two compartments was calculated. The magnitude of PAH flux was greater at sites near or within the Superfund Mega-site than outside of the Superfund Mega-site. The largest net individual PAH deposition at a single site was naphthalene at a rate of −14,200 (±5780) (ng/m2)/day. The estimated one-year total flux of phenanthrene was −7.9×105 (ng/m2)/year. Human health risk associated with inhalation of vapor phase PAHs and dermal exposure to PAHs in water were assessed by calculating benzo[a]pyrene equivalent concentrations. Excess lifetime cancer risk estimates show potential increased risk associated with exposure to PAHs at sites within and in close proximity to the Superfund Mega-site. Specifically, estimated excess lifetime cancer risk associated with dermal exposure and inhalation of PAHs was above 1 in 1 million within the Superfund Mega-site. The predominant depositional flux profile observed in this study suggests that the river water in this Superfund site is largely a sink for airborne PAHs, rather than a source.

Road Traffic Effects in Size-segregated Ambient Particle-bound PAHs

Polycyclic aromatic hydrocarbons (PAHs) in 13 size fractions of ambient particulate matter (PM) were investigated at three sites in Katowice, Poland. PM was sampled with two of the same type 13-stage low-pressure impactors (DEKATI). One of them was used first at a motorway shoulder in the spring of 2012, and then, in the summer, at a busy crossroads. The second impactor was used in parallel with the first one at an urban background site in both the seasons. The PAH contents in PM were determined by means of gas chromatography (Perkin Elmer). The ambient concentrations of PAHs from particular PM fractions at the urban background site differed insignificantly from those at the two traffic sites. Although the concentrations of PAHs and total PAHs (ΣPAH) for some PM size fractions were higher at the urban background site, the significant influence of traffic emissions on the mass size distributions and concentrations of PAHs in Katowice was proved. For example, the traffic effects can be seen in the shares of the PM1-bound ΣPAH and some PM1-bound PAHs in the concentrations of PM-bound ΣPAH and these PAHs, visibly higher at the motorway and crossroads. Also, the mass size distributions of some PM-bound PAHs reflect the traffic influence on the ambient PAH concentrations within the whole city in summer. As the traffic emissions cause high concentrations of PM-bound BaP and BaA, these two PAHs probably pose the main health risk related with ambient PAH inhalation in non-heating periods in Katowice.

Lung cancer risk by polycyclic aromatic hydrocarbons in a Mediterranean industrialized area

This study focuses on characterizing the chronic risk assessment from inhalation of polycyclic aromatic hydrocarbons (PAHs) for people living near the largest chemical complex in the Mediterranean area. Eighteen PAHs were determined in the atmospheric gas and particle phases, counting PM10 and total suspended particles. The lifetime lung cancer risk from PAH exposure was estimated, and the contribution was assessed by phases. The results obtained with the continuous lifetime scenario were compared with those obtained with different chronic scenarios. The estimated chronic risk was also compared with those reported in previous studies. PAHs were present at higher concentration in the gas phase (>84%) with a major contribution of the most volatile PAHs, and an equitable distribution of heavy PAHs between gas and particle phases was observed. Petroleum combustion and traffic emissions were suggested as the main sources, but the influence of petrogenic sources cannot be ruled out. The estimated average lifetime lung cancer risk in this study ranged between 3.2×10-5 and 4.3×10-5. The gas phase accounted for the most significant contribution to the total risk (>60%). Fluoranthene (FluT), dibenzo(a,h)anthracene (DahA) and benzo(a)pyrene (BaP), as a whole, made the greatest contribution to the total risk (>80%). BaP-bound PM10 accounted for a small contribution of the total risk (10%). Chronic exposures lower than total lifetime hours could even pose a risk >10-5. The results also showed that BaP-bound PM10, according to current legislation, may not be a good indicator of the real risk by PAH exposure. Concerning previous studies, the economic situation may have an impact on reducing the cancer risk by PAH inhalation.

