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Gao H, Li H, Shi J, Huang J, Wei J, Qu X, Long T. Black carbon, soil organic matter molecular signatures under different land uses in Shenyang, China and relationship with PAHs. CHEMOSPHERE 2023; 342:140089. [PMID: 37683951 DOI: 10.1016/j.chemosphere.2023.140089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 08/30/2023] [Accepted: 09/04/2023] [Indexed: 09/10/2023]
Abstract
The content, composition and molecular signatures of soil organic matter (SOM) have important influences on the cycle of soil organic carbon (SOC) and the partitioning of polycyclic aromatic hydrocarbons (PAHs) in soil. Seventy-nine soil samples from farmland, forest and urban areas were collected in Shenyang, China to investigate black carbon (BC) content, SOM molecular signatures varied with land use patterns, as well as the relationship with PAHs. The content of BC in urban soils was significantly higher than that of farmland and forest. BC was a key contributor of urban SOM which accounted for 0.35 ± 0.31 of SOC in urban soil. Based on BC/SOC ratio, the main sources of BC were identified as fossil fuel combustion for urban soils, while for farmland and forest soils, it is the mixed results of fossil fuel combustion and biomass burning. All categories of PAHs in urban soils showed the highest level compared to farmland and forest soils. Pearson's correlation analysis results showed there were significant positive correlations between BC and PAHs categories in urban soils, indicating the important role of BC in the accumulation of PAHs in soil. SOM from each of the two different land use patterns can be distinguished by molecular signatures. Urban SOM had abundant molecular markers derived from condensed organic carbon inputs, which was consistent with the BC/SOC value. Farmland SOM had abundant carbon from vegetation and microorganisms, and forest SOM was rich in organic carbon from fresh plant materials. The markers enriched in urban SOM showed significant correlations with most PAHs categories, highlighting the affinity of urban SOM for PAHs at the molecular level. This study contributed to understanding the impact of land management methods on SOM molecular composition signatures and its influence on PAHs occurrence in soil, providing a theoretical basis for regional soil pollution management.
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Affiliation(s)
- Han Gao
- State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control, Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment of China, Nanjing, Jiangsu, 210042, China; State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, 210023, China
| | - Huixin Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, 210023, China
| | - Jiaqi Shi
- State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control, Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment of China, Nanjing, Jiangsu, 210042, China
| | - Jianbo Huang
- State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control, Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment of China, Nanjing, Jiangsu, 210042, China
| | - Jing Wei
- State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control, Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment of China, Nanjing, Jiangsu, 210042, China
| | - Xiaolei Qu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, 210023, China
| | - Tao Long
- State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control, Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment of China, Nanjing, Jiangsu, 210042, China.
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Eckdahl JA, Rodriguez PC, Kristensen JA, Metcalfe DB, Ljung K. Mineral Soils Are an Important Intermediate Storage Pool of Black Carbon in Fennoscandian Boreal Forests. GLOBAL BIOGEOCHEMICAL CYCLES 2022; 36:e2022GB007489. [PMID: 36582662 PMCID: PMC9787418 DOI: 10.1029/2022gb007489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 09/08/2022] [Accepted: 11/07/2022] [Indexed: 05/14/2023]
Abstract
Approximately 40% of earth's carbon (C) stored in land vegetation and soil is within the boreal region. This large C pool is subjected to substantial removals and transformations during periodic wildfire. Fire-altered C, commonly known as pyrogenic carbon (PyC), plays a significant role in forest ecosystem functioning and composes a considerable fraction of C transport to limnic and oceanic sediments. While PyC stores are beginning to be quantified globally, knowledge is lacking regarding the drivers of their production and transport across ecosystems. This study used the chemo-thermal oxidation at 375°C (CTO-375) method to isolate a particularly refractory subset of PyC compounds, here called black carbon (BC), finding an average increase of 11.6 g BC m-2 at 1 year postfire in 50 separate wildfires occurring in Sweden during 2018. These increases could not be linked to proposed drivers, however BC storage in 50 additional nearby unburnt soils related strongly to soil mass while its proportion of the larger C pool related negatively to soil C:N. Fire approximately doubled BC stocks in the mineral layer but had no significant effect on BC in the organic layer where it was likely produced. Suppressed decomposition rates and low heating during fire in mineral subsoil relative to upper layers suggests potential removals of the doubled mineral layer BC are more likely transported out of the soil system than degraded in situ. Therefore, mineral soils are suggested to be an important storage pool for BC that can buffer short-term (production in fire) and long-term (cross-ecosystem transport) BC cycling.
