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Verma PK, Devaprasad M, Dave J, Meena R, Bhowmik H, Tripathi SN, Rastogi N. Summertime oxidative potential of atmospheric PM 2.5 over New Delhi: Effect of aerosol ageing. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 920:170984. [PMID: 38365025 DOI: 10.1016/j.scitotenv.2024.170984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 02/12/2024] [Accepted: 02/13/2024] [Indexed: 02/18/2024]
Abstract
Exposure to elevated particulate matter (PM) concentrations in ambient air has become a major health concern over urban areas worldwide. Reactive oxygen species (ROS) generation due to ambient PM (termed as their oxidative potential, OP) is shown to play a major role in PM-induced health effects. In the present study, the OP of the ambient PM2.5 samples, collected during summer 2019 from New Delhi, were measured using the dithiothreitol (DTT) assay. Average volume-normalized OP (OPV) was 2.9 ± 1.1 nmol DTT min-1 m-3, and mass-normalized OP (OPm) was 61 ± 29 pmol DTT min-1 μg-1. The regression statistics of OPv vs chemical species show the maximum slope of OPV with the elemental carbon (EC, r2 = 0.72) followed by water-soluble organic carbon (WSOC, r2 = 0.72), and organic carbon (OC, r2 = 0.64). A strong positive correlation between OPm and secondary inorganic aerosols (SIA, such as NH4+ and NO3- mass fractions) was also observed, indicating that the sources emitting NO2 and NH3, precursors of NO3- and NH4+, also emit DTT-active species. Interestingly, the slope value of OPv vs OC for aged aerosols (OM/OC > 1.7, f44 > 0.12 and f43 < 0.04) was 1.7 times higher than relatively fresh organic aerosols (OA, OM/OC < 1.7, f44 < 0.12, f43 > 0.04). An increase in OPv and OPoc with f44 indicates the formation of more DTT active species with the ageing of OA. A linear increase in OPoc with increasing Nitrogen/Carbon (N/C) ratio suggests that nitrogenous OA have higher OP.
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Affiliation(s)
- P K Verma
- Geosciences Division, Physical Research Laboratory, Ahmedabad, Gujarat 380009, India.
| | - M Devaprasad
- Geosciences Division, Physical Research Laboratory, Ahmedabad, Gujarat 380009, India; Indian Institute of Technology, Gandhinagar, Gujarat 382355, India
| | - J Dave
- Geosciences Division, Physical Research Laboratory, Ahmedabad, Gujarat 380009, India
| | - R Meena
- Geosciences Division, Physical Research Laboratory, Ahmedabad, Gujarat 380009, India
| | - H Bhowmik
- Department of Civil Engineering, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India
| | - S N Tripathi
- Department of Civil Engineering, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India
| | - N Rastogi
- Geosciences Division, Physical Research Laboratory, Ahmedabad, Gujarat 380009, India.
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Tala W, Kraisitnitikul P, Chantara S. Impact of Atmospheric Conditions and Source Identification of Gaseous Polycyclic Aromatic Hydrocarbons (PAHs) during a Smoke Haze Period in Upper Southeast Asia. TOXICS 2023; 11:990. [PMID: 38133391 PMCID: PMC10748124 DOI: 10.3390/toxics11120990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 11/30/2023] [Accepted: 12/01/2023] [Indexed: 12/23/2023]
Abstract
Gaseous polycyclic aromatic hydrocarbons were measured in northern Thailand. No previous studies have provided data on gaseous PAHs until now, so this study determined the gaseous PAHs during two sampling periods for comparison, and then they were used to assess the correlation with meteorological conditions, other pollutants, and their sources. The total concentrations of 8-PAHs (i.e., NAP, ACY, ACE, FLU, PHE, ANT, FLA, and PYR) were 125 ± 22 ng m-3 and 111 ± 21 ng m-3, with NAP being the most pronounced at 67 ± 18 ng m-3 and 56 ± 17 ng m-3, for morning and afternoon, respectively. High temperatures increase the concentrations of four-ring PAHs, whereas humidity and pressure increase the concentrations of two- and three-ring PAHs. Moreover, gaseous PAHs were estimated to contain more toxic derivatives such as nitro-PAH, which ranged from 0.02 ng m-3 (8-Nitrofluoranthene) to 10.46 ng m-3 (1-Nitronaphthalene). Therefore, they could be one of the causes of local people's health problems that have not been reported previously. Strong correlations of gaseous PAHs with ozone indicated that photochemical oxidation influenced four-ring PAHs. According to the Pearson correlation, diagnostic ratios, and principal component analysis, mixed sources including coal combustion, biomass burning, and vehicle emissions were the main sources of these pollutants.
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Affiliation(s)
- Wittaya Tala
- Environmental Science Research Center (ESRC), Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; (P.K.); (S.C.)
- Office of Research Administration, Chiang Mai University, Chiang Mai 50200, Thailand
- Environmental Chemistry Research Laboratory (ECRL), Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Pavidarin Kraisitnitikul
- Environmental Science Research Center (ESRC), Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; (P.K.); (S.C.)
- Office of Research Administration, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Somporn Chantara
- Environmental Science Research Center (ESRC), Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; (P.K.); (S.C.)