Determination of PM2.5 and polycyclic aromatic hydrocarbons from incense burning emission at shrine for health risk assessment

This study aims to determine fine particles (PM2.5) and polycyclic aromatic hydrocarbons (PAHs) bounded with PM2.5 emitted from incense burning at shrine to assess human health risk. The PM2.5 samples were collected by a mini volume air sampler during special occasions and normal period at a shrine located in the city center of Chiang Mai, Thailand. The samples were analyzed for 16-PAHs by GC–MS. The descending order of 8- and 24-hrs PM2.5 concentrations (μg/m3) were 625 ± 147 and 406 ± 159 (Chinese New Year) > 184 ± 85 and 133 ± 71 (other special occasions) > 100 ± 35 and 50 ± 20 (normal period). Their concentrations in each occasion were significantly different due to number of visitors and amount of incense being burned. Total PAHs concentrations (ng/m3) for 8- and 24-hrs in descending order were 90 ± 41 and 45 ± 29 (Chinese New Year), 71 ± 30 and 30 ± 12 (other special occasions) and 25 ± 15 and 14 ± 9 (normal periods). Correlation between PM2.5 and total PAHs concentrations was relatively strong. In addition, PM2.5 concentrations were highly correlated (r = 0.618) with carcinogenic PAHs (c-PAHs) indicated that carcinogenic compounds were dominant in particulate PAHs and generated from incense burning. The values of toxicity equivalent concentration (TEQ) indicate human health risk from PAHs inhalation. According to European guideline, it should be less than1 ng/m3 in ambient air. During Chinese New Year, they were relatively high (32 ± 27 ng/m3 (8 h) and 10 ± 4 ng/m3 (24 h)). Moreover, the isometric ratio analysis revealed that emission from incense burning was the main source of PM2.5 and PM2.5-bound PAHs.

Assessment of polycyclic aromatic hydrocarbons in indoor dust from varying categories of rooms in Changchun city, northeast China

Sixteen polycyclic aromatic hydrocarbons (PAHs) were isolated from indoor dust from various categories of rooms in Changchun city, northeast China, including dormitory, office, kitchen, and living rooms. PAH concentrations ranged from 33.9 to 196.4μgg-1 and 21.8 to 329.6μgg-1 during summer and winter, respectively, indicating that total PAH concentrations in indoor dust are much higher than those in other media from the urban environment, including soils and sediments. The percentage of five- to six-ring PAHs was high, indicating that PAHs found in indoor dust mainly originate from pyrolysis rather than a petrogenic source. Rooms were divided into three groups using cluster analysis on the basis of 16PAH compositions, namely smoke-free homes, homes exposed to smoke and offices. Results showed that the source of PAHs in smoke-free residential homes is primarily the burning of fossil fuels. In addition to the burning of fossil fuels, biomass combustion and cooking contributed to PAHs in houses exposed to smoke (including kitchens). Motor vehicles are an additional source of PAHs in offices because of greater interactions with the outdoor environment. The results of health risk assessment showed that the cancer risk levels by dermal contact and ingestion are 104- to 105-fold higher than that by inhalation, suggesting that ingestion and dermal contact of carcinogenic PAHs in dust are more important exposure routes than inhalation of PAHs from air. Although the results showed high potential of PAH concentrations in indoor dust in Changchun for human health risk, caution should be taken to evaluate the risk of PAHs calculated by USEPA standard models with default parameters because habitation styles are different in various categories of rooms.

Level, potential sources of polycyclic aromatic hydrocarbons (PAHs) in particulate matter (PM10) in Naples

