Chemical Speciation and Characterization of Trace Metals in Dry Camellia sinensis and Herbal Tea Marketed in Nigeria

Background. Trace metals from anthropogenic activities have been found to occur in tea brands and pose potential human health risks to consumers. Objectives. The present study assessed the concentrations of trace metals in green, black and herbal tea brands using a modified Community Bureau of Reference sequential extraction method. Methods. Fifteen (15) Camellia sinensis and eight (8) herbal tea samples commonly consumed in Nigeria were collected and analyzed for trace metals. The concentrations of cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), vanadium (V), and zinc (Zn) in extract fractions were analyzed using microwave plasma atomic emission spectroscopy (MP-AES). Results. Trace metals were detected in all of the samples investigated. The concentrations of trace metals in 4 stages (soluble/exchangeable/carbonates bound fraction, reducible fraction, oxidizable fraction, residual fraction) of sequential and pseudo-total metal extraction procedures are presented. The concentrations of Cd, Cr, Cu, Mn, Ni, Pb, V, and Zn in the exchangeable/carbonate bound fraction for green tea ranged between 0.27–1.47, ND-0.33, ND-0.44, 7.05–33.04, 0.23–0.69, ND-0.51, ND-0.16 and 0.18–1.99 mg/kg, ND-0.73, 0.15–0.36, 0.36–0.59, 1.38–30.07, 0.15–0.54, 0.05–0.76, 0.15–0.34 and 0.27–0.77 mg/kg and 0.54–0.64, 0.25–0.41, 0.35–0.47, 18.72–23.98, 0.30–0.55, 0.15–0.21, 0.15–0.23 and 0.30–0.48 mg/kg for hebal tea, respectively. Conclusion. The metal content in the investigated tea indicated low to enhanced concentrations. Locally produced black teas recorded relatively low trace metal contents compared to the green and herbal tea samples. The most bioavailable trace metal was Mn, while Zn was most preferably bound to the residual fraction. Cadmium, Cr, Cu, Ni, Pb, and V were distributed at varied concentrations among other extractable phases. Daily consumption of the investigated tea products may expose consumers to potentially toxic metals as well as essential elements. Competing interests. The authors declare no competing financial interests.

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Trace metal speciation in the Yamaska and St. François Rivers (Quebec)

Canadian Journal of Earth Sciences ◽

10.1139/e80-008 ◽

1980 ◽

Vol 17 (1) ◽

pp. 90-105 ◽

Cited By ~ 155

Author(s):

A. Tessier ◽

P. G. C. Campbell ◽

M. Bisson

Keyword(s):

Organic Matter ◽

Trace Metals ◽

Trace Metal ◽

Suspended Sediment ◽

Extraction Procedure ◽

Municipal Sewage ◽

Residual Fraction ◽

Metal Concentrations ◽

Sediment Samples ◽

Mn Oxides

Water and suspended sediment samples were collected at 12 stations on the Yamaska and St. François Rivers, located in southeastern Quebec, and were analyzed for the trace metals Cd, Co, Cu, Ni, Pb, Zn, Fe, and Mn. The suspended sediment samples were subjected to a sequential extraction procedure designed to partition the particulate trace metals into five fractions: (1) exchangeable; (2) bound to carbonates; (3) bound to Fe–Mn oxides; (4) bound to organic matter; and (5) residual.Although suspended sediment levels as well as total soluble and particulate trace metal concentrations were highly variable in time and space, speciation patterns for each metal proved reasonably constant. Very small proportions of all metals, except Cd and Mn, were found in the exchangeable fraction, whereas high levels of all metals were present in the residual fraction; Fe–Mn oxides and organic matter constituted important transport phases for most metals. Deviations from this general behaviour were occasioned by man-induced perturbations (e.g., inputs of municipal sewage or mine waste water). At stations influenced by such factors, total particulate metal concentrations increased and the relative contribution of the residual fraction decreased. The trace metal content of fraction 3 proved to be particularly sensitive to anthropogenic inputs; other phases acting as trace metal sinks included those liberated in fractions 1 (Cd, Cu, Ni, Zn), 2(Cu, Ni, Zn), and 4(Cu, Ni).