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Affiliation(s)
- Johan A. Eckdahl
- Department of Physical Geography and Ecosystem ScienceLund UniversityLundSweden
- Department of Ecology and Environmental ScienceUmeå UniversityUmeåSweden
| | | | - Jeppe A. Kristensen
- Environmental Change InstituteSchool of Geography and the EnvironmentUniversity of OxfordOxfordUK
| | - Daniel B. Metcalfe
- Department of Ecology and Environmental ScienceUmeå UniversityUmeåSweden
| | - Karl Ljung
- Department of GeologyLund UniversityLundSweden
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Ljung K, Schoon PL, Rudolf M, Charrieau LM, Ni S, Filipsson HL. Recent Increased Loading of Carbonaceous Pollution from Biomass Burning in the Baltic Sea. ACS OMEGA 2022; 7:35102-35108. [PMID: 36211069 PMCID: PMC9535721 DOI: 10.1021/acsomega.2c04009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 09/14/2022] [Indexed: 06/16/2023]
Abstract
Black carbon (BC), spheroidal carbonaceous particles (SCP), and polycyclic aromatic hydrocarbons (PAH) are carbonaceous pollutants affecting the climate, environment, and human health. International regulations limit their emissions, and the present emissions are followed by monitoring programs. However, the monitoring programs have limited spatio-temporal coverage and only span the last decades. We can extend the knowledge of historical emission rates by measuring pollution levels in radiometrically dated marine and lacustrine sediment sequences. Here we present measurements of BC, SCP, and PAH from a sediment sequence sampled in the Öresund strait, between Denmark and Sweden and dated back to CE 1850. Our data show a massive increase in the burial rates of all measured pollutants starting in the 1940s. The pollution deposition peaked in the 1970-1980s and declined through the 1990s. However, the declining trend was reversed in the 2000s. Source appointment of PAHs shows a relatively higher contribution of emissions from wood-burning since CE 2000. This coincides with a change towards the increased use of biomass for both municipal and regional energy production in Scandinavia. Our results demonstrate that changes in energy production have caused changes in the delivery of carbonaceous pollution to marine environments. The increase in particle emissions from wood burning is potentially posing a future environmental and health risk.
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Wang Y, Paul SM, Jocher M, Espic C, Alewell C, Szidat S, Leifeld J. Soil carbon loss from drained agricultural peatland after coverage with mineral soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 800:149498. [PMID: 34426363 DOI: 10.1016/j.scitotenv.2021.149498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 07/15/2021] [Accepted: 08/02/2021] [Indexed: 06/13/2023]
Abstract
Drainage for agriculture has turned peatlands from a net sink to a net source of carbon (C). In order to reduce the environmental footprint of agricultural peatland drainage, and to counteract soil subsidence, mineral soil coverage is becoming an increasingly used practice in Switzerland. To explore the effect of mineral soil coverage on soil C loss and the source of CO2 from peatland drained for agriculture, we utilized the radiocarbon signature (F14C) of soil C and emitted CO2 in the field. The experiment, located in the Swiss Rhine Valley, was carried out on two adjacent drained organic soils, either without mineral soil cover (reference 'Ref'), or covered with mineral soil (thickness ~ 40 cm) (coverage 'Cov') 13 years ago. Drainage already commenced 130 years ago and the site was managed as meadow since the 1970ies. Drainage induced 41-75 kg C m-2 loss, which is equivalent to annual C loss rates of 0.49-0.58 kg C m-2 yr-1 and 0.31-0.63 kg C m-2 yr-1 for Cov and Ref, respectively. Mineral soil coverage had no significant effect on the amount of heterotrophic respiration, however, at Cov, the radiocarbon signature of heterotrophic CO2 was significantly (p<0.01) younger than at Ref, indicating that mineral soil coverage moved the source of decomposition of soil organic carbon (SOC) from a higher share of old peat towards a higher share of relatively younger material. In summary, our study lends support to the hypothesis that mineral soil coverage might reduce the decomposition of old peat underneath, and may therefore be a promising peatland management technique for the future use of drained peatland for agriculture.
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Affiliation(s)
- Yuqiao Wang
- Climate and Agriculture Group, Agroscope, Reckenholzstrasse 191, 8046 Zürich, Switzerland; Environmental Geosciences, University of Basel, Bernoullistrasse 30, 4056 Basel, Switzerland.