Abstract In Naples, particulate matter PM10 associated with polycyclic aromatic hydrocarbons (PAHs) in ambient air were determined in urban background (NA01) and urban traffic (NA02) sites. The principal objective of the study was to determine the concentration and distribution of PAHs in PM10 for identification of their possible sources (through diagnostic ratio - DR and principal component analysis - PCA) and an estimation of the human health risk (from exposure to airborne TEQ). Airborne PM10 samples were collected on quartz filters using a Low Volume Sampler (LVS) for 24 h with seasonal samples (autumn, winter, spring and summer) of about 15 days each between October 2012 and July 2013. The PM10 mass was gravimetrically determined. The PM10 levels, in all seasons, were significantly higher (P The concentration of Benzo[a]Pyrene, BaP (EU and National limit value: 1 ng m−3 in PM10), varied from 0.065 ng m−3 during autumn time to 0.872 ng m−3 in spring time (NA01) and from 0.120 ng m−3 during autumn time to 1.48 ng m−3 of winter time (NA02) with four overshoots. In NA02 the trend of Σ12 PAHs was comparable to NA01 but were observed higher values than NA01. In fact, the mean concentration of Σ12 PAHs, in urban-traffic site was generally 2 times greater than in urban-background site in all the campaigns. PAHs with 5 and 6 ring, many of which are suspected carcinogens or genotoxic agents, (i.e Benzo[a]Pyrene, Indeno[1,2,3-cd]Pyrene, Benzo[b]Fluoranthene, Benzo[k]Fluoranthene and Benzo[g,h,i]Perylene), had a large contribution (∼50–55%) of total PAHs concentration in PM10 in two sites and in each of the campaigns. Diagnostic ratio analysis and PCA suggested a substantial contributions from traffic emission with minimal influence from coal combustion and natural gas emissions. In particular diesel vehicular emissions were the major source of PAHs at the studied sites. The use of Toxicity Equivalence Quantity (TEQ) concentration provide a better estimation of carcinogenicity activities; health risk to adults and children associated with PAHs inhalation was assessed by taking into account the lifetime average daily dose and corresponding incremental lifetime cancer risk (ILCR). The ILCR was within the acceptable range (10−6–10−4), indicating a low health risk to residents in these areas.

High Concentrations of Organic Contaminants in Air from Ship Breaking Activities in Chittagong, Bangladesh.

The beaches on the coast of Chittagong in Bangladesh are one of the most intense ship breaking areas in the world. The aim of the study was to measure the concentrations of organic contaminants in the air in the city of Chittagong, including the surrounding ship breaking areas using passive air samplers (N = 25). The compounds detected in the highest amounts were the polycyclic aromatic hydrocarbons (PAHs) and short-chain chlorinated paraffins (SCCPs), whereas dichlorodiphenyltrichloroethanes (DDTs), hexachlorobenzene (HCB), and polychlorinated biphenyls (PCBs) were several orders of magnitude lower in comparison. PCBs, PAHs, and HCB were highest at sites near the ship breaking activities, whereas DDTs and SCCPs were higher in the urban areas. Ship breaking activities likely act as atmospheric emission sources of PCBs, PAHs, and HCB, thus adding to the international emphasis on responsible recycling of ships. Concentrations of PAHs, PCBs, DDTs, HCB, and SCCPs in ambient air in Chittagong are high in comparison to those found in similar studies performed in other parts of Asia. Estimated toxic equivalent quotients indicate elevated human health risks caused by inhalation of PAHs at most sites.

Household air pollution and personal exposure risk of polycyclic aromatic hydrocarbons among rural residents in Shanxi, China.

Polycyclic aromatic hydrocarbons (PAHs) are a group of pollutants of widespread concerns. Gaseous and size-segregated particulate-phase PAHs were collected in indoor and outdoor air in rural households. Personal exposure was measured and compared to the ingestion exposure. The average concentrations of 28 parent PAHs and benzo(a)pyrene (BaP) were 9000±8390 and 131±236ng/m(3) for kitchen, 2590±2270 and 43±95ng/m(3) for living room, and 2800±3890 and 1.6±0.7ng/m(3) for outdoor air, respectively. The mass percent of high molecular weight (HMW) compounds with 5-6 rings contributed 1.3% to total 28 parent PAHs. Relatively higher fractions of HMW PAHs were found in indoor air compared to outdoor air. Majorities of particle-bound PAHs were found in the finest PM0.25 , and the highest levels of fine PM0.25 -bound PAHs were in the kitchen using peat and wood as energy sources. The 24-h personal PAH exposure concentration was 2100±1300ng/m(3) . Considering energies, exposures to those using wood were the highest. The PAH inhalation exposure comprised up to about 30% in total PAH exposure through food ingestion and inhalation, and the population attributable fraction (PAF) for lung cancer in the region was 0.85%. The risks for inhaled and ingested intakes of PAHs were 1.0×10(-5) and 1.1×10(-5) , respectively.