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A case study investigating the effects of EDTA washing and amendments on trace metal-contaminated soil

10.5194/egusphere-egu2020-3488 ◽

2020 ◽

Author(s):

Wolfgang Friesl-Hanl ◽

Christoph Sebastian Noller ◽

Rebecca Hood-Nowotny ◽

Andrea Watzinger

Keyword(s):

Trace Metals ◽

Trace Metal ◽

Soil Washing ◽

Ex Situ ◽

Metal Extraction ◽

Garden Soil ◽

Soil Conditions ◽

Industrial Emissions ◽

Guideline Values

Trace metals emissions show a sustaining decrease in western Europe since several decades. Sources like leaded fuels have been banned and the use of efficient flue gas cleaning systems have reduced industrial emissions significantly. But trace metal additions are cumulative, and the contamination is permanent. Immobilizing trace metals can be an efficient and cost effective way to prevent groundwater contamination and uptake in the food chain but cannot account for all exposure pathways (e.g. ingestion), while guideline values are only concerned about total concentrations. Soil washing techniques comprise an enormous potential for the efficient and sustainable extraction of trace metals from contaminated soils. The Garden Soil Project is a case study investigating the effect of soil amendments applied after a new ex-situ soil washing procedure (Ethylenediaminetetraacetic acid) from a Cd-, Pb-, Zn-contaminated Cambisol from Arnoldstein, located at a former lead mining and smelting region in Austria.To investigate the success of the EDTA soil washing and amendment application, an experimental garden was set up at the University Research Center (UFT) in Tulln an der Donau. It encompasses twelve raised beds of 1 m3, filled with three soil variants in four replicates: The contaminated, unwashed soil (U) and two washed variants (W), one amended with 2 %wt biochar and 2 %wt compost (A). The amendments aim to restore soil conditions after the invasive procedure. The success of the trace metal extraction and restoration of the original soil properties is investigated by analyzing vegetable cultivars grown on the soil variants, the physicochemical and microbiological characteristics of the soil in the course of 2 years. First results show a significant reduction in trace metal uptake by different vegetables after washing and an increase in biomass for both washed soil variants W and A. The continuing analysis of trace metals in soil leachates and multiple extractable fractions in soil will allow a more detailed assessment. Furthermore, an ongoing investigation of the carbon and nitrogen cycle, using stable isotopes, will be applied as an indicator for soil functions.

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Using Modified Tessier Scheme to Metal Speciation in a Former Sewage Farm and interpretation of the sequential extraction by FTIR

10.5194/egusphere-egu21-6482 ◽

2021 ◽

Author(s):

Shaghayegh Ramezany ◽

Magdalena Sut-Lohmann ◽

Friederike Klos ◽

Alexander Bonhage ◽

Thomas Raab

Keyword(s):

Organic Matter ◽

Sequential Extraction ◽

Toxic Metals ◽

Agricultural Land ◽

Metal Speciation ◽

Metal Extraction ◽

Residual Fraction ◽

Potentially Toxic Metals ◽

Sewage Farm ◽

Mn Oxides

We present a study conducted on a former sewage farm near Berlin, where long term sewage disposal onto agricultural land resulted in a high accumulation of potentially toxic metals. Based on a previous study, 30 samples collected within an area of a former sedimentation basin were selected (at the depth of 15-20 cm and one borehole up to 100 cm deep). The modified Tessier sequential extraction was applied in order to determine the partitioning of particulate potentially toxic metals (Cr, Cu, Ni, Pb, and Zn) into following fractions: 1) Exchangeable, 2) Bound to carbonate, 3) Bound to Fe/Mn oxides, 4) Bound to organic matter, and 5) Residual fraction. As a complementary analysis, diffuse reflectance infrared fourier transform spectroscopy (DRIFTS) technique was used for the interpretation purposes.The obtained results demonstrated different metal speciation in the studied soil; Pb was mostly discovered in the residual fraction (77%) followed by Cr (53%), Cu (8%), and Zn (5%), while Ni was not extracted in this fraction. The organic matter-bound is the dominant species of Cu (77%). However, Zn and Ni exhibit the highest affinity for Fe/Mn oxides fraction (55% and 39%, respectively). The average mobility factor followed the order Ni > Zn > Cu whereas Cr and Pb were not found as exchangeable nor in carbonate forms. Study also revealed that DRIFTS is applicable to interpret the sequential metal extraction, especially for the carbonates-bound, organic matter-bound, and residual fractions. The spectral changes in organic and inorganic regions can indicate the soil components&#8217; dissociation is proportional to the extraction.