| | - Sonja M Paul
- Climate and Agriculture Group, Agroscope, Reckenholzstrasse 191, 8046 Zürich, Switzerland
| | - Markus Jocher
- Climate and Agriculture Group, Agroscope, Reckenholzstrasse 191, 8046 Zürich, Switzerland
| | - Christophe Espic
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland; Oeschger Centre for Climate Change Research, University of Bern, Hochschulstrasse 4, 3012 Bern, Switzerland
| | - Christine Alewell
- Environmental Geosciences, University of Basel, Bernoullistrasse 30, 4056 Basel, Switzerland
| | - Sönke Szidat
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland; Oeschger Centre for Climate Change Research, University of Bern, Hochschulstrasse 4, 3012 Bern, Switzerland
| | - Jens Leifeld
- Climate and Agriculture Group, Agroscope, Reckenholzstrasse 191, 8046 Zürich, Switzerland
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Min X, Wu J, Lu J, Wen X, Gao C, Li L. Distribution of Black Carbon in Topsoils of the Northeastern Qinghai-Tibet Plateau Under Natural and Anthropogenic Influences. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2019; 76:528-539. [PMID: 30610253 DOI: 10.1007/s00244-018-00595-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Accepted: 12/29/2018] [Indexed: 06/09/2023]
Abstract
Black carbon (BC), ubiquitous in soils, plays an important role in global carbon cycles, the radiative heat balance of the Earth, pollutant fate, emissions of greenhouse gas, soil fertility, soil microbial community, and ecosystem stability. However, information on BC in topsoils of the northeastern Qinghai-Tibet Plateau is limited. Therefore, this study performed field sampling and analyzed contents of total BC and soot BC in topsoils. The results indicated that the contents of total BC in all soil samples ranged from 0.504 to 74.381 g kg-1 with an average value of 5.152 g kg-1, whereas those of soot BC were in the range of 0.400-15.200 g kg-1 with a mean value of 1.719 g kg-1. Contents of BC were significantly correlated with those of total carbon and total organic carbon. Soil types affected the distribution of soil BC. The contents of total BC in the loam soils were larger than those in the clay soils, whereas soot BC was more easily enriched in the clay soils. Total BC was negatively correlated with Ca, and soot BC was negatively correlated with Ti. The contents of soil BC in functional areas, such as agricultural and pastoral areas, industrial areas, and mining areas, were significantly higher than those in other areas, illustrating that anthropogenic activities drastically affected the distribution of soil BC. This study exhibits the fundamental information on soil BC in the northeastern Qinghai-Tibet Plateau to provide important knowledge on global soil carbon sink.
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Affiliation(s)
- Xiuyun Min
- Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, 810008, Qinghai, China
- Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes, Xining, 810008, Qinghai, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jun Wu
- Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, 810008, Qinghai, China.
- Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes, Xining, 810008, Qinghai, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Jian Lu
- University of Chinese Academy of Sciences, Beijing, 100049, China
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, Shandong, China
| | - Xiaohu Wen
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, Gansu, China
| | - Chunliang Gao
- Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, 810008, Qinghai, China
- Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes, Xining, 810008, Qinghai, China
| | - Leiming Li
- Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, 810008, Qinghai, China
- Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes, Xining, 810008, Qinghai, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
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Ansari S, Waheed S, Ali U, Jones KC, Sweetman AJ, Halsall C, Malik RN. Assessing residual status and spatial variation of current-use pesticides under the influence of environmental factors in major cash crop growing areas of Pakistan. CHEMOSPHERE 2018; 212:486-496. [PMID: 30165276 DOI: 10.1016/j.chemosphere.2018.07.164] [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: 03/22/2018] [Revised: 07/26/2018] [Accepted: 07/27/2018] [Indexed: 06/08/2023]
Abstract
The status of seven currently used pesticides were assessed under the influence of soil parameters in surface soils of cash crop growing areas of Pakistan. Chlorpyrifos occurred in highest mean concentration (1.18 mg kg-1). Selected pesticides exhibited higher affinity towards both organic carbon and black carbon fractions. The δ13C stable carbon isotopic fraction of inorganic carbon was also used as a tracer and disclosed high retention of total organic carbon in Swat and Swabi sites. Statistical analysis revealed that carbon storage was primarily influenced by altitude and temperature. Soil clay mineral oxides of aluminum and iron positively correlated with organic carbon and selected pesticides (chlorpyrifos and cyprodinil). Soil to plant bio-concentration ratios predicted heightened uptake of azinfos and diazinon in major cash crop bio mass. Occupational risk via soil ingestion expressed no significant threat to the farmer community.
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Affiliation(s)
- Sundas Ansari
- Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Sidra Waheed
- Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Usman Ali
- Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Kevin C Jones
- Centre for Chemicals Management, Lancaster Environment Centre, Lancaster University, 12 Bailrigg, Lancaster LA1 4YQ, UK
| | - Andrew James Sweetman
- Centre for Chemicals Management, Lancaster Environment Centre, Lancaster University, 12 Bailrigg, Lancaster LA1 4YQ, UK
| | - Crispin Halsall
- Centre for Chemicals Management, Lancaster Environment Centre, Lancaster University, 12 Bailrigg, Lancaster LA1 4YQ, UK
| | - Riffat Naseem Malik
- Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan.
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7
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Bartolomé N, Hilber I, Sosa D, Schulin R, Mayer P, Bucheli TD. Applying no-depletion equilibrium sampling and full-depletion bioaccessibility extraction to 35 historically polycyclic aromatic hydrocarbon contaminated soils. CHEMOSPHERE 2018; 199:409-416. [PMID: 29453067 DOI: 10.1016/j.chemosphere.2018.01.159] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 01/25/2018] [Accepted: 01/28/2018] [Indexed: 06/08/2023]
Abstract
Assessing the bioaccessibility of organic pollutants in contaminated soils is considered a complement to measurements of total concentrations in risk assessment and legislation. Consequently, methods for its quantification require validation with historically contaminated soils. In this study, 35 such soils were obtained from various locations in Switzerland and Cuba. They were exposed to different pollution sources (e.g., pyrogenic and petrogenic) at various distance (i.e., urban to rural) and were subject to different land use (e.g., urban gardening and forest). Passive equilibrium sampling with polyoxymethylene was used to determine freely dissolved concentrations (Cfree) of polycyclic aromatic hydrocarbons (PAHs), while sorptive bioaccessibility extraction (SBE) with silicone rods was used to determine the bioaccessible PAH concentrations (Cbioacc) of these soils. The organic carbon partition coefficients of the soils were highest for skeet soils, followed by traffic, urban garden and rural soils. Lowest values were obtained from soil exposed to petrogenic sources. Applicability of SBE to quantify Cbioacc was restricted by silicone rod sorption capacity, as expressed quantitatively by the Sorption Capacity Ratio (SCR); particularly for soils with very high KD. The source of contamination determined bioaccessible fractions (fbioacc). The smallest fbioacc were obtained with skeet soils (15%), followed by the pyrogenically influenced soils, rural soils, and finally, the petrogenically contaminated soil (71%). In conclusion, we present the potential and limitations of the SBE method to quantify bioaccessibility in real soils. These results can be used for additional development of this and similar bioaccessibility methods to guarantee sufficient sorption capacity to obtain reliable results.