Levels, potential sources and human health risk of polycyclic aromatic hydrocarbons (PAHs) in particulate matter (PM(10)) in Kumasi, Ghana.

Airborne particulate samples were collected on quartz filters to determine the concentrations, sources and health risks of polycyclic aromatic hydrocarbons (PAHs) in air in Kumasi, Ghana. A total of 32 air samples were collected in Kwame Nkrumah University of Science and Technology (KNUST) campus (pristine site) and city centre (CC). Samples were extracted with 1:2 v/v acetone/hexane mixture prior to GC-MS analyses. The sum of concentrations of 17 PAHs in air ranged from 0.51 to 16 (KNUST) and 19-38 ng/m(3) (CC). The concentration of benzo[a]pyrene, BaP, ranged from below detection limit to 0.08 ng/m(3) (KNUST) and 1.6 to 5.6 ng/m(3) (CC). Chemical mass balance model showed that PAHs in air in Kumasi were mainly from fuel combustion. The total BaP equivalent concentration (BaPeq) in CC was 18 times higher compared to KNUST; based on the European Legislation and Swedish and UK Standards for BaP in air, CC could be classified as highly polluted. Estimated carcinogenicity of PAHs in terms of BaPeq indicated that BaP was the principal PAH contributor in CC (70%). Health risk to adults and children associated with PAH inhalation was assessed by taking into account the lifetime average daily dose and corresponding incremental lifetime cancer risk (ILCR). The ILCR was within the acceptable range (10(-6) to 10(-4)), indicating low health risk to residents.

Airborne polycyclic aromatic hydrocarbons in a medium-sized city affected by preharvest sugarcane burning and inhalation risk for human health

Polycyclic aromatic hydrocarbons (PAHs) in air were measured in a municipality where sugarcane plantations are extensive, at three sites, one in the city center and two in rural localities. Twenty-four-hour sampling was done using PS1 PUF samplers from Andersen Instruments Inc., at least 1 day per month per site, from June 2009 to October 2009. The chemical analyses were performed by gas chromatography–mass spectrometry (GC/MS) for the 16 most toxic PAHs. The incremental lifetime cancer risk (ILTR) by inhalation was determined by the Monte Carlo method for the urban population using Crystal Ball software. The total concentration of the 16 PAHs at all sites varied from 6.2 to 65.7 ng m−3, with an average of 25.9 ± 18.2 ng m−3. The average concentrations per site were 14.1 ± 13.0 ng m−3 at rural site B, 20.7 ± 11.5 ng m−3 at rural site A, and 36.1 ± 22.7 ng m−3 at the central site. The cancer risk for infants, children, and adults was approximately 14%, 25%, and 61% of the total IRLT, respectively. The mean (95% upper probability limit [95% UPL]) values were 1.2 × 10−7 (2.2 × 10−7) for infants, 2.2 × 10−7 (4.1 × 10−7) for children, and 8.9 × 10−7 (1.1 × 10−6) for adults. Although the three most abundant PAHs found were phenanthrene, fluoranthene, and pyrene, the three most important contributions to the incremental risk of cancer came from benzo[a]pyrene, benzo[b]fluoranthene, and naphthalene. Compared with the risks in big cities such as São Paulo, this would be low, but not negligible. Analysis of ratios of PAHs according to the literature showed that vehicle exhaust and biomass burning, including sugarcane burning, seem to be the most important contributors to PAH concentrations in the central area of Araraquara City.Implications:The growth of biofuel use worldwide, especially ethanol, together with preharvesting burning practice, is cause of concern with regard to possible health effects, due to increased air pollution levels in cities in regions where sugarcane plantation and processing are intensive. This paper shows that the risk of cancer from PAH inhalation in an urban area surrounded by sugarcane agriculture was of the same order of magnitude as the tolerable risk value of 10−6. As other classical and hazardous pollutants are also present, care should be taken to keep pollution as low as possible to protect human health.