- Environmental Chemistry Research Laboratory (ECRL), Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
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Drventić I, Glumac M, Carev I, Kroflič A. Seasonality of Polyaromatic Hydrocarbons (PAHs) and Their Derivatives in PM 2.5 from Ljubljana, Combustion Aerosol Source Apportionment, and Cytotoxicity of Selected Nitrated Polyaromatic Hydrocarbons (NPAHs). TOXICS 2023; 11:518. [PMID: 37368618 DOI: 10.3390/toxics11060518] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/29/2023] [Accepted: 06/01/2023] [Indexed: 06/29/2023]
Abstract
Airborne particulate matter (PM) is a vector of many toxic pollutants, including polyaromatic hydrocarbons (PAHs) and their derivatives. Especially harmful is the fine fraction (PM2.5), which penetrates deep into the lungs during inhalation and causes various diseases. Amongst PM2.5 components with toxic potential are nitrated PAHs (NPAHs), knowledge of which is still rudimentary. Three of the measured NPAHs (1-nitropyrene (1-nP), 9-nitroanthracene (9-nA), and 6-nitrochrysene (6-nC)) were detected in ambient PM2.5 from Ljubljana, Slovenia, along with thirteen non-nitrated PAHs. The highest concentrations of pollutants, which are closely linked with incomplete combustion, were observed in the cold part of the year, whereas the concentrations of NPAHs were roughly an order of magnitude lower than those of PAHs throughout the year. Further on, we have evaluated the toxicity of four NPAHs, including 6-nitrobenzo[a]pyrene (6-nBaP), to the human kidney cell line, HEK293T. The most potent was 1-nP (IC50 = 28.7 µM), followed by the other three NPAHs, whose IC50 was above 400 or 800 µM. According to our cytotoxicity assessment, atmospheric 1-nP is the most harmful NPAH among the investigated ones. Despite low airborne concentrations of NPAHs in ambient air, they are generally considered harmful to human health. Therefore, systematic toxicological assessment of NPAHs at different trophic levels, starting with cytotoxicity testing, is necessary in order to accurately evaluate their threat and adopt appropriate abatement strategies.
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Affiliation(s)
- Ivana Drventić
- Department of Analytical Chemistry, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, 1000 Ljubljana, Slovenia
| | - Mateo Glumac
- Laboratory for Cancer Research, School of Medicine, University of Split, Šoltanska 2, 21000 Split, Croatia
| | - Ivana Carev
- NAOS Institute of Life Science, 355 rue Pierre-Simon Laplace, 13290 Aix-en-Provence, France
- Mediterranean Institute for Life Science, Meštrovićevo šetalište 45, 21000 Split, Croatia
- Faculty of Science, University of Split, Ruđera Boškovića 33, 21000 Split, Croatia
| | - Ana Kroflič
- Department of Catalysis and Chemical Reaction Engineering, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
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Compositional and seasonal differences of gas and particle phase polycyclic aromatic hydrocarbons (PAHs) over the southern Baltic Sea coast. Sci Rep 2022; 12:21005. [PMID: 36471002 PMCID: PMC9723112 DOI: 10.1038/s41598-022-25666-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022] Open
Abstract
In this study, 16 USEPA-prioritized PAHs in gas- and particle-phase (PAHg+p), associated chemical and meteorological parameters, and backward trajectory simulations were explored in a coastal city in Poland, between April 2019 and May 2020. This study reports several important aspects of PAHg+p, i.e. variation, composition, distribution profiles, impact of weather conditions, and correlation analysis between target PAH compounds and influencing inorganic gaseous pollutants. Specifically, higher and more variable concentrations of total PAHg+p (mean ± SD, ng m-3) were observed during winter (36.38 ± 24.19) compared to autumn (22.3 ± 17.44), summer (21.52 ± 13.30) and spring (19.90 ± 13.13). A distribution profile of parent PAHg+p was as follows: 3-ring > 4-ring > 2-ring > 5-ring > 6-ring, although their relative contribution to the total PAHs showed statistically significant differences between seasons (p < 0.05). Precipitation-driven loss of ΣPAHg+p was lower in the warm period than in the cold one, reflecting higher PAH concentrations in winter. A seasonal model-based analysis of incremental lifetime cancer risk showed a higher potential cancer risk for children than those for adult females and males. The adverse health impacts associated with PAH exposure via inhalation route indicate the need for implementation of pollution-control policies in this region.
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Han F, Kota SH, Sharma S, Zhang J, Ying Q, Zhang H. Modeling polycyclic aromatic hydrocarbons in India: Seasonal variations, sources and associated health risks. ENVIRONMENTAL RESEARCH 2022; 212:113466. [PMID: 35618010 DOI: 10.1016/j.envres.2022.113466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 05/02/2022] [Accepted: 05/09/2022] [Indexed: 06/15/2023]
Abstract
Atmospheric polycyclic aromatic hydrocarbons (PAHs) are in high levels in developing countries like India. However, limited measurements are inadequate for better understanding of their ambient levels and health effects. This study predicted PAHs concentrations in atmosphere and estimated their sources and health risks in India in four representative months of winter, pre-monsoon, monsoon and post-monsoon in 2015 using an updated version of the Community Multiscale Air Quality model (CMAQ). Predicted PAHs were in agreement with observations from literature. Surface 16-PAHs were highest in winter, with a peak value of 2.5 μg/m3 and population-weighted average of 0.5 μg/m3 in northern and eastern India, where biomass burning and coal combustion were chief contributors. Pre-monsoon and monsoon had lower concentrations ∼0.2 μg/m3. The incremental lifetime cancer risk (ILCR) was greater than 4E-4 in many industrial and urban areas. Exposure to PAHs resulted in 7431 excess lifetime cancer cases. Coal combustion and biomass burning were major contributors to ILCR, followed by gas and oil activities. Much higher health risks were observed in urban than in rural areas. India showed much higher levels of total PAHs and cPAHs than the U.S but moderately less than China.