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Affiliation(s)
- Nora Bartolomé
- Agroscope, Environmental Analytics, Reckenholzstrasse 191, 8046, Zurich, Switzerland; Department of Environmental System Science, ETH Zurich, Universitätstrasse 16, 8092 Zurich, Switzerland
| | - Isabel Hilber
- Agroscope, Environmental Analytics, Reckenholzstrasse 191, 8046, Zurich, Switzerland
| | - Dayana Sosa
- Centro Nacional de Sanidad Agropecuaria (CENSA), Apartado 10, CP 32700, San José de las Lajas, Mayabeque, Cuba
| | - Rainer Schulin
- Department of Environmental System Science, ETH Zurich, Universitätstrasse 16, 8092 Zurich, Switzerland
| | - Philipp Mayer
- Technical University of Denmark, 2800 Kongens, Lyngby, Denmark
| | - Thomas D Bucheli
- Agroscope, Environmental Analytics, Reckenholzstrasse 191, 8046, Zurich, Switzerland.
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Qi F, Naidu R, Bolan NS, Dong Z, Yan Y, Lamb D, Bucheli TD, Choppala G, Duan L, Semple KT. Pyrogenic carbon in Australian soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 586:849-857. [PMID: 28215804 DOI: 10.1016/j.scitotenv.2017.02.064] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Revised: 02/06/2017] [Accepted: 02/07/2017] [Indexed: 06/06/2023]
Abstract
Pyrogenic carbon (PyC), the combustion residues of fossil fuel and biomass, is a versatile soil fraction active in biogeochemical processes. In this study, the chemo-thermal oxidation method (CTO-375) was applied to investigate the content and distribution of PyC in 30 Australian agricultural, pastoral, bushland and parkland soil with various soil types. Soils were sampled incrementally to 50cm in 6 locations and at another 7 locations at 0-10cm. Results showed that PyC in Australian soils typically ranged from 0.27-5.62mg/g, with three Dermosol soils ranging within 2.58-5.62mg/g. Soil PyC contributed 2.0-11% (N=29) to the total organic carbon (TOC), with one Ferrosol as high as 26%. PyC was concentrated either in the top (0-10cm) or bottom (30-50cm) soil layers, with the highest PyC:TOC ratio in the bottom (30-50cm) soil horizon in all soils. Principal component analysis - multiple linear regression (PCA-MLR) suggested the silt-associated organic C factor accounted for 38.5% of the variation in PyC. Our findings suggest that PyC is an important fraction of the TOC (2.0-11%, N=18) and chemically recalcitrant organic C (ROC) obtained by chemical C fractionation method accounts for a significant proportion of soil TOC (47.3-84.9%, N=18). This is the first study comparing these two methods, and it indicates both CTO-375 and C speciation methods can determine a fraction of recalcitrant organic C. However, estimated chemically recalcitrant organic carbon pool (ROC) was approximately an order of magnitude greater than that of thermally stable organic carbon (PyC).
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Affiliation(s)
- Fangjie Qi
- Global Centre for Environmental Research, ATC Building, Faculty of Science and Information Technology, The University of Newcastle, University Drive, Callaghan, NSW 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of Environment (CRC CARE), The University of Newcastle, PO Box 18, Callaghan, NSW 2308, Australia
| | - Ravi Naidu
- Global Centre for Environmental Research, ATC Building, Faculty of Science and Information Technology, The University of Newcastle, University Drive, Callaghan, NSW 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of Environment (CRC CARE), The University of Newcastle, PO Box 18, Callaghan, NSW 2308, Australia.