Personal inhalation exposure to polycyclic aromatic hydrocarbons in urban and rural residents in a typical northern city in China

Personal inhalation exposure samples were collected and analyzed for polycyclic aromatic hydrocarbons (PAHs) for 126 selected volunteers during heating and non-heating seasons in a typical northern Chinese city, Taiyuan. Measured personal PAH exposure levels for the urban residents in the heating and non-heating seasons were 690 (540-1051) and 404 (266-544) ng/m(3) , respectively, while, for the rural residents, they were 770 (504-1071) and 312 (201-412) ng/m(3) , respectively. Thus, rural residents are exposed to lower PAH contamination in comparison with the urban residents in the non-heating seasons. In the heating season, personal PAH inhalation exposure levels were comparable between the urban and rural residents, in part owing to the large rate of residential solid fuel consumption in the rural area for household cooking and heating. The estimated incremental lifetime cancer risks (ILCR) due to PAH exposure in Taiyuan were 3.36×10(-5) and 2.39×10(-5) for the rural and urban residents, respectively, significantly higher than the literature-reported national average level, suggesting an urgent need of PAH pollution control to protect human health.

Analysis of Intervention Strategies for Inhalation Exposure to Polycyclic Aromatic Hydrocarbons and Associated Lung Cancer Risk Based on a Monte Carlo Population Exposure Assessment Model

It is difficult to evaluate and compare interventions for reducing exposure to air pollutants, including polycyclic aromatic hydrocarbons (PAHs), a widely found air pollutant in both indoor and outdoor air. This study presents the first application of the Monte Carlo population exposure assessment model to quantify the effects of different intervention strategies on inhalation exposure to PAHs and the associated lung cancer risk. The method was applied to the population in Beijing, China, in the year 2006. Several intervention strategies were designed and studied, including atmospheric cleaning, smoking prohibition indoors, use of clean fuel for cooking, enhancing ventilation while cooking and use of indoor cleaners. Their performances were quantified by population attributable fraction (PAF) and potential impact fraction (PIF) of lung cancer risk, and the changes in indoor PAH concentrations and annual inhalation doses were also calculated and compared. The results showed that atmospheric cleaning and use of indoor cleaners were the two most effective interventions. The sensitivity analysis showed that several input parameters had major influence on the modeled PAH inhalation exposure and the rankings of different interventions. The ranking was reasonably robust for the remaining majority of parameters. The method itself can be extended to other pollutants and in different places. It enables the quantitative comparison of different intervention strategies and would benefit intervention design and relevant policy making.

A comparative assessment of PM2.5exposures in light-rail, subway, freeway, and surface street environments in Los Angeles and estimated lung cancer risk

According to the U.S. Census Bureau, 570000+ commuters in Los Angeles travel for over 60 minutes to work. Studies have shown that a substantial portion of particulate matter (PM) exposure can occur during this commute. This study represents the integration of the results from five commute environments in Los Angeles. Personal PM exposures are discussed for the: (1) METRO gold line, a ground-level light-rail route, (2) METRO red line, a subway line, (3) the 110, a high volume freeway with low heavy-duty vehicle (HDV) fraction, (4) the 710, a major corridor for HDVs from the Port of Los Angeles, and (5) Wilshire/Sunset Boulevards, major surface streets. Chemical analysis including total and water-soluble metals and trace elements, elemental and organic carbon (EC/OC), and polycyclic aromatic hydrocarbons (PAHs) was performed. The focus of this study is to compare the composition and estimated lung cancer risk of PM2.5 (dp < 2.5 μm) for the five differential commute environments. Metals associated with stainless steel, notably Fe, Cr, and Mn, were elevated for the red line (subway), most likely from abrasion processes between the rail and brakes; elements associated with tire and brake wear and oil additives (Ca, Ti, Sn, Sb, and Pb) were elevated on roadways. Elemental concentrations on the gold line (light-rail) were the lowest. For water-solubility, metals observed on the red line (subway) were the least soluble. PAHs are primarily derived from vehicular emissions. Overall, the 710 exhibited high levels of PAHs (3.0 ng m−3), most likely due to its high volume of HDVs, while the red and gold lines exhibited low PAH concentrations (0.6 and 0.8 ng m−3 for red and gold lines, respectively). Lastly, lung cancer risk due to inhalation of PAHs was calculated based on a commuter lifetime (45 years for 2 hours per workday). Results showed that lung cancer risk for the 710 is 3.8 and 4.5 times higher than the light-rail (gold line) and subway (red line), respectively. With low levels of both metal and PAH pollutants, our results indicate that commuting on the light-rail (gold line) may have potential health benefits when compared to driving on freeways and busy roadways.

