Inhalation Of Polycyclic Aromatic Hydrocarbons Research Articles

Variations of source-specific risks for inhalable particles-bound PAHs during long-term air pollution controls in a Chinese megacity: Impact of gas/particle partitioning

Gas/particle (G/P) partitioning is a determining factor that drives the behavior of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere. To comprehend the variations and impacts of PAHs G/P partitioning on inhalation risks from different sources, atmospheric PAHs in Chengdu were studied from January 2009 to January 2021. Chengdu's air quality demonstrated improvement, with a noticeable decline in PM10 (from 238 to 103 μg m−3), PM10-bound PAHs mass concentrations (from 0.08 to 0.01 μg m−3), as well as PAHs inhalation non-cancer (from 63.5 to 7.1) and cancer risks (from 6.2 × 10−5 to 7.7 × 10−6). Decreasing trends were also observed in the concentrations of organic carbon (OC) and the values of absorptive G/P partitioning coefficient (Kp, OM) from 2009 to 2020, indicating a slight decrease in the PM absorptive capacity. A positive matrix factorization (PMF) model utilized three distinct datasets: PMFpp (particle-phase PAHs only), PMFtot (total PAHs concentrations), and PMFpp/gas (particle-phase in parallel with gas-phase PAHs). PMFpp and PMFpp/gas provide reasonable source apportionment and source-specific risk results. However, daily variations in source contributions of PMFtot were found to be unreasonable. PMFpp/gas and PMFtot could identify a source of low molecular weight PAHs (LPAHs) related to temperature, and a significantly positive correlation between LPAHs and temperature was discovered. Gas/particle partitioning of PAHs showed a notable impact on source-specific risks associated with coal and biomass combustion (CC&BC). The findings contribute to our understanding of the variation in PAHs G/P partitioning and the PM absorptive capacity resulting from effective air pollution control in China. Additionally, they offer prerequisite information for incorporating semi-volatile organic compounds in source apportionment and source-specific risk assessment.

Effect of Polycyclic Aromatic Hydrocarbons (PAHs) on Respiratory Diseases and the Risk Factors Related to Cancer

Polycyclic aromatic hydrocarbons (PAHs) are a large group of organic compounds that have 2–7 benzene rings. PAHs causes many complications in humans, including respirations and increased risk of cancer. The most important fixed and mobile sources (PAHs) include food, industrial pollution, and car exhaust. The most common ways of entering the body (PAHs) are through direct contact, seafood, grilled meat, inhalation of PAHs, and contaminated water. From various studies and many publications in the field, the major issue with PAHs is increased risk of cancer, such as cancer of lungs if inhaled or skin if in contact with skin, cancer of stomach or gastrointestinal in smoked or barbecued fish and meat products. The purpose of this review study was to the epidemiological literature on the side effect of Polycyclic aromatic hydrocarbons (PAHs) on respiratory diseases and the risk factors related to Cancer. Six hundred and fifty-five articles according to different databases: Google Scholar, PubMed, Web of Science, BMJ, Springer, and Science Direct were retrieved. Forty-two studies were screened after review and, 27 full-text articles were entered into the analysis process. Finally, 15 articles were selected for this study. Studies have shown the effects of PAHs in increasing the risk of infection in the respiratory system, including asthma, lung dysfunction, and various cancers, such as skin, digestive tract, lung, and blood. The results showed that polycyclic aromatic hydrocarbons could increase the probability and risk incidence of cancers of the lung, skin, bladder, and respiratory diseases, such as asthma and lung dysfunction. Reducing the emission of polycyclic aromatic hydrocarbons (PAHs) due to activities, such as cooking, car exhaust, wildfire, and power plant can be a very influential factor in reducing the health endpoint of this pollutant, especially respiratory diseases, and Cancer.

Environmental and human health risk assessments of polycyclic aromatic hydrocarbons in particulate matter in Nigeria.

