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Pankratov AA, Nemtsova ER, Plyutinskaya AD, Vorontsova MS, Chuvilin DY, Egorova BV, Kokov KV, Deev SM, Lebedenko EN, Proshkina GM, Shul'ga AA, Golovachenko VA, Shegai PV, Kaprin AD. Specific Cytotoxicity of Targeted 177Lu and 212Pb-Based Radiopharmaceuticals. Bull Exp Biol Med 2021; 171:627-632. [PMID: 34626281 DOI: 10.1007/s10517-021-05283-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Indexed: 11/26/2022]
Abstract
Two radiopharmaceutical preparations were developed on the basis of artificial targeted polypeptide ZHER2 specific to HER2/neu tumor marker and radionuclides 177Lu (ZHER2-HSA-chelator-177Lu) or 212Pb (ZHER2-HSA-chelator-212Pb). The objective was to evaluate in vitro the cytotoxic activity of the targeted radiopharmaceuticals using two cultured human breast cancer cell lines with different expression of HER2/neu: SK-BR3 (high expression of HER2/neu) and MCF-7 (low expression of HER2/neu). It was shown that the cytotoxic effect of both preparations was significantly higher against the SK-BR-3 cells. The cytotoxicity correlated with the incubation period (it was higher after 72 h than after 24 h) and was significantly more pronounced in comparison with activity of radionuclide salts without a specific ligand. In vivo preclinical study of these pharmaceuticals seems to be very promising in animals with xenografted tumors showing high expression of HER2/neu marker.
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Affiliation(s)
- A A Pankratov
- P. A. Hertsen Moscow Oncology Research Institute - Affiliated Branch of National Medical Research Radiological Centre, Ministry of Health of the Russian Federation, Moscow, Russia
| | - E R Nemtsova
- P. A. Hertsen Moscow Oncology Research Institute - Affiliated Branch of National Medical Research Radiological Centre, Ministry of Health of the Russian Federation, Moscow, Russia.
| | - A D Plyutinskaya
- P. A. Hertsen Moscow Oncology Research Institute - Affiliated Branch of National Medical Research Radiological Centre, Ministry of Health of the Russian Federation, Moscow, Russia
| | - M S Vorontsova
- P. A. Hertsen Moscow Oncology Research Institute - Affiliated Branch of National Medical Research Radiological Centre, Ministry of Health of the Russian Federation, Moscow, Russia
| | - D Yu Chuvilin
- National Research Center Kurchatov Institute, Moscow, Russia
| | - B V Egorova
- National Research Center Kurchatov Institute, Moscow, Russia
| | - K V Kokov
- National Research Center Kurchatov Institute, Moscow, Russia
| | - S M Deev
- M. M. Shemyakin and Yu. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
- Research School of Chemistry and Applied Biomedical Sciences, National Research Tomsk Polytechnic University, Tomsk, Russia
| | - E N Lebedenko
- M. M. Shemyakin and Yu. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
- Research School of Chemistry and Applied Biomedical Sciences, National Research Tomsk Polytechnic University, Tomsk, Russia
| | - G M Proshkina
- M. M. Shemyakin and Yu. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - A A Shul'ga
- M. M. Shemyakin and Yu. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
- Research School of Chemistry and Applied Biomedical Sciences, National Research Tomsk Polytechnic University, Tomsk, Russia
| | | | - P V Shegai
- P. A. Hertsen Moscow Oncology Research Institute - Affiliated Branch of National Medical Research Radiological Centre, Ministry of Health of the Russian Federation, Moscow, Russia
| | - A D Kaprin
- P. A. Hertsen Moscow Oncology Research Institute - Affiliated Branch of National Medical Research Radiological Centre, Ministry of Health of the Russian Federation, Moscow, Russia
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2
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Kim SH, Hong GH. On the role of 210Bi in the apparent disequilibrium of 210Pb- 210Po at sea. J Environ Radioact 2019; 208-209:106024. [PMID: 31376730 DOI: 10.1016/j.jenvrad.2019.106024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 07/25/2019] [Accepted: 07/27/2019] [Indexed: 06/10/2023]
Abstract
The disequilibrium of the grandparent-daughter pair 210Pb (t1/2=22.3 years)-210Po (t1/2=138 days) has been used to estimate the export fluxes of particulate organic carbon in the ocean using particulate-matter-associated 210Po. 210Po is produced from 210Bi, not from 210Pb. The half-life of 210Bi (t1/2=5.01 days) is sufficiently long compared to the rates of biological particle formation and decomposition or dissolution occurring at sea. The role of 210Bi has not yet been assessed quantitatively in the apparent disequilibrium between 210Pb and 210Po, partly due to the non-existence of 210Bi depth profile measurements at sea up to now. However, greater affinity of 210Bi over 210Po and 210Pb was found recently in coastal waters and phytoplankton 207Bi uptake experiments. Build upon these findings, we developed a primitive and simple analytical approach to elucidate the role of 210Bi in the 210Po-210Pb pair in the ocean using a simplified two-box irreversible steady-state ocean model. We assumed that the activity concentrations in the dissolved and particulate phases of 210Pb, 210Bi, and 210Po in a given water column are solely determined by the concentration of the particles, their input and output, the distribution coefficients between dissolved and particulate phases, and decay constants of these radionuclides in the steady-state ocean. The 210Bi contribution to the 210Pb-210Po activity difference in seawater is found to be significant, therefore, it needs to be considered in estimating particle fluxes using 210Pb-210Po secular equilibrium at sea.
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Affiliation(s)
- Suk Hyun Kim
- Korea Institute of Ocean Science & Technology, Busan, 49111, Republic of Korea
| | - Gi-Hoon Hong
- Department of Geology, Wayne State University, Detroit, Detroit, MI, 48201, USA.
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Yang J, Xu J, Cheuy L, Gonzalez R, Fisher DR, Miao Y. Evaluation of a Novel Pb-203-Labeled Lactam-Cyclized Alpha-Melanocyte-Stimulating Hormone Peptide for Melanoma Targeting. Mol Pharm 2019; 16:1694-1702. [PMID: 30763112 PMCID: PMC6443429 DOI: 10.1021/acs.molpharmaceut.9b00025] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The purpose of this study is to examine the melanocortin-1 receptor (MC1R) targeting and specificity of 203Pb-DOTA-GGNle-CycMSHhex in melanoma cells and tumors to facilitate its potential therapeutic application when labeled with 212Pb. The MC1R-specific targeting and imaging properties of 203Pb-DOTA-GGNle-CycMSHhex were determined on B16/F1 and B16/F10 murine melanoma cells and in B16/F1 flank melanoma-, B16/F10 flank melanoma-, and B16/F10 pulmonary metastatic melanoma-bearing C57 mice. 203Pb-DOTA-GGNle-CycMSHhex displayed MC1R-specific binding on B16/F1 and B16/F10 melanoma cells and tumors. B16/F1 flank melanoma, B16/F10 flank melanoma, and B16/F10 pulmonary metastatic melanoma lesions could be clearly imaged by single photon emission computed tomography (SPECT) using 203Pb-DOTA-GGNle-CycMSHhex as an imaging probe. The favorable melanoma targeting and imaging properties highlighted the potential of 203Pb-DOTA-GGNle-CycMSHhex as a MC1R-targeting melanoma imaging probe and warranted the evaluation of 212Pb-DOTA-GGNle-CycMSHhex for melanoma therapy in future studies.
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Affiliation(s)
- Jianquan Yang
- Department of Radiology, University of Colorado Denver, Aurora, CO 80045, USA
| | - Jingli Xu
- Department of Radiology, University of Colorado Denver, Aurora, CO 80045, USA
| | - Lina Cheuy
- Department of Radiology, University of Colorado Denver, Aurora, CO 80045, USA
| | - Rene Gonzalez
- Department of Medical Oncology, University of Colorado Denver, Aurora, CO 80045, USA
| | - Darrell R. Fisher
- Versant Medical Physics and Radiation Safety, Richland, WA 99354, USA
| | - Yubin Miao
- Department of Radiology, University of Colorado Denver, Aurora, CO 80045, USA
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Szymańska K, Falandysz J, Skwarzec B, Strumińska-Parulska D. 210Po and 210Pb in forest mushrooms of genus Leccinum and topsoil from northern Poland and its contribution to the radiation dose. Chemosphere 2018; 213:133-140. [PMID: 30216813 DOI: 10.1016/j.chemosphere.2018.09.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 08/07/2018] [Accepted: 09/03/2018] [Indexed: 05/23/2023]
Abstract
Wild growing mushrooms are traditional food items for man and also an important source of nutrients for small and big wildlife. Nevertheless, they can be species - specifically vulnerable for contamination with heavy metals and radionuclides. We studied a less known phenomenon of accumulation of highly toxic, the alpha-radiation emitter such as 210Po and the beta emitter 210Pb by three Leccinum mushrooms: orange oak bolete L. aurantiacum (Bull.) Gray (previous name Leccinum aurantiacum var. quercinum Pilát), foxy bolete L. vulpinum Watling and slate bolete L. duriusculum (Schulzer ex Kalchbr.) Singer. Fungal and soil materials were collected from areas of a different geochemical composition in the northern regions of Poland. In parallel evaluated was the risk to human consumer due to possible intake of 210Po and 210Pb with a mushroom meal. Results showed a heterogeneous distribution of 210Po and 210Pb activity concentrations within caps and stipes of fruiting bodies. Overall activity concentration for whole dried fungi material ranged from 0.59 ± 0.38 to 3.2 ± 0.2 Bq 210Po kg-1 and from 0.45 ± 0.04 to 3.1 ± 0.2 Bq 210Pb kg-1. Evaluation showed that Leccinum mushrooms consumed by locals in typical quantity of 0.5 kg (dry biomass) can contribute into annual effective radiation dose at 0.90-3.81 μSv from 210Po decay and 0.31-2.14 μSv from 210Pb decay, which is a small portion of the annual effective radiation dose of 210Po and 210Pb for human inhabiting the northern regions of Poland.