Olympic Win: Lower Estimated Cancer Risk with Air Pollution Controls during the 2008 Beijing Games

Polycyclic aromatic hydrocarbons (PAHs) sorbed to fine atmospheric particulate matter (PM2.5) increase inhalation cancer risk in exposed populations. In China each year, an estimated 6.5 people per million develop lung cancer due to PAH inhalation. But stringent air pollution control measures instituted during the 2008 Olympic Games in Beijing, if sustained over a lifetime, could reduce residents’ PAH-related inhalation cancer risk by nearly half [EHP 119(6):815–820; Jia et al.]. Coal combustion and motor vehicle emissions create severe air pollution in Beijing and other major Chinese cities. To improve air quality for the Olympic Games, factories in and around Beijing were moved or closed, vehicular traffic was restricted, and truck traffic was reduced during the period 20 July–20 September 2008. During the games themselves (8–24 August), even stricter controls were imposed. PM2.5 samples were collected at a single representative location in Beijing, and associated concentrations of 17 PAHs were measured and compared for four periods: 1) 28 July–20 September versus 2) 21 September–7 October, and 3) 8–24 August versus 4) 28 July–7 August/25 August–7 October. To enable direct comparison of chemical risks, a benzo[a]pyrene equivalent (BaPeq) concentration was estimated for each PAH by multiplying its concentration by its relative potency factor (RPF). Cancer risk was calculated using the BaPeq values paired with previously established unit risk measures for cancer based on a lifetime (70 years) of BaP exposure at 1 μg/m3 air. Individual BaPeq concentrations were 22–78% lower in period 1 compared with period 2 (i.e., when any pollution controls were in place) and 32–72% lower in period 3 compared with period 4 (i.e., when the strictest controls were in place). Lifetime excess inhalation cancer cases estimated during the period when pollution was controlled ranged from 6.5 to 518 individuals per million compared with a range of 12.2–964 per million after pollution controls ceased—a 46% reduction. PAHs from the U.S. Environmental Protection Agency’s list of priority pollutants made up three of the four largest contributors to total carcinogenicity; however, high-molecular-weight PAHs—a highly carcinogenic group of chemicals that, as a class, haven’t been extensively studied—contributed a considerable 23% of the cancer risk. These top four PAHs are primarily associated with PM2.5, so reducing PM2.5 emissions would also reduce levels of these and other PAHs. Limitations of the study include potential inaccuracies due to its point-estimate approach, which assumes additive cancer risk, and the RPF values, which were based on toxicologic studies with their own uncertainties. However, the study strongly supports the effectiveness of air pollution source control measures and also demonstrated the need to include high-molecular-weight PAHs in future studies.