Polycyclic aromatic hydrocarbons (PAHs) are an important organic group in particulate matter which has attracted much attention among the scientific community in terms of health risk because of their carcinogenic, mutagenic, and ubiquitous nature in the environment. In this study, PAHs in particulate matter in Okitipupa were determined. Indoor and outdoor particle samples were sampled with the aid of SKC Air Check XR5000 high-volume gravimetric sampler, and analyzed using gas chromatography flame ionization detector (GC-FID). The results obtained showed that high molecular weight PAHs (5-ring, 6-ring PAHs) had higher mean concentration than low molecular weight PAHs (2-ring, 3-ring PAHs), in both indoor and outdoor particulate matter. Health risk assessments from exposure to these PAHs were also determined using toxicity equivalence quotient (TEQ), mutagenicity equivalence quotient (MEQ), incremental life cancer risk (ILCR), and hazard quotient (HQ). Dibenz(a,h)anthracene had the highest mean concentration across the sample location in both indoor and outdoor with values ranging from 33 to 31 and 90 to 93µg/m3 respectively. The total mean concentration in outdoor PAHs ranged from 280 to 329µg/m3, while total mean concentration in indoor PAHs ranged from 74 to 104µg/m3. The incremental lifetime cancer risk in indoor ranged from 6.9 × 10-7 to 1.2 × 10-5, while the ILCR in outdoor ranged from 8.5 × 10-6 to 1.0 × 10-5. The hazard quotient in indoor ranged from 7.6 × 10-5 to 2.2 × 10-3, while the HQ in outdoor ranged from 10 × 10-4 to 1.4 × 10-3. These values are within the WHO permissible limit, and therefore underscores the danger associated with the inhalation of polycyclic aromatic hydrocarbons in Okitipupa.

Assessment of the temporal variability and health risk of atmospheric particle-phase polycyclic aromatic hydrocarbons in a northeastern city in China.

In this study, we examined the sources and temporal variability of 16 polycyclic aromatic hydrocarbons (PAHs) found in fine particulate matter (PM2.5) in a typical industrial city in northern China. We also evaluated the incremental lifetime cancer risk (ILCR) from the inhalation of these PAHs. Atmospheric PM2.5 samples were collected for 7 consecutive days each month from 2014 to 2019, and the 16 PAHs were measured using multiplex gas chromatography-tandem mass spectrometry. The carcinogenic risk of PAH exposure was assessed using the inhalation unit risk (IUR) and cancer slope factor (CSF) methods. The annual average concentrations of PM2.5 for each year from 2014 to 2019 were 102.87±55.25, 86.92±60.43, 69.17±37.74, 58.20±59.15, 56.01±34.52, and 52.54±58.15 µg m-3, and the annual average ΣPAH concentrations were 56.03±81.09, 47.99±79.30, 40.41±57.31, 33.57±51.79, 43.23±74.80, and 25.20±50.91 ng m-3, respectively. Source identification, using diagnostic ratio analysis, indicated that the major PAH sources were coal/biomass combustion, fuel combustion, and traffic emissions. A health risk assessment showed that the ILCR from PAH inhalation decreased throughout the study period and varied with age. The IUR and CSF methods both showed that the adult ILCR exceeded 1.0×10-6. These findings demonstrate the importance of addressing the carcinogenic risk of PM2.5-bound PAHs, particularly in adults.

Assessment of polycyclic aromatic hydrocarbons in indoor air of local public eatery in Ado-Ekiti, Western Nigeria

Polycyclic aromatic hydrocarbons (PAHs) are pollutants generated during the incomplete combustion of fossil fuels and organic materials. In Nigeria, most local eateries, canteens, and commercial cooking operate using charcoal or wood as fuel for energy towards food preparation and their kitchens are usually close to the sitting area of the customers. Hence, this study determined the concentrations of PAHs in some selected local public eatery in Western Nigeria; it also determined the possible implication of exposure to PAHs emanating from these kitchens to customer health. 16 PAHs were monitored in some selected eateries and canteens in Ado Ekiti, Nigeria using Polyurethane Foam (PUF) passive samplers. Analysis of PAHs was done using HP 6890/5973 GC-MS on selected ionization mode (SIM). The findings revealed the mean PAHs concentration range of 0.163 - 0.239 ngm−3. The values of incremental lifetime cancer risk (ILCR) and Hazard Quotient (HQ) from inhalation of PAHs present in the indoor air of local canteens are lower than WHO and USEPA permissible limit. Although local restaurants and canteens across Ado Ekiti pose no significant risk to human health on short-term exposures with regards to PAH inhalation. However continuous exposure to these pollutants in these indoor environments is of great concern.