| | - Nanthi S Bolan
- Global Centre for Environmental Research, ATC Building, Faculty of Science and Information Technology, The University of Newcastle, University Drive, Callaghan, NSW 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of Environment (CRC CARE), The University of Newcastle, PO Box 18, Callaghan, NSW 2308, Australia
| | - Zhaomin Dong
- Global Centre for Environmental Research, ATC Building, Faculty of Science and Information Technology, The University of Newcastle, University Drive, Callaghan, NSW 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of Environment (CRC CARE), The University of Newcastle, PO Box 18, Callaghan, NSW 2308, Australia
| | - Yubo Yan
- Global Centre for Environmental Research, ATC Building, Faculty of Science and Information Technology, The University of Newcastle, University Drive, Callaghan, NSW 2308, Australia; Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Dane Lamb
- Global Centre for Environmental Research, ATC Building, Faculty of Science and Information Technology, The University of Newcastle, University Drive, Callaghan, NSW 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of Environment (CRC CARE), The University of Newcastle, PO Box 18, Callaghan, NSW 2308, Australia
| | - Thomas D Bucheli
- Agroscope Reckenholz-Tänikon Research Station ART, Reckenholzstrasse 191, 8046 Zürich, Switzerland
| | - Girish Choppala
- Southern Cross GeoScience, Southern Cross University, PO Box 157, Lismore 2480, NSW, Australia
| | - Luchun Duan
- Global Centre for Environmental Research, ATC Building, Faculty of Science and Information Technology, The University of Newcastle, University Drive, Callaghan, NSW 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of Environment (CRC CARE), The University of Newcastle, PO Box 18, Callaghan, NSW 2308, Australia
| | - Kirk T Semple
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, United Kingdom
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Sosa D, Hilber I, Faure R, Bartolomé N, Fonseca O, Keller A, Schwab P, Escobar A, Bucheli TD. Polycyclic aromatic hydrocarbons and polychlorinated biphenyls in soils of Mayabeque, Cuba. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:12860-12870. [PMID: 28364208 DOI: 10.1007/s11356-017-8810-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 03/13/2017] [Indexed: 05/21/2023]
Abstract
Cuba is a country in transition with a considerable potential for economic growth. Soils are recipients and integrators of chemical pollution, a frequent negative side effect of increasing industrial activities. Therefore, we established a soil monitoring network to monitor polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in soils of Mayabeque, a Cuban province southeast of Havana. Concentrations of the sum of the 16 US EPA PAHs and of the seven IRMM PCBs in soils from 39 locations ranged from 20 to 106 μg kg-1 and from 1.1 to 7.6 μg kg-1, respectively. While such concentrations can be considered as low overall, they were in several cases correlated with the distance of sampling sites to presumed major emission sources, with some of the concomitantly investigated source diagnostic PAH ratios, and with black carbon content. The presented data adds to the limited information on soil pollution in the Caribbean region and serves as a reference time point before the onset of a possible further industrial development in Cuba. It also forms the basis to set up and adapt national environmental standards.
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Affiliation(s)
- Dayana Sosa
- Centro Nacional de Sanidad Agropecuaria (CENSA), Apartado 10, CP 32700, San José de las Lajas, Mayabeque, Cuba
| | - Isabel Hilber
- Environmental Analytics, Agroscope, Reckenholzstrasse 191, 8046, Zurich, Switzerland
| | - Roberto Faure
- Centro Nacional de Sanidad Agropecuaria (CENSA), Apartado 10, CP 32700, San José de las Lajas, Mayabeque, Cuba
| | - Nora Bartolomé
- Environmental Analytics, Agroscope, Reckenholzstrasse 191, 8046, Zurich, Switzerland
- Department of Environmental System Science, ETH Zurich, 8093, Zurich, Switzerland
| | - Osvaldo Fonseca
- Centro Nacional de Sanidad Agropecuaria (CENSA), Apartado 10, CP 32700, San José de las Lajas, Mayabeque, Cuba
| | - Armin Keller
- Swiss National Soil Monitoring Network, Agroscope, Reckenholzstrasse 191, 8046, Zurich, Switzerland
| | - Peter Schwab
- Swiss National Soil Monitoring Network, Agroscope, Reckenholzstrasse 191, 8046, Zurich, Switzerland
| | - Arturo Escobar
- Centro Nacional de Sanidad Agropecuaria (CENSA), Apartado 10, CP 32700, San José de las Lajas, Mayabeque, Cuba.
| | - Thomas D Bucheli
- Environmental Analytics, Agroscope, Reckenholzstrasse 191, 8046, Zurich, Switzerland.
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10
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Zong Y, Xiao Q, Lu S. Black carbon (BC) of urban topsoil of steel industrial city (Anshan), Northeastern China: Concentration, source identification and environmental implication. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 569-570:990-996. [PMID: 27450257 DOI: 10.1016/j.scitotenv.2016.06.097] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Revised: 06/13/2016] [Accepted: 06/14/2016] [Indexed: 06/06/2023]
Abstract
Black carbon (BC) and total carbon (TC) concentrations in urban topsoils and vertical profiles from steel industrial city, Anshan, Northeastern China, were determined. A total of 115 topsoil samples and 4 soil profiles were collected, in which the BC concentrations were determined using chemical oxidation technique. The BC concentrations in urban topsoils are in the range of 1.86 to 246.46gkg(-1) with an average of 33.86gkg(-1). Both BC and TC concentrations decrease sharply with soil depth, whereas BC/TC ratio shows a little variation with depth. The spatial distribution of BC in urban topsoils reveals that the BC concentration is much higher in the northern part of the city, which is consistent with the steel production. The distribution factors (DF) of BC are the highest in 1000-500 and 500-250μm size fractions, while the lowest in 50-2μm fraction. The mass loading of BC in 250-50 and 50-2μm size fractions accounts for 76.2% of bulk soil, indicating these two size fractions responsible for BC accumulation in soils. Enrichment factor (EF) of BC in urban topsoils ranges from 0.92 to 122.01 with an average of 16.76, indicating that the urban topsoils studied are moderately or severely accumulated by the BC. Strong correlation is found between BC and pollution load index (PLI) of heavy metals, indicating the possibility of similar sources of BC and heavy metals in soils. The BC/TC ratio in soils ranges from 0.45 to 0.97, with an average of 0.75. The BC/TC ratio shows the mixed sources of BC derived from fossil fuel combustion and vehicle emissions. The BC concentration and BC/TC ratio may reflect the degree of industrial activities and pollution sources in urban soils. The study demonstrated that BC is an effective indicator of degree and "hotspots" of heavy metals pollution in urban soils.