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Affiliation(s)
- Karolina Szymańska
- Laboratory of Environmental Analytics and Radiochemistry, Environmental Chemistry and Radiochemistry Department, Faculty of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Jerzy Falandysz
- Laboratory of Environmental Chemistry and Ecotoxicology, Environmental Chemistry and Radiochemistry Department, Faculty of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Bogdan Skwarzec
- Laboratory of Environmental Analytics and Radiochemistry, Environmental Chemistry and Radiochemistry Department, Faculty of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Dagmara Strumińska-Parulska
- Laboratory of Environmental Analytics and Radiochemistry, Environmental Chemistry and Radiochemistry Department, Faculty of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland.
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Kasten BB, Oliver PG, Kim H, Fan J, Ferrone S, Zinn KR, Buchsbaum DJ. 212Pb-Labeled Antibody 225.28 Targeted to Chondroitin Sulfate Proteoglycan 4 for Triple-Negative Breast Cancer Therapy in Mouse Models. Int J Mol Sci 2018; 19:ijms19040925. [PMID: 29561763 PMCID: PMC5979285 DOI: 10.3390/ijms19040925] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Revised: 03/11/2018] [Accepted: 03/15/2018] [Indexed: 01/16/2023] Open
Abstract
Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with a poor prognosis. There is a clinical need for effective, targeted therapy strategies that destroy both differentiated TNBC cells and TNBC cancer initiating cells (CICs), as the latter are implicated in the metastasis and recurrence of TNBC. Chondroitin sulfate proteoglycan 4 (CSPG4) is overexpressed on differentiated tumor cells and CICs obtained from TNBC patient specimens, suggesting that CSPG4 may be a clinically relevant target for the imaging and therapy of TNBC. The purpose of this study was to determine whether α-particle radioimmunotherapy (RIT) targeting TNBC cells using the CSPG4-specific monoclonal antibody (mAb) 225.28 as a carrier was effective at eliminating TNBC tumors in preclinical models. To this end, mAb 225.28 labeled with 212Pb (212Pb-225.28) as a source of α-particles for RIT was used for in vitro Scatchard assays and clonogenic survival assays with human TNBC cells (SUM159 and 2LMP) grown as adherent cells or non-adherent CIC-enriched mammospheres. Immune-deficient mice bearing orthotopic SUM159 or 2LMP xenografts were injected i.v. with the targeted (225.28) or irrelevant isotype-matched control (F3-C25) mAbs, labeled with 99mTc, 125I, or 212Pb for in vivo imaging, biodistribution, or tumor growth inhibition studies. 212Pb-225.28 bound to adherent SUM159 and 2LMP cells and to CICs from SUM159 and 2LMP mammospheres with a mean affinity of 0.5 nM. Nearly ten times more binding sites per cell were present on SUM159 cells and CICs compared with 2LMP cells. 212Pb-225.28 was six to seven times more effective than 212Pb-F3-C25 at inhibiting SUM159 cell and CIC clonogenic survival (p < 0.05). Radiolabeled mAb 225.28 showed significantly higher uptake than radiolabeled mAb F3-C25 in SUM159 and 2LMP xenografts (p < 0.05), and the uptake of 212Pb-225.28 in TNBC xenografts was correlated with target epitope expression. 212Pb-225.28 caused dose-dependent growth inhibition of SUM159 xenografts; 0.30 MBq 212Pb-225.28 was significantly more effective than 0.33 MBq 212Pb-F3-C25 at inhibiting tumor growth (p < 0.01). These results suggest that CSPG4-specific 212Pb-225.28 is a useful reagent for RIT of CSPG4-expressing tumors, including metastatic TNBC.
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Affiliation(s)
- Benjamin B Kasten
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
| | - Patsy G Oliver
- Department of Radiation Oncology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
| | - Harrison Kim
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
| | - Jinda Fan
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
| | - Soldano Ferrone
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.
| | - Kurt R Zinn
- Institute for Quantitative Health Science and Engineering, Department of Radiology, Michigan State University, East Lansing, MI 48824, USA.
| | - Donald J Buchsbaum
- Department of Radiation Oncology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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Salome F, Gulson B, Chiaradia M, Davis J, Morris H. Monitoring steel bridge renovation using lead isotopic tracing. Chemosphere 2017; 174:260-267. [PMID: 28171842 DOI: 10.1016/j.chemosphere.2017.01.131] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 01/25/2017] [Accepted: 01/26/2017] [Indexed: 06/06/2023]
Abstract
Monitoring removal of lead (Pb) paint from steel structures usually involves analysis of environmental samples for total lead and determination of blood Pb levels of employees involved in the Pb paint removal. We used high precision Pb isotopic tracing for a bridge undergoing Pb paint removal to determine if Pb in the environmental and blood samples originated from the bridge paint. The paint system on the bridge consisted of an anti-corrosive red Pb primer top-coated with a Micaceous Iron Oxide (MIO) alkyd. Analysis of the red Pb primer gave uniform isotopic ratios indicative of Pb from the geologically-ancient Broken Hill mines in western New South Wales, Australia. Likewise waste abrasive material, as anticipated, had the same isotopic composition as the paint. The isotopic ratios for other samples lay on 2 separate linear arrays on a207Pb/204Pb versus 206Pb/204Pb diagram, one largely defined by gasoline and the majority of the ambient air data, and the other by data for one sample each of gasoline and ambient air and underwater sediments. Isotopic ratios in background ambient air samples for the project were characteristic of leaded gasoline. Air sampling during paint removal showed a contribution of paint Pb ranging from about 20 to 40%. Isotopic ratios in the blood of 8 employees prior to the commencement of work showed that 6 of these had been previously exposed to the Broken Hill Pb possibly from earlier bridge paint removal projects. One subject appeared to have increased exposure to Pb probably from the paint renovations.
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Affiliation(s)
- Fred Salome
- CTI Consultants Pty Ltd, Northmead, NSW 2152, Australia
| | - Brian Gulson
- Department of Environmental Sciences, Macquarie University, Sydney, NSW 2109, Australia; CSIRO Energy Flagship, North Ryde, NSW 2113, Australia.
| | - Massimo Chiaradia
- Department of Earth Sciences, University of Geneva, Rue des Maraîchers 13, 1205 Geneva, Switzerland
| | - Jeffrey Davis
- Department of Environmental Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Howard Morris
- Roads and Maritime Services (formerly RTA NSW), Australia
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7
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Anjum R, Gao J, Tang Q, He X, Zhang X, Long Y, Shi Z, Wang M. Linking sedimentary total organic carbon to 210Pb ex chronology from Changshou Lake in the Three Gorges Reservoir Region, China. Chemosphere 2017; 174:243-252. [PMID: 28171840 DOI: 10.1016/j.chemosphere.2017.01.060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 01/08/2017] [Accepted: 01/11/2017] [Indexed: 06/06/2023]
Abstract
The influences of total organic carbon (TOC) and total nitrogen (TN) on Lead-210 (210Pb) dating have recently been of increasing concern in lacustrine research. Sediment core from Changshou Lake in the Longxi catchment was investigated for influence of TOC on 210Pb dating. Lead-210 excess (210Pbex), Cesium-137 (137Cs) activities, TOC, TN, and particle size were measured. We proposed a dating index based on 137Cs chronology and particle size distribution of the lake sediment profile and rainfall erosivities calculated from Longxi catchment metrological records. Increasing trends in TOC and TN were specifically caused by commercial cage fish farming after 1989. The statistically significant correlation between 210Pbex activity, TOC (0.61, p = 0.04) and TN (0.51, p = 0.04), respectively explained post-1989 210Pb scavenging. The 210Pbex activity was closely related with coupled peaks of TOC and TN from mass depth 5-10 g cm-2. Higher TOC/TN ratio (8.33) indicated submerged macrophytes and native aquatic algal growth as main source of carbon from enhanced primary productivity because of massive fertilizer use and coherent climate warming. The study supported key hypothesis on vital role of fertilizer usage and algal derived TOC in controlling sedimentary 210Pbex activity at Changshou Lake sediment. 137Cs profile and erosive events as time markers provided reliable and consistent sedimentation rate of (1.6 cm y-1). 210Pbex activity decayed exponentially after peak at mass depth 5.68 g cm-2. Therefore, violation of 210Pb dating primary assumptions made it inappropriate for sediment dating at Changshou Lake. TOC content must be considered while using 210Pb as dating tool for lake sediment profiles.