Emissions monitoring and carcinogenic risk assessment of PM10-bounded PAHs in the air from Candiota's coal activity area, Brazil.

The city of Candiota contains a great amount of coal resources. Coal activities, including coal combustion, are major releasers of polycyclic aromatic hydrocarbons (PAHs). The PAHs are considered priority air pollutants regarding their large carcinogenic potential. So, the carcinogenic risk assessment of populations living near areas with PAH sources is mandatory. This study aimed to evaluate the carcinogenic health risk of the PAH inhalation exposure of individuals living in Candiota City. A total of 158 individuals were enrolled in the study. Monitoring of PAH and meteorological parameters were carried out, and the health risk assessment was determined through the benzo(a)pyrene equivalent toxic equivalent quotient (BaP-TEQ) and the incremental lifetime cancer risk (ILCR) estimation. The coal activity area of Candiota demonstrated an annual PAH concentration of 27.7ng/m3, PM10 concentration of 26.3µg/m3, SO2 concentration of 9.5µg/m3, a BaP-TEQ value of 0.3ng/m3, and a daily inhalation of 62.4ng/day. The comparison among seasons showed no difference in PAH concentration and BaP-TEQ. It was observed ILCR values of 2.8 × 10-6 and 2.6 × 10-6 for estimation based on reference and real values, respectively, and these levels were above the reference limit of 10-6, indicating cancer risk. Therefore, an epidemiological survey of cancer cases in the region and its relationship with environmental exposure and air pollutants levels must be required.

Health risk assessment of exposure to polycyclic aromatic hydrocarbons in household indoor environments

Airborne particles are able to transport the potentially mutagenic and carcinogenic compounds adsorbed to their surfaces, such as polycyclic aromatic hydrocarbons (PAHs). As a result, they can affect human health and, consequently, the quality of life. In the present paper, we analyzed household airborne particles and estimated the human health risk due to PAH inhalation. Households from Cordoba city (Argentina) were selected for collecting weekly samples of total suspended particles, fine particles (> 2.5 µm) and submicron particles (< 1 µm) during a one-month period in both winter and summer. We found differences in the PAH composition among the three particle sizes, with the PAH levels being particularly high during summer for all three fractions, probably due to pollutants coming from outside or the persistence of pollutants inside homes. In addition, urban households had higher PAH levels than suburban houses. However, the calculated health risks due to the inhalation of particles never exceeded the levels recommended by the Environmental Protection Agency of the United States (< 1 in 10,000) for any age group. Our results, despite the relatively small number of houses included in the study, provide an indication of the likely exposure range of the population in urban environments of developing countries.

Emission reduction of black carbon and polycyclic aromatic hydrocarbons during COVID-19 pandemic lockdown.

The global pandemic COVID-19 necessitated various responses throughout the world, including social distancing, use of mask, and complete lockdown. While these measures helped prevent the community spread of the virus, the resulting environmental benefits of lockdown remained mostly unnoticed. While many studies documented improvements in air quality index, very few have explored the reduction in black carbon (BC) aerosols and polycyclic aromatic hydrocarbons (PAHs) concentrations due to lockdown. In this study, we evaluated the changes in concentrations of BC, PAHs, and PM2.5 before and during the lockdown period. Our results show that lockdown resulted in a significant reduction in concentrations of these pollutants. The average mass concentration of BC, PAHs, and PM2.5 before the lockdown was 11.71 ± 3.33 μgm−3, 108.71 ± 27.77 ngm−3, and 147.65 ± 41.77 μgm−3, respectively. During the lockdown period, the concentration of BC, PAHs, and PM2.5 was 2.46 ± 0.95 μgm−3, 23.19 ± 11.21 ngm−3, and 50.31 ± 11.95 μgm−3, respectively. The diagnostic ratio analysis for source apportionment showed changes in the emission sources before and during the lockdown. The primary sources of PAHs emissions before the lockdown were biomass, coal combustion, and vehicular traffic, while during the lockdown, PAHs emissions were primarily from the combustion of biomass and coal. Similarly, before the lockdown, the BC mass concentrations came from fossil-fuel and wood-burning, while during the lockdown period, most of the BC mass concentration came from wood-burning. Human health risk assessment demonstrated a significant reduction in risk due to inhalation of PAHs and BC-contaminated air.

