Average Concentration Of Total Polycyclic Aromatic Hydrocarbons Research Articles

Assessment of soil pollution with polycyclic aromatic hydrocarbons in Ulan-Ude

: For the first time, polycyclic aromatic hydrocarbons (PAH) contamination of the soil cover of Ulan-Ude, the capital of the Republic of Buryatia, was studied. The content of 16 individual polyarenes was analyzed in the upper horizon of background chestnut and urban soils, sampled during soil and geochemical survey in July–August 2022. The average concentration of total PAHs in the soil cover of Ulan-Ude was 735 ng/g, which was 8 times as much as the concentration in the background soils (87 ng/g). The PAH amount in the soil of various functional zones decrease in the following order: railway transport > motor traffic > industrial > one-story residential > multi-story residential > recreational. At the same time, the amount of PAHs in the railway transport zone was 2.6–5.2 times higher than in other functional zones, which indicates that railway transport is the most powerful source of PAHs in the city. Contamination of soils with polyarenes in all functional zones is determined primarily by medium- (46%) and high-molecular-weight (41%) compounds. Among PAHs with low molecular weight, phenanthrene prevailed (9% of the total PAHs), but medium-molecular-weight fluoranthene (18%) and pyrene (13%) showed higher share; high-molecular-weight compounds dominated by benzo(ghi)perylene (12%), benzo(b)fluoranthene (10%), indeno(1,2,3-cd)pyrene (8%) and benzo(a)pyrene (6%). The total amount of 16 PAHs in the soil cover of the city varied within the range of 17–9 540 ng/g. The highest levels of pollution (3 226–9 540 ng/g) were recorded at 9 sampling points (4% of the city), which form the most contrasting local PAH anomalies. In more than half of the territory of Ulan-Ude, the total amount of PAHs did not exceed 500 ng/g. The indicator ratios of individual PAHs made it possible to determine the dominant types of sources, which include railway transport and coal combustion. The contribution to the environmental hazard of soil contamination with PAHs in Ulan-Ude was mainly made by benzo(a)pyrene (64%) and, to a lesser extent, by benzo(b)fluoranthene (9.6%), indeno(1,2,3-cd)pyrene (7.2%), dibenzo(ah)anthracene (6.5%) and benzo(a)anthracene (6.1%).

Characteristics, sources, and health risks of PAHs and their derivatives in indoor dust in Zhengzhou

The occurrence, source, and health risk of polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs (NPAHs), and oxy-PAHs (OPAHs) in indoor dust collected from three types of microenvironments (offices, classrooms, and dormitories) at a university campus in Zhengzhou were analysed. The results showed that the average concentration of the total PAHs was 2403.21 ± 981.99 ng g−1, with PHE (20.06% of Σ18PAHs) and BkF (15.46%) being the dominant species. The average concentrations of total NPAHs and OPAHs were 11.09 ± 5.12 and 385.80 ± 255.27 ng g−1, with 2+3N-FLT (39.15%) and 9-FLO (39.76%) as the most abundant species of NPAHs and OPAHs, respectively. The average concentrations of total PAHs, NPAHs, and OPAHs in different microenvironments displayed obvious spatial specificity with the highest values in dormitories. The main source of PAHs, as identified by diagnostic ratios, was petroleum combustion, coal/biomass combustion and vehicle exhaust emissions. The average incremental lifetime cancer risk (ILCR) for undergraduates exposed to dust in classrooms and dormitories exceeded 10−6, indicating a potential cancer risk. The most important exposure pathway was dermal contact, while the inhalation route was negligible.