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Affiliation(s)
- Fenglin Han
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200348, China; Department of Civil and Environmental Engineering, Louisiana State University, Baton Rouge, LA, 70803, United States
| | - Sri Harsha Kota
- Department of Civil Engineering, Indian Institute of Technology Delhi, 110016, India; Arun Duggal Centre of Excellence for Research in Climate Change and Air Pollution (CERCA), IIT Delhi, New Delhi, 110016, India.
| | - Shubham Sharma
- Department of Civil Engineering, Indian Institute of Technology Delhi, 110016, India
| | - Jie Zhang
- Zachary Department of Civil Engineering, Texas A&M University, College Station, TX, 77845, United States
| | - Qi Ying
- Zachary Department of Civil Engineering, Texas A&M University, College Station, TX, 77845, United States
| | - Hongliang Zhang
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200348, China; Department of Civil and Environmental Engineering, Louisiana State University, Baton Rouge, LA, 70803, United States.
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Verma PK, Sah D, Satish R, Rastogi N, Kumari KM, Lakhani A. Atmospheric chemistry and cancer risk assessment of Polycyclic Aromatic Hydrocarbons (PAHs) and Nitro-PAHs over a semi-arid site in the Indo-Gangetic plain. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 317:115456. [PMID: 35751260 DOI: 10.1016/j.jenvman.2022.115456] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 02/04/2022] [Accepted: 05/28/2022] [Indexed: 06/15/2023]
Abstract
Polycyclic Aromatic Hydrocarbons (PAHs) and Nitro-PAHs were collected over a year at a traffic dominated site in Agra, to determine the dominant partitioning mechanism. During the entire sampling period, total PAHs and Nitro-PAHs were 3465 ± 3802 and 26.1 ± 25.9 ng m-3 respectively. The gas-particle partitioning behavior of PAHs was studied by applying the Pankow model, Absorption model, and Dual model. Amongst all the partitioning models, the Dual model fits well and indicates that the partitioning of PAHs at the traffic site in Agra depends on both the physical adsorption of PAHs on the Total Suspended Particulate (TSP) surface and absorption of PAHs into the organic layer present on the TSP surface. Pankow model indicates that PAHs are emitted from the source close to the sampling point and due to this PAHs do not get enough time to get partitioned in between both the phases. Incremental lifetime Cancer Risk (ILCR) shows that adults and children are more prone to cancer risk in comparison to infants for both PAHs and Nitro-PAHs. Cancer risk by inhalation was minimum in comparison to both ingestion and dermal exposure. Nitro-PAHs in the particulate phase were high enough to exceed the minimum permissible limit (10-6) of causing cancer by ingestion and dermal exposure.
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Affiliation(s)
- Puneet Kumar Verma
- Department of Chemistry, Dayalbagh Educational Institute, Agra, 282005, India
| | - Dinesh Sah
- Department of Chemistry, Dayalbagh Educational Institute, Agra, 282005, India
| | - Rangu Satish
- Geosciences Division, Physical Research Laboratory, Navrangpura, Ahmedabad, 380009, India
| | - Neeraj Rastogi
- Geosciences Division, Physical Research Laboratory, Navrangpura, Ahmedabad, 380009, India
| | - K Maharaj Kumari
- Department of Chemistry, Dayalbagh Educational Institute, Agra, 282005, India
| | - Anita Lakhani
- Department of Chemistry, Dayalbagh Educational Institute, Agra, 282005, India.
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Dat ND, Thuan NT, Hoang NTT, Tran HN, Hien TT, Tran KT, Chang MB. Characteristics of polycyclic aromatic hydrocarbons in ambient air of a tropical mega-area, Ho Chi Minh City, Vietnam: concentration, distribution, gas/particle partitioning, potential sources and cancer risk assessment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:44054-44066. [PMID: 35122647 DOI: 10.1007/s11356-022-18859-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 01/21/2022] [Indexed: 06/14/2023]
Abstract
This is the first investigation on overall characteristics of 25 polycyclic aromatic hydrocarbons (PAHs) (15 PAHs regulated by US-EPA (excluding naphthalene) and 16 PAHs recommended by the European Union) in ambient air of Ho Chi Minh City, Vietnam. Their levels, congener profiles, gas/particle partitioning, potential sources of atmospheric PAHs (gas and particulate phases), and lung cancer risks in the dry and rainy seasons were examined. The ∑25 PAH concentration in the dry and rainy seasons ranged from 8.79 to 33.2 ng m-3 and 26.0 to 60.0 ng m-3, respectively. Phenanthrene and Indeno[123-cd]pyrene were major contributors to gaseous and particulate PAHs, respectively, while benzo[c]fluorene was dominant component of the total BaP-TEQ. The ∑16 EU-PAH concentration contributed to 13 ± 2.7% of the total ∑ 25 PAH concentration; however, they composed over 99% of the total ∑ 25 PAH toxic concentration. Adsorption mainly governed the phase partitioning of PAHs because the slope of correlation between logKp and logP0L was steeper than - 1. Vehicular emission was the primary source of PAHs in two seasons; however, PAHs in the dry season were also originated from biomass burning. Assessment of lung cancer risk showed that children possibly exposed to potential lung cancer risk via inhalation.