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Bioaccumulated trace metal profiles of Tympanotonus fuscatus, Periophthalmus barbarous and Guinearma (Sesarma) alberti collected from a perturbed freshwater mangrove swamp in Warri, Nigeria

Journal of Applied Sciences and Environmental Management ◽

10.4314/jasem.v25i3.20 ◽

2021 ◽

Vol 25 (3) ◽

pp. 439-444

Author(s):

O. Odigie ◽

J.O. Olomukoro

Keyword(s):

Trace Metals ◽

Trace Metal ◽

Anthropogenic Activities ◽

West African ◽

Ecological Effects ◽

Wetland Area ◽

Mangrove Swamp ◽

Affected Area ◽

The Mean ◽

Different Levels

Bio –concentrated levels of trace metals; Fe, Zn, Cu, Cd and Pb in three (3) freshwater mangrove fauna; Tympanotonus fuscatus (periwinkle), Periophthalmus barbarous (mudskipper) and Guinearma (Sesarma) alberti (West African Sesarmid Crab) was investigated utilizng atomic absorbance spectrophotometery. Faunal sampling was conducted at five (5) sites in the Falcorp wetland area of Warri, Delta State, once monthly for an eighteen (18) month period. Maximal mean Fe and Zn values; 349.7 9 µg/g, dried wt ±15.64 and 16.92 µg/g, dried wt ±1.65 were recorded for the respective mudskipper and crab samples while minimal mean Fe and Zn values; 124.14 µg/g, dried wt ±7.85 and 7.71 µg/g, dried wt ± 0.96 were documented for the digested periwinkle tissues. The differences in the mean Fe, Zn, Cu and Cd values was siginificantly different at different levels (P<0.001, P <0.01 and P<0.05). The detection of significant bioconcentration of these metals especially Cd, is a possible indication of the wide reaching deletrious ecological effects of anthropogenic activities in the affected area. Keywords: Falcorp mangrove swamp, Bioaccumulation, Trace metal, benthic bio-indicator

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Chemical Composition and Metal Speciation in Porewaters from the Upper Qu’Appelle River Basin, Saskatchewan

Water Quality Research Journal ◽

10.2166/wqrj.1993.005 ◽

1993 ◽

Vol 28 (1) ◽

pp. 83-110 ◽

Cited By ~ 1

Author(s):

Richard E. Farrell ◽

Jae E. Yang ◽

P. Ming Huang ◽

Wen K. Liaw

Keyword(s):

Amino Acids ◽

Trace Metal ◽

River Basin ◽

Drainage Basin ◽

Metal Speciation ◽

Anthropogenic Activities ◽

High Concentration ◽

Metal Concentrations ◽

Carbonate Equilibria ◽

The Impact

Abstract Porewater samples from the upper Qu’Appelle River basin in Saskatchewan, Canada, were analyzed to obtain metal, inorganic ligand and amino add profiles. These data were used to compute the aqueous speciation of the metals in each porewater using the computer program GEOCHEM-PC. The porewaters were classified as slightly to moderately saline. Metal concentrations reflected both the geology of the drainage basin and the impact of anthropogenic activities. Whereas K and Na were present almost entirely as the free aquo ions, carbonate equilibria dominated the speciation of Ca. Mg and Mn (the predominant metal ligand species were of the type MCO3 (s). MCO30. and MHCO3+). Trace metal concentrations were generally within the ranges reported for non-polluted freshwater systems. Whereas the speciation of the trace metals Cr(III) and Co(II) was dominated by carbonate equilibria, Hg(II)-, Zn(II)- and Fe(II)-speciation was dominated by hydroxy-metal complexes of the type M(OH)+ and M(OH)2°. The speciation of Fe(III) was dominated by Fe(OH)3 (s). In porewaters with high chloride concentrations (> 2 mM), however, significant amounts of Hg(II) were bound as HgCl20 and HgClOH0. The aqueous speciation of Al was dominated by Al(OH)4− and Al2Si2O4(OH)6 (s). Total concentrations of dissolved free amino acids varied from 15.21 to 25.17 umole L−1. The most important metal scavenging amino acids were histidine (due to high stability constants for the metal-histidine complexes) and tryptophan (due to its relatively high concentration in the porewaters. i.e., 5.96 to 7.73 umole L−1). Secondary concentrations of various trace metal-amino add complexes were computed for all the porewaters, but metal-amino acid complexes dominated the speciation of Cu(II) in all the porewaters and Ni(II) in two of the porewaters.

