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He Y, Wang X, Zhang Z. Polycyclic aromatic hydrocarbons (PAHs) in a sediment core from Lake Taihu and their associations with sedimentary organic matter. J Environ Sci (China) 2023; 129:79-89. [PMID: 36804244 DOI: 10.1016/j.jes.2022.09.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 09/02/2022] [Accepted: 09/10/2022] [Indexed: 06/18/2023]
Abstract
Sediment core is the recorder of polycyclic aromatic hydrocarbon (PAH) pollutions and the associated sedimentary organic matter (SOM), acting as crucial supports for pollution control and environmental management. Here, the sedimentary records of PAHs and SOM in the past century in Lake Taihu, China, were reconstructed from a 50-cm sediment core. On the one hand, the presence of PAHs ranged from 8.99 to 199.2 ng/g. Vertically, PAHs declined with the depth increased, and the sedimentation history of PAHs was divided into two stages with a discontinuity at 20 cm depth. In composition, PAHs in the sediment core were dominated by three-ring PAHs (44.6% ± 9.1%, mean ± standard deviation), and were followed by four-ring (27.0% ± 3.3%), and five-ring (12.1% ± 4.0%) PAHs. In toxicity assessment, the sedimentary records of benzo[a]pyrene-based toxic equivalency were well described by an exponential model with R-square of 0.95, and the environmental background toxic value was identified as 1.62 ng/g. On the other hand, different components of SOM were successfully identified by n-alkane markers (p < 0.01) and the variations of SOM were well explained (84.6%). A discontinuity of SOM was recognized at 22 cm depth. Association study showed that the sedimentary PAHs were associated with both anthropogenic and biogenic SOM (p < 0.05) with explained variances for most individual PAHs of 60%. It indicated the vertical distributions of PAHs were driven by sedimentary SOM. Therefore, environmental processes such as biogenic factors should attract more attentions as well as PAH emissions to reduce the impacts of PAHs.
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Affiliation(s)
- Yong He
- College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
| | - Xiangyu Wang
- College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Zhaobin Zhang
- College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
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Aralu CC, Okoye PAC, Abugu HO, Eboagu NC, Eze VC. Characterization, sources, and risk assessment of PAHs in borehole water from the vicinity of an unlined dumpsite in Awka, Nigeria. Sci Rep 2023; 13:9688. [PMID: 37322096 PMCID: PMC10272149 DOI: 10.1038/s41598-023-36691-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 06/08/2023] [Indexed: 06/17/2023] Open
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are contaminants of interest in the ecosystem due to associated health risks. Therefore, their detection in the environment is important. In this regard, the risk assessment of PAHs in borehole water near the unlined dumpsite in Anambra State was investigated. Samples of borehole water (16 each) were collected from the study and control areas during both seasons. The PAH concentrations in the borehole water samples were analyzed using gas chromatography. The mean PAH concentration in the study and control samples for the wet season varied from BL-7.65 µg/L to BL-2.98 µg/L, respectively. The study samples' dry season values ranged from BL to 3.33 µg/L, while control samples ranged from BL to 1.87 µg/L. [Formula: see text]PAHs for the wet and dry seasons varied from 5.8 to 13.94 µg/L and 4.25 to 10.09 µg/L for study and control samples, respectively. The four and five rings PAH were the most dominant group in the [Formula: see text] PAHs for the study and control samples, respectively. Diagnostic ratios suggested pyrolytic and petrogenic sources for both locations. The cluster analysis showed different sources of the congeners in the samples. The non-carcinogenic risk showed no possibility of risks via dermal and ingestion routes. In addition, the possibility of cancer risks via ingestion routes was doubtful. The carcinogenic risk index through dermal contact exceeded the acceptable limit for adults and is at a tolerable limit for children, indicating potential threats to humans, with adults more susceptible to cancer risks. Therefore, this study recommends that sanitary dumpsites be constructed for waste disposal and implementation of environmental laws to prevent underground water pollution and the environment.
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Affiliation(s)
| | | | - Hillary O Abugu
- Department of Pure and Industrial Chemistry, University of Nigeria, Nsukka, Nigeria
| | - Nkiruka C Eboagu
- Department of Pure and Industrial Chemistry, Nnamdi Azikiwe University, Awka, Nigeria
| | - Victor Chukwuemeka Eze
- Department of Pure and Industrial Chemistry, Nnamdi Azikiwe University, Awka, Nigeria.