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Affiliation(s)
- Nguyen Duy Dat
- Faculty of Chemical and Food Technology, Ho Chi Minh City University of Technology and Education, Ho Chi Minh City, Vietnam, 700000
| | - Ngo Thi Thuan
- Department of Environmental Engineering, International University, Linh TrungWard, Quarter 6Thu Duc City, Ho Chi Minh City, Vietnam.
- Vietnam National University, Linh Trung Ward, Thu Duc District, Ho Chi Minh City, Vietnam.
| | - Nhung Thi-Tuyet Hoang
- Faculty of Chemical and Food Technology, Ho Chi Minh City University of Technology and Education, Ho Chi Minh City, Vietnam, 700000
| | - Hiep Ngoc Tran
- Faculty of Chemical and Food Technology, Ho Chi Minh City University of Technology and Education, Ho Chi Minh City, Vietnam, 700000
| | - To Thi Hien
- Vietnam National University, Linh Trung Ward, Thu Duc District, Ho Chi Minh City, Vietnam
- Faculty of Environmental Science, University of Science, Ward 4, District 5, Ho Chi Minh City, Vietnam
| | - Khoi Tien Tran
- Department of Environmental Engineering, International University, Linh TrungWard, Quarter 6Thu Duc City, Ho Chi Minh City, Vietnam
- Vietnam National University, Linh Trung Ward, Thu Duc District, Ho Chi Minh City, Vietnam
| | - Moo Been Chang
- Graduate Institute of Environmental Engineering, National Central University (NCU), Zhongli, Taiwan, 32001.
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Wu M, Luo J, Huang T, Lian L, Chen T, Song S, Wang Z, Ma S, Xie C, Zhao Y, Mao X, Gao H, Ma J. Effects of African BaP emission from wildfire biomass burning on regional and global environment and human health. ENVIRONMENT INTERNATIONAL 2022; 162:107162. [PMID: 35247686 DOI: 10.1016/j.envint.2022.107162] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 02/17/2022] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
The vegetation burning caused by wildfires can release significant quantities of aerosols and toxic chemicals into the atmosphere and result in health risk. Among these emitted pollutants, Benzo(a)pyrene (BaP), the most toxic congener of 16 parent PAHs (polycyclic aromatic hydrocarbons), has received widespread concerns because of its carcinogenicity to human health. Efforts have been made to investigate the environmental and health consequences of wildfire-induced BaP emissions in Africa. Still, uncertainties remain due to knowledge and data gaps in wildfire incidences and biomass burning emissions. Based on a newly-developed BaP emission inventory, the present study assesses quantitatively the BaP environment cycling in Africa and its effects on other continents from 2001 to 2014. The new inventory reveals the increasing contribution of BaP emission from African wildfires to the global total primarily from anthropogenic sources, accounting for 48% since the 2000 s. We identify significantly higher BaP emissions and concentrations across sub-Saharan Africa, where the annual averaged BaP concentrations were as high as 5-8 ng/m3. The modeled BaP concentrations were implemented to estimate the lifetime cancer risk (LCR) from the inhalation exposure to BaP concentrations. The results reveal that the LCR values in many African countries exceeded the acceptable risk level at 1 × 10-6, some of which suffer from very high exposure risk with the LCR>1 × 10-4. We show that the African BaP emission from wildfires contributed, to some extent, BaP contamination to Europe as well as other regions, depending on source proximity and atmospheric pathways under favorable atmospheric circulation patterns.
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Affiliation(s)
- Min Wu
- Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
| | - Jinmu Luo
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Tao Huang
- Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
| | - Lulu Lian
- Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
| | - Tianlei Chen
- Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
| | - Shijie Song
- Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
| | - Zhanxiang Wang
- Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
| | - Shuxin Ma
- Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
| | - Chaoran Xie
- Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
| | - Yuan Zhao
- Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
| | - Xiaoxuan Mao
- Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
| | - Hong Gao
- Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
| | - Jianmin Ma
- Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China; Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
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Sharma S, Loach N, Gupta S, Mohan L. Evaluation of larval toxicity, mode of action and chemical composition of citrus essential oils against Anopheles stephensi and Culex quinquefasciatus. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2022. [DOI: 10.1016/j.bcab.2022.102284] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Temporal Distribution and Gas/Particle Partitioning of Polycyclic Aromatic Hydrocarbons (PAHs) in the Atmosphere of Strasbourg, France. ATMOSPHERE 2021. [DOI: 10.3390/atmos12030337] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Gas and particulate phase ambient air concentrations of polycyclic aromatic hydrocarbons (Ʃ16PAHs) were determined in Strasbourg, a large city located in the Alsace region of northeastern France, from May 2018 to March 2020, to study the evolution of their temporal variations and their potential origins. The analysis of PAHs was performed using a global analytical method permitting the quantification of pesticides, PAHs, and polychlorobiphenyls (PCBs). Filters and Carbon doped silicon carbide NMC@SiC foams were extracted by accelerated solvent extraction (ASE) followed by a solid-phase extraction (SPE). Afterwards, extracts were analyzed using gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). Prior to analysis, a pre-concentration step based on solid-phase microextraction (SPME) was used with a polydimethylsiloxane (PDMS) 100 µm fiber. The average total (gas plus particulate) concentration of Ʃ16PAHs varied from 0.51 to 117.31 ng m−3 with a mean of 16.87 ng m−3, with higher concentrations in the cold season of more than 2.5-fold and 6-fold that in the warm season for the gas and particulate phases, respectively. Moreover, low molecular weight (LMW) (2-ring and 3-ring) and medium molecular weight (MMW) (4-ring) PAHs contribute dominantly to the gas phase, while the particulate phase is associated with MMW (4-ring) and high molecular weight (HMW) (5-ring and 6-ring) PAHs. Gas/particle partitioning coefficient (log Kp) was calculated, and values varied between −4.13 and −1.49. It can be seen that the log Kp increased with the molecular weight of the PAHs and that the log Kp is different between cold and warm seasons for HMW PAHs but not for LMW PAHs. Diagnostic ratios of PAHs, which were employed to estimate the primary source of PAHs in Strasbourg, indicate that fuel combustion and biomass/coal burning are the possible origins of PAHs in Strasbourg’s atmosphere.
