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Gao Z, Cizdziel JV, Wontor K, Olubusoye BS. Adsorption/desorption of mercury (II) by artificially weathered microplastics: Kinetics, isotherms, and influencing factors. Environ Pollut 2023; 337:122621. [PMID: 37757936 DOI: 10.1016/j.envpol.2023.122621] [Citation(s) in RCA: 1] [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: 05/18/2023] [Revised: 09/23/2023] [Accepted: 09/25/2023] [Indexed: 09/29/2023]
Abstract
While both mercury (Hg) and microplastics (MPs) are well-studied global pollutants, comparatively little is known about the interactions between them and the mobilization of Hg from MPs into organisms. We examined the affinity of Hg(II) to artificially weathered MPs, including polyamide (w-PA), polyethylene (w-PE), polyethylene terephthalate (w-PET), polyester fibers (w-PEST), polyvinyl chloride (w-PVC), and polylactic acid (w-PLA), along with crumb rubber (CR) and PE collected from a wastewater treatment plant (WWTP-PE). WWTP-PE, CR, and w-PEST had particularly high Hg(II) affinities, which can be attributed to electrostatic interaction and pore filling. The adsorption followed a pseudo-second-order kinetic process and fitted the Freundlich model, suggesting multi-step (mass transfer and intraparticle diffusion) and heterogeneous adsorptions. Hydrochemical conditions (pH, dissolved organic matter (DOM), salinity and co-existent metal ions) all impacted Hg-MP behavior. Changes in Hg speciation and MP surface properties contributed to the different Hg(II) adsorption capacities for the MPs. Weathering of MPs generally increased the adsorption of Hg(II) onto MPs, but CR, PET and PEST did not follow this trend. Less than 3% of adsorbed Hg(II) was mobilized from the MPs in freshwater, but that increased up to 73% under simulated avian digestive conditions, suggesting increased bioavailability of Hg(II) from ingested MPs. Overall, weathered MPs adsorb and retain Hg(II) under environmentally relevant conditions but desorb much of it in simulated avian digestion fluid, suggesting that birds that ingest MPs may have increased Hg(II) exposure.
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Affiliation(s)
- Zhiqiang Gao
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA
| | - James V Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA.
| | - Kendall Wontor
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA
| | - Boluwatife S Olubusoye
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA
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Olubusoye BS, Cizdziel JV, Bee M, Moore MT, Pineda M, Yargeau V, Bennett ER. Toxic Tire Wear Compounds (6PPD-Q and 4-ADPA) Detected in Airborne Particulate Matter Along a Highway in Mississippi, USA. Bull Environ Contam Toxicol 2023; 111:68. [PMID: 37940736 DOI: 10.1007/s00128-023-03820-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 10/11/2023] [Indexed: 11/10/2023]
Abstract
Tire wear particles (TWPs) are a major category of microplastic pollution produced by friction between tires and road surfaces. This non-exhaust particulate matter (PM) containing leachable toxic compounds is transported through the air and with stormwater runoff, leading to environmental pollution and human health concerns. In the present study, we collected airborne PM at varying distances (5, 15 and 30 m) along US Highway 278 in Oxford, Mississippi, USA, for ten consecutive days using Sigma-2 passive samplers. Particles (~ 1-80 μm) were passively collected directly into small (60 mL) wide-mouth separatory funnels placed inside the samplers. Particles were subsequently subjected to solvent extraction, and extracts were analyzed for TWP compounds by high resolution orbitrap mass spectrometry. This pilot study was focused solely on qualitative analyses to determine whether TWP compounds were present in this fraction of airborne PM. The abundance of airborne TWPs increased with proximity to the road with deposition rates (TWPs cm-2 day-1) of 23, 47, and 63 at 30 m, 15 m, and 5 m from the highway, respectively. Two common TWP compounds (6PPD-Q and 4-ADPA) were detected in all samples, except the field blank, at levels above their limits of detection, estimated at 2.90 and 1.14 ng L-1, respectively. Overall, this work suggests airborne TWPs may be a potential inhalation hazard, particularly for individuals and wildlife who spend extended periods outdoors along busy roadways. Research on the bioavailability of TWP compounds from inhaled TWPs is needed to address exposure risk.
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Affiliation(s)
- Boluwatife S Olubusoye
- Department of Chemistry and Biochemistry, University of Mississippi, Oxford, MS, 38677, USA
| | - James V Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, Oxford, MS, 38677, USA.
| | - Matthew Bee
- Department of Chemistry and Biochemistry, University of Mississippi, Oxford, MS, 38677, USA
| | - Matthew T Moore
- Water Quality and Ecology Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Oxford, MS, 38655, USA
| | - Marco Pineda
- Department of Chemical Engineering, McGill University, Montreal, QC, Canada
| | - Viviane Yargeau
- Department of Chemical Engineering, McGill University, Montreal, QC, Canada
| | - Erin R Bennett
- School of the Environment, Trent University, Peterborough, ON, Canada
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Gao Z, Wontor K, Cizdziel JV. Labeling Microplastics with Fluorescent Dyes for Detection, Recovery, and Degradation Experiments. Molecules 2022; 27:7415. [PMID: 36364240 PMCID: PMC9653731 DOI: 10.3390/molecules27217415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 09/30/2022] [Revised: 10/22/2022] [Accepted: 10/24/2022] [Indexed: 11/06/2022] Open
Abstract
Staining microplastics (MPs) for fluorescence detection has been widely applied in MP analyses. However, there is a lack of standardized staining procedures and conditions, with different researchers using different dye concentrations, solvents, incubation times, and staining temperatures. Moreover, with the limited types and morphologies of commercially available MPs, a simple and optimized approach to making fluorescent MPs is needed. In this study, 4 different textile dyes, along with Nile red dye for comparison, are used to stain 17 different polymers under various conditions to optimize the staining procedure. The MPs included both virgin and naturally weathered polymers with different sizes and shapes (e.g., fragments, fibers, foams, pellets, beads). We show that the strongest fluorescence intensity occurred with aqueous staining at 70 °C for 3 h with a dye concentration of 5 mg/mL, 55 mg/mL, and 2 µg/mL for iDye dyes, Rit dyes, and Nile red, respectively. Red fluorescent signals are stronger and thus preferred over green ones. The staining procedure did not significantly alter the surface, mass, and chemical characteristics of the particles, based on FTIR and stereomicroscopy. Stained MPs were spiked into freshwater, saltwater, a sediment slurry, and wastewater-activated sludge; even after several days, the recovered particles are still strongly fluoresced. The approach described herein for producing customized fluorescent MPs and quantifying MPs in laboratory-controlled experiments is both straightforward and simple.
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Affiliation(s)
| | | | - James V. Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS 38677, USA
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Sheng Y, Liu Y, Wang K, Cizdziel JV, Wu Y, Zhou Y. Ecotoxicological effects of micronized car tire wear particles and their heavy metals on the earthworm (Eisenia fetida) in soil. Sci Total Environ 2021; 793:148613. [PMID: 34182439 DOI: 10.1016/j.scitotenv.2021.148613] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [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: 12/29/2020] [Revised: 04/01/2021] [Accepted: 06/18/2021] [Indexed: 06/13/2023]
Abstract
As one of the most common and persistent emerging human-made pollutants, microplastics (MPs) have become a global environmental problem. Although many studies have demonstrated the impact of MPs on aquatic organisms, the potential effects on terrestrial fauna are relatively unknown, even though soil is a major sink for plastic pollution. In this study, earthworms (Eisenia fetida) were exposed to MPs from tires (TMPs) in artificial soil at different TMP concentrations (0, 1, 5, 10, and 20%, w/w), at different TMP size fractions (2 mm-350 μm; 350 μm-50 μm; 50 μm-25 μm; and <25 μm), and time periods (14 and 28 days). The purpose was to evaluate the impact of TMPs on the bioaccumulation of heavy metals (Zn, Cd, and Pb) and levels of oxidative stress in the earthworms. Fluorescence imaging of TMPs stained with Nile red dye clearly showed that the worms had ingested the TMPs, with smaller particles preferentially consumed. The ingested TMPs had altered the surface morphology, degradation that increased surface area and uptake of heavy metals into the organisms. Earthworms exposed to TMPs at the higher concentrations showed clear signs of oxidative stress, with significantly (p < 0.05) increased catalase and peroxidase activity and lipid peroxidation levels, and reduced activity of superoxide dismutase and glutathione S-transferase. SOD, POD, and CAT are important cell protection enzymes that prevent excessive levels of reactive oxygen species in cells. MDA represents the total scavenging ability of free radicals in the tissue. SOD decreases and MDA accumulates rapidly. GST has a detoxification effect. Overall, this study adds to the growing body of evidence that TMPs are harmful to certain terrestrial organisms.
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Affiliation(s)
- Yingfei Sheng
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yi Liu
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Kewei Wang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - James V Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA
| | - Yichun Wu
- Zhoushan Institute for Food and Drug Control, Zhoushan 316012, China
| | - Ying Zhou
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China; Environmental Microplastic Pollution Research Center, Zhejiang University of Technology, Hangzhou 310014, China.
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Al Bakain RZ, Al-Degs YS, Cizdziel JV, Elsohly MA. Linear discriminant analysis based on gas chromatographic measurements for geographical prediction of USA medical domestic cannabis. ACTA CHROMATOGR 2021. [DOI: 10.1556/1326.2020.00782] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
AbstractFifty four domestically produced cannabis samples obtained from different USA states were quantitatively assayed by GC–FID to detect 22 active components: 15 terpenoids and 7 cannabinoids. The profiles of the selected compounds were used as inputs for samples grouping to their geographical origins and for building a geographical prediction model using Linear Discriminant Analysis. The proposed sample extraction and chromatographic separation was satisfactory to select 22 active ingredients with a wide analytical range between 5.0 and 1,000 µg/mL. Analysis of GC-profiles by Principle Component Analysis retained three significant variables for grouping job (Δ9-THC, CBN, and CBC) and the modest discrimination of samples based on their geographical origin was reported. PCA was able to separate many samples of Oregon and Vermont while a mixed classification was observed for the rest of samples. By using LDA as a supervised classification method, excellent separation of cannabis samples was attained leading to a classification of new samples not being included in the model. Using two principal components and LDA with GC–FID profiles correctly predict the geographical of 100% Washington cannabis, 86% of both Oregon and Vermont samples, and finally, 71% of Ohio samples.
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Affiliation(s)
- Ramia Z. Al Bakain
- 1Department of Chemistry, School of Science, The University of Jordan, P.O. Box 11942, Amman, Jordan
| | - Yahya S. Al-Degs
- 2Chemistry Department, The Hashemite University, P.O. Box 150459, Zarqa, Jordan
| | - James V. Cizdziel
- 3Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA
| | - Mahmoud A. Elsohly
- 4National Center for Natural Products Research, University, MS, 38677-1848, USA
- 5Department of Pharmaceutics and Drug Delivery, School of Pharmacy, University of Mississippi, University, MS, 38677, USA
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Liu Y, Li R, Yu J, Ni F, Sheng Y, Scircle A, Cizdziel JV, Zhou Y. Separation and identification of microplastics in marine organisms by TGA-FTIR-GC/MS: A case study of mussels from coastal China. Environ Pollut 2021; 272:115946. [PMID: 33190986 DOI: 10.1016/j.envpol.2020.115946] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [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: 07/11/2020] [Revised: 09/27/2020] [Accepted: 10/26/2020] [Indexed: 06/11/2023]
Abstract
Microplastics are ubiquitous in the marine environment but characterizing them in marine organisms is challenging. Herein we describe a method to detect, identify, and quantify microplastics in marine mussels (Mytilus edulis) using thermal gravimetric analysis - Fourier Transform infrared spectroscopy - gas chromatography mass spectrometry (TGA-FTIR-GC/MS) after extracting and isolating the microplastics using chemical digestion, density separation, and filtration. Combining the three instrumental techniques adds discriminatory power as temperature profiles, chromatograms, and vibrational and mass spectra differ among common plastics. First, we tested several digestion schemes after spiking the mussels with plastics commonly found in the marine environment, including polyethylene (PE), polystyrene (PS), polypropylene (PP) and polyvinyl chloride (PVC). KOH (10%, w/v) was the most suitable reagent, providing good recoveries (>97%) without degrading the microplastics. We show that the technique TGA-FTIR-GC/MS can be optimized to readily determine both the type (polymer) and amount (mass) of microplastics in the sample. Applied to 100 mussels from each of six locations along the coast of China, we found an average of 0.58 mg of plastic per kg of tissue (range 0.16-1.71 mg/kg), with PE being the most abundant type of plastic measured. Among the coastal cities, mussels from Dalian had the highest microplastic content. Overall, we demonstrate that the method is a powerful technique to quantify masses of microplastics in marine mussels, a species commonly used as a bioindicator of pollution, and may be applied to other biota as well.
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Affiliation(s)
- Yi Liu
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Ruojia Li
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Jianping Yu
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Fengli Ni
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Yingfei Sheng
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Austin Scircle
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA
| | - James V Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA
| | - Ying Zhou
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China; Research Center of Analysis and Measurement, Zhejiang University of Technology, Hangzhou, 310014, China; Environmental Microplastic Pollution Research Center, Zhejiang University of Technology, Hangzhou, 310014, China.
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Al Bakain RZ, Al-Degs YS, Cizdziel JV, Elsohly MA. Comprehensive chromatographic profiling of cannabis from 23 USA States marketed for medical purposes. ACTA CHROMATOGR 2020. [DOI: 10.1556/1326.2020.00767] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
AbstractIn this research, cannabis varieties represent 23 USA States were assayed by GC-FID to generate their complex chemical profiles informative for plants clustering. Results showed that 45 cannabinoids and terpenoids were quantified in all plant samples, where 8 cannabinoids and 18 terpenoids were identified. Among organics, Δ9-THC, CBN (cannabinoids) and Fenchol (terpenoid) not only showed the highest levels overall contents, but also were the most important compounds for cannabis clustering. Among States, Washington, Oregon, California and Hawaii have the highest cannabis content. GC-FID data were subjected to PCA and HCA to find (1) the variations among cannabis chemical profiles as a result of growing environment, (2) to reveal the compounds that were responsible for grouping cultivars between clusters and (3) finally, to facilitate the future profile prediction and States clustering of unknown cannabis based on the chemical profile. The 23 cannabis USA States were grouped into three clusters based on only Δ9-THC, CBN, C1 and Fenchol content. Cannabis classification based on GC-profile will meet the practical needs of cannabis applications in clinical research, industrial production, patients' self-production, and contribute to the standardization of commercially-available cannabis cultivars in USA.
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Affiliation(s)
- Ramia Z. Al Bakain
- 1Department of Chemistry, School of Science, The University of Jordan, 11942, Amman, Jordan
| | - Yahya S. Al-Degs
- 2Chemistry Department, The Hashemite University, 150459, Zarqa, Jordan
| | - James V. Cizdziel
- 3Department of Chemistry and Biochemistry, University of Mississippi, University, MS 38677, USA
| | - Mahmoud A. Elsohly
- 4National Center for Natural Products Research, University, MS 38677-1848, USA
- 5Department of Pharmaceutics and Drug Delivery, School of Pharmacy, University of Mississippi University, MS 38677, USA
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Jeon B, Cizdziel JV. Determination of Metals in Tree Rings by ICP-MS Using Ash from a Direct Mercury Analyzer. Molecules 2020; 25:molecules25092126. [PMID: 32370081 PMCID: PMC7248844 DOI: 10.3390/molecules25092126] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 04/28/2020] [Accepted: 04/30/2020] [Indexed: 11/16/2022] Open
Abstract
Elemental profiles in cores of tree trunks (bole wood) have been used for environmental monitoring and reconstruction of metal pollution history. Mercury (Hg) is a global pollutant that can be accurately measured in tree rings in a simple and pragmatic fashion using a direct mercury analyzer (DMA) that is based on thermal decomposition, amalgamation, and atomic absorption spectrophotometry. In this feasibility study, we demonstrate that the ash remaining after the DMA analyses can be used to quantify a wide range of other non-volatile elements (Ba, Be, Co, Cr, Cu, Fe, Ga, Mg, Mn, Ni, Pb, Sr, Th, and U) in that same sample of wood by inductively coupled plasma mass spectrometry (ICP-MS) after microwave-assisted acid digestion. Other elements (Ag, Cd, Cs, Rb, Tl, and V) exhibited poor recoveries, possibly due to losses during sample preparation. We assessed the accuracy with reference materials, spikes, and by comparison with EPA Method 3052 (Microwave Assisted Acid Digestion of Siliceous and Organically Based Matrices). For the first group of elements (deemed suitable for the method), recoveries ranged between 80% and 120% and the relative standard deviation was generally < 15%, indicating acceptable precision. We applied the method to five species of trees: eastern red cedar (Juniperus virginiana), loblolly pine (Pinus taeda), shortleaf pine (Pinus echinata), white oak (Quercus alba), and tulip poplar (Liriodendron tulipifera) from Holly Springs National Forest in north Mississippi, USA. Mercury concentrations (ng/g ± SE) were highest in the cedar (1.8 ± 0.3; n = 5), followed by loblolly pine (1.6 ± 0.3, n = 3), shortleaf pine (1.2 ± 0.2; n = 3), oak (1.1 ± 0.2; n = 5), and poplar (0.5 ± 0.1; n = 5). Concentrations of other elements were generally Fe > Mg > Ba ≈ Sr ≈ Mn > Cr ≈ Cu > Ni ≈ Rb > Co > Ga ≈ Ag, with the other elements generally below the method detection limit (MDL). Overall, we showed that the DMA can be used to not only determine total Hg in segments of tree core, but can serve as the ashing step in the preparation of wood for ICP-MS analysis, thus allowing the determination of non-volatile elements along with Hg in the very same sample.
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Scircle A, Cizdziel JV, Missling K, Li L, Vianello A. Single-Pot Method for the Collection and Preparation of Natural Water for Microplastic Analyses: Microplastics in the Mississippi River System during and after Historic Flooding. Environ Toxicol Chem 2020; 39:986-995. [PMID: 32102117 DOI: 10.1002/etc.4698] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/13/2020] [Accepted: 02/24/2020] [Indexed: 05/25/2023]
Abstract
We describe a simple single-pot method for collection and preparation of natural water for microplastic analyses. The method prepares samples in the same vessel (mason jars) that they are collected in right up until the microplastics are transferred onto filters or spectroscopic windows for analyses. The method minimized contamination, degradation, and losses, while increasing recoveries and throughput when compared with conventional sieving. We applied it to surface grab samples collected from the Mississippi River and its major tributaries during and after historic flooding in 2019. Microplastics (>~30 µm) were quantified using Nile red fluorescence detection, and a small subset of samples were identified by micro-Fourier transform infrared imaging spectroscopy. Concentrations were lower during the flooding, likely due to dilution. Concentrations ranged from approximately 14 microplastics/L in the Tennessee River during flooding to approximately 83 microplastics/L in the Ohio River during low-flow (summer) conditions. Loads of microplastics tended to increase downriver and ranged from approximately 87 to approximately 129 trillion microplastics/d near New Orleans. Most of the microplastics (>60%) were in the lower size fraction (~30-90 µm) and consisted primarily of fragments (~85%), followed by fibers (~8%) and beads (~7%), with polyester, polyethylene, polypropylene, and polyacrylate as the primary microplastic types. Overall, we demonstrate that the single-pot method is effective and versatile and, because it uses relatively inexpensive and easily assembled materials, can be adapted for microplastic surveys worldwide, especially those involving sample collection by volunteers from the community and schools. Environ Toxicol Chem 2020;39:986-995. © 2020 SETAC.
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Affiliation(s)
- Austin Scircle
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi, USA
| | - James V Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi, USA
| | - Klara Missling
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi, USA
| | - Libby Li
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi, USA
| | - Alvise Vianello
- Department of the Built Environment, Aalborg University, Aalborg Øst, Denmark
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Li R, Liu Y, Sheng Y, Xiang Q, Zhou Y, Cizdziel JV. Effect of prothioconazole on the degradation of microplastics derived from mulching plastic film: Apparent change and interaction with heavy metals in soil. Environ Pollut 2020; 260:113988. [PMID: 32369895 DOI: 10.1016/j.envpol.2020.113988] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [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: 06/29/2019] [Revised: 01/04/2020] [Accepted: 01/13/2020] [Indexed: 05/06/2023]
Abstract
Microplastic pollution is a major global environmental problem in both aquatic and terrestrial environments. Pesticides are frequently applied to agricultural soil to reduce the effects of pests on crops, but may also affect the degradation of plastics. In this study, we generated microplastics from polyethylene (PE) film and biodegradable poly(butylene adipate-co-terephthalate) (PBAT) film and determined (1) the effect of prothioconazole on degradation of the microplastics, and (2) the adsorption and release characteristics of heavy metals (Cr, Cu, As, Pb, Ba, and Sn) by the microplastics during degradation process. Changes of surface functional groups and morphologies were measured by FTIR and SEM, while metal concentrations were determined by ICPMS. Prothioconazole was found to promote plastic degradation. PBAT degraded faster and adsorbed more heavy metals from the soil than PE. Whether the microplastics adsorb or release heavy metals depended on the metal and their concentrations. Prothioconazole inhibited the adsorption of Cr, As, Pb and Ba by microplastics, promoted the adsorption of Cu, and had no significant effect for Sn. These results can help to assess the ecological risk of microplastic pollution from plastic mulch