Polycyclic Aromatic Hydrocarbons (PAHs) in Soil and Sediment from Industrial, Residential, and Agricultural Areas in Central South Africa: An Initial Assessment

Polycyclic aromatic hydrocarbons (PAHs) are of global concern due to their ubiquitous presence, toxicity, and carcinogenicity. No data on PAHs in soils from South Africa have been published, even though it has the largest economy and industrial base in Africa. During this initial assessment, the levels of PAHs were determined in soils and sediments collected from central South Africa, specifically targeting industrial, residential, and agricultural areas. Analysis was performed by gas chromatography/mass spectrometry (GC/MS). The total concentration of PAHs (Σt-PAH) ranged between 44 and 39,000 ng/g, dw and the concentration of carcinogenic PAHs (Σc-PAH) ranged between 19 and 19,000 ng/g, dw. Pyrogenic processes were the most likely sources, with minimal petrogenic contributions. PAH levels were in the same range as levels reported from other countries, and the majority of the sites did not exceed Canadian environmental quality guidelines. Based on assumptions for dermal contact and ingestion of PAH-contaminated soil, we provisionally calculated only a small increase in cancer risk, but additional PAH inhalation could add considerably to this risk. Our data indicates a need for more analysis in industrial and residential areas, and should include air.

Assessment of carcinogenic risk due to inhalation of polycyclic aromatic hydrocarbons in PM 10 from an industrial city: A Korean case-study

This study investigated the effects of meteorological conditions and spatial variations on the toxicity of polycyclic aromatic hydrocarbons (PAHs) in airborne PM 10 in Ulsan, the largest industrial city in Korea. Daily PM 10 samples were collected on quartz microfiber filters using high volume samplers located in a downtown area, a residential area and an industrial area of Ulsan during spring and summer sampling periods. Sixteen individual PAHs were extracted into a mixture solution of dichloromethane and n-hexane (1:1, v/v) in an ultrasonic bath and were analyzed using a high performance liquid chromatography system with an ultra-violet detector (HPLC-UVD). The average total PAH concentrations from the three representative sampling sites of Ulsan ranged from 16.15 to 57.12 ng/m 3 in spring and from 11.11 to 34.56 ng/m 3 in summer. The toxicity equivalent concentrations (TEQs) of the PAHs in PM 10 of Ulsan ranged from 1.82 to 13.1 ng/m 3, with an average level of 4.17 ng/m 3. The highest TEQs were found in the downtown area, which had an average value of 6.30 ng/m 3 in spring and 5.52 ng/m 3 in summer. BaP and DahA were identified as the major carcinogenic PAHs that contributed to 34.8 and 59.4% of the total carcinogenic potency of PAHs in PM 10 in Ulsan. The identified TEQs were highly correlated ( r 2 = 0.73–0.90, p < 0.01) with the total PAH concentrations for each area. The TEQs showed a significant correlation ( p < 0.01) with the concentration of air pollutants, including PM 10, PM 2.5 and NO 2.

The carcinogenic risk and variability of particulate-bound polycyclic aromatic hydrocarbons with consideration of meteorological conditions

Epidemiological and laboratory studies suggest that atmospheric particulate matter and polycyclic aromatic hydrocarbons (PAHs) have a strong association with cancer prevalence and risk. Health hazards from PAH inhalation emanate mainly if these compounds are bound to particulate matter, whereas the depth of penetration and retention in the human organism is greatly dependent on the size and morphology of the particle. We determined the distribution of 21 PAHs over different particle size fractions and investigated the influence of meteorological conditions on the partitioning between air and particle phase and the distribution over different size fractions. The highest PAH concentration was found in a size range from 0.35 to 1.2 μm. About two-thirds of the total PAH concentration were associated to respirable particles smaller than 1.2 μm, highlighting the importance of considering fine particles in cancer risk assessment. High temperature and sunshine duration were associated with decreased PAH contamination, while humidity was associated with increased PAH contamination. We found that high molecular weight compounds had an increased tendency to be sorbed to smaller particles. Approximately 30% of the overall carcinogenicity of the samples, determined by a dose addition model, was contributed by benzo[a]pyrene. However, the relative contribution of benzo[a]pyrene to the overall carcinogenicity varied greatly over different samples and size fractions, suggesting that benzo[a]pyrene alone is not an adequate indicator compound for assessment of carcinogenicity. Instead, we suggest integrating nine PAHs, which together contributed approximately 93% to the overall carcinogenicity, into a sum parameter serving as an indicator for carcinogenic potential.