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Verma PK, Sah D, Dubey J, Kumari KM, Lakhani A. Mutagenic and Cancer Risk Estimation of Particulate Bound Polycyclic Aromatic Hydrocarbons from the Emission of Different Biomass Fuels. Chem Res Toxicol 2021; 34:743-753. [PMID: 33591737 DOI: 10.1021/acs.chemrestox.0c00378] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Smoke samples from combustion of different biomass fuels were analyzed for the particulate bound Polycyclic Aromatic Hydrocarbons (PAHs) due to their carcinogenic and mutagenic nature. Out of 16 priority PAHs, 11 PAHs were detected in the emission of fuels, while the remaining 5 PAHs (chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, indeno[1,2,3-cd]pyrene, and benzo[g,h,i]perylene) were below the detection limit. The highest emission factor for the sum of all the PAHs was found for coal (353.08 mg kg-1), charcoal (27.28 mg kg-1), and the various wood types. Emission rates of total PAHs ranged from 0.37 to 5.15 mg h-1 with the highest value for bituminous coal (5.15 mg h-1) and lowest for Polyalthia longifolia (0.37 mg h-1). A cancer risk assessment was done for infants, children, and adults using the incremental lifetime cancer risk (ILCR) model via ingestion, inhalation, and dermal contact pathway. The ILCR values ranged from 10-11 to 10-6, and a higher cancer risk was observed for children and adults in comparison to infants. PAH concentrations emitted from biomass emissions shows a direct correlation with mutagenesis to humans, indicating a higher potential for the frameshift mutation as compared to base-pair mutation for dung, bituminous coal, charcoal, Dalbergia sissoo, Psidium guajava, Ziziphus mauritana, Polyalthia longifolia, and Ailanthus trithesa.
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Affiliation(s)
- Puneet Kumar Verma
- Department of Chemistry, Dayalbagh Educational Institute, Dayalbagh, Agra 282005, Uttar Pradesh, India
| | - Dinesh Sah
- Department of Chemistry, Dayalbagh Educational Institute, Dayalbagh, Agra 282005, Uttar Pradesh, India
| | - Jitendra Dubey
- Department of Chemistry, Dayalbagh Educational Institute, Dayalbagh, Agra 282005, Uttar Pradesh, India
| | - K Maharaj Kumari
- Department of Chemistry, Dayalbagh Educational Institute, Dayalbagh, Agra 282005, Uttar Pradesh, India
| | - Anita Lakhani
- Department of Chemistry, Dayalbagh Educational Institute, Dayalbagh, Agra 282005, Uttar Pradesh, India
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Nadali A, Leili M, Bahrami A, Karami M, Afkhami A. Phase distribution and risk assessment of PAHs in ambient air of Hamadan, Iran. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 209:111807. [PMID: 33360291 DOI: 10.1016/j.ecoenv.2020.111807] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 12/05/2020] [Accepted: 12/12/2020] [Indexed: 05/27/2023]
Abstract
In the present study, both gaseous and particulate (PM with dae <2.5 µm) phases of polycyclic aromatic hydrocarbons (PAHs) were measured in the ambient air of Hamadan city, Iran. For this reason, two low-volume samplers equipped with glass fiber filters were used for sampling of particulate phase (N = 30) and XAD-2 sorbent tubes were applied for sampling gaseous phase of PAHs (N = 30). The sampling was conducted during warm and cold seasons in 2019. The average of cold/warm season ratios for Σ16PAH and PM concentrations were 1.14 and 0.62, respectively. Summed PAHs concentration were determined to be in the range 0.008-59.46 (mean: 11.61) ng/m3 and 0.05-40.83 (mean: 10.22) ng/m3 for the cold and warm seasons, respectively. A negative Pearson correlation coefficient was obtained for wind speed and relative humidity. The average Benzo (a) Pyrene equivalent carcinogenic (BaPeq) levels in the cold season were lower than the maximum permissible risk level of 1 ng/m3 for BaP. The BaP toxicity equivalency (ΣBaPTEQ) and BaP mutagenicity equivalency (ΣBaPMEQ) appeared to be significantly higher in the cold season (averaging 0.35 and 1.65 ng/m3, respectively) than those in warm season. Health risk assessment was performed for children and adults based on BaPeq, inhalation cancer risk. The diagnostic ratios of individual PAHs concentration showed that the significant sources of PAH emissions may be related to light duty vehicles (LDVs) in Hamadan. Although, some other sources such as pyrogenic source and petrol combustion were also suggested.