Polycyclic aromatic hydrocarbons (PAHs) in fish (Clarias gariepinus) of southwestern rivers, Nigeria: Occurrence, distribution, and potential human exposure risks

This study was undertaken to analyze Polycyclic aromatic hydrocarbons (PAHs) in fish (Clarias gariepinus) from six major rivers within southwest Nigeria to assess the ecotoxicological and human health risks. The average concentrations of total PAH (∑PAH) ranged from 12.18 to 49.12 µg/g and from 10.35 to 38.09 µg/g during the dry and wet seasons, respectively, and the ranges were significantly higher than the prescribed WHO (0.001 µg/g) and European Union (0.002 µg/g) recommended safe levels for human consumption. The low molecular weight PAHs (2–3 rings) dominated the profile, suggesting petrogenic sources. Phenanthrene remains the highest contributor to PAH intake across all locations and seasons. The toxicity equivalent quotients (TEQ), which represents the sum of B(a)P equivalent concentration [B(a)Peq] ranged from 0.851 to 2.014 μg BaP/g with a slightly higher range of 1.046–2.763 μg BaP/g during the dry and wet seasons, respectively. Across both seasons, the estimated hazard quotient (HQ) and hazard index (HI) were found to be < 1, suggesting consumption of Clarias gariepinus has no non-carcinogenic risks. The estimated excess cancer risk value (1.55×10−2 to 5.03×10−2) from consumption of C gariepinus exceeded all regulatory guideline values for potential cancer risk. The excess cancer risk, predominated by B(a,h)A (0.0194 µg/g) and B(a)P (0.0163 µg/g) suggests a greater risk of exposure during the wet season. The study showed no human health risk due to PAHs in Clarias gariepinus obtained from southwestern rivers in Nigeria. However, due to bioaccumulation, policies that will ensure regular monitoring of PAHs in seafood are recommended to maintain a sustainable ecosystem.

Pollution Characteristics and Risk Assessment of PAHs in the Soil of Wild Forsythia Suspensa in Shanxi

Shanxi is one of the main producing areas of Forsythia suspensa in China. In order to explore the safety of the soil in the areas where Forsythia suspensa grows,70 surface (0-25 cm) soil samples were collected from the main growing areas of F. suspensa in the eastsouth of Shanxi Province in July 2017. The concentration and composition characteristics of 16 polycyclic aromatic hydrocarbons (PAHs) in the sample soils were analyzed using chemical extraction and gas chromatography-mass spectrometry (GC-MS). The diagnostic ratio method was used to determine the source of PAHs in the areas. The potential ecological risk was assessed by using the method of calculating the equivalent carcinogenic concentration of benzo[a]pyrene. The results showed that the average concentration of total PAHs (Σ16PAHs) in all of the soil samples was 1.85 μg·g-1, which was dominated by three ring number PAHs, accounting for 76.7% of the total PAHs. The detection rates of phenanthrene (Phe) and anthracene (Ant) were both 100% of all the sample sites. The soil PAHs in the wild F. suspensa growing areas mainly originated from coal, biomass burning, and motor vehicle exhaust emissions, which resulted from air transport and sedimentation pathways. In all of the sample sites, the concentration of Σ16PAHs the limit standard level (0.2 μg·g-1) of Maliszewska-Kordybach for agricultural soil pollution and exceeded the soil heavy pollution level limit value (1.0 μg·g-1) in 41.4% of the sample sites. The concentration of BaP was above the risk control standard for soil contamination of agricultural land (0.55 μg·g-1) in 10% of all the soil samples. A total of 11.4% of the sample soil ΣBaPeq16PAHs and ΣBaPeq8BPAHs exceeded the agricultural soil screening value (0.55 μg·g-1). These results indicate that the contamination of PAHs was at a detectable level in the soil of wild F. suspensa growing in Shanxi, and thus their potential ecological risks should not be ignored. It is necessary to enhance the research regarding these areas to ensure the safe production of medicinal plants.

Emission and distribution profiles of polycyclic aromatic hydrocarbons in solid residues of municipal and industrial waste incinerators, Northern Vietnam.