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Affiliation(s)
- Yutong Zong
- Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition; Key Laboratory of Environmental Remediation and Ecosystem Health, Ministry of Education; College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Qing Xiao
- Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition; Key Laboratory of Environmental Remediation and Ecosystem Health, Ministry of Education; College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shenggao Lu
- Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition; Key Laboratory of Environmental Remediation and Ecosystem Health, Ministry of Education; College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
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11
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Kołtowski M, Hilber I, Bucheli TD, Oleszczuk P. Effect of activated carbon and biochars on the bioavailability of polycyclic aromatic hydrocarbons in different industrially contaminated soils. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:11058-11068. [PMID: 26906001 DOI: 10.1007/s11356-016-6196-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 01/27/2016] [Indexed: 06/05/2023]
Abstract
Coal production negatively affects the environment by the emission of polycyclic aromatic hydrocarbons (PAHs). Two soils (KOK and KB) from a coking plant area was investigated and their total PAH concentration was 40 and 17 mg/kg for the sum (∑) 16 US EPA PAHs, respectively. A third soil was sampled from a bitumen plant area and was characterized by 9 mg/kg ∑16 US EPA PAHs. To reduce the freely dissolved concentration (Cfree) of the PAHs in the soil pore water, active carbon (AC) and two biochars pyrolysed from wheat straw (biochar-S) and willow (biochar-W) were added to the soils at 0.5-5 % (w/w), each. The AC performed best and reduced the Cfree by 51-98 % already at the lowest dose. The biochars needed doses up to 2.5 % to significantly reduce the Cfree by 44-86 % in the biochar-S and by 37-68 % in the biochar-W amended soils. The high black carbon (BC) content of up to 2.3 % in the Silesian soils competed with the sorption sites of the carbon amendments and the performance of the remediation was a consequence of the contaminant's source and the distribution between the BC and the AC/biochars. In contrast, the carbon amendment could best reduce the Cfree in the Lublin soil where the BC content was normal (0.05 %). It is therefore crucial to know the contaminant's source and history of a sample/site to choose the appropriate carbon amendment not only for remediation success but also for economic reasons.
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Affiliation(s)
- Michał Kołtowski
- Department of Environmental Chemistry, Faculty of Chemistry, University of Maria Curie-Skłodowska, pl. M. Curie-Skłodowskiej 3, 20-031, Lublin, Poland
| | - Isabel Hilber
- Agroscope ISS, Reckenholzstrasse 191, 8046, Zurich, Switzerland
| | | | - Patryk Oleszczuk
- Department of Environmental Chemistry, Faculty of Chemistry, University of Maria Curie-Skłodowska, pl. M. Curie-Skłodowskiej 3, 20-031, Lublin, Poland.
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Edmondson JL, Stott I, Potter J, Lopez-Capel E, Manning DAC, Gaston KJ, Leake JR. Black Carbon Contribution to Organic Carbon Stocks in Urban Soil. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:8339-8346. [PMID: 26114917 DOI: 10.1021/acs.est.5b00313] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Soil holds 75% of the total organic carbon (TOC) stock in terrestrial ecosystems. This comprises ecosystem-derived organic carbon (OC) and black carbon (BC), a recalcitrant product of the incomplete combustion of fossil fuels and biomass. Urban topsoils are often enriched in BC from historical emissions of soot and have high TOC concentrations, but the contribution of BC to TOC throughout the urban soil profile, at a regional scale is unknown. We sampled 55 urban soil profiles across the North East of England, a region with a history of coal burning and heavy industry. Through combined elemental and thermogravimetic analyses, we found very large total soil OC stocks (31-65 kg m(-2) to 1 m), exceeding typical values reported for UK woodland soils. BC contributed 28-39% of the TOC stocks, up to 23 kg C m(-2) to 1 m, and was affected by soil texture. The proportional contribution of the BC-rich fraction to TOC increased with soil depth, and was enriched in topsoil under trees when compared to grassland. Our findings establish the importance of urban ecosystems in storing large amounts of OC in soils and that these soils also capture a large proportion of BC particulates emitted within urban areas.