- Department of Chemistry, University of Agriculture and Environmental Sciences, Umuagwo, Imo, Nigeria.
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Aigberua AO, Izah SC, Aigberua AA. Occurrence, source delineation, and health hazard of polycyclic aromatic hydrocarbons in tissues of Sarotherodon melanotheron and Chrysichthys nigrodigitatus from Okulu River, Nigeria. ENVIRONMENTAL MONITORING AND ASSESSMENT 2023; 195:364. [PMID: 36740655 DOI: 10.1007/s10661-023-10970-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: 06/02/2022] [Accepted: 01/27/2023] [Indexed: 06/18/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are mistakenly consumed by people through their diet, including food and water. The occurrence, source, and health hazards of 16 PAHs in 36 tilapia (Sarotherodon melanotheron) and silver catfish (Chrysichthys nigrodigitatus) samples from Okulu River, Nigeria were investigated in this study. The total PAH concentration ranged from 11.70-24.20 to 13.40-19.60 µg/kg, being statistically different between the two species. The values were higher than the European Commission limits of 12 µg/kg and within the World Health Organization limit of 20 µg/kg. The 16 PAHs were detected in both fish species. The diagnostic ratio revealed that petroleum, fossil fuel, and incomplete combustion of biomass wastes were the sources of PAHs in the fishes. Pearson's correlation showed that the PAHs can come from diverse sources. The non-carcinogenic risk quotients (HQs) and hazard index (HI) in both fish species were 1, an indication of no adverse health effects. Among the 9 PAHs that were used to calculate the HI, BaP and BgP accounted for 31% and 62%, respectively, for Chrysichthys nigrodigitatus, and 25% and 69%, respectively, for Sarotherodon melanotheron. The carcinogenic hazard of the 7 PAHs assessed was within the acceptable range of 10-6-10-4. But the sum of the carcinogenic hazard was on the order of 10-3 in both species of fish, an indication of carcinogenic health effects. 79% and 75% of the total carcinogenic risk for Chrysichthys nigrodigitatus and Sarotherodon melanotheron, respectively, are from DaA and InP. The consumption of PAHs by residents of the study area and other population groups through fish foods from the studied river underlines the importance of checking PAHs in aquatic foods for health concerns on a frequent basis.
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Affiliation(s)
- Ayobami Omozemoje Aigberua
- Department of Environment, Research and Development, Anal Concept Limited, Elelenwo, Rivers State, Nigeria
| | | | - Ayotunde Aigboje Aigberua
- Department of Geography and Environmental Management, University of Port Harcourt,, Rivers State, Nigeria
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Teodora Ciucure C, Geana EI, Lidia Chitescu C, Laurentiu Badea S, Elena Ionete R. Distribution, sources and ecological risk assessment of polycyclic aromatic hydrocarbons in waters and sediments from Olt River dam reservoirs in Romania. CHEMOSPHERE 2023; 311:137024. [PMID: 36323388 DOI: 10.1016/j.chemosphere.2022.137024] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 09/23/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
This study provides important data on the distribution, sources and ecological risks of polycyclic aromatic hydrocarbons (PAHs), in surface waters and sediments collected from dam reservoirs on middle and lower course of the Olt River, the main tributary of the Danube, until the discharge into the Black Sea. A wide variation range of total PAHs concentrations in water (from 1.3 to 46.2 ng/L) and sediment (from 1.78 to 614.04 μg/kg) samples was emphasized by the results. The highest average PAHs concentration in water was recorded in the cold season and the lowest in the summer. In sediments, no differences were observed depending on the sampling period. Spatial distribution of PAHs in waters and sediments was correlated with the main anthropogenic activities along the river course. Regardless of the method used to attribute PAH sources (diagnostic ratios of specific PAHs, principal component analysis and hierarchical cluster analysis), it was confirmed that the potential anthropogenic sources of PAHs were both pyrogenic (incomplete combustion of biomass and coal) and pyrolytic (incomplete combustion of liquid fossil fuels and vehicle exhaust emissions), with a dominant pyrolytic input. Ecological risk assessment based on environmental quality standards, mean effect range-median quotient (m-ERM-Q), toxic equivalency factors (TEFs) and risk quotient (RQ) methods indicated potentially low ecological risks from PAHs. The ecological status of the Olt river waters poses no potential risk, and pollution of surface sediments can be classified as low polluted, except for two sites near industrial activities classified as moderately polluted. Therefore, a regular monitoring of PAHs concentration in the waters and sediments should be performed to prevent further contamination of PAHs in the studied area, especially in densely populated industrial areas.
