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Guo J, Sharma CM, Tripathee L, Kang S, Fu X, Huang J, Shrestha KL, Chen P. Source identification of atmospheric particle-bound mercury in the Himalayan foothills through non-isotopic and isotope analyses. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 286:117317. [PMID: 33990047 DOI: 10.1016/j.envpol.2021.117317] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 04/30/2021] [Accepted: 05/03/2021] [Indexed: 06/12/2023]
Abstract
This study reports on the sources of atmospheric particle-bound mercury (HgP) in less studied regions of Nepal based on the analysis of stable mercury (Hg) isotopes in aerosol samples from two neighboring areas with high and low anthropogenic emissions (Kathmandu and Dhulikhel, respectively) during 2018. Although the Indian monsoon and westerlies are generally regarded as the primary carriers of pollutants to this region via the heavily industrialized Indo-Gangetic Plain, the concentrations of total suspended particles (TSP) and HgP in Kathmandu were higher than those in Dhulikhel, thus suggesting a substantial contribution from local sources. Both isotopic (δ200Hg and Δ199Hg) and non-isotopic evidence indicated that dust, waste burning, and industrial byproducts (without Hg amalgamation) were the major sources of Hg in Kathmandu during the study period. Mercury may have been transported via air masses from Kathmandu to Dhulikhel, as indicated by the similar organic carbon/elemental carbon ratios and seasonal trends of TSP and HgP in these two locations. Local anthropogenic sources were found to contribute significantly to atmospheric Hg pollution through dust resuspension. Therefore, dust resuspension should be considered when evaluating the long-range transport of air pollutants such as Hg, particularly in anthropogenically stressed areas.
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Affiliation(s)
- Junming Guo
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, 730000, China
| | - Chhatra Mani Sharma
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, 730000, China; Central Department of Environmental Science, Tribhuvan University, Kathmandu, Nepal
| | - Lekhendra Tripathee
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, 730000, China; Himalayan Environment Research Institute (HERI), Kathmandu, Nepal.
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, 730000, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xuewu Fu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 99 Lincheng West Road, Guiyang, 550081, China
| | - Jie Huang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese, Academy of Sciences, Beijing, 100101, China
| | - Kundan Lal Shrestha
- Department of Environmental Science and Engineering, Kathmandu University, Dhulikhel, Nepal
| | - Pengfei Chen
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, 730000, China
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Yamakawa A, Amouroux D, Tessier E, Bérail S, Fettig I, Barre JPG, Koschorreck J, Rüdel H, Donard OFX. Hg isotopic composition of one-year-old spruce shoots: Application to long-term Hg atmospheric monitoring in Germany. CHEMOSPHERE 2021; 279:130631. [PMID: 34134422 DOI: 10.1016/j.chemosphere.2021.130631] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 04/05/2021] [Accepted: 04/18/2021] [Indexed: 06/12/2023]
Abstract
The Hg isotopic composition of 1-year-old Norway spruce (Picea abies) shoots collected from Saarland cornurbation Warndt, Germany, since 1985 by the German Environmental Specimen Bank, were measured for a better understanding of the temporal trends of Hg sources. The isotopic data showed that Hg was mainly taken up as gaseous element mercury (GEM) and underwent oxidation in the spruce needles; this led to a significant decrease in the δ202Hg compared with the atmospheric Hg isotopic composition observed for deciduous leaves and epiphytic lichens. Observation of the odd mass-independent isotopic fractionation (MIF) indicated that Δ199Hg and Δ201Hg were close to but slightly lower than the actual values recorded from the atmospheric measurement of the GEM isotopic composition in non-contaminated sites in U.S. and Europe, whereas observation of the even-MIF indicated almost no differences for Δ200Hg. This confirmed that GEM is a major source of Hg accumulation in spruce shoots. Interestingly, the Hg isotopic composition in the spruce shoots did not change very significantly during the study period of >30 years, even as the Hg concentration decreased significantly. Even-MIF (Δ200Hg) and mass-dependent fractionation (MDF) (δ202Hg) of the Hg isotopes exhibited slight decrease with time, whereas odd-MIF did not show any clear trend. These results suggest a close link between the long-term evolution of GEM isotopic composition in the air and the isotopic composition of bioaccumulated Hg altered by mass-dependent fraction in the spruce shoots.
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Affiliation(s)
- Akane Yamakawa
- National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, 305-8506, Japan.
| | - David Amouroux
- Universite de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, Institut des Sciences Analytiques et de Physico-chimie pour l'Environnement et les Matériaux. Technopôle Hélioparc, 2 Avenue Pierre Angot, 64053 Pau Cedex 09, France
| | - Emmanuel Tessier
- Universite de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, Institut des Sciences Analytiques et de Physico-chimie pour l'Environnement et les Matériaux. Technopôle Hélioparc, 2 Avenue Pierre Angot, 64053 Pau Cedex 09, France
| | - Sylvain Bérail
- Universite de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, Institut des Sciences Analytiques et de Physico-chimie pour l'Environnement et les Matériaux. Technopôle Hélioparc, 2 Avenue Pierre Angot, 64053 Pau Cedex 09, France
| | - Ina Fettig
- German Environment Agency (Umweltbundesamt), Corrensplatz 1, 14195, Berlin, Germany
| | - Julien P G Barre
- Advanced Isotopic Analysis, Technopôle Hélioparc Pau Pyrénées, 2 Avenue Pierre Angot, 64053 Pau Cedex 09, France
| | - Jan Koschorreck
- German Environment Agency (Umweltbundesamt), Corrensplatz 1, 14195, Berlin, Germany
| | - Heinz Rüdel
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Auf dem Aberg 1, 57392, Schmallenberg, Germany
| | - Olivier F X Donard
- Universite de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, Institut des Sciences Analytiques et de Physico-chimie pour l'Environnement et les Matériaux. Technopôle Hélioparc, 2 Avenue Pierre Angot, 64053 Pau Cedex 09, France
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