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Affiliation(s)
- Raheel Anjum
- Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610041, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Abdul Wali Khan University, Mardan, Pakistan
| | - Jinzhang Gao
- Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610041, China
| | - Qiang Tang
- Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610041, China
| | - Xiubin He
- Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610041, China.
| | - Xinbao Zhang
- Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610041, China
| | - Yi Long
- Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610041, China
| | - Zhonglin Shi
- Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610041, China
| | - Mingfeng Wang
- Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610041, China; University of Chinese Academy of Sciences, Beijing, 100049, China
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8
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Dahmer SC, Tetreault GR, Hall RI, Munkittrick KR, McMaster ME, Servos MR. Historical decline and altered congener patterns of polychlorinated dibenzo-p-dioxins and dibenzofurans in fish and sediment in response to process changes at a pulp mill discharging into Jackfish Bay, Lake Superior. Environ Toxicol Chem 2015; 34:2489-2502. [PMID: 26468966 DOI: 10.1002/etc.3126] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Revised: 02/18/2015] [Accepted: 06/22/2015] [Indexed: 06/05/2023]
Abstract
Improved regulations for pulp and paper mill effluents and an industry shift away from elemental chlorine bleaching in the 1990s greatly reduced the release of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) into the environment. However, the high potential of these contaminants to persist in sediment and bioaccumulate in biota means that they have remained a concern. To document current contamination from bleached kraft pulp mill effluent, PCDD/Fs were measured in white sucker (Catostomus commersoni) collected from Jackfish Bay, Lake Superior. These values were contrasted to historically reported fish data as well as PCDD/F patterns from dated sediment cores. Patterns of PCDD/Fs in sediment cores from Jackfish Bay and reference sites demonstrated a relationship between contamination and mill process changes. During the peak PCDD/F contamination period (1991), when the mill was still using elemental chlorine, the contamination patterns in fish and sediment were distinct and dominated by 2,3,7,8-tetrachlorodibenzo-p-dioxin and 2,3,7,8-tetrachlorodibenzofuran. Following the reduction in the use of elemental chlorine during the early 1990s, a rapid decline was observed in PCDD/F contamination of fish tissue, and levels are now approaching background conditions with congener patterns more reflective of atmospheric sources. Although surface sediments from Jackfish Bay continue to have elevated PCDD/Fs, with some locations exceeding sediment quality guidelines, they do not appear to be highly bioavailable to benthic fish.
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Affiliation(s)
- Shari C Dahmer
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
| | - Gerald R Tetreault
- Emerging Methods Branch, Aquatic Contaminants Research Division, Water Science and Technology Directorate, Environment Canada, Burlington, Ontario, Canada
| | - Roland I Hall
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
| | - Kelly R Munkittrick
- Department of Biology, University of New Brunswick, Saint John, New Brunswick, Canada
| | - Mark E McMaster
- Emerging Methods Branch, Aquatic Contaminants Research Division, Water Science and Technology Directorate, Environment Canada, Burlington, Ontario, Canada
| | - Mark R Servos
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
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Hillyar CRT, Knight JC, Vallis KA, Cornelissen B. PET and SPECT Imaging for the Acceleration of Anti-Cancer Drug Development. Curr Drug Targets 2015; 16:582-91. [PMID: 25901527 DOI: 10.2174/1389450116666150330113747] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 01/19/2015] [Accepted: 03/16/2015] [Indexed: 11/22/2022]
Abstract
Lead-compound optimization is an iterative process in the cancer drug development pipeline, in which small molecule inhibitors or biological compounds that are selected for their ability to bind specific targets are synthesised, tested and optimised. This process can be accelerated significantly using molecular imaging with nuclear medicine techniques, which aim to monitor the biodistribution and pharmacokinetics of radiolabelled versions of compounds. Positron emission tomography (PET) and single-photon emission computed tomography (SPECT) can be used to quantify fourdimensional (temporal and spatial) clinically relevant information, to demonstrate tumor uptake of, and monitor the response to treatment with lead-compounds. This review discusses the pre-clinical and clinical value of the information provided by nuclear medicine imaging compared to the histological analysis of biopsied tissue samples. Also, the role of nuclear medicine imaging is discussed with regard to the assessment of the treatment response, radiotracer biodistribution, tumor accumulation, toxicity, and pharmacokinetic parameters, with mention of microdosing studies, pre-targeting strategies, and pharmacokinetic modelling.
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Affiliation(s)
| | | | | | - Bart Cornelissen
- CRUK/MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Off Roosevelt Drive, Oxford OX3 7LJ, UK.
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Karunakara N, Baskaran M. Special issue of Journal of Environmental Radioactivity on 2nd International Conference on Po and radioactive Pb isotopes. J Environ Radioact 2014; 138:341-342. [PMID: 25193533 DOI: 10.1016/j.jenvrad.2014.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Affiliation(s)
- N Karunakara
- Radioecology and Environmental Radioactivity Research Laboratory, Mangalore University, Mangalagangothri 574199, India.
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Al-Masri MS, Haddad K, Doubal AW, Awad I, Al-Khatib Y. Assessment of soil contamination by (210)Po and (210)Pb around heavy oil and natural gas fired power plants. J Environ Radioact 2014; 132:89-93. [PMID: 24602817 DOI: 10.1016/j.jenvrad.2014.01.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 12/05/2013] [Accepted: 01/29/2014] [Indexed: 06/03/2023]
Abstract
Soil contamination by (210)Pb and (210)Po around heavy oil and natural gas power plants has been investigated; fly and bottom ash containing enhanced levels of (210)Pb and (210)Po were found to be the main source of surface soil contamination. The results showed that (210)Pb and (210)Po in fly-ash (economizer, superheater) is highly enriched with (210)Pb and (210)Po, while bottom-ash (boiler) is depleted. The highest (210)Pb and (210)Po activity concentrations were found to be in economizer ash, whereas the lowest activity concentration was in the recirculator ash. On the other hand, (210)Pb and (210)Po activity concentrations in soil samples were found to be higher inside the plant site area than those samples collected from surrounding areas. The highest levels were found in the vicinity of Mhardeh and Tishreen power plants; both plants are operated by heavy oil and natural fuels, while the lowest values were found to be in those samples collected from Nasrieh power plant, which is only operated by one type of fuel, viz. natural gas. In addition, the levels of surface soil contamination have decreased as the distance from the power plant site center increased.
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Affiliation(s)
- M S Al-Masri
- Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus, P. O. Box 6091, Syrian Arab Republic.
| | - Kh Haddad
- Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus, P. O. Box 6091, Syrian Arab Republic
| | - A W Doubal
- Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus, P. O. Box 6091, Syrian Arab Republic
| | - I Awad
- Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus, P. O. Box 6091, Syrian Arab Republic
| | - Y Al-Khatib
- Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus, P. O. Box 6091, Syrian Arab Republic
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12
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Liu Y, Yu N, Li Z, Wei Y, Ma L, Zhao J. Sedimentary record of PAHs in the Liangtan River and its relation to socioeconomic development of Chongqing, Southwest China. Chemosphere 2012; 89:893-899. [PMID: 22664388 DOI: 10.1016/j.chemosphere.2012.05.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 05/10/2012] [Accepted: 05/11/2012] [Indexed: 06/01/2023]
Abstract
Concentrations of polycyclic aromatic hydrocarbons (PAHs) were detected in sediment cores and surface sediment samples from the Liangtan River of Chongqing, Southwest China. The total concentration of 16 PAHs ranged from 69 to 6251 ng g(-1). The spatial distribution of the PAHs reflects the intensity and scope of human activity in the catchment. A historical record of PAH contamination was reconstructed using a sediment core from a background segment of the river. The characteristic changes of concentrations, fluxes and patterns of 16 PAHs over the past ~90years were captured in detail. An obvious peak of PAH concentration and flux was found in the 1940s, i.e., during war time, and then a sharp increase was observed from the early 1980s to the present. The maximum concentration and flux reached 1260 ng g(-1) and 470 ng cm(-2)year(-1), respectively. The sharp increase was attributed to the contribution of pyrogenic sources of PAHs. The population, length of highways and energy consumption of Chongqing, as indexes of socioeconomic development, were positively correlated with PAH input in the sediment core from the 1950s to the present. The results clearly show that the local socioeconomic development in the last decades remarkably aggravated the environmental load of sedimentary PAHs.
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Affiliation(s)
- Ying Liu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, China.