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Affiliation(s)
- Corina Teodora Ciucure
- National Research and Development Institute for Cryogenics and Isotopic Technologies - ICSI Rm. Valcea, Romania
| | - Elisabeta-Irina Geana
- National Research and Development Institute for Cryogenics and Isotopic Technologies - ICSI Rm. Valcea, Romania.
| | - Carmen Lidia Chitescu
- Dunarea de Jos" University of Galaţi, Faculty of Medicine and Pharmacy, 35 A.I. Cuza Str., 800010, Galaţi, Romania
| | - Silviu Laurentiu Badea
- National Research and Development Institute for Cryogenics and Isotopic Technologies - ICSI Rm. Valcea, Romania
| | - Roxana Elena Ionete
- National Research and Development Institute for Cryogenics and Isotopic Technologies - ICSI Rm. Valcea, Romania
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Mohammed R, Zhang ZF, Hu YH, Jiang C, He ZQ, Wang WJ, Li YF. Temporal-spatial variation, source forensics of PAHs and their derivatives in sediment from Songhua River, Northeastern China. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2022; 44:4031-4043. [PMID: 34820731 DOI: 10.1007/s10653-021-01106-7] [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: 03/08/2021] [Accepted: 09/17/2021] [Indexed: 06/13/2023]
Abstract
The distribution patterns and health risk assessment of nitrated polycyclic aromatic hydrocarbons (NPAHs), hydroxy polycyclic aromatic hydrocarbons (OH-PAHs), and regular 16 priority polycyclic aromatic hydrocarbons (PAHs) in sediment from the Songhua River in northeastern China were investigated in this research. During dry seasons, concentrations of 16 USEPA priority PAHs, OH-PAHs, and NPAHs were extremely high, with average values of 1220 ± 288, 317 ± 641, 2.54 ± 3.98, and 12.2 ± 22.1 ng/g (dry weight, dw). The dry period level was confirmed to be 4 times greater than the wet period concentration. Modeling with positive matrix factorization (PMF) and estimation of diagnostic isomeric ratios were applied for identifying sources, according to the positive matrix factorization model: vehicle emissions (38.1%), biomass burning (25%), petroleum source (23.4%), and diesel engines source (13.5%) in wet season as well as wood combustion (44.1%), vehicle source (40.2%), coke oven (10.8%), and biomass burning (4.9%) in the dry season. The greatest seasonal variability was attributed to high molecular weight compounds (HMW PAHs). BaP was confirmed to be 81% carcinogenic in this study, which offers convincing proof of the escalating health issues.
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Affiliation(s)
- Rashid Mohammed
- State Key Laboratory of Urban Water Resource and Environment, International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), Harbin Institute of Technology, Harbin, 150090, Heilongjiang, China
- International Joint Research Center for Arctic Environment and Ecosystem (IJRC-AEE), Harbin Institute of Technology, Polar Academy, Harbin, 150090, China
- Heilongjiang Provincial Key Laboratory of Polar Environment and Ecosystem (HPKL-PEE), Harbin Institute of Technology (HIT), Harbin, 150090, China
| | - Zi-Feng Zhang
- State Key Laboratory of Urban Water Resource and Environment, International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), Harbin Institute of Technology, Harbin, 150090, Heilongjiang, China.
- International Joint Research Center for Arctic Environment and Ecosystem (IJRC-AEE), Harbin Institute of Technology, Polar Academy, Harbin, 150090, China.
- Heilongjiang Provincial Key Laboratory of Polar Environment and Ecosystem (HPKL-PEE), Harbin Institute of Technology (HIT), Harbin, 150090, China.