Nationwide increase of polycyclic aromatic hydrocarbons in ultrafine particles during winter over China revealed by size-segregated measurements

Abstract. Polycyclic aromatic hydrocarbons (PAHs) are toxic compounds in the atmosphere and have adverse effects on public health, especially through the inhalation of particulate matter (PM). At present, there is limited understanding of the size distribution of particulate-bound PAHs and their health risks on a continental scale. In this study, we carried out a PM campaign from October 2012 to September 2013 at 12 sampling sites simultaneously, including urban, suburban and remote sites in different regions of China. Size-segregated PAHs and typical tracers of coal combustion (picene), biomass burning (levoglucosan) and vehicle exhaust (hopanes) were measured. The annual averages of the 24 total measured PAHs (∑24PAHs) and benzo[a]pyrene (BaP) carcinogenic equivalent concentration (BaPeq) ranged from 7.56 to 205 ng/m3 with a mean of 53.5 ng/m3 and from 0.21 to 22.2 ng/m3 with a mean of 5.02 ng/m3, respectively. At all the sites, ∑24PAHs and BaPeq were dominant in the ultrafine particles with aerodynamic diameter &lt; 1.1 µm, followed by those in the size ranges of 1.1–3.3 µm and &gt; 3.3 µm. Compared with southern China, northern China witnessed much higher ∑24PAHs (87.36 vs. 17.56 ng/m3), BaPeq (8.48 vs. 1.34 ng/m3) and PAHs' inhalation cancer risk (7.4 × 10−4 vs. 1.2 × 10−4). Nationwide increases in both PAH levels and inhalation cancer risk occurred in winter. The unfavorable meteorological conditions and enhanced emissions of coal combustion and biomass burning together led to severe PAHs' pollution and high cancer risk in the atmosphere of northern China, especially during winter. Coal combustion is the major source of BaPeq in all size particles at most sampling sites. Our results suggested that the reduction of coal and biofuel consumption in the residential sector could be crucial and effective in lowering PAH concentrations and their inhalation cancer risk in China.

Indoor levels of polycyclic aromatic hydrocarbons (PAHs) from environment tobacco smoke of public bars

In this work level of Polycyclic Aromatic Hydrocarbon (PAHs) from indoor Environment Tobacco Smoke (ETS) of pubic bars in Nigeria was investigated. Indoor air samples were obtained from different public bars using Polyurethane foam (PUF) passive samplers. Analysis of PAHs was carried out using GC-MS operated in selected ion monitoring mode. Result showed the average concentration range of 2.71–9.69 ng/m3 while the ∑ 16 PAHs range from 43.43 to 155.11 ng/m3. The incremental lifetime cancer risk (ILCR) values from inhalation of PAHs in these bars ranged from 2.4×10−7−5.2×10−7 while non-carcinogenic risk, Hazard Quotient (HQ) ranged from 2×10−4−4.5×10−4. Although these values are lower than WHO permissible limit, nevertheless the study underscores the danger associated with the inhalation of ETS in the public bars in Nigeria.

Exposure and Absorption of PAHs in Wildland Firefighters: A Field Study with Pilot Interventions.