The concentrations and profiles of 18 polycyclic aromatic hydrocarbons (PAHs) in particulate matter (PM10), fly ash (FA), and bottom ash (BA) were examined in three incineration residues. Samples were collected from different municipal and industrial solid waste incinerators in Northern Vietnam. The average concentrations of total PAHs in PM10, fly ash, and bottom ash were 9.55 × 103ng/Nm3, 215 × 103ng/g, and 2.38ng/g, respectively. Low-molecular-weight PAHs (2 to 3 rings) were predominant in most samples. The emission factor of total PAHs decreased in the order of FA > BA > PM10. A higher concentration of total PAHs was found in industrial facilities than that in municipal ones. The high carcinogenic proportion of PAHs together with significantly high annual emissions reflect the high pollution risk to the ecosystem by PAHs in the case of reuse of incineration ashes (e.g., brick production). Regarding the carcinogenic risk of PAH-bounded ashes or particles, calculations from this study imply the significant threat for workers who have been manipulated in the incineration facilities, directly exposed to fly and bottom ashes. Meanwhile, the risk from PAH-bound particulate was not considered a significant threat for both normal adults and children. Further study on PAHs contained in incinerator waste dumps should be conducted in Vietnam to assess the potential contamination risk of these incineration by-products.

New perspective on human health risk from polycyclic aromatic hydrocarbons (PAHs) on surfaces of structures and buildings for industrial legacy before and after remediation

Industrial legacies are gradually becoming an important asset for urban regeneration. Coking plants, as one of the important industrial legacies, emit large amounts of polycyclic aromatic hydrocarbons (PAHs) in production, and the health risks of PAHs in the atmosphere and soil around coking plants have been fully recognized, but not much attention has been paid to the health risks of PAHs adsorbed on the surfaces of buildings. Therefore, we evaluated the health risks of PAHs adsorbed on the surfaces of buildings before and after the remediation and relocation of a legacy coking plant in China. Remediation was done in three steps: (1) mechanical grinding, (2) high-pressure blasting, and (3) surfactant washing. The concentration of total PAHs and the distribution of PAHs before remediation were different for each structure. The average total PAHs concentration before remediation was found to be between 0.16 mg m−2 and 329.77 mg m−2. The risk posed by the PAHs concentrations before and after remediation in each structure was quantified. For workers, surrounding residents, and tourists, the calculated carcinogenic risk ranged from 1.08 × 10−6 to 6.84 × 10−4, 9.00 × 10−6 to 4.89 × 10−3, and 7.44 × 10−6 to 3.22 × 10−3, respectively. After remediation, total PAHs concentrations ranged from non-detect to 1.15 g m−2. Our research has shown that PAHs adsorbed on the surface of coking plant buildings can pose serious health risks to human and require remediation before reuse. Mechanical grinding, high-pressure blasting, and surfactant cleaning can effectively remove PAHs adsorbed on the surface of buildings. The above results would provide different perspectives for the site risk assessment and remediation before the industrial legacies were reused.

Analysis of gaseous polycyclic aromatic hydrocarbon emissions from cooking devices in selected rural and urban kitchens in Bomet and Narok counties of Kenya.

Traditional combustion devices and fuels such as charcoal, wood and biomass, are widely utilised in rural and urban households in Africa. Incomplete combustion can generate air pollutants which are of human toxicological importance, including polycyclic aromatic hydrocarbons (PAHs). In this study, portable multi-channel polydimethylsiloxane rubber traps were used to sample gas phase emissions from cooking devices used in urban and rural households in Bomet and Narok counties of Kenya. A wide range of total PAH concentrations was found in samples collected (0.82 - 173.69 µg/m3), which could be attributed to the differences in fuel type, combustion device, climate, and nature of households. Wood combustion using the 3-stone device had the highest average total PAH concentration of ~71 µg/m3. Narok had higher indoor total gas phase PAH concentrations averaging 35.88 µg/m3 in urban and 70.84 µg/m3 in rural households, compared to Bomet county (2.91 µg/m3 in urban and 9.09 µg/m3 in rural households). Ambient total gas phase PAH concentrations were more similar (Narok: 1.26 - 6.28 µg/m3 and Bomet: 2.44 - 6.30 µg/m3). Although the 3-stone device and burning of wood accounted for higher PAH emissions, the charcoal burning jiko stove produced the highest toxic equivalence quotient. Monitoring of PAHs emitted by these cooking devices and fuels is critical to public health and sustainable pollution mitigation.