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Affiliation(s)
- Jill L Edmondson
- †Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, U.K
| | - Iain Stott
- ‡Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall TR10 9FE, U.K
| | - Jonathan Potter
- †Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, U.K
| | - Elisa Lopez-Capel
- §School of Civil Engineering and Geosciences, Newcastle University, Newcastle upon Tyne NE1 7RU, U.K
| | - David A C Manning
- §School of Civil Engineering and Geosciences, Newcastle University, Newcastle upon Tyne NE1 7RU, U.K
| | - Kevin J Gaston
- ‡Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall TR10 9FE, U.K
| | - Jonathan R Leake
- †Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, U.K
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Halse AK, Schlabach M, Schuster JK, Jones KC, Steinnes E, Breivik K. Endosulfan, pentachlorobenzene and short-chain chlorinated paraffins in background soils from Western Europe. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2015; 196:21-8. [PMID: 25285612 DOI: 10.1016/j.envpol.2014.09.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 09/18/2014] [Accepted: 09/19/2014] [Indexed: 05/22/2023]
Abstract
Soils are major reservoirs for many persistent organic pollutants (POPs). In this study, "newly" regulated POPs i.e. Σendosulfans (α-endosulfan, β-endosulfan, endosulfan sulfate), pentachlorobenzene (PeCB), and short-chain chlorinated paraffins (SCCPs) were determined in background samples from woodland (WL) and grassland (GL) surface soil, collected along an existing latitudinal UK-Norway transect. Statistical analysis, complemented with plots showing the predicted equilibrium distribution and mobility potential, was then explored to discuss factors controlling their spatial distribution. SCCPs were detected with the highest average concentrations (35 ± 100 ng/g soil organic matter (SOM)), followed by Σendosulfans (3 ± 3 ng/g SOM) and PeCB (1 ± 1 ng/g SOM). PeCB and Σendosulfans share many similarities in their distribution in these background soils as well as with several legacy POPs. A steep decline in concentrations of SCCPs with increasing latitude indicates that their occurrence is dictated by proximity to source regions, while concentrations of Σendosulfans peaked in regions experiencing elevated precipitation rates.
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Affiliation(s)
- Anne Karine Halse
- NILU - Norwegian Institute for Air Research, Box 100, NO-2027 Kjeller, Norway; Norwegian University of Life Sciences, Department of Chemistry, Biotechnology and Food Science, P.O. Box 5003, NO-1432 Ås, Norway.
| | - Martin Schlabach
- NILU - Norwegian Institute for Air Research, Box 100, NO-2027 Kjeller, Norway
| | - Jasmin K Schuster
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
| | - Kevin C Jones
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
| | - Eiliv Steinnes
- Norwegian University of Science and Technology, Department of Chemistry, NO-7491 Trondheim, Norway
| | - Knut Breivik
- NILU - Norwegian Institute for Air Research, Box 100, NO-2027 Kjeller, Norway; University of Oslo, Department of Chemistry, Box 1033, NO-0315 Oslo, Norway
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Collins CD, Mosquera-Vazquez M, Gomez-Eyles JL, Mayer P, Gouliarmou V, Blum F. Is there sufficient 'sink' in current bioaccessibility determinations of organic pollutants in soils? ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2013; 181:128-132. [PMID: 23850629 DOI: 10.1016/j.envpol.2013.05.053] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 05/29/2013] [Accepted: 05/31/2013] [Indexed: 06/02/2023]
Abstract
Bioaccessibility tests can be used to improve contaminated land risk assessments. For organic pollutants a 'sink' is required within these tests to better mimic their desorption under the physiological conditions prevailing in the intestinal tract, where a steep diffusion gradient for the removal of organic pollutants from the soil matrix would exist. This is currently ignored in most PBET systems. By combining the CEPBET bioaccessibility test with an infinite sink, the removal of PAH from spiked solutions was monitored. Less than 10% of spiked PAH remained in the stomach media after 1 h, 10% by 4 h in the small intestine compartment and c.15% after 16 h in the colon. The addition of the infinite sink increased bioaccessibility estimates for field soils by a factor of 1.2-2.8, confirming its importance for robust PBET tests. TOC or BC were not the only factors controlling desorption of the PAH from the soils.
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Affiliation(s)
- C D Collins
- Soil Research Centre, University of Reading, Reading RG6 6DW, UK.
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Zhan C, Han Y, Cao J, Wei C, Zhang J, An Z. Validation and application of a thermal-optical reflectance (TOR) method for measuring black carbon in loess sediments. CHEMOSPHERE 2013; 91:1462-1470. [PMID: 23395362 DOI: 10.1016/j.chemosphere.2012.12.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2012] [Revised: 12/05/2012] [Accepted: 12/09/2012] [Indexed: 06/01/2023]
Abstract
Three techniques were used to measure black carbon (BC) in samples from Chinese loess-paleosol sequences. The results obtained by (1) chemo-thermal oxidation (CTO, performed two ways), (2) acid dichromate oxidation (Cr2O7), and (3) thermal-optical reflectance (TOR) were intercompared because prior studies have shown that the methods can yield disparate results. BC concentrations did vary among the methods, most likely because they measured different components of the BC continuum, but the high-temperature BC (soot) determined by CTO was correlated with the BC and soot obtained by TOR. The CTO and TOR methods both yielded statistically significant linear relationships for loess and lake sediments that had incremental additions of a standard (SRM-1649a). The results also showed that charred material was more abundant in these test sediments than soot carbon. Data for BC in Luochuan loess generated using TOR showed a trend similar to that of magnetic susceptibility, that is, high BC and large susceptibilities during the last interglacial and low values for both variables in the last glacial. The results thus indicate that the TOR method is well suited for studies of sedimentary materials and that more biomass burned during the last interglacial than in the last glacial.