| | - Ying-Hua Hu
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), Heilongjiang Institute of Labor Hygiene and Occupational Diseases, Harbin, 150028, China
| | - Chao Jiang
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), Heilongjiang Institute of Labor Hygiene and Occupational Diseases, Harbin, 150028, China
| | - Zhi-Qiang He
- Heilongjiang Pony Testing Technical Co.,Ltd, Harbin, 150028, Heilongjiang, China
| | - Wen-Juan Wang
- Heilongjiang Pony Testing Technical Co.,Ltd, Harbin, 150028, Heilongjiang, China
| | - Yi-Fan Li
- State Key Laboratory of Urban Water Resource and Environment, International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), Harbin Institute of Technology, Harbin, 150090, Heilongjiang, China
- International Joint Research Center for Arctic Environment and Ecosystem (IJRC-AEE), Harbin Institute of Technology, Polar Academy, Harbin, 150090, China
- Heilongjiang Provincial Key Laboratory of Polar Environment and Ecosystem (HPKL-PEE), Harbin Institute of Technology (HIT), Harbin, 150090, China
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Tepe Y, Aydın H, Ustaoğlu F, Kaya S. Seasonal distribution and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in surface sediments from the Giresun coast of southeastern Black Sea. MARINE POLLUTION BULLETIN 2022; 178:113585. [PMID: 35339061 DOI: 10.1016/j.marpolbul.2022.113585] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 03/13/2022] [Accepted: 03/17/2022] [Indexed: 06/14/2023]
Abstract
Seasonal sediment samples were collected along the Giresun coastline of southeastern Black Sea and analyzed to detect the levels of 16 polycyclic aromatic hydrocarbons (PAHs). The PAH levels, ranging from 28.47 to 444.36 ng g-1 with the mean of 102.57 ng g-1 remained lower than those detected in most of the other sediment studies conducted worldwide. The percentage of three-ring PAHs (38.9%) was rather high, followed by that of 5-ring PAHs (21.8%). Detection rates revealed that PAHs in surface sediments along the Giresun coastline are mainly associated with coal combustion and local emissions. The evaluation with sediment quality guidelines (SQGs) showed that the level of PAHs was comparable to that at which the risk of adverse biological effects cannot be ruled out (≥TEL and <PEL) in some stations. The risk posed by PAHs in Giresun coastal sediments appears to be low to moderate ecological risk according to the risk quotient.
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Affiliation(s)
- Yalçın Tepe
- Department of Biology, Faculty of Arts and Science, Giresun University, Güre Campus, 28200 Giresun, Turkey.
| | - Handan Aydın
- Department of Biology, Faculty of Arts and Science, Giresun University, Güre Campus, 28200 Giresun, Turkey
| | - Fikret Ustaoğlu
- Department of Biology, Faculty of Arts and Science, Giresun University, Güre Campus, 28200 Giresun, Turkey
| | - Serdal Kaya
- Department of Aeronautical Engineering, Faculty of Aviation and Space Sciences, Necmettin Erbakan University, 42090 Konya, Turkey
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Fate and Occurrence of Polycyclic Aromatic Hydrocarbons and Their Derivatives in Water and Sediment from Songhua River, Northeast China. WATER 2021. [DOI: 10.3390/w13091196] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The Songhua River is one of the most populated and oldest industrial areas in Northeast China. To understand the sources and distribution of polycyclic aromatic hydrocarbons and their derivatives, such as 16 priority (PAHs), 33 methylated (Me-PAHs), and 12 nitrated (NPAHs) in river water and sediment, were noticed. The concentrations of ∑PAHs, ∑Me-PAHs, and ∑NPAHs in river water scaled from 135 to 563, 9.36 to 711, and 1.26 to 64.7 ng L−1, with mean values of 286, 310, and 17.9 ng L−1, and those in sediments were from 35.8 to 2000 ng g−1, 0.62 to 394 ng g−1, and 0.28 to 176 ng g−1 (dry weight) with mean values of 283, 103, and 21.7 ng g−1. The compositions proved that two-ring and three-ring compounds of PAHs, NPAHs, and four-ring, six-ring of Me-PAHs were prevalent in water samples; in contrast, four-ring dominated in sediments. Principal components analysis (PCA) and diagnostic ratios confirmed that pollutant source was mixed petrogenic and pyrogenic origin. The fugacity fraction (ƒƒ) was also calculated to explain the trend of sediment–water exchange, high ƒƒ values found in summer, for most HMW PAHs and Me-PAHs that these substances acted as a secondary source of emissions from sediment to water. The risk assessment for water was categorized as high.