Contamination Assessment of Mangrove Ecosystems in the Red Sea Coast by Polycyclic Aromatic Hydrocarbons.

Mangroves are known as a naturally based solution for climate mitigation and adaptation. Mangroves are at a potential risk of degradation by contaminants such as polycyclic aromatic hydrocarbons (PAHs). In this study, sixteen priority PAHs were analyzed and characterized in forty samples of mangrove seawater and mangrove sediments collected from two coastal areas (i.e., Sharm and Khor Rabigh) along the Red Sea Coast of Rabigh city in August 2013. We found that the average concentration of total PAH in mangrove sediments in the Sharam area (22.09 ng/kg) was higher than that in the Alkhor area (6.51 ng/kg). However, the average concentration of the total PAH in the mangrove seawater in the Alkhor area (9.19 ng/L) was double that in the Sharam area (4.33 ng/L). Phenanthrene and pyrene were the major components in both the mangrove seawater and sediment in all the investigated areas. We observed that the abundance of PAHs with 2–3 aromatic rings was dominant in sediment samples collected from both study areas. This abundance was also observed in seawater from the Sharam area. However, seawater samples from the Alkhor area had abundant PAHs with four aromatic rings. The majority of PAHs in sediment samples of both study areas originated from petrogenic sources, whereas the majority of PAHs in seawater samples originated from pyrogenic sources.

Concentrations, sources, and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in black, green and fruit flavored tea in Turkey

This study was performed to identify the levels and possible sources of EPA priority PAHs in different types of commercially sold and consumed tea samples in Turkey. Health risk related to PAHs exposure due to tea consumption was also estimated. The average total PAH concentrations were measured as 317.0, 352.3, and 452.3 μg/kg for 25 black, three green, and 12 flavored Turkish tea samples. The results showed that 3- and 4-ring PAHs were the predominant groups for all tea samples. Factor analysis was utilized to identify the source characteristics of PAHs in tea samples. The results indicated that emissions from direct contact during transport and storage of tea leaves have significant impacts in addition to those from thermal processing during production. The estimated lifetime cancer risks ranged from 4.4 × 10−5 to 2.0 × 10−4 for all tea samples, indicating low-to-moderate risks for consumers of these tea products. All the estimated cancer risk values for PAHs in this study were higher than permissible risk levels, while three flavored tea samples were higher than the acceptable risk levels specified by US EPA.

Distribution and Potential Sources of OCPs and PAHs in Waters from the Danshui River Basin in Yichang, China.

To investigate the concentrations, spatial distribution, potential sources and mass fluxes of organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs) in waters from the Danshui River Basin, a total of 20 water samples were collected and analyzed from a karstic river in Western Hubei of Central China. The average concentrations of total OCPs and PAHs in the river water were 4719 pg·L−1 and 26.2 ng·L−1, respectively. The characteristic ratios of different isomers and the composition analysis of individual OCPs and PAHs revealed that HCHs originated from a mixed input of technical HCHs and Lindane, DDTs were mainly from technical DDTs, and PAHs mainly originated from biomass and coal combustion. The mass flux analysis showed that PAHs had a higher emission and heavier burden than OCPs in the Danshui River Basin. OCPs and PAHs emitted from agricultural or other human activities could enter the groundwater and then be transported to the surface/river water in the karst area. The adsorption of OCPs and PAHs by particles and the sedimentation of particles could be the primary processes to intercept these pollutants in the water of the karstic river system.