ObjectivesThere is limited knowledge of exposure to polycyclic aromatic hydrocarbons (PAHs) in wildland firefighters, or of the effectiveness of interventions to reduce this. This study of wildland firefighters assessed whether PAHs were present and considered respiratory protection and enhanced skin hygiene as possible interventions.Methods1-Hydroxypyrene (1-HP) was measured in urine samples collected pre-shift, post-shift, and next morning from wildland firefighters in Alberta and British Columbia. Skin wipes, collected pre- and post-shift, were analysed for eight PAHs. Breathing zone air samples were analysed for 11 PAHs. As pilot interventions, participants were randomized to either normal or enhanced skin hygiene. A sample of volunteers was assigned to a disposable N95 mask or a half facepiece mask with P100 organic vapour cartridge. Participants completed a brief questionnaire on activities post-shift and respiratory symptoms.ResultsNon-smoking firefighters (66 male and 20 female) were recruited from 11 fire crews. Air sampling pumps were carried for the full shift by 28 firefighters, 25 firefighters wore masks (14 N95 and 11 P100); 42 were assigned to the enhanced skin hygiene intervention. Sixty had hot spotting as their main task. Air monitoring identified PAHs (benzo(b,j,k)fluoranthene in particulates, phenanthrene in the gaseous phase) for 6 of the 11 crews. PAHs (largely naphthalene) were found post-shift on 40/84 skin wipes from the hand and 38/84 from jaw/throat. The mean increase in 1-HP in urine samples collected after the shift (compared with samples collected before the shift) was 66 ng g−1 creatinine (P < 0.001) with an increase over the shift found for 76% of participants. 1-HP in next morning urine samples was significantly lower than at the end of shift (a reduction of 39.3 ng g−1: P < 0.001). The amount of naphthalene on skin wipes was greater at the end of the shift (post) than at the start (pre). The mean post–pre weight difference of naphthalene on skin wipes taken from the hand was 0.96 ng wipe−1 (P = 0.01) and from the jaw/throat 1.28 ng wipe−1 (P = 0.002). The enhanced skin hygiene intervention lead to a larger reduction in 1-HP between end of shift and next morning urine samples but only for those with naphthalene on skin wipes at the end of shift. The difference in 1-HP concentration in urine samples collected before and after the shift was reduced for those wearing a mask (linear tend P = 0.063, one-sided). In multivariable models, 1-HP at end of shift was related to gaseous phase phenanthrene, estimated from air sampling [β = 318.2, 95% confidence interval (CI) 67.1–569.2]. Naphthalene on hand skin wipes reflected work in hot spotting during the shift (β = 0.53, 95% CI 0.22–0.86).ConclusionsThis study provided evidence of PAHs in the air and on the skin of many, but not all, fire crew. Absorbed PAHs, reflected in 1-HP in urine, increased over the shift. Results from the pilot interventions suggest that enhanced skin hygiene would reduce absorption post fire where PAHs had been accumulated on the skin, and that masks could be effective in reducing PAH inhalation exposure. Interventions to reduce PAH absorption are supported by the pilot work reported here and warrant further evaluation across a full fire season.

Sources apportionment and carcinogenic risk of polycyclic aromatic hydrocarbons in gas phase of urban Shanghai: Based on high volume solid phase extraction (Hi-volume SPE).

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants, posing potentially serious threats to human health. This study analyzed compositional characteristics, sources, and carcinogenic risks of PAHs in the atmospheric gas phase at an urban site in Shanghai, East China. Seventy-four gas phase samples were collected during the warm months of May-October 2018 using a high-volume solid phase extraction (Hi-volume SPE) technique. The total concentration of sixteen priority PAHs (ΣPAHs) was in the range of 5.54-182.05ngm-3 (average 34.47ngm-3) and the total of seven carcinogenic PAHs (ΣCPAHs) was in range of 0.03-1.49ngm-3 (average 0.48ngm-3), accounting for 1.47% of ΣPAHs and indicating low carcinogenic potential. Redundancy analyses indicated positive correlations between ΣPAHs and air quality, and ΣCPAHs and average high temperature, and a negative correlation between ΣPAHs and wind speed. Four possible sources, namely petroleum and petrogenic sources, traffic emissions, coal combustion, and mixed gasoline and coal combustion sources, were identified by positive matrix factorization (PMF), accounting for 62.84%, 19.31%, 10.15%, and 7.69% of ΣPAHs, respectively. The overall lifetime lung cancer risk (LLCR) through inhalation of PAHs was estimated to be at a low risk level of 1.61×10-5. The LLCR based on PMF apportionment decreased in the order of mixed gasoline and coal combustion sources (47.07%)>traffic emissions (35.10%)>petroleum and petrogenic sources (11.06%)>coal combustion (6.74%). This study demonstrates the effectiveness of Hi-volume SPE in collecting and analyzing atmospheric gas phase PAHs.