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Idowu O, Carbery M, O'Connor W, Thavamani P. Speciation and source apportionment of polycyclic aromatic compounds (PACs) in sediments of the largest salt water lake of Australia. CHEMOSPHERE 2020; 246:125779. [PMID: 31927372 DOI: 10.1016/j.chemosphere.2019.125779] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 12/25/2019] [Accepted: 12/27/2019] [Indexed: 06/10/2023]
Abstract
Great ecological and human health risks may arise from the presence of polycyclic aromatic hydrocarbons (PAHs) in aquatic environments and particularly in sediments, where they often partition. In spite of the apparent risk, knowledge about PAHs and their polar derivatives in sediments is limited. We, therefore, carried out an assessment of the concentrations of parent PAHs and their derivatives (polar PAHs) in sediments of Lake Macquarie: the largest saltwater lake in the southern hemisphere. A total of 31 sediment samples along the pollution prone western shoreline of the estuary were analysed. Multiple source apportionment methods were used to investigate PAH sources contributing to parent and polar PAH concentrations in the estuarine sediments. Concentration levels were highest for high molecular weight (HMW) PAHs compared to low molecular weight (LMW) PAHs. The highest PAH concentrations were recorded for oxygenated PAHs (oxy-PAHs) compared to parent and other polar PAHs. Polycyclic aromatic hydrocarbon diagnostic ratios and compositional analysis showed that PAHs in Lake Macquarie were predominantly pyrogenic exhibiting strong positive correlation (R2 = 0.972) with total PAH concentrations. Principal Component Analysis (PCA) identified three groupings of PAHs with oxy-PAHs and NPAHs dominating (40.2%). Carbazole, a heterocyclic PAH, was also a prominent contributor to sediment PAH concentrations. Atmospheric deposition, coal combustion and vehicular emissions were implicated as the major contributors to sediment pollution.
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Affiliation(s)
- Oluyoye Idowu
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW, 2308, Australia
| | - Maddison Carbery
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW, 2308, Australia
| | - Wayne O'Connor
- Port Stephens Fisheries Institute, NSW Department of Primary Industries, Port Stephens, NSW, 2316, Australia
| | - Palanisami Thavamani
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW, 2308, Australia; Global Innovative Centre for Advanced Nanomaterials (GICAN), University of Newcastle, Callaghan, NSW, 2308, Australia.
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Polycyclic aromatic hydrocarbons in the bottom sediments of Elburgon River—Kenya: precursors for cancer. SN APPLIED SCIENCES 2019. [DOI: 10.1007/s42452-019-1321-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022] Open
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Adeniji AO, Okoh OO, Okoh AI. Levels of Polycyclic Aromatic Hydrocarbons in the Water and Sediment of Buffalo River Estuary, South Africa and Their Health Risk Assessment. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2019; 76:657-669. [PMID: 30879120 PMCID: PMC6469821 DOI: 10.1007/s00244-019-00617-w] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 03/04/2019] [Indexed: 05/04/2023]
Abstract
The incidence and spatial distribution of polycyclic aromatic hydrocarbons (PAHs) in the Buffalo River Estuary in the Eastern Cape Province of South Africa were assessed in this study. A total of 60 surface water and 19 sediment samples were collected from 5 sites of the estuary over a period of 6 months (December 2015 to May 2016). Extraction of PAHs from the water and sediment samples was achieved by using liquid-liquid and soxhlet extraction methods respectively, followed by column clean up with silica gel and quantification by gas chromatography-flame ionization detection. Individual PAH levels in the water and sediment samples ranged from not detected (ND) to 24.91 μg/L and ND to 7792 μg/kg, respectively. Total concentrations of the PAHs in the water and sediment samples varied as 14.91-206 μg/L and 1107-22,310 μg/kg in that order. Total levels of the contaminants were above the target values in the two matrices and were higher in summer than autumn. Although the noncarcinogenic risk of PAHs estimated in the water column through dermal absorption was very low compared with the target value, the carcinogenic risk determined was high for both adults and children. Similarly, benzo(a)pyrene and dibenzo(a,h)anthracene were found to be of higher carcinogenic and mutagenic risks in the sediments collected from the study area. Diagnostic ratios suggest that the target hydrocarbons are predominantly from pyrolytic sources. It therefore could be inferred that the water body is conspicuously polluted; hence, efforts should be made to control all the activities contributing to such magnitude of pollution at the sites.
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Affiliation(s)
- A O Adeniji
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, 5700, South Africa.
- Department of Chemistry, University of Fort Hare, Alice, 5700, South Africa.
| | - O O Okoh
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, 5700, South Africa
- Department of Chemistry, University of Fort Hare, Alice, 5700, South Africa
| | - A I Okoh
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, 5700, South Africa
- Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, Alice, 5700, South Africa
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