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Affiliation(s)
- Azam Nadali
- Department of Environmental Health Engineering, School of Public Health and Research Center for Health Sciences, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Mostafa Leili
- Department of Environmental Health Engineering, School of Public Health and Research Center for Health Sciences, Hamadan University of Medical Sciences, Hamadan, Iran.
| | - Abdolrahman Bahrami
- Department of Occupational Health, Faculty of Health, Hamadan University of Medical Sciences, Hamadan, Iran.
| | - Manoochehr Karami
- Department of Epidemiology, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran.
| | - Abbas Afkhami
- Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran.
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13
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Gurkan Ayyildiz E, Esen F. Atmospheric Polycyclic Aromatic Hydrocarbons (PAHs) at Two Sites, in Bursa, Turkey: Determination of Concentrations, Gas-Particle Partitioning, Sources, and Health Risk. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2020; 78:350-366. [PMID: 31901971 DOI: 10.1007/s00244-019-00698-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 12/16/2019] [Indexed: 06/10/2023]
Abstract
This study investigated the concentration of polycyclic aromatic hydrocarbons (PAHs) using particle and gas-phase air samples collected in the Ovaakca and Cumalikizik region of Bursa, between May and September 2017. The concentration of Σ16PAH measured in the gas phase, for Ovaakca and Cumalikizik, were 5.32 ± 1.98 and 4.91 ± 3.41 ng m-3, respectively; and for the particle phase, 0.81 ± 0.56 and 1.84 ± 1.82 ng m-3, respectively. The coefficient of gas-particle partitioning was related to the excessive cooled vapor pressure. The determined slope values were - 0.319 (Ovaakca) and - 0.505 (Cumalikizik), which showed the strong effect of organic carbon absorption and the distance to the equilibrium. These experimental values were compared with the results obtained using the octanol/air and Dual partition models, and Dual partition model showed more accurate values than the octanol/air model. The relations between temperature and concentration in the gas phase of PAHs were evaluated using the Clausius-Clapeyron equation. The results indicated the influence of long-range transport of the atmospheric concentrations of PAHs at the regions. Diagnostic ratio analysis showed that biomass burning, coal combustion, and vehicular emissions contributed greatly to the atmospheric PAHs in the regions. In principal component analysis analysis, wood-burning was found to be the predominant parameter in addition to PAH sources determined with diagnostic ratios. In this study, the lifetime risk of lung cancer was calculated according to the mean and max BaP-TEQ values. When calculated according to the average values, while both regions were acceptable risk levels (Ovaakca: 2.6 × 10-6 and Cumalikizik: 8.6 × 10-6), at low-risk level was determined according to max BaP-TEQ values only in the Cumalikizik region (1.93 × 10-5).
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Affiliation(s)
- Emine Gurkan Ayyildiz
- Department of Environmental Engineering, Faculty of Engineering, Bursa Uludag University, 16059, Nilufer, Bursa, Turkey
| | - Fatma Esen
- Department of Environmental Engineering, Faculty of Engineering, Bursa Uludag University, 16059, Nilufer, Bursa, Turkey.
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14
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Lammel G, Kitanovski Z, Kukučka P, Novák J, Arangio AM, Codling GP, Filippi A, Hovorka J, Kuta J, Leoni C, Příbylová P, Prokeš R, Sáňka O, Shahpoury P, Tong H, Wietzoreck M. Oxygenated and Nitrated Polycyclic Aromatic Hydrocarbons in Ambient Air-Levels, Phase Partitioning, Mass Size Distributions, and Inhalation Bioaccessibility. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:2615-2625. [PMID: 31950831 PMCID: PMC7307896 DOI: 10.1021/acs.est.9b06820] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 01/07/2020] [Accepted: 01/17/2020] [Indexed: 05/06/2023]
Abstract
Among the nitrated and oxygenated polycyclic aromatic hydrocarbons (NPAHs and OPAHs) are some of the most hazardous substances to public health, mainly because of their carcinogenicity and oxidative potential. Despite these concerns, the concentrations and fate of NPAHs and OPAHs in the atmospheric environment are largely unknown. Ambient air concentrations of 18 NPAHs, 5 quinones, and 5 other OPAHs were determined at two urban and one regional background sites in central Europe. At one of the urban sites, the total (gas and particulate) concentrations of Σ10OPAHs were 10.0 ± 9.2 ng/m3 in winter and 3.5 ± 1.6 ng/m3 in summer. The gradient to the regional background site exceeded 1 order of magnitude. Σ18NPAH concentrations were typically 1 order of magnitude lower than OPAHs. Among OPAHs, 9-fluorenone and (9,10)-anthraquinone were the most abundant species, accompanied by benzanthrone in winter. (9,10)-Anthraquinone represented two-thirds of quinones. We found that a large fraction of the target substance particulate mass was carried by submicrometer particles. The derived inhalation bioaccessibility in the PM10 size fraction is found to be ≈5% of the total ambient concentration of OPAHs and up to ≈2% for NPAHs. For 9-fluorenone and (9,10)-anthraquinone, up to 86 and 18%, respectively, were found at the rural site. Our results indicate that water solubility could function as a limiting factor for bioaccessibility of inhaled particulate NPAHs and OPAHs, without considerable effect of surfactant lipids and proteins in the lung lining fluid.