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13
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Sanders CJ, Smoak JM, Cable PH, Patchineelam SR, Sanders LM. Lead-210 and Beryllium-7 fallout rates on the southeastern coast of Brazil. J Environ Radioact 2011; 102:1122-1125. [PMID: 21856052 DOI: 10.1016/j.jenvrad.2011.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 07/12/2011] [Accepted: 07/24/2011] [Indexed: 05/31/2023]
Abstract
Total ²¹⁰Pb and ⁷Be fallout rates were measured on the coastal region of Niteroi, Brazil. The monthly depositional flux of ²¹⁰Pb and ⁷Be varied by a factor of 26, from 1.7 to 43.3 mBq cm⁻² year⁻¹ and ∼27, from 7.5 to 203.5 mBq cm⁻² year⁻¹, respectively. The relatively large oscillations in the depositional flux of ²¹⁰Pb at this study site were likely due to variations in air mass sources, while the ⁷Be fluctuations may be driven by a combination of weather conditions. Local geology could support the periodic high fluxes of ²¹⁰Pb from continental air masses, as shifting oceanic wind sources were affirmed by the uncorrelated ²¹⁰Pb and ⁷Be fallout activities and ⁷Be/²¹⁰Pb ratios. The ²¹⁰Pb atmospheric deposition was found to be in agreement with local sediment inventories, an important consideration in geochemical studies that estimate sedimentation processes.
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Affiliation(s)
- Christian J Sanders
- Universidade Federal de Fluminense (UFF), Departamento de Geoquímica, Outeiro de Sao Joao Baptista s/n, Morro do Valonguinho Centro, Niterói, RJ, Brazil.
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14
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Abstract
Targeted α-particle therapy offers the potential for more specific tumor cell killing with less damage to surrounding normal tissue than β-emitters because of the combination of short path length (50-80 μm) with the high linear energy transfer (100 keV μm(-1)) of this emission. These physical properties offer the real possibility of targeted (pre-targeted) α-therapy suitable for the elimination of minimal residual or micrometastatic disease. Targeted and pre-targeted radioimmunotherapy (RIT) using α-emitters such as (212)Bi (T(1/2) = 1.01 h) and (212)Pb (T(1/2) = 10.6 h) has demonstrated significant utility in both in vitro and in vivo model systems. (212)Pb, a promising α-particle emitting source, is the longer-lived parent nuclide of (212)Bi, and serves as an in vivo generator of (212)Bi. The radionuclide has been successfully used in RIT and pre-targeted RIT and demonstrated an enhanced therapeutic efficacy in combination with chemotherapeutics, such as gemcitabine and paclitaxel. The following perspective addresses the modes of radionuclide production, radiolabelling and chelation chemistry, as well as the application of (212)Pb to targeted and pre-targeted radiation therapy.
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Affiliation(s)
- Kwon Yong
- Radioimmune & Inorganic Chemistry Section, Radiation Oncology Branch, National Cancer Institute, Building 10 Center Drive, Bethesda, Maryland, 20892-1088
| | - Martin W. Brechbiel
- Radioimmune & Inorganic Chemistry Section, Radiation Oncology Branch, National Cancer Institute, Building 10 Center Drive, Bethesda, Maryland, 20892-1088
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15
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Brown JE, Gjelsvik R, Roos P, Kålås JA, Outola I, Holm E. Levels and transfer of 210Po and 210Pb in Nordic terrestrial ecosystems. J Environ Radioact 2011; 102:430-437. [PMID: 20650552 DOI: 10.1016/j.jenvrad.2010.06.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Revised: 06/22/2010] [Accepted: 06/23/2010] [Indexed: 05/29/2023]
Abstract
Recent developments regarding environmental impact assessment methodologies for radioactivity have precipitated the need for information on levels of naturally occurring radionuclides within and transfer to wild flora and fauna. The objectives of this study were therefore to determine activity concentrations of the main dose forming radionuclides (210)Po and (210)Pb in biota from terrestrial ecosystems thus providing insight into the behaviour of these radioisotopes. Samples of soil, plants and animals were collected at Dovrefjell, Central Norway and Olkiluoto, Finland. Soil profiles from Dovrefjell exhibited an approximately exponential fall in (210)Pb activity concentrations from elevated levels in humus/surface soils to "supported" levels at depth. Activity concentrations of (210)Po in fauna (invertebrates, mammals, birds) ranged between 2 and 123 Bq kg(-1)d.w. and in plants and lichens between 20 and 138 Bq kg(-1)d.w. The results showed that soil humus is an important reservoir for (210)Po and (210)Pb and that fauna in close contact with this media may also exhibit elevated levels of (210)Po. Concentration ratios appear to have limited applicability with regards to prediction of activity concentrations of (210)Po in invertebrates and vertebrates. Biokinetic models may provide a tool to explore in a more mechanistic way the behaviour of (210)Po in this system.
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Affiliation(s)
- J E Brown
- Norwegian Radiation Protection Authority, PO Box 55, N-1332, Østerås, Norway.
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16
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Herries AIR, Shaw J. Palaeomagnetic analysis of the Sterkfontein palaeocave deposits: Implications for the age of the hominin fossils and stone tool industries. J Hum Evol 2011; 60:523-39. [PMID: 21392817 DOI: 10.1016/j.jhevol.2010.09.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2009] [Revised: 07/29/2010] [Accepted: 07/28/2010] [Indexed: 11/17/2022]
Affiliation(s)
- Andy I R Herries
- UNSW Archaeomagnetic Laboratory, Integrative Palaeoecological and Anthropological Studies, School of Medical Sciences, University of New South Wales, Kensington, Sydney 2052, Australia.
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17
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Turtiainen T, Kostiainen E, Hallikainen A. 210Pb and 210Po in Finnish cereals. J Environ Radioact 2011; 102:438-442. [PMID: 21035236 DOI: 10.1016/j.jenvrad.2010.09.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Revised: 09/13/2010] [Accepted: 09/28/2010] [Indexed: 05/30/2023]
Abstract
A survey was carried out on the activity concentrations of (210)Pb and (210)Po in cereal grains produced in Finland. The cereal species were wheat (Triticum aestivum), rye (Secale cereale), oats (Avena sativa) and barley (Hordeum vulgare), which account for 90% of the Finnish consumption of cereal products. The survey consisted of 18 flour and 13 unprocessed cereal samples and one hulled grain sample from 22 flour mills. According to the results, the mean (210)Pb/(210)Po concentrations in wheat grains, wheat flour, rye flour, oat grains and barley grains were 0.29, 0.12, 0.29, 0.36 and 0.36 Bq kg(-1), respectively. Combined with the consumption rates of the products, we assess that the mean effective doses from (210)Pb and (210)Po in cereal products for the adult male and female population are 22 and 17 μSv per year, respectively.
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Affiliation(s)
- Tuukka Turtiainen
- STUK, Radiation and Nuclear Safety Authority, P.O. Box 14, 00881 Helsinki, Finland.
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18
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MacKenzie AB, Hardie SML, Farmer JG, Eades LJ, Pulford ID. Analytical and sampling constraints in ²¹⁰Pb dating. Sci Total Environ 2011; 409:1298-1304. [PMID: 21211819 DOI: 10.1016/j.scitotenv.2010.11.040] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Revised: 11/22/2010] [Accepted: 11/29/2010] [Indexed: 05/30/2023]
Abstract
²¹⁰Pb dating provides a valuable, widely used means of establishing recent chronologies for sediments and other accumulating natural deposits. The Constant Rate of Supply (CRS) model is the most versatile and widely used method for establishing ²¹⁰Pb chronologies but, when using this model, care must be taken to account for limitations imposed by sampling and analytical factors. In particular, incompatibility of finite values for empirical data, which are constrained by detection limit and core length, with terms in the age calculation, which represent integrations to infinity, can generate erroneously old ages for deeper sections of cores. The bias in calculated ages increases with poorer limit of detection and the magnitude of the disparity increases with age. The origin and magnitude of this effect are considered below, firstly for an idealized, theoretical ²¹⁰Pb profile and secondly for a freshwater lake sediment core. A brief consideration is presented of the implications of this potential artefact for sampling and analysis.
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Affiliation(s)
- A B MacKenzie
- Scottish Universities Environmental Research Centre, Scottish Enterprise Technology Park, East Kilbride G750QF, Scotland, UK.
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19
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Narayana Y, Rajashekara KM. The importance of physico-chemical parameters on the speciation of natural radionuclides in riverine ecosystems. J Environ Radioact 2010; 101:958-964. [PMID: 20659778 DOI: 10.1016/j.jenvrad.2010.06.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2009] [Revised: 03/31/2010] [Accepted: 06/23/2010] [Indexed: 05/29/2023]
Abstract
External gamma radiation levels were measured in the catchment areas of the Sharavathi River and the dose rates in air were found to be in the range 26.0-61.0 nGy h(-1). Soil and sediment samples of the riverine environment were analysed for natural radionuclides such as (226)Ra, (232)Th and (40)K using a NaI(Tl) gamma spectrometer. The activity concentration of (210)Pb and (210)Po in soil and sediment samples was determined by radiochemical separation techniques. Evaluation of the activity concentration of radionuclides with grain size revealed an increase in the activity of (226)Ra, (232)Th and (40)K towards fine grain size. The activity concentrations for all isotopes in all samples were not significantly correlated with pH. However, the activity of (210)Po and (210)Pb in sediment showed a moderate positive correlation with organic matter content and a good correlation with clay content of sediment.