Sources of PM2.5-Associated PAHs and n-alkanes in Changzhou China

Polycyclic aromatic hydrocarbons (PAHs) and n-alkanes are important specific organic constituents in fine particulate matter (PM2.5). Seventy-five PM2.5 samples were collected in Spring Changzhou, to investigate the concentrations and sources of n-alkanes (C9–C40) and PAHs. The average concentrations of total PAHs (∑PAHs) and n-alkanes (∑n-alkanes) were 4.37 ± 4.95 ng/m3 and 252.37 ± 184.02 ng/m3, ranging from 0.43 to 22.22 ng/m3 and 57.37 to 972.17 ng/m3, respectively. The average concentrations of ∑n-alkanes and ∑PAHs were higher in severely polluted days (PM2.5 ≥ 150 μg/m3) in comparison to other days. Up to 85% of PAHs were four- and five-ring compounds, and the middle-chain-length n-alkanes (C25–C35) were the most abundant species (80.9%). The molecular distribution of n-alkanes was characterized by odd-number carbon predominance (carbon preference index, CPI &gt; 1), with a maximum centered at C27, C29, and C31 revealing a significant role of biogenic sources. Principal component analysis suggested that the biogenic sources that contributed the most to n-alkanes and PAHs were from coal combustion (46.3%), followed by biomass burning (16.0%), and vehicular exhaust (10.3%). The variation in the concentration of n-alkanes and PAHs from different air mass transports was not agreement with the change in PM2.5 mass, indicating that regional transport had important impacts on the characterization of PM2.5. The results of our study can provide useful information for evaluating the influence of anthropogenic and biogenic activities on organic matters (n-alkanes and PAHs).

Characterization and risk assessment of polycyclic aromatic hydrocarbon emissions by coal fire in northern China.

Coal spontaneous combustion is known to emit a variety of organic carcinogenic pollutants, polycyclic aromatic hydrocarbons (PAHs) are the most prominent. The Wuda coalfield is a coal fire-prone region in northern China. Coal fire sponges (CFS), a sponge-like contaminated soil protrusion, occur widely in the Suhaitu mining area. PAHs concentrations in CFS were measured via GC × GC-TOFMS. The average total PAHs concentration in the central annulus (A) was 17,416μgkg-1 and ranged from 292 to 218,251μgkg-1. Moreover, the study exhibited a heavily contaminated level (1000μgkg-1). Low molecular weight PAHs were dominant, accounting for more than 50% of the total PAHs. Among them, naphthalene (Nap) and phenanthrene (Phe) were the most prominent, and the correlation between Phe and Nap + Phe was highly significant (R2 > 0.9). Our findings indicated that Nap and Phe contents may constitute a novel indicator to identify coal fire emission sources. Cancer risk calculations indicated that all annulus is already at a potential risk stage (10-6-10-4) for child or adults. CFS is not only a coal fire-associated PAH sink but also an atmospheric PAH emission source and, therefore, warrants the attention of local authorities.

Atmospheric particle-bound polycyclic aromatic compounds over two distinct sites in Pakistan: Characteristics, sources and health risk assessment

Much attention is drawn to polycyclic aromatic hydrocarbons (PAHs) as an air pollutant due to their toxic, mutagenic and carcinogenic properties. Therefore, to understand the levels, seasonality, sources and potential health risk of PAHs in two distinct geographical locations at Karachi and Mardan in Pakistan, total suspended particle (TSP) samples were collected for over one year period. The average total PAH concentrations were 31.5 ± 24.4 and 199 ± 229 ng/m3 in Karachi and Mardan, respectively. The significantly lower concentration in Karachi was attributed to diffusion and dilution of the PAHs by the influence of clean air mass from the Arabian sea and high temperature, enhancing the volatilization of the particle phase PAHs to the gas phase. Conversely, the higher concentration (~6 times) in Mardan was due to large influence from local and regional emission sources. A clear seasonality was observed at both the sites, with the higher values in winter and post-monsoon due to higher emissions and less scavenging, and lower values during monsoon season due to the dilution effect. Diagnostic ratios and principal component analysis indicated that PAHs in both sites originated from traffic and mixed combustion sources (fossil fuels and biomass). The average total BaP equivalent concentrations (BaPeq) in Karachi and Mardan were 3.26 and 34 ng/m3, respectively, which were much higher than the WHO guideline of 1 ng/m3. The average estimates of incremental lifetime cancer risk from exposure to airborne BaPeq via inhalation indicated a risk to human health from atmospheric PAHs at both sites.