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Marine ammonia-oxidising archaea and bacteria occupy distinct iron and copper niches

ISME Communications ◽

10.1038/s43705-021-00001-7 ◽

2021 ◽

Vol 1 (1) ◽

Author(s):

Roxana T. Shafiee ◽

Poppy J. Diver ◽

Joseph T. Snow ◽

Qiong Zhang ◽

Rosalind E. M. Rickaby

Keyword(s):

Comparative Genomics ◽

Trace Metals ◽

Trace Metal ◽

Ammonia Oxidation ◽

Testable Hypothesis ◽

Niche Separation ◽

Toxicity Threshold ◽

Geologic Time ◽

Additional Explanation ◽

Ammonia Oxidising Archaea

AbstractAmmonia oxidation by archaea and bacteria (AOA and AOB), is the first step of nitrification in the oceans. As AOA have an ammonium affinity 200-fold higher than AOB isolates, the chemical niche allowing AOB to persist in the oligotrophic ocean remains unclear. Here we show that marine isolates, Nitrosopumilus maritimus strain SCM1 (AOA) and Nitrosococcus oceani strain C-107 (AOB) have contrasting physiologies in response to the trace metals iron (Fe) and copper (Cu), holding potential implications for their niche separation in the oceans. A greater affinity for unchelated Fe may allow AOB to inhabit shallower, euphotic waters where ammonium supply is high, but competition for Fe is rife. In contrast to AOB, AOA isolates have a greater affinity and toxicity threshold for unchelated Cu providing additional explanation to the greater success of AOA in the marine environment where Cu availability can be highly variable. Using comparative genomics, we predict that the proteomic and metal transport basis giving rise to contrasting physiologies in isolates is widespread across phylogenetically diverse marine AOA and AOB that are not yet available in pure culture. Our results develop the testable hypothesis that ammonia oxidation may be limited by Cu in large tracts of the open ocean and suggest a relatively earlier emergence of AOB than AOA when considered in the context of evolving trace metal availabilities over geologic time.

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Significance of building and plumbing specifics on trace metal concentrations in drinking water

Canadian Journal of Civil Engineering ◽

10.1139/l91-111 ◽

1991 ◽

Vol 18 (6) ◽

pp. 893-903 ◽

Cited By ~ 11

Author(s):

Inderjit Singh ◽

Donald S. Mavinic

Keyword(s):