Organic chemical characterization of size segregated particulate matter samples collected from a thermal power plant area

Kütahya city, a thermal power plant (TPPs) affected region of Turkey, has serious air quality problems like similar industrial regions of the world due to the emissions from three closely-located coal-fired TPPs, residential coal combustion along with the contribution of several industrial stacks. The organic chemical speciation of ambient size-segregated particulate matter (PM) was investigated during two seasons at two sites with different pollution characteristics (urban and rural). The ambient PM was collected using a high volume cascade impactor, with 6 stages: PM>10.2, PM10.2-4.2, PM4.2-2.1, PM2.1-1.3, PM1.3-0.69 and PM<0.69. Collected PM samples were extracted with organic solvents and the organic composition (Polycyclic aromatic hydrocarbons (PAHs), n-alkanes and carboxylic acids) was determined by GC-MS. Sources of the organic species were assessed using molecular PAH diagnostic ratios, carbon preference index and wax percentages. More than 70% of the PM-bound PAHs were quantified in submicron particles. Similarly, 34–42% of n-alkanes and approximately 30% of the carboxylic acids were found on the smallest particles. The main sources of the PM-bound organic species were considered as the anthropogenic emissions such as coal and biomass combustion and also vehicular emissions rather than the biogenic sources. Considerably high cancer risk levels were obtained through inhalation of PAHs. Seasonal variations and size distributions of the carboxylic acids and levoglucosan were also evaluated. Polar organic compound concentrations were higher in the summer period at both locations probably due to the higher sunlight intensity and temperature favoring their photochemical formation.

Carcinogenic risk from exposure to PM2.5 bound polycyclic aromatic hydrocarbons in rural settings.

In the study, first-time personal exposure level of polycyclic aromatic hydrocarbons (PAHs) was measured during cooking hours in participants of three different types of kitchen both in the particulate and gaseous phase using traditional and improved cookstoves. Along with that, indoor particulate matter (PM) concentration was also estimated during the cooking hours to examine the impact of intervention in different kitchens. The results of the study clearly revealed that the kitchen characteristics and type of cookstove technology have a significant impact on PM2.5, PM1 and PAHs concentration. Cookstoves intervention has resulted in maximum reduction of PM1 i.e. 75% in an enclosed kitchen followed by semi-enclosed and open kitchen having 71% and 52%, respectively. In addition, correlation analysis of PM2.5 and PM1 with PAHs showed a strong association (r2=0.9), showing the affinity of PAHs to bind to fine range of particles. Health risk assessment was also carried out to assess the PM daily dose and carcinogenic and non-carcinogenic risk due to inhalation of PAHs. The study confirmed the personal concentration of PAHs compounds was significantly high (p<0.05) during use of traditional cookstove compared to improved cookstove among all the three kitchens. Furthermore, to measure the toxicity levels, PAHs concentrations have been converted to benzo[a]pyrene equivalence for calculating cancer and non-cancer effects using toxicity equivalency factors. The overall lifetime carcinogenic risk was the highest 2.5E-03, 6.4E-04 among women who prepared meals in the enclosed kitchen compared to 8.4E-04, 1.3E-04 in semi-enclosed and 2.2E-04, 4.6E-05 in the open kitchen during use of traditional and improved cookstoves, respectively, which exceeded the US EPA standard i.e. 1×10-6. The study underlined the importance of personal monitoring for exposure, and risks-based studies along with the time-activity of user to measure the actual inhalation risk for the participants. These findings indicated that women are exposed to hazardous smoke in the indoor kitchen and are at greater risk of developing cancer, especially in rural areas.

A comprehensive study on gas and particle emissions from laser printers: Chemical composition and health risk assessment

In this study, a general evaluation of indoor air quality (IAQ) in an office room with intense printing activity was investigated. Instantaneous peaks of PM2.5 and O3 were observed when the printer was working, and the concentrations were decreased significantly on idle times. Size distribution of PM showed a remarkable contribution of quasi-ultrafine mode particles to the total aerosol mass. Polycyclic aromatic hydrocarbons (PAHs) and elemental carbon (EC) occupied an insignificant percent of the aerosol mass, while organic carbon (OC) together with elements were noted to be significant. Carcinogenic and non-carcinogenic health risks due to the PM exposure were evaluated by using size-dependent deposition fractions in the respiratory tract. Hazard index (HI) was calculated as 5.5 × 10−5 for the PAHs and 2.2 × 10−1 for heavy metal exposure as the sum of inhalation, ingestion and dermal exposures. Cancer risk (CR) values were obtained to be 6.3 × 10−7 and 6.4 × 10−6 for the inhalation of PAHs and heavy metals, respectively. As a result of the higher concentration of the VOCs, total CR higher than 1.3 × 10−5 was estimated, while total hazard quotient (HQ) value was noticed to be 9.9 × 10−2 in the office.