The Health Risks of Airborne Polycyclic Aromatic Hydrocarbons (PAHs): Upper North Thailand.

Every year, Northern Thailand faces haze pollution during the haze episode. The particulate matter (PM), including fine fraction (PM2.5), a coarse fraction (PM2.5–10), and 16 polycyclic aromatic hydrocarbons (PAHs), was measured in six provinces in upper north Thailand during the haze and non‐haze episodes in 2018. Eighty‐three percent of the PM2.5 measurements (21.8–194.0 µg/m3) during the haze episode exceeded the national ambient air quality standard in Thailand. All 16 PAHs were detected in the study area in both periods. The average concentration of total PAHs (particle‐bound and gas‐phase) during the haze episode was 134.7 ± 80.4 ng/m3, which was about 26 times higher than those in the non‐haze (5.1 ± 9.7 µg/m3). Naphthalene and acenaphthene were the dominant PAHs in the gas phase; whereas, indeno[123‐cd] pyrene, benzo[a]pyrene, and Benzo[ghi]Perylene were dominant in the particle‐bound phase. The estimated inhalation excess cancer risk from PAHs exposure was 9.3 × 10−4 and 2.5 × 10−5 in the haze episode and non‐haze, respectively. Diagnostic ratios and principal component analysis revealed that PAHs were derived from mixed sources of vehicle emission and solid combustion in the haze episode and vehicle emission in the non‐haze period. High pollution levels of PM and large cancer risk attributable to the exposure of PAHs in the haze episode suggest urgent countermeasures to reduce the source emission, especially from the solid combustion in the area.

Evaluation of Polycyclic Aromatic Hydrocarbons (PAHs) in Bamboo Shoots from Soil.

The toxicity, carcinogenicity and persistence of polycyclic aromatic hydrocarbons (PAHs) pose a great threat to the ecological system and human health. The contamination levels, translocation and source analysis of 16 PAHs in bamboo shoot and its planted soil were investigated. The average concentrations of total PAHs were 18.80 ± 1.90 µg/kg and 123.98 ± 113.36 µg/kg in bamboo shoots and soils, respectively. The most abundant PAH was Phenanthrene (PHE), with the detected average concentrations of 5.85 µg/kg in bamboo shoots and 19.28 µg/kg in soils. The highest detected types of PAHs were 3 rings and 4 rings, with the proportions of 80.69% (bamboo shoots) and 35.23% (soils). The transfer factors of PAHs were ranged from 0.011 to 0.895, in which PAHs with 3 rings showed the strongest transfer ability. The combustion of biomass and petroleum might be the main source of PAHs in the planted soils of bamboo shoots.

Particulate bound polycyclic aromatic hydrocarbons over Dhauladhar region of the north-western Himalayas

A systematic yearlong study was carried out in Dhauladhar region of the North-Western Himalayas to investigate dynamics in the composition and concentration of particulate bound polycyclic aromatic hydrocarbons (PAHs) and their source(s) activity. PM10 samples were collected for 24 h, once every week during January 2015–January 2016, at an urban mid-altitude site (Dharamshala) and a rural low-altitude site (Pohara). PAHs were identified and quantified using high performance liquid chromatography coupled with UV-detector. Seasonal average concentration of total PAHs followed a pattern: Summer > Winter > Autumn > Spring in the region. Seasonal average values of molecular diagnostic ratios indicated significant contribution from non-traffic (biomass burning and coal combustion) sources also during winter and spring season, whereas, traffic emissions (gasoline and diesel) were the dominant source at both the locations throughout the year in the region. The Principal Component Analysis deciphered a) emissions from gasoline driven vehicles b) diesel engine exhaust emissions c) biomass/wood burning source d) coal combustion and e) waste incineration and burning of oil/tar as major sources of PAHs in the region. Annual mean values of total Benzo(a)Pyrene Equivalent were much higher than 1 ng.m-3 over both the locations indicating higher lung cancer risk to the people living in this part of the Himalayas.