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Affiliation(s)
- Y Narayana
- Department of Studies in Physics, Mangalore University, Mangalagangotri, India.
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20
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Baldacci AE, Gattavecchia E, Kirchner G. Observations and modelling of thoron and its progeny in the soil-atmosphere-plant system. J Environ Radioact 2010; 101:992-1001. [PMID: 20727629 DOI: 10.1016/j.jenvrad.2010.07.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Revised: 07/29/2010] [Accepted: 07/29/2010] [Indexed: 05/29/2023]
Abstract
Samples of pasture vegetation, mainly Trifolium pratensis, were collected at the Botanic Garden of the University of Bologna during the period 1998-2000 and measured by gamma-spectrometry for determining thoron progeny. Concentrations of (212)Pb were between 1.5 and 20 Bq m(-2), with individual peaks up to 70 Bq m(-2). Soil samples were collected at the same location and physically characterised. Their chemical composition (particularly Th and U) was determined by X-ray fluorescence spectroscopy. Lead-212 on plants mainly originates from dry and wet deposition of this isotope generated in the lower atmosphere by the decay of its short-lived precursor (220)Rn, which is produced in the upper soil layers as a member of the natural thorium decay chain and exhales into the atmosphere. Concentrations of (220)Rn in the atmosphere depend on (1) the amount of Th present in soil, (2) the radon fraction which escapes from the soil minerals into the soil pore space, (3) its transport into the atmosphere, and (4) its redistribution within the atmosphere. The mobility of radon in soil pore space can vary by orders of magnitude depending on the soil water content, thus being the main factor for varying concentrations of (220)Rn and (212)Pb in the atmosphere. We present a simple model to predict concentrations of thoron in air and its progeny deposited from the atmosphere, which takes into account varying soil moisture contents calculated by the OPUS code. Results of this model show close agreement with our observations.
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Affiliation(s)
- A E Baldacci
- UCI-SCRM, University of Bologna, Via S. Donato 15, Bologna, Italy
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21
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Saari HK, Schmidt S, Castaing P, Blanc G, Sautour B, Masson O, Cochran JK. The particulate 7Be/210Pbxs and 234Th/210Pbxs activity ratios as tracers for tidal-to-seasonal particle dynamics in the Gironde estuary (France): implications for the budget of particle-associated contaminants. Sci Total Environ 2010; 408:4784-4794. [PMID: 20659759 DOI: 10.1016/j.scitotenv.2010.07.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Revised: 06/30/2010] [Accepted: 07/02/2010] [Indexed: 05/29/2023]
Abstract
The short-lived natural radionuclides (7)Be (T(1/2)=53 days), (234)Th(xs) (T(1/2)=24.1 days) and (210)Pb(xs) (T(1/2)=22.3 years), i.e. (234)Th and (210)Pb in excesses of that supported within particles by the decay of their parent isotopes, were analysed in suspended particulate matter (SPM) to study the particle dynamics in the Gironde fluvial estuarine system (France), strongly impacted by heavy metal pollution. From surveys of this land-ocean interface in 2006 and 2007, we established a times series of these radioisotopes and of their activity ratios ((7)Be/(210)Pb(xs) and (234)Th/(210)Pb(xs) ARs) in particles sampled under different hydrological conditions. The particulate (7)Be/(210)Pb(xs) AR varies along the fluvial estuarine system mainly due to variations in (7)Be activities, controlled by riverine, oceanic and atmospheric inputs and by resuspension of old (7)Be-deficient sediments. These processes vary with river discharge, tidal cycle and season. Therefore, seasonal particle transport processes can be described using variations of the SPM (7)Be/(210)Pb(xs) ARs. During high river discharge, the SPM (7)Be/(210)Pb(x) ARs decrease from river to the ocean. The turbidity maximum zone (TMZ) is dispersed and the particles, and the associated contaminants, are rapidly transported from river to coastal waters, without significant retention within the TMZ. During low river discharge, the TMZ intrudes into the fluvial estuary, and the lowest (7)Be/(210)Pb(x) ARs are observed there due to resuspension of (7)Be-deficient sediments. Away from the TMZ, from the middle to lower estuary, SPM (7)Be/(210)Pb(x) ARs increase, indicating that the particles have been recently tagged with (7)Be. We explain this trend as being caused by marine input of dissolved radionuclides, as traced by SPM (234)Th/(210)Pb(xs) ARs, followed by scavenging in the estuary. This result indicates that particle transport models based on (7)Be and trace-metal budgets must consider oceanic dissolved inputs as an additional source of (7)Be and, possibly, of contaminants to estuaries.
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22
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Bao K, Xia W, Lu X, Wang G. Recent atmospheric lead deposition recorded in an ombrotrophic peat bog of Great Hinggan Mountains, Northeast China, from 210Pb and 137Cs dating. J Environ Radioact 2010; 101:773-779. [PMID: 20621757 DOI: 10.1016/j.jenvrad.2010.05.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Revised: 04/23/2010] [Accepted: 05/07/2010] [Indexed: 05/29/2023]
Abstract
Radioactive markers are useful in dating lead deposition patterns from industrialization in peat archive. Peat cores were collected in an ombrotrophic peat bog in the Great Hinggan Mountains in Northeast China in September 2008 and dated using (210)Pb and (137)Cs radiometric techniques. The mosses in both cores were examined systematically for dry bulk density, water and ash content. Lead also was measured using atomic emission spectroscopy with inductively coupled plasma (ICP-AES). Both patterned peat profiles were preserved well without evident anthropogenic disturbance. Unsupported (210)Pb and (137)Cs decreased with the depth in both of the two sample cores. The (210)Pb chronologies were established using the constant rate of supply model (CRS) and are in good agreement with the (137)Cs time marker. Recent atmospheric (210)Pb flux in Great Hinggan Mountains peat bog was estimated to be 337 Bq m(-2)y(-1), which is consistent with published data for the region. Lead deposition rate in this region was also derived from these two peat cores and ranged from 24.6 to 55.8 mg m(-2)y(-1) with a range of Pb concentration of 14-262 microg g(-1). The Pb deposition patterns were consistent with increasing industrialization over the last 135-170 y, with a peak of production and coal burning in the last 50 y in Northeast China. This work presents a first estimation of atmospheric Pb deposition rate in peatlands in China and suggests an increasing trend of environmental pollution due to anthropogenic contaminants in the atmosphere. More attention should be paid to current local pollution problems, and society should take actions to seek a balance between economic development and environmental protection.
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Affiliation(s)
- K Bao
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, 3195 Weishan Road, Gaoxin District, Changchun 130012, Jilin, China
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23
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Cooke CA, Hobbs WO, Michelutti N, Wolfe AP. Reliance on (210)Pb chronology can compromise the inference of preindustrial Hg flux to lake sediments. Environ Sci Technol 2010; 44:1998-2003. [PMID: 20166657 DOI: 10.1021/es9027925] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Lake sediments are frequently used to reconstruct the rate and magnitude of human impacts on the biogeochemical cycle of mercury (Hg). The vast majority of these studies rely on excess (210)Pb inventories in short cores to temporally constrain recent trends in Hg deposition, revealing an approximately 3-fold increase in Hg deposition since preindustrial times. However, the exhaustion of unsupported (210)Pb and the onset of widespread global Hg pollution converge temporally in the late 19th century, raising the possibility that preindustrial Hg fluxes are poorly constrained. Here, we combine (210)Pb and accelerator mass spectrometry (AMS) (14)C dated lake sediment records from arctic and Andean lakes to assess the reliability of (210)Pb-derived chronologies in the estimation of preindustrial Hg fluxes. For all four studied lakes, relying on (210)Pb chronologies results in an overestimate of preindustrial Hg fluxes, because extrapolated basal (210)Pb sedimentation rates are systematically overestimated in comparison to accumulation models that include (14)C dates. In the Andes, the use of (14)C dates is critical toward assessing the full history of Hg pollution, which extends beyond the industrial era. In the Arctic, (14)C dating suggests that Hg deposition may have increased >10-fold since the Industrial Revolution, rather than the commonly quoted 3-fold increase. The incorporation of (14)C dates may therefore be necessary if accurate Hg flux histories are sought from oligotrophic lake sediments.
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Affiliation(s)
- Colin A Cooke
- Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2E3, Canada.