Drinking Water ◽

Trace Metals ◽

Trace Metal ◽

Water Samples ◽

First Flush ◽

Single Family ◽

Metal Concentrations ◽

Building Height ◽

High Rise ◽

Family House

Samples were taken from 72 high-rise apartment suites (6 suites in 12 individual high-rise towers) and 60 single-family houses located within the Greater Vancouver Regional District. The influence of the following factors on trace metal concentrations in 1-L first-flush drinking water samples and “running” hot water samples was investigated: building height, location, plumbing age, type of plumbing, and type of building. Results of this survey show that with the exception of building height, all factors had a correlation with one or more of the trace metals investigated. The trace metals examined were lead, copper, iron, and zinc. Lead was influenced primarily by building type, copper by plumbing age and type of plumbing, and iron by location. Elevated lead levels were associated with high-rise samples. New copper plumbing systems resulted in high copper levels. Highest iron levels in the drinking water were measured in the East Vancouver location. Zinc did not show a distinct correlation with any of the factors investigated. Brass faucets were the primary source of zinc in tap water. They also contributed substantially to the lead detected in the 1-L first-flush sample. Metal concentrations measured in the high-rise and house samples were compared with the U.S. Environmental Protection Agency's (USEPA) maximum contaminant levels (MCLs) and the proposed “no-action” level for lead. In high-rise samples, the 0.01 mg/L “no-action” level proposed for lead was exceeded in 43% of the samples, and 62% of the samples exceeded the current 1.0 mg/L MCL standard for copper. In single-family house samples, these values were 47% and 73%, respectively. The average lead concentrations were 0.020 mg/L for all high-rise samples and 0.013 mg/L for house samples. Regulatory levels stated above would still be exceeded in 6% of the cases for lead and 9% of the cases for copper, even after prolonged flushing of the tap in a high-rise building. In all cases associated with single-family houses, flushing the cold water tap for 5 minutes was successful in achieving compliance levels. Key words: aggressive water, compliance, corrosive, drinking water, first-flush, GVRD, high-rise, single-family house, trace metals, USEPA.

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Trace Metal Distribution and Mobility in Soils after Silvicultural Thinning and Burning

Journal of Agricultural Science ◽

10.5539/jas.v9n5p83 ◽

2017 ◽

Vol 9 (5) ◽

pp. 83

Author(s):

Ngowari Jaja ◽

Monday Mbila ◽

Yong Wang

Keyword(s):

Trace Metal ◽

Management Practices ◽

Soil Depth ◽

Anthropogenic Activities ◽

Block Design ◽

Forest Health ◽

Soil Surface ◽

Parent Material ◽

Design Experiment ◽

Randomized Block Design

Silvicultural thinning and burning are common management practices that are widely used to address ecosystem problems such as tree stocking and general forest health. However, high-severity fire has variable effects on soils, resulting in damages which are directly or indirectly reflected on the trace metal chemistry of the soil. This study was conducted to evaluate the trace metal variation at the Bankhead National Forest in Northern Alabama following the silvicultural thinning and burning. The experimental site had treatments consisting of two burning patterns and three levels of thinning as part of an overall treatment of three burning patterns and three levels of thinning applied to nine treatment plots to fit a completely randomized block design experiment. Four treatments sites were used for this study and samples were collected from soil profile pits excavated at representative plots within each treatment. The samples were analyzed for trace metals-As, Cu, Ni, Zn and Pb-using Perkin Elmer 2100 ICP-OES. Post treatment samples indicated that the trace metal concentrations generally decreased with soil depth. Copper, Ni, and Zn at the Pre-burn site gradually increased with depth to a maximum concentration at about 50 cm below the soil surface. Arsenic in the surface horizons increased by 156% in the burn-only sites, 54% in the thin-only treatment, 30% for the burn and thin treatments. Such differences were unlikely due to differences in the geochemistry of the parent material, but likely due to anthropogenic activities and possibly the forest management practices in question.

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Trace Metal Contamination Characteristics and Health Risks Assessment ofCommelina africanaL. and Psammitic Sandflats in the Niger Delta, Nigeria

Applied and Environmental Soil Science ◽

10.1155/2016/8178901 ◽

2016 ◽

Vol 2016 ◽

pp. 1-14 ◽

Cited By ~ 5

Author(s):

Nsikak U. Benson ◽

Paul A. Enyong ◽

Omowunmi H. Fred-Ahmadu

Keyword(s):