Polycyclic aromatic hydrocarbons and their nitro-derivatives in urban road dust across China: Spatial variation, source apportionment, and health risk

As an essential carrier of hazardous substances, fugitive road dust has become a severe issue in China. In this study, 212 road dust samples from 53 cities in China were collected to comprehensively investigate the spatial variations, potential sources, and cancer risk of 16 polycyclic aromatic hydrocarbons (PAHs) and 16 nitro-PAHs. The total PAHs concentrations ranged from 0.07 to 345 μg/g dry weight, which is at a moderate level compared to other regions in the world. The mean concentration of Σ16nitro-PAHs was 111 ± 115 ng/g, which is 2–3 orders of magnitude lower than that of Σ16PAHs. A clear geographical trend of dust PAHs and nitro-PAHs was observed in the northeast, north, and east coastal regions of China at a higher level. Moreover, a significant correlation between latitude and PAHs/nitro-PAHs revealed the influences of outdoor temperature and coal combustion for heating in the different regions on the emission and reaction of PAHs and nitro-PAHs. The secondary formation of most nitro-PAHs increases with a decrease in latitude indicated that solar radiation and temperature are important factors on secondary formation of nitro-PAHs. The average concentration of total PAHs and their derivatives in trunk road samples were statistically higher than those in other road samples (p < 0.05), indicating the influence of traffic load on target compound concentration. Generally, the primary sources of PAHs in the road dust samples were coal combustion (23.9%), vehicles (57.1%), and wood/biomass combustion (19.0%). For nitro-PAHs, the main sources were secondary formation (30.9%), biomass/coal combustion (28.4%), and vehicles (44.9%). Furthermore, a moderate potential carcinogenic risk due to PAHs and nitro-PAHs in the dust samples was found in China.

Determination of polycyclic aromatic hydrocarbons (PAHs) in drinking water of Samsun and it's surrounding areas, Turkey.

Polycyclic aromatic hydrocarbons (PAH) are considered to be one of the major contaminants of drinking water and natural water bodies. Some of the well documented polycyclic aromatic hydrocarbons that are water pollutants and were considered for analysis in this study included benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), benzo[g,h,i]perylene (BgP), and indeno[1,2,3-c,d]pyrene (InD). This study aimed at determining the levels of concentrations of basically five polycyclic aromatic hydrocarbons in 57 drinking water bodies located around Samsun, Ordu, Giresun, Çorum, Amasya, Kastamonu and Sinop provinces. In this study, the Environmental Protection Agency (EPA) method 550.1 for the determination of polycyclic aromatic hydrocarbons in drinking by Liquid-Solid Extraction (LSE) and High Performance Liquid Chromatography (HPLC) with Coupled Ultraviolet (CD) and Fluorescence Detection (FD) was used. Sampling procedures were done according to the validated method specified by the Turkish Ministry of Enivironment and Forestry. Prior to the determination of concentrations by HPLC, PAHs contained in the samples were separated from the solid phase by Solid-Phase Extraction (SPE). All data analyses were conducted using SPSS and Excel. Obtained results from the investigation revealed that the average total PAH and benzo[a]pyrene (BaP) concentration levels in drinking water samples taken from the central districts of Samsun were 2.73 ± 1.51 and 0.35 ± 0.24ng/L respectively. In drinking water samples taken from Ordu, Giresun, Çorum, Amasya, Kastamonu and Sinop, the average total PAH concentrations were found to be 5.85 ± 3.82ng/L, 3.79 ± 1.27ng/L, 1.08 ± 0.62ng/L, 2.42 ± 1.04ng/L; 1.92 ± 0.35ng/L and 4.07 ± 2.33ng/L respectively. The average (BaP) concentrations for the same named locations were determined as 0.97 ± 0.75ng/L; 0.55 ± 0.29ng/L; 0.11 ± 0.08ng/L; 0.35 ± 0.10ng/L; 0.14 ± 0.04ng/L; 0.39 ± 0.23ng/L, respectively. It is therefore evident that the values ​​of PAH and BaP in drinking water were below the limits of 100 and 10ng/L ​​specified in the Regulation on Water Intended for Human Consumption. These values are below the set limits proposed by Turkish legislation and WHO. All the results for drinking water, usable water and natural spring water were below the values ​​specified in the Regulation on Water Intended for Human Consumption and WHO. The PAH content of the studied river waters as well were below the limits proposed by Turkish legislation and WHO.

Source identification and health risk assessment of atmospheric PM2.5-bound polycyclic aromatic hydrocarbons in Jamshedpur, India

Occurrence and persistence of Polycyclic Aromatic Hydrocarbons (PAHs) in the environment pose a serious human health risk. In this study, the sources and characteristics of 16 Polycyclic Aromatic Hydrocarbons (PAHs) associated with the emission of particulate matter (PM) from semi-urban, urban, and rural sections of Jamshedpur City, India was investigated using advanced gas chromatography. The results of sampling conducted during winter and summer seasons suggest that the total PAHs average concentration level were higher in the winter season than the concentration level in the summer season. During the winter season, the average concentration of total PAHs from semi-urban, urban, and rural sites were found to be 47.73 ± 10.65, 37 ± 9.56, and 109.06 ± 18.21 ng/m3 respectively while in summer season, the concentration was observed to be 39.61 ± 6.87, 81.14 ± 13.30 and 36.33 ± 9.97 ng/m3 over semi-urban, urban and rural site respectively. Of all the PAHs, Phenanthrene (Phe) was among the most abundant PAH in both winter and summer seasons over the entire study site. Diagnostic Ratio Analysis (DRA) & Principal component analysis (PCA) demonstrated that major emission sources of PAHs were; the vehicles, petrogenic, and biomass and coal combustion sources over semi-urban, urban, and rural site. BaP & DBahA were used as the surrogate compounds in assessing PAHs health risk. The Excess Lifetime Cancer Risk (ELCR) value over the semi-urban, urban, and rural site was calculated as 10.25 × 10−6, 23.09 × 10−6 and 18.86 × 10−6 respectively.

Distribution of 16 Polycyclic Aromatic Hydrocarbons in Dianchi Lake Surface Sediments After the Integrated Water Environment Control Project

The external pollution of Dianchi Lake has been effectively controlled with the implementation of the integrated water environment control project. However, further attention should be paid to endogenous pollutants, such as surface sediments. To investigate the distribution of 16 polycyclic aromatic hydrocarbons (PAHs) in surface sediments of Dianchi Lake, PAH concentrations in 19 surface sediment samples (collected in December 2016) were quantitatively measured by gas chromatography-mass spectrometry (GC-MS). The spatial and temporal distribution, sources, and ecological risks were also analyzed. The concentration of total PAHs (TPAHs) in the Dianchi Lake surface sediments varied in the range of 92.31-1546.78 ng·g-1 with an average of 496.30 ng·g-1. The average concentration of TPAHs in the surface sediments from Caohai (932.37 ng·g-1) was much greater than that from Waihai (380.02 ng·g-1). With the implement of the integrated water environment control project, the concentration of TPAHs in the surface sediments from Dianchi Lake was significantly lower than those detected in 2012, and was already relatively low level among other key waterbodies in China. The PAH with the highest concentration was fluoranthene (80.65 ng·g-1) and the substance with the highest toxic equivalent quantity (TEQ) was dibenz[a, h] anthracene (42.97 ng·g-1). The PAHs were mainly composed of 4 ring and 5-6 ring compounds (with the concentration ratio of 40.38% and 40.22%, respectively), which indicated that the proportions of middle-ring and high-ring compounds were generally consistent. The results of the molecular diagnostic ratio analysis showed that the primary source of PAHs in Dianchi Lake surface sediments are biomass and coal combustion. Based on the potential ecological risk marker comparison method, the entire lake was classified as having a low ecological risk, while the ecological risk of Caohai was relatively higher, which should be concerned further. The results provide initial data and act as an important reference for the conservation and improvement of water quality in Dianchi Lake.