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Affiliation(s)
- Changlin Zhan
- Key Laboratory of Aerosol Science and Technology, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710075, China
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Gogos A, Knauer K, Bucheli TD. Nanomaterials in plant protection and fertilization: current state, foreseen applications, and research priorities. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2012; 60:9781-92. [PMID: 22963545 DOI: 10.1021/jf302154y] [Citation(s) in RCA: 275] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Scientific publications and patents on nanomaterials (NM) used in plant protection or fertilizer products have exponentially increased since the millennium shift. While the United States and Germany have published the highest number of patents, Asian countries released most scientific articles. About 40% of all contributions deal with carbon-based NM, followed by titanium dioxide, silver, silica, and alumina. Nanomaterials come in many diverse forms (surprisingly often ≫100 nm), from solid doped particles to (often nonpersistent) polymer and oil-water based structures. Nanomaterials serve equally as additives (mostly for controlled release) and active constituents. Product efficiencies possibly increased by NM should be balanced against enhanced environmental NM input fluxes. The dynamic development in research and its considerable public perception are in contrast with the currently still very small number of NM-containing products on the market. Nanorisk assessment and legislation are largely in their infancies.
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Affiliation(s)
- Alexander Gogos
- Agroscope Reckenholz-Tänikon Research Station ART, 8046 Zurich, Switzerland
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Flores-Cervantes DX, Bucheli TD. Testing the resistance of fullerenes to chemothermal oxidation used to isolate soots from environmental samples. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2011; 159:3793-3796. [PMID: 21872974 DOI: 10.1016/j.envpol.2011.08.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Revised: 07/12/2011] [Accepted: 08/01/2011] [Indexed: 05/31/2023]
Abstract
We tested the resistance of five different fullerenes (C(60), C(70), C(76/78) mix, and C(84)) to chemothermal oxidation at 375 °C (CTO-375), a method that has been used and tested for quantifying black carbon (BC) and CNTs in soils and sediments. C(60) survived CTO-375 the most (50%), while C(70) was the fullerene with the lowest survival rate (<1%). Standard additions of C(60) to soil and sediment reference materials yielded recoveries between 18 and 36%. Although lower than recoveries previously observed for soot and CNTs, these results demonstrate the capability of CTO-375 to partially isolate C(60) from solid environmental matrices. Standard additions of C(70), C(76/78), and C(84) yielded slightly higher survival rates when added to soil and sediment than in their pure form. These results indicate that the mineral matrices of these samples probably had a catalytic effect towards C(60) and a protective effect towards C(70), C(76/78), and C(84) during CTO-375.
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Affiliation(s)
- D Xanat Flores-Cervantes
- Agroscope Reckenholz-Tänikon Research Station ART, Reckenholzstrasse 191, 8046 Zürich, Switzerland.
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Schuster JK, Gioia R, Moeckel C, Agarwal T, Bucheli TD, Breivik K, Steinnes E, Jones KC. Has the burden and distribution of PCBs and PBDEs changed in European background soils between 1998 and 2008? Implications for sources and processes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:7291-7. [PMID: 21819101 DOI: 10.1021/es200961p] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Background soils were collected from 70 locations on a latitudinal transect in the United Kingdom and Norway in 2008, ten years after they had first been sampled in 1998. The soils were analyzed for polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCs), to see whether there had been any change in the loadings or distributions of these persistent organic pollutants (POPs). The same transect has also been used to sample air between the mid-1990s and the present, so the air and soil spatial and temporal trends provide information on air-soil transfers, source-receptor relationships, long-range atmospheric transport (LRAT), and recycling phenomena. Comparisons of the 2008 and 1998 data sets show a general decline for PBDEs in surface soil, and a smaller averaged net decline of PCBs. Changes between the years were observed for total POP concentrations in soil and also for correlations with site and sample characteristics assumed to affect those concentrations. POP concentrations were correlated to distance and strength of possible sources, a relationship that became weaker in the 2008 data. Fractionation, a commonly discussed process for the global cycling of POPs was also lost in the 2008 data. As in 1998, soil organic matter content continues to have a strong influence on the loadings of POPs in surface soils, but changes in the PCB loads were noted. These factors indicate an approach to air-surface soil equilibrium and a lessening of the influence of primary sources on POP concentrations in soil between 1998 and 2008.
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Affiliation(s)
- Jasmin K Schuster
- Centre for Chemicals Management, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, United Kingdom.
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