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Affiliation(s)
- Gerhard Lammel
- Research
Centre for Toxic Compounds in the Environment, Masaryk University, Brno 601 77, Czech Republic
- Multiphase
Chemistry Department, Max Planck Institute
for Chemistry, Mainz 55128, Germany
| | - Zoran Kitanovski
- Multiphase
Chemistry Department, Max Planck Institute
for Chemistry, Mainz 55128, Germany
| | - Petr Kukučka
- Research
Centre for Toxic Compounds in the Environment, Masaryk University, Brno 601 77, Czech Republic
| | - Jiří Novák
- Research
Centre for Toxic Compounds in the Environment, Masaryk University, Brno 601 77, Czech Republic
| | - Andrea M. Arangio
- Multiphase
Chemistry Department, Max Planck Institute
for Chemistry, Mainz 55128, Germany
| | - Garry P. Codling
- Research
Centre for Toxic Compounds in the Environment, Masaryk University, Brno 601 77, Czech Republic
| | - Alexander Filippi
- Multiphase
Chemistry Department, Max Planck Institute
for Chemistry, Mainz 55128, Germany
| | - Jan Hovorka
- Faculty
of Science, Institute for Environmental Studies, Charles University, Prague 116 36, Czech Republic
| | - Jan Kuta
- Research
Centre for Toxic Compounds in the Environment, Masaryk University, Brno 601 77, Czech Republic
| | - Cecilia Leoni
- Faculty
of Science, Institute for Environmental Studies, Charles University, Prague 116 36, Czech Republic
| | - Petra Příbylová
- Research
Centre for Toxic Compounds in the Environment, Masaryk University, Brno 601 77, Czech Republic
| | - Roman Prokeš
- Research
Centre for Toxic Compounds in the Environment, Masaryk University, Brno 601 77, Czech Republic
| | - Ondřej Sáňka
- Research
Centre for Toxic Compounds in the Environment, Masaryk University, Brno 601 77, Czech Republic
| | - Pourya Shahpoury
- Multiphase
Chemistry Department, Max Planck Institute
for Chemistry, Mainz 55128, Germany
- Air
Quality Processes Research Section, Environment
and Climate Change Canada, Toronto 12843, Canada
| | - Haijie Tong
- Multiphase
Chemistry Department, Max Planck Institute
for Chemistry, Mainz 55128, Germany
| | - Marco Wietzoreck
- Multiphase
Chemistry Department, Max Planck Institute
for Chemistry, Mainz 55128, Germany
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15
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Caliskan B, Kücük A, Tasdemir Y, Cindoruk SS. PAH levels in a furniture-manufacturing city atmosphere. CHEMOSPHERE 2020; 240:124757. [PMID: 31726607 DOI: 10.1016/j.chemosphere.2019.124757] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 08/31/2019] [Accepted: 09/03/2019] [Indexed: 06/10/2023]
Abstract
In this study, in order to determine atmospheric PAH concentrations in Inegol/Turkey, ambient air samples were collected from two different sites representing industrial and uncontrolled furniture manufacturers regions. Sampling campaign took place between December 2017 and November 2018. Air samples were collected using high volume air samplers (HVAS) and PAH concentrations were determined in both gas and particulate phases. The mean of the atmospheric PAH concentrations obtained in the gas phase in the furniture workshops (FW) and industrial district (ID) regions were 697.82 ± 637 ng/m3 and 772.92 ± 864.23 ng/m3, respectively. The concentrations in the particulate phase in the regions were 413.52 ± 430.23 ng/m3 and 342.40 ± 527.48 ng/m3, respectively. The average total (gas + particlulate phases) concentration of ∑16PAH determined in the site of FW was 1111.34 ± 1045.24 ng/m3 while that was 772.92 ± 864.23 ng/m3 in ID. These values are over the ambient levels reported for urban sites wherein big industries exist around the world. Additionally, the average of particle phase percentage was 30% because of nearby combustion sources. The determination of possible sources of PAHs in the regions was performed using principal component analysis (PCA). PCA results showed that the main sources of pollutants of the regions are intertwined (combustion, traffic, industries). However, the most effective source is thought to be uncontrolled combustion of furniture wastes as fuel for residential heating. Health risks for the citizens were calculated for both regions and were found not to be at high-class risk.
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Affiliation(s)
- Burak Caliskan
- Department of Environmental Engineering, Faculty of Engineering, Bursa Uludag University, 16059, Nilüfer, Bursa, Turkey
| | - Aleyna Kücük
- Department of Environmental Engineering, Faculty of Engineering, Bursa Uludag University, 16059, Nilüfer, Bursa, Turkey
| | - Yücel Tasdemir
- Department of Environmental Engineering, Faculty of Engineering, Bursa Uludag University, 16059, Nilüfer, Bursa, Turkey
| | - S Sıddık Cindoruk
- Department of Environmental Engineering, Faculty of Engineering, Bursa Uludag University, 16059, Nilüfer, Bursa, Turkey.