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Moon HB, Choi M, Choi HG, Ok G, Kannan K. Historical trends of PCDDs, PCDFs, dioxin-like PCBs and nonylphenols in dated sediment cores from a semi-enclosed bay in Korea: tracking the sources. Chemosphere 2009; 75:565-571. [PMID: 19246072 DOI: 10.1016/j.chemosphere.2009.01.064] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Revised: 01/05/2009] [Accepted: 01/24/2009] [Indexed: 05/27/2023]
Abstract
Two sediment cores, one at middle of the bay (core 1) and another at an outfall of a wastewater treatment plant (WWTP; core 2) were collected in Masan Bay, Korea, to investigate the historical records of contamination by polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), dioxin-like polychlorinated biphenyls (dl-PCBs), and nonylphenols (NPs). Vertical profiles of PCDD/Fs, dl-PCBs, and NPs in the two cores, dated using (210)Pb technique, were different but they had similar vertical profiles within the same core. The overall concentrations of these contaminants were greater in core 2 (0.05-110ng TEQkg(-1) dry wt for PCDD/Fs; 0.02-4.4ng TEQkg(-1) dry wt for dl-PCBs; 1.0-470microgkg(-1) dry wt for NPs) than in core 1 (0.72-8.0ng TEQkg(-1) dry wt for PCDD/Fs; 0.03-1.4ng TEQkg(-1) dry wt for dl-PCBs; 1.3-110microgkg(-1) dry wt for NPs). In particular, PCDD/F concentrations in core 2 were an order of magnitude greater than the concentrations in core 1. The highest concentrations of all target contaminants in cores1 and 2 were found at the surface layer (dated as 2005) and at 8-10cm ( approximately 2000), respectively. For sediment core 2, rapid changes in the concentrations and sources of target contaminants coincide with the establishment and operation of a WWTP; this suggested that discharges from WWTP contributed to contamination by PCDD/Fs, dl-PCBs and NPs in the bay. Analysis of data by non-parametric multidimensional scaling ordination showed that both the cores were influenced by different PCDD/F sources over time. Inventories and fluxes of PCDD/Fs, dl-PCBs, and NPs have rapidly increased since establishment of the WWTP, indicating that the discharge of WWTP is an important source of sediment contamination in aquatic environment.
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Affiliation(s)
- Hyo-Bang Moon
- Marine Environment Management Division, National Fisheries Research and Development Institute (NFRDI), 408-1, Sirang-ri, Gijang-eup, Gijang-gun, Busan 619-705, Republic of Korea.
| | - Minkyu Choi
- Marine Environment Management Division, National Fisheries Research and Development Institute (NFRDI), 408-1, Sirang-ri, Gijang-eup, Gijang-gun, Busan 619-705, Republic of Korea
| | - Hee-Gu Choi
- Marine Environment Management Division, National Fisheries Research and Development Institute (NFRDI), 408-1, Sirang-ri, Gijang-eup, Gijang-gun, Busan 619-705, Republic of Korea
| | - Gon Ok
- Faculty of Earth Environmental Sciences, Pukyong National University, Nam-gu, Daeyeon3-dong, 599-1, Busan 608-737, Republic of Korea
| | - Kurunthachalam Kannan
- Wadsworth Center, New York State Department of Health and Department of Environmental Health Sciences, School of Public Health, State University of New York at Albany, Empire State Plaza, P.O. Box 509, Albany, NY 12201-0509, USA
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25
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Piazza R, Ruiz-Fernández AC, Frignani M, Vecchiato M, Bellucci LG, Gambaro A, Pérez-Bernal LH, Páez-Osuna F. Historical PCB fluxes in the Mexico City Metropolitan Zone as evidenced by a sedimentary record from the Espejo de los Lirios lake. Chemosphere 2009; 75:1252-1258. [PMID: 19251301 DOI: 10.1016/j.chemosphere.2009.01.068] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2008] [Revised: 01/08/2009] [Accepted: 01/24/2009] [Indexed: 05/27/2023]
Abstract
The accumulation of PCBs over time was studied in a sediment core collected from Espejo de los Lirios, an ecological reserve located within the heart of Cuatitlan Izcalli, in the Northern part of Mexico City Metropolitan Zone. A (210)Pb-derived chronology, was used to reconstruct the historical PCB fluxes to the site during approximately 84 yr (1911-95). The highest input fluxes occurred in the 1977, after a significant increase after the late 1940s. This trend is clearly the consequence of the increasing emissions that are related to the onset of industrial activities starting from early 1970s. A phase of decrease, after the ban of the use in open systems, ended in 1989 and in 1995, at the time of sampling, the trend was toward a new increase to the highest levels. A reconstruction of PCB atmospheric concentration from sedimentary fluxes is attempted; and the estimate suggests that PCBs concentrations in the air of the Cuautitlán Izcalli seem not of concern. Nonetheless, the contamination levels found in the sediments are relatively high, reaching values above the threshold effect level (TEL) guidelines and, in two cases, close to the probable effect level (PEL) which mean that some adverse effects on the fauna may have occurred all over the time interval represented by the core.
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Affiliation(s)
- Rossano Piazza
- Dipartimento di Scienze Ambientali, Università di Venezia, Dorsoduro 2137, 30123 Venezia, Italy.
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Olid C, Garcia-Orellana J, Martínez-Cortizas A, Masqué P, Peiteado E, Sanchez-Cabeza JA. Role of surface vegetation in 210Pb-dating of peat cores. Environ Sci Technol 2008; 42:8858-8864. [PMID: 19192809 DOI: 10.1021/es801552v] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
210Pb-dated ombrotrophic peat cores have been widely used to reconstructthe atmospheric fluxes of heavy metals forthe past century. Many of these studies rarely include the overlying vegetation compartment (i.e., the aerial part of vegetation and decayed plant remains) in the analysis although it represents the first layer capturing atmospheric deposition. The aim of this study was to evaluate the radionuclide and Pb content of this biologically active layer in bogs and to assess its implications on the total inventories and the 210Pb-derived chronology. We analyzed two short ombrotrophic peat cores from the same bog (Chao de Lamoso, Galicia, Spain) for 210Pb, artificial radionuclides (137Cs and 241Am), and Pb. The total Pb inventory was underestimated by about 12% when the plant material was not included in the record. The atmospheric origin of 210Pb and the uptake of 137Cs by roots led to significant activities of these radionuclides in the upper layers. Therefore, removing them from the peat record would imply even larger underestimations of the total inventories, ranging from 25% to 36% for 137Cs and from 39% to 49% for 210Pb. In contrast to the chronologies inferred from the constant rate of supply (CRS) model when only peat layers are considered, the 210Pb chronology agreed well with artificial radionuclide dating when surface vegetation was included. These results suggest that an accurate peat chronology requires an initial evaluation of the relevance of plant inventories and emphasizes the need of considering the biologically active layer when atmospheric fluxes of heavy metals and other pollutants are reconstructed.
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Affiliation(s)
- Carolina Olid
- Departament de Fisica and Institut de CiBncia i Tecnologia Ambientals, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Spain.
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Arndt MF, West LE. An experimental analysis of the contribution of 210Po and of 210Po produced by 210Pb decay to the gross alpha-particle activity of water samples. Health Phys 2008; 95:310-316. [PMID: 18695412 DOI: 10.1097/01.hp.0000315807.81067.04] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The contribution of 210Po and of 210Po produced by 210Pb decay to the gross alpha-particle activity of water samples by U.S. Environmental Protection Agency Method 900.0 is investigated as a function of residue mass and geometry and time between sample collection and analysis. It is shown that these factors can cause the contribution to gross alpha-particle activity of 210Po to be up to 2.0 and 1.1 times the initial 210Po activity for grab and quarterly composite samples, respectively, and can cause the contribution to gross alpha-particle activity of 210Po from 210Pb decay to be up to 1.1 times and 1.5 times the 210Pb activity for grab and quarterly composite samples, respectively. It is also shown qualitatively that at least for some residues, there is a loss of polonium due to volatilization when the sample is heated over a flame.
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Affiliation(s)
- Michael F Arndt
- Environmental Health Division, Wisconsin State Laboratory of Hygiene, 2601 Agriculture Drive, Madison, WI 53718, USA.
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Guevara SR, Arribére M. Comment on the article 'Radionuclide dating (Pb-210, Cs-137, Am-241) of recent lake sediments in a highly active geodynamic setting (Lakes Puyehue and Icalma-Chilean Lake District)'. Sci Total Environ 2007; 385:310-1; discussion 12-4. [PMID: 17555798 DOI: 10.1016/j.scitotenv.2007.05.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Accepted: 05/04/2007] [Indexed: 05/15/2023]
Abstract
The correlation of Cs-137 specific activity profiles with the historical fallout sequence in the study region is essential in sediment cores dating using this technique. The authors of the referenced article considered 1965 the end of Cs-137 fallout in the study region, omitting the South Pacific nuclear test from 1966 to 1974, proved that generated the most intense Cs-137 fallout.