Trace Metal ◽

Niger Delta ◽

Anthropogenic Activities ◽

Hazard Quotient ◽

Risk Index ◽

Sediment Quality ◽

Hazard Index ◽

Adult Males ◽

Metal Concentrations ◽

Metal Levels

The purpose of this study was to investigate and quantify trace metal concentrations inCommelina africanaL. and psammitic sandflats from an intertidal coastal ecosystem in Niger Delta, Nigeria, and to evaluate their spatial distribution, degree of contamination, and source apportionment. The environmental risks associated with soil contamination were elaborately assessed using potential ecological risk index, sediment quality guidelines, and enrichment relative to background levels. The mean concentrations of Cd, Cr, Ni, Pb, and Zn in sandflat soil samples are0.76±9.0×10-2,7.39±8.7×10-1,2.28±0.35,0.024±4.0×10-3, and74.51±2.55 mg/kg, respectively. Metal levels indicate strong variability with sampling sites. The order of trace metal concentrations in theCommelina africanaL. samples isZn>Ni>Cr>Pb>Cd. The concentrations varied with the sample locations; and the levels of Pb (0.05 to 0.08 mg/kg) at all locations are found to be significantly below permissible level of 0.3 mg/kg. Potential sources of metal loadings may be associated with localised or diffused anthropogenic activities. The average carcinogenic risks are below1.0×10-6threshold values, and the sandflat soils are not considered to pose significant health effects to children and adult males and females. However, the carcinogenicity and noncarcinogenicity risks ranking decrease following the orderchildren>adult males>adult females. Comparatively, the hazard quotient and hazard index indicate that the psammitic sandflats might pose a health risk to children in future.

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Atmospheric trace metals measured at a regional background site (Welgegund) in South Africa

Atmospheric Chemistry and Physics ◽

10.5194/acp-17-4251-2017 ◽

2017 ◽

Vol 17 (6) ◽

pp. 4251-4263 ◽

Cited By ~ 19

Author(s):

Andrew D. Venter ◽

Pieter G. van Zyl ◽

Johan P. Beukes ◽

Micky Josipovic ◽

Johan Hendriks ◽

...

Keyword(s):

South Africa ◽

Trace Metals ◽

Trace Metal ◽

Size Fraction ◽

Abundant Species ◽

Metal Species ◽

Metal Concentrations ◽

Igneous Complex ◽

Size Fractions ◽

Bushveld Igneous Complex

Abstract. Atmospheric trace metals can cause a variety of health-related and environmental problems. Only a few studies on atmospheric trace metal concentrations have been conducted in South Africa. Therefore the aim of this study was to determine trace metal concentrations in aerosols collected at a regional background site, i.e. Welgegund, South Africa. PM1, PM1–2. 5 and PM2. 5–10 samples were collected for 13 months, and 31 atmospheric trace metal species were detected. Atmospheric iron (Fe) had the highest concentrations in all three size fractions, while calcium (Ca) was the second-most-abundant species. Chromium (Cr) and sodium (Na) concentrations were the third- and fourth-most-abundant species, respectively. The concentrations of the trace metal species in all three size ranges were similar, with the exception of Fe, which had higher concentrations in the PM1 size fraction. With the exception of titanium (Ti), aluminium (Al) and manganese (Mg), 70 % or more of the trace metal species detected were in the smaller size fractions, which indicated the influence of industrial activities. However, the large influence of wind-blown dust was reflected by 30 % or more of trace metals being present in the PM2. 5–10 size fraction. Comparison of trace metals determined at Welgegund to those in the western Bushveld Igneous Complex indicated that at both locations similar species were observed, with Fe being the most abundant. However, concentrations of these trace metal species were significantly higher in the western Bushveld Igneous Complex. Fe concentrations at the Vaal Triangle were similar to levels thereof at Welgegund, while concentrations of species associated with pyrometallurgical smelting were lower. Annual average Ni was 4 times higher, and annual average As was marginally higher than their respective European standard values, which could be attributed to regional influence of pyrometallurgical industries in the western Bushveld Igneous Complex. All three size fractions indicated elevated trace metal concentrations coinciding with the end of the dry season, which could partially be attributed to decreased wet removal and increases in wind generation of particulates. Principal component factor analysis (PCFA) revealed four meaningful factors in the PM1 size fraction, i.e. crustal, pyrometallurgical-related and Au slimes dams. No meaningful factors were determined for the PM1–2. 5 and PM2. 5–10 size fractions, which was attributed to the large influence of wind-blown dust on atmospheric trace metals determined at Welgegund. Pollution roses confirmed the influence of wind-blown dust on trace metal concentrations measured at Welgegund, while the impact of industrial activities was also substantiated.

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