Pollution level, phase distribution and source analysis of polycyclic aromatic hydrocarbons in residential air in Hangzhou, China

A survey of polycyclic aromatic hydrocarbons (PAHs) in residential air in Hangzhou, China, was carried out. Air samples were collected from indoor and outdoor environments during both summer and winter and analyzed for the level of 16 PAHs. The results showed total PAH contents ranging from 0.425 to 36.2 μg/m 3 with highest concentrations in the kitchen areas generally. Particulate PAHs were predominantly absorbed on PM 2.5 with proportion of 59–97% to total particulate phase, followed by PM 2.5–10 (3–24%) and PM >10 (0–17%). PAH concentrations in indoor air of smoking residences tended to be higher than those of nonsmoking residences. Outdoor environment, Chinese conventional cooking practice, mothball emission and unknown source accounted for −10.5%, 32.8%, 71.5% and 6.2% of total PAHs in indoor air of nonsmoking residences, respectively. Outdoor environment was the fate for indoor PAHs in general, and consumed 10.5% of total PAHs. Finally, health risks associated with the inhalation of PAHs were assessed, and the results indicated that health-based guideline levels for lung cancer risk were exceeded. The largest contribution to total health risks in summer and winter was NA (72.9%) and BaP (45.2%), respectively.

Mixed uncertainty analysis of polycyclic aromatic hydrocarbon inhalation and risk assessment in ambient air of Beijing

This article presents the application of an integrated method that estimates the dispersion of polycyclic aromatic hydrocarbons (PAHs) in air, and assesses the human health risk associated with PAHs inhalation. An uncertainty analysis method consisting of three components were applied in this study, where the three components include a bootstrapping method for analyzing the whole process associated uncertainty, an inhalation rate (IR) representation for evaluating the total PAH inhalation risk for human health, and a normally distributed absorption fraction (AF) ranging from 0% to 100% to represent the absorption capability of PAHs in human body. Using this method, an integrated process was employed to assess the health risk of the residents in Beijing, China, from inhaling PAHs in the air. The results indicate that the ambient air PAHs in Beijing is an important contributor to human health impairment, although over 68% of residents seem to be safe from daily PAH carcinogenic inhalation. In general, the accumulated daily inhalation amount is relatively higher for male and children at 10 years old of age than for female and children at 6 years old. In 1997, about 1.73% cancer sufferers in Beijing were more or less related to ambient air PAHs inhalation. At 95% confidence interval, approximately 272-309 individual cancer incidences can be attributed to PAHs pollution in the air. The probability of greater than 500 cancer occurrence is 15.3%. While the inhalation of ambient air PAHs was shown to be an important factor responsible for higher cancer occurrence in Beijing, while the contribution might not be the most significant one.

Simulation and health risk assessment of residential particle pollution by coal combustion in China

In China, residential coal combustion has resulted in serious indoor air pollution, and the emitted particulate matters and associated toxic organic compounds are greatly harmful to human health. For example, the high lung cancer mortality in Xuanwei County, Yunnan Province was attributed to inhalation of polycyclic aromatic hydrocarbons (PAHs)-coated particles within the houses. Based on previous investigations, this paper simulated the indoor particle pollution from coal combustion for a typical home in Xuanwei by computational fluid dynamics (CFD) method. Benzo[ a]pyrene (BaP), one of the important pollutants from incomplete combustion, was used as a criterion for its strong carcinogenicity in risk assessment. Mechanical exhaust fan was installed in order to reduce the concentration of suspended particles indoors. Based on the simulated results, an engineering-oriented method was demonstrated to be effective in assessing indoor particle pollution by coal combustion and its health effect. Results indicated that the indoor particle pollution was rather serious due to the poor ventilation. Women, who spent more time indoors than men, had higher risk for lung cancer, and the predicted incidence for local people accorded well with previous surveys [Chapman RS, Mumford JL, Harris DB. The epidemiology of lung cancer in Xuanwei, China: current process, issues and research strategies. Archives of Environmental Health 1988;43(2):180–5]. The installation of the exhaust fan turned out to be effective in removing indoor particles since it greatly strengthened airflows and the contaminant removal is significantly improved.