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Affiliation(s)
- Sergio Ribeiro Guevara
- Laboratorio de Análisis por Activatión Neutrónica, Centro Atómico Bariloche, 8400 Bariloche, Argentina
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29
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Burnett A, Kurtz AC, Brabander D, Shailer M. Dendrochemical record of historical lead contamination sources, Wells G&H Superfund site, Woburn, Massachusetts. J Environ Qual 2007; 36:1488-94. [PMID: 17766828 DOI: 10.2134/jeq2006.0367] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Laser-ablation inductively coupled-plasma mass-spectrometry analysis of red oak (Quercus rubra) from a well documented heavy metal contaminated United States Environmental Protection Agency superfund site in Woburn, Massachusetts reveals decade-long trends in Pb contaminant sources. Lead isotope ratios (207Pb/206Pb and 208Pb/206Pb) in tree rings plot along a linear trend bracketed by several local and regional contamination sources. Statistically significant interannual variations in 207Pb/206Pb suggest that atmospheric Pb is rapidly incorporated into wood, with minimal mobility subsequent to deposition in annual growth rings. We interpret the decadal trends in our record as a changing mixture of local pollution sources and gasoline-derived Pb. Between 1940 and 1970, Pb was predominantly derived from remobilization of local industrial Pb sources. An abrupt shift in 207Pb/206Pb may indicate that local Pb sources were overwhelmed by gasoline-derived Pb during the peak of leaded gasoline emissions in the late 1960s and early 1970s.
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Affiliation(s)
- Aaron Burnett
- Department of Earth Sciences, Boston University, Boston, MA 02215, USA
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Di Gregorio DE, Fernández Niello JO, Huck H, Somacal H, Curutchet G. 210Pb dating of sediments in a heavily contaminated drainage channel to the La Plata estuary in Buenos Aires, Argentina. Appl Radiat Isot 2007; 65:126-30. [PMID: 16934477 DOI: 10.1016/j.apradiso.2006.06.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2006] [Revised: 06/29/2006] [Accepted: 06/29/2006] [Indexed: 10/24/2022]
Abstract
Concentrations of (210)Pb and (137)Cs in sediment samples collected from two cores at a drainage channel to the La Plata river estuary in Buenos Aires, Argentina, were measured using ultralow-background detection systems. The (210)Pb data were used to determine the rate of sediment accumulation of the sites. These results were correlated with some heavy metal (chromium and lead) concentrations of the samples in an attempt to characterize the historical input of contaminants due to the industrial development, which has taken place in this area over the last century. The (137)Cs measurements demonstrate that cesium dating is not adequate in regions of the southern hemisphere.
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Affiliation(s)
- D E Di Gregorio
- Departamento de Física, Comisión Nacional de Energía Atómica, Av. Gral. Paz 1499, 1650 San Martín, Provincia de Buenos Aires, Argentina.
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31
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Abstract
The compaction effect may significantly flatten an excess (210)Pb depth profile near the sediment-water interface, resulting in erroneous (210)Pb dating. There are three mathematical approaches to correct for the compaction effect. In the present paper, some further deductions have been done to make the procedure of approach calculations more clearly and practically. Meanwhile, the three approaches are also compared using a case study selected from the literature.
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Affiliation(s)
- Xueqiang Lu
- Graduate School of Environmental Studies, Nagoya University, Nagoya 464 8601, Japan.
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Abstract
A new method has been developed for determination of (210)Pb and (210)Po in soil or rock samples containing refractory matrices. The samples were first fused with Na(2)CO(3) and Na(2)O(2) at 600 degrees C for pre-treatment and then (210)Pb and (210)Po were sequentially leached out at 200-250 degrees C with HNO(3)+HF, HClO(4) and HCl. About 10% of the leaching solution was used for (210)Po determination, carried out by spontaneous deposition of polonium on a silver disc from a weakly acidic solution that contained hydroxylamine hydrochloride, sodium citrate and (209)Po tracer, measurement being made by alpha-spectrometry. The remains of the leaching solution were used for determination of (210)Pb, conducted by precipitation as sulphate, purification with Na(2)S as PbS in 6M ammonium acetate, separation from alpha-emitters by an anion-exchange resin column, source preparation as PbSO(4), and measurement with a beta-counter. The procedure has been checked with two certified IAEA reference materials, showing good agreement with the recommended values. The lower limits of detection for 1g of analysed soil or rock samples were found to be 0.75 Bqkg(-1) for (210)Po and 2.2 Bqkg(-1) for (210)Pb. A variety of solid sample species analysed through use of the procedure gave average yields of 90.0+/-9.8% for (210)Po and 88.4+/-7.1% for (210)Pb.
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Affiliation(s)
- Guogang Jia
- Agency for Environmental Protection and for Technical Services, Via V. Brancati 48, 00144 Roma, Italy.
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Abstract
The fraction of the positively charged unattached radon decay products, 218Po and 214Pb in indoor air was determined by model calculations. The results of the calculations were confirmed by measurements in a test chamber (volume: 8 m3). The fraction of both radionuclides depends on the attachment parameter (S(1)) and the neutralisation rate (nu) in room air. The total removal parameter S1 = lambda1 + v + q(f) + X = lambda1 C1f/C0 considers the attachment rate to aerosol particles (X), plate-out rate to room surfaces (q(f)) and the ventilation rate (nu) (lambda1: decay constant of 218Po). The S1-value of room can be determined by measurement of the concentration of the unattached 218Po clusters (C1f) and radon (C0). The neutralisation rate (nu) in environmental air depends mainly on the ion production rate. The influence of the relative humidity in the range 30-95% (temperature: 20 degrees C) is negligible. In addition, equal neutralisation rates for 218Po and 214Pb could be derived. In room air with ion production rates between 5 and 500 nC kg(-1) h(-1) mainly generated by the alpha emitters of radon, thoron and their short-lived decay products, the fractions for positive 218Po clusters vary between 55 and 17% and for 214Pb clusters between 53 and 14%. For a typical average concentration of radon (50 Bq m(-3)) and thoron (10 Bq m(-3)) in homes, 48% of 218Po clusters and 45% of 214Pb clusters are positively charged.
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Affiliation(s)
- J Porstendörfer
- Institute of Physical Chemistry, Georg-August-University Göttingen, Tammannstrasse 6, D-37077 Göttingen, Germany
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McCubbin D, Leonard KS, Young AK, Maher BA, Bennett S. Application of a magnetic extraction technique to assess radionuclide-mineral association in Cumbrian shoreline sediments. J Environ Radioact 2004; 77:111-131. [PMID: 15312698 DOI: 10.1016/j.jenvrad.2004.02.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2003] [Revised: 02/09/2004] [Accepted: 02/20/2004] [Indexed: 05/24/2023]
Abstract
An assessment has been made of the association of (239+240)Pu, 241Am and 210Po (in secular equilibrium with 210Pb) with iron minerals using a magnetic extraction technique. Grab samples of beach sand from the Cumbrian (UK) coastline were subjected to successive extractions with an approximately 0.1 T ferrite magnet and an approximately 0.3 T rare-earth magnet procedure to separate magnetic iron oxide minerals. Radionuclide concentrations in the magnetic extracts were enhanced (by approximately 4-6-fold) relative to the residue. Those in the approximately 0.1 T magnet extracts were broadly similar to those in the antiferromagnetic material extracted by the approximately 0.3 T magnet, despite the very large differences in magnetic property values between the two fractions (one to two orders of magnitude). The percentage of magnetic material in terms of mass was small and therefore, the majority of these radionuclides (on average 88%) were associated with the residue. Removal of stable Fe was incomplete. Given that the radionuclides may also bind to paramagnetic (nonmagnetic) Fe minerals, the data were extrapolated by normalising the results to quantitative Fe removal. This yielded average values of 37%, 45% and 46% for (239+240)Pu, 241Am and 210Po(210Pb), respectively, as upper limits for the fraction associated with magnetic + nonmagnetic Fe minerals. There are significant uncertainties inherent in quantifying data from this extraction technique. Nevertheless, it seems reasonable to conclude that radionuclide association with Fe minerals is unlikely to have a significant impact upon the physical dispersion of sediment contaminated by Sellafield discharges in the Irish Sea. However, it may be an important factor in governing Pu redox and redissolution behaviour.
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Affiliation(s)
- David McCubbin
- Lowestoft Laboratory, The Centre for Environment, Fisheries and Aquaculture Science (CEFAS), Pakefield Road, Lowestoft, Suffolk NR33 OHT, UK.