Characterization and Health Risk Assessment of Human Exposure to PAHs in Dust Deposited on Leaves of Street Trees in Egypt

Dust deposited on leaves of trees can be effectively used as monitors of polycyclic aromatic hydrocarbons (PAHs). Sixteen EPA priority PAHs concentrations in deposited dust on leaves of the street trees (leaves dust) at 14 sampling sites at traffic and residential areas in Cairo, Egypt were measured. The health risk of the 16 PAHs to humans were estimated and calculated. Results indicate that the predominant PAHs were high molecular weight-PAHs, with higher contribution 83%, whereas low molecular weight-PAHs were the less lower contribution 17%. Higher concentrations of ΣPAHs recorded at traffic areas (18,223 ± 4,172) mg/kg, whereas lower levels were found in residential areas (8,261 ± 2,006) mg/kg. The diagnostic ratios and total indexes of PAHs compounds indicate that traffic emissions and incomplete combustion were the major sources of PAHs in deposited dusts on leaves of street trees of Greater Cairo. The health risk assessment focused on ΣPAHs in leave dust, which were related to health impacts. The results recorded higher exposure doses at traffic areas than residential areas. In the current study, hazard quotient and hazard indices values were less than 1 at all sampling sites, indicating that there were no health effects for noncarcinogen. The cancer risk values for inhalation of PAHs in traffic areas > residential areas for child and adult. The current results showed that the cancer risk values were within the safe levels set by United States Environmental Protection Agency. These results indicate that cancer risk values for Greater Cairo were within the acceptable range, implying negligible carcinogenic risk.

Health risk assessment of PAHs, PCBs and OCPs in atmospheric air of municipal solid waste landfill in Novi Sad, Serbia

The municipal solid waste landfill in Novi Sad, Serbia is in its operative status from early 1980s and represents potential significant source of environmental compartments pollution and the threat to human health as a result of undeveloped waste management practice. Residues of Polycyclic Aromatic Hydrocarbons (PAHs) and Persistent Organic Pollutants (POPs) as toxic, mutagenic, teratogenic and carcinogenic chemicals were investigated in ambient air of landfill site in Novi Sad. Passive air sampling technique was used for the purpose of ambient air sampling. Total risk to the human health is calculated as a sum of individual risks for each group of substances according to the recommended United States Environmental Protection Agency (US EPA) methodology. The overall results indicate that the landfill site in Novi Sad does not pose a relevant treat to human by inhalation of PAHs and POPs. The effect of low concentrations, non-monotonic dose response, synergistic and amplifying effects of chemical complexes must be highly respected while performing future health risk assessment.

Chemical profiling of PM10 from urban road dust

Road dust resuspension is one of the main sources of particulate matter with impacts on air quality, health and climate. With the aim of characterising the thoracic fraction, a portable resuspension chamber was used to collect road dust from five main roads in Oporto and an urban tunnel in Braga, north of Portugal. The PM10 samples were analysed for: i) carbonates by acidification and quantification of the evolved CO2, ii) carbonaceous content (OC and EC) by a thermo-optical technique, iii) elemental composition by ICP-MS and ICP-AES after acid digestion, and iv) organic speciation by GC–MS. Dust loadings of 0.48±0.39mgPM10m−2 were obtained for asphalt paved roads. A much higher mean value was achieved in a cobbled pavement (50mgPM10m−2). In general, carbonates were not detected in PM10. OC and EC accounted for PM10 mass fractions up to 11% and 5%, respectively. Metal oxides accounted for 29±7.5% of the PM10 mass from the asphalt paved roads and 73% in samples from the cobbled street. Crustal and anthropogenic elements, associated with tyre and brake wear, dominated the inorganic fraction. PM10 comprised hundreds of organic constituents, including hopanoids, n-alkanes and other aliphatics, polycyclic aromatic hydrocarbons (PAH), alcohols, sterols, various types of acids, glycerol derivatives, lactones, sugars and derivatives, phenolic compounds and plasticizers. In samples from the cobbled street, these organic classes represented only 439μgg−1PM10, while for other pavements mass fractions up to 65mgg−1PM10 were obtained. Except for the cobbled street, on average, about 40% of the analysed organic fraction was composed of plasticizers. Although the risk via inhalation of PAH was found to be insignificant, the PM10 from some roads can contribute to an estimated excess of 332 to 2183 per million new cancer cases in adults exposed via ingestion and dermal contact.

Polycyclic aromatic hydrocarbons in the urban atmosphere of Nepal: Distribution, sources, seasonal trends, and cancer risk

Atmospheric polycyclic aromatic hydrocarbons (PAHs) in urban areas have always been a global concern, as these areas are considered to be the source region. Despite studies on the concentrations of PAHs in water, soils and sediments, knowledge of the distribution patterns, seasonality and sources of PAHs in urban areas of Nepal remains limited. In this study, polyurethane foam passive air samplers were used to measure gas-phase PAH concentrations over different land types in three major cities of Nepal—namely, Kathmandu (the capital) and Pokhara (both densely populated cities), and Hetauda (an agricultural city). The average concentrations of ∑15PAHs in ng/m3 were 16.1±7.0 (6.4–28.6), 14.1±6.2 (6.8–29.4) and 11.1±9.0 (4.1–38.0) in Kathmandu, Pokhara and Hetauda, respectively. Molecular diagnostic ratio analysis suggested that fossil fuel combustion was a common PAH source for all three cities. In addition to this, coal combustion in Kathmandu, vehicle emissions in Pokhara, and grass/wood combustion in Hetauda were also possible sources of PAHs. In terms of cancer risk from PAH inhalation, a religious site with intense incense burning, a brick production area where extensive coal combustion is common, and a market place with heavy traffic emission, were associated with a higher risk than other areas. There were no clear seasonal trends in atmospheric PAHs. The estimated cancer risk due to inhalation of gas-phase PAHs exceeded the USEPA standard at >90% of the sites.

Levels and risk factors for urinary metabolites of polycyclic aromatic hydrocarbons in children living in Chongqing, China

AimsSince childhood exposure to polycyclic aromatic hydrocarbons (PAHs) have been associated with a variety of adverse health outcomes, the aims of this study were to1) document PAH exposure levels among children in Chongqing, China by measuring urinary concentrations of four PAH metabolites, 1-hydroxypyrene (1-OHPyr), 2-hydroxynaphthalene (2-OHNap), 2-hydroxyfluorine (2-OHFlu) and 9-hydroxyphenanthrene (9-OHPhe), and 2) assess the associations of urinary concentrations of these PAH metabolites with risk factors related to sources of PAHs inhalation and ingestion exposures and with personal attributes such as sex, age, and BMI. MethodsThe present study is a cross-sectional analysis using data drawn from the third follow up of a longitudinal study. Purposive sampling was used with all students in grades one to four in four schools being eligible to participate. The baseline survey included a total of 1237 students 5.8 to 12.2years of age. At the third follow up survey, 1.5years after the baseline survey, 1230 of the children had a physical exam and provided urine samples. Their parents completed a questionnaire including social-demographic information and possible sources of children's exposure to PAHs. Urine samples were measured for the four OH-PAHs using an HPLC-MS/MS technique. Concentrations were corrected by specific gravity. Linear regression analysis was used to investigate factors related to sources of PAHs exposure. ResultsThe urinary concentrations were highest for 9-OHPhe (median at the range of 3661ng/L), followed by 2-OHNap (3189ng/L), 2-OHFlu (1116ng/L), and 1-OHPyr (250ng/L). In multiple linear regressions, being female (P=0.04), school location near a thermal power plant (P=0.02) and higher maternal age at birth (P<0.01) were associated with increased concentrations of urinary 1-OHPyr; no significant associations were found for 2-OHNap; school location near a thermal power plant (P<0.01) and lower family income (P<0.01) were associated with increased concentrations of urinary 2-OHFlu; higher age (P<0.01), school location near a thermal power plant (P=0.01), frequent consumption of smoked foods (P=0.04) and lower family income (P=0.07) were all found to be associated with increased concentrations of 9-OHPhe. ConclusionsUrinary concentrations of OH-PAHs, especially 9-OHPhe, were elevated in Chongqing Children compared to children in other countries. Being female, older age, school location near an industrial site, frequent consumption of smoked foods and lower family income were all associated with higher OH-PAHs concentrations. Further cohort studies are needed to confirm the associations between potential exposure sources and children's exposure to PAHs, in order to provide recommendations to reduce exposure.