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16
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Sah D, Verma PK, Kandikonda MK, Lakhani A. Chemical fractionation, bioavailability, and health risks of heavy metals in fine particulate matter at a site in the Indo-Gangetic Plain, India. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:19749-19762. [PMID: 31089995 DOI: 10.1007/s11356-019-05144-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 04/08/2019] [Indexed: 06/09/2023]
Abstract
In the present study, the distribution and chemical fractionation of heavy metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in PM2.5 collected at Sikandarpur in Agra from September 2015 to February 2016 were carried out to evaluate their mobility potential, environmental, and human health risk through inhalation. Sequential extraction procedure was applied to partition the heavy metals into four fractions (soluble and exchangeable fraction (F1); carbonates, oxides, and reducible fraction (F2); bound to organic matter, oxidizable, and sulphidic fraction (F3); and residual fraction (F4)) in PM2.5 samples. The metals in each fraction were analyzed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Daily PM2.5 concentration ranged between 13 and 238 μg m-3 during the study period. For more than 92% of the days, the mass concentrations were greater than the National Ambient Air Quality Standard (NAAQS) set at 60 μg m-3. The total mass concentration of the eight metals was 3.3 μg m-3 that accounted for 2.5% of the PM2.5 mass concentration and followed the order Fe > Zn > Cu > Mn > Pb > Ni > Cd > Cr in dominance. The carcinogenic metals (Cd, Cr, Ni, and Pb) comprised 10% of the total metal determined. Almost all the metals had the highest proportion in the residual fraction (F4) except Ni, which had the highest proportion in the reducible fraction (F2). Chemical fractionation and contamination factor (CF) showed that Pb and Ni are readily mobilized and more bioavailable. Risk assessment code (RAC) showed that Cd, Cu, Mn, Ni, Pb, and Zn had medium environmental risk, while Cr and Fe had low risk. When the bioavailable (F1 + F2) concentrations were applied to calculate non-carcinogenic and carcinogenic risk, the results showed that the value of hazard index (HI) for toxic metals was 1.7 for both children and adults through inhalation. The integrated carcinogenic risk was 1.8 × 10-6 for children and 7.3 × 10-6 for adults, with both values being higher than the precautionary criterion (1 × 10-6). Enrichment factor (EF) calculations showed that Cd, Pb, Zn, and Ni were enriched being contributed by anthropogenic activities carried out in the industrial sectors of the city.
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Affiliation(s)
- Dinesh Sah
- Department of Chemistry, Faculty of Science, Dayalbagh Educational Institute, Dayalbagh, Agra (UP), Agra, India
| | - Puneet Kumar Verma
- Department of Chemistry, Faculty of Science, Dayalbagh Educational Institute, Dayalbagh, Agra (UP), Agra, India
| | - Maharaj Kumari Kandikonda
- Department of Chemistry, Faculty of Science, Dayalbagh Educational Institute, Dayalbagh, Agra (UP), Agra, India
| | - Anita Lakhani
- Department of Chemistry, Faculty of Science, Dayalbagh Educational Institute, Dayalbagh, Agra (UP), Agra, India.
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17
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Yadav IC, Devi NL, Li J, Zhang G. Altitudinal and spatial variations of polycyclic aromatic hydrocarbons in Nepal: Implications on source apportionment and risk assessment. CHEMOSPHERE 2018; 198:386-396. [PMID: 29421754 DOI: 10.1016/j.chemosphere.2018.01.075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 01/15/2018] [Accepted: 01/15/2018] [Indexed: 06/08/2023]
Abstract
Although several global/regional studies have detailed the high level of polycyclic aromatic hydrocarbons in urban areas worldwide, unfortunately, Nepal has never been part of any global/regional regular monitoring plan. Despite few sporadic studies exist, the systematic monitoring and integrated concentration of PAHs in urban region of Nepal are lacking. In this study, the concentrations, sources, and health risk assessment of 16 PAHs in air (n = 34) were investigated in suspected source areas/more densely populated regions of Nepal. Four potential source areas in Nepal were focused as it was conjectured that urban centers in plain areas (Birgunj and Biratnagar) would possibly be more influenced by PAHs as a result of intense biomass/crop residue burning than those in hilly areas (Kathmandu and Pokhara). The overall concentrations of ∑16PAHs ranged from 4.3 to 131 ng/m3 (median 33.3 ng/m3). ∑16PAH concentrations in plain areas were two folds higher than those in hilly areas. PHE was the most abundant followed by FLUA, PYR, and NAP, which accounted for 36%, 15%, 12%, and 9% of ∑16PAHs, respectively. Principal component analysis confirmed that PAHs in highly urbanized areas (Kathmandu and Pokhara) were related to diesel exhausts and coal combustion, while PAHs in less urbanized regions (Birgunj and Biratnagar) originated from biomass and domestic wood combustions. Furthermore, in the urban areas of Nepal, vehicular emission could also influence atmospheric PAHs. The lifetime cancer risk per million populations due to PAH exposures was estimated to be higher for plain areas than that for hilly areas, suggesting a relatively greater risk of cancer in people living in plain areas.
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Affiliation(s)
- Ishwar Chandra Yadav
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, PR China; Department of International Environmental and Agricultural Science (IEAS), Tokyo University of Agriculture and Technology (TUAT) 3-5-8, Saiwai-Cho, Fuchu, Tokyo, 1838509, Japan.
| | | | - Jun Li
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, PR China
| | - Gan Zhang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, PR China
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