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Ahmed AA, Mohamed A, Ali AE, Barakat A, Abd El-Hady M, El-Hussein A. Seasonal variations of aerosol residence time in the lower atmospheric boundary layer. J Environ Radioact 2004; 77:275-283. [PMID: 15381321 DOI: 10.1016/j.jenvrad.2004.03.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/16/2004] [Indexed: 05/24/2023]
Abstract
During a one year period, from Jan. 2002 up to Dec. 2002, approximately 130 air samples were analyzed to determine the atmospheric air activity concentrations of short- and long-lived (222Rn) decay products 214Pb and 210Pb. The samples were taken by using a single-filter technique and gamma-spectrometry was applied to determine the activity concentrations. A seasonal fluctuation in the concentration of 214Pb and 210Pb in surface air was observed. The activity concentrations of both radionuclides were observed to be relatively higher during the winter/autumn season than in spring/summer season. The mean activity concentration of 214Pb and 210Pb within the whole year was found to be 1.4+/-0.27 Bq m(-3) and 1.2+/-0.15 mBq m(-3), respectively. Different 210Pb:214Pb activity ratios during the year varied between 1.78 x 10(-4) and 1.6 x 10(-3) with a mean value of 8.9 x 10(-4) +/- 7.6 x 10(-5). From the ratio between the activity concentrations of the radon decay products 214Pb and 210Pb a mean residence time (MRT) of aerosol particles in the atmosphere of about 10.5+/-0.91 d could be estimated. The seasonal variation pattern shows relatively higher values of MRT in spring/summer season than in winter/autumn season. The MRT data together with relative humidity (RH), air temperature (T) and wind speed (WS), were used for a comprehensive regression analysis of its seasonal variation in the atmospheric air.
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Affiliation(s)
- A A Ahmed
- Physics Department, Faculty of Science, El-Minia University, El-Minia, Egypt
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36
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Wallner G, Berner A, Irlweck K. Aerosols: unexpected disequilibrium phenomena between airborne radio activities of lead-210 and its progenies bismuth-210 and polonium-210. Naturwissenschaften 2002; 89:569-74. [PMID: 12536280 DOI: 10.1007/s00114-002-0374-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2002] [Accepted: 10/05/2002] [Indexed: 10/25/2022]
Abstract
For the first time, concentrations of the long lived radon progenies (210)Pb, (210)Bi and (210)Po were measured in the mine atmosphere of the so called "healing gallery" in Badgastein, Austria, a region famous for its radioactive springs. These investigations were performed in order to study the radioactive equilibrium between the (210)Pb-(210)Bi and the (210)Pb-(210)Po pairs so as to gain more information about the aerosol-forming processes in the mine. The particle size distribution of the aerosols was determined under different ventilation conditions. Six-stage and eight-stage cascade impactors with working ranges from 0.15 to 5 micro m and from 0.063 to 8 micro m, respectively, were used to collect the mine aerosols. These samples were analysed in the laboratory and measured by liquid scintillation spectrometry. The most surprising results were found under full ventilation, when the total activity concentrations of (210)Pb, (210)Bi and (210)Po were 4.6, 2.0 and 16.5 mBq/m(3), respectively. In this case (210)Po/(210)Pb activity ratios ranged between 1.8+/-0.3 and 4.3+/-0.3. These unexpected results were confirmed by the eight-stage impactor samples. For the smallest particles, between 0.062 and 0.125 micro m, an even higher value of 7.5 was observed. As outside sources could be excluded, such (210)Po enrichments must occur during the aerosol-forming process itself inside the mine.
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Affiliation(s)
- Gabriele Wallner
- Institute for Inorganic Chemistry, University of Vienna, Währingerstrasse 42, 1090 Vienna, Austria.
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Abstract
The impact of loading cargoes of phosphate ore into ships on the near marine environment at the Syrian coast has been evaluated. Results have shown a significant enhancement of 210Po, 210Pb and other natural radionuclides in sediment and surface water inside the port area. The highest 210Po and 210Pb concentrations observed in sediment were found to be 170 and 64 Bq kg(-1) respectively, while 210Pb and 210Po concentrations in surface water ranged from 5 to 20 mBq l(-1) and 0.93 to 3.23 mBq l(-1). In addition, comparable values of 210Po and 210Pb for all marine organisms (algae, crab and fish) suggest that their use as indicators for phosphate pollution is not recommended. However, the effect of loading cargoes on the port marine environment of Tartous was found to be mainly related to wind direction where radioactive air particulate are either being dispersed to land or sea.
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Affiliation(s)
- M S Al-Masri
- Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus
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38
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San Miguel EG, Bolívar JP, García-Tenorio R, Martín JE. 230Th/232Th activity ratios as a chronological marker complementing 210Pb dating in an estuarine system affected by industrial releases. Environ Pollut 2001; 112:361-368. [PMID: 11291442 DOI: 10.1016/s0269-7491(00)00146-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The main purpose of this research is to show the usefulness of the 230Th/232Th activity ratios as a chronological marker that can be helpful in the dating of sediment cores collected from an estuarine system located in the south west of Spain highly polluted by wastes from fertilizer plants. These wastes, being released for 30 years, and enriched in radionuclides from the uranium series including 210Pb, invalidate the application of the 210Pb dating technique in full extent to the sediment cores collected in this estuary. However, the evaluation and the interpretation of both 210Pb and 230Th/232Th profiles allows the determination of average sedimentation rates in different parts of the cores, contaminated and noncontaminated zone, that agree in the case analysed in this research. Through this approach, a confident chronology covering the last century, which is essential to analyse and reconstruct the historical evolution of other pollutants in this heavily contaminated system can be established.
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Affiliation(s)
- E G San Miguel
- Departamento de Física Aplicada, EPS La Rábida, 21819-Palos, Huelva, Spain.
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Dadachova E, Chappell LL, Brechbiel MW. Spectrophotometric method for determination of bifunctional macrocyclic ligands in macrocyclic ligand-protein conjugates. Nucl Med Biol 1999; 26:977-82. [PMID: 10708314 DOI: 10.1016/s0969-8051(99)00054-2] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A simple spectrophotometric assay for determination of bifunctional polyazacarboxylate-macrocyclic ligands of different sizes that are conjugated to proteins has been developed for: 12-membered macrocycle DOTA (2-[4-nitrobenzyl]-1, 4, 7, 10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid) and analogs, the 15-membered PEPA macrocycle (2-[4-nitrobenzyl]-1,4,7,10,13-pentaazacyclopentadecane-N,N',N'',N ''',N''''-pentaacetic acid), and the large 18-membered macrocycle HEHA (1,4,7,10,13,16-hexaazacyclooctadecane-N,N',N'',N''',N'''',N'''''- hexaacetic acid). The method is based on titration of the blue-colored 1:1 Pb(II)-Arsenazo II (AAIII) complex with the polyazacarboxylate macrocyclic ligand in the concentration range of 0-2.5 microM, wherein color change occurring upon transchelation of the Pb(II) from the AAIII to the polyazamacrocyclic ligand is monitored at 656 nm. The assay is performed at ambient temperature within 20 min without any interfering interaction between the protein and Pb(II)-AA(III) complex. Thus, this method also provides a ligand-to-protein ratio (L/P ratio) that reflects the effective number of ligands per protein molecule available to radiolabeling. The method is not suitable for 14-membered TETA macrocycle (2-[4-nitrobenzyl]-1, 4, 8, 11-tetraazacyclotetradecane N,N',N'',N'''-tetraacetic acid) because of low stability constant of Pb(II)-TETA complex. The method is rapid, simple and may be customized for other polyazacarboxylate macrocyclic ligands.
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Affiliation(s)
- E Dadachova
- Radioimmune and Inorganic Chemistry Section, Radiation Oncology Branch, National Cancer Institute, NIH, Bethesda, Maryland 20892, USA.
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Abstract
Lead stable isotope ratio (IR) analysis by inductively coupled plasma mass spectrometry was used to examine the relationship between sources of Pb in 22 dust wipe samples collected from 10 homes in Jersey City, NJ. Common lead sources examined included interior lead-based paints, exterior soils and street dusts, and indoor air. High correlations between IRs of wipe samples and both street dusts and exterior soils indicated these two exterior sources were indistinguishable. They were treated as a single exterior source in a source apportionment using IR matching and a simple mixing model. The upper-bound estimate of the contribution of interior lead-based paints to 10 floor- and eight sill-wipe samples was 56% and 50%, respectively. It was not possible to apportion sources in four of the 22 samples because wipe sample IRs were outside the range of measured sources. Examination of means obscures the variability in the data, however, as eight of the 18 apportioned samples matched interior or exterior source media. In most cases, however, sources from outside the home contribute as much Pb to house dust wipe samples as interior lead-based paints.
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Affiliation(s)
- J L Adgate
- Environmental and Occupational Health Sciences Institute (EOHSI), Piscataway, NJ 08855-1179, USA.
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Lever SZ, Stricklin DL. Preparation of radioactive lead complexes utilizing Chelex methodology. Nucl Med Biol 1996; 23:1013-7. [PMID: 9004291 DOI: 10.1016/s0969-8051(96)00156-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The use of Chelex resin for the synthesis of radioactive lead complexes has been explored. The process involved immobilization of 203Pb on the resin and subsequent elution of complexed lead by chelating agents. 203Pb complexes derived from meso- and racemic dimercaptosuccinic acid (meso-DMSA, rac-DMSA) were prepared and assessed for stability in vitro.
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Affiliation(s)
- S Z Lever
- Department of Environmental Health Sciences, Johns Hopkins University School of Hygiene and Public Health, Baltimore, MD 21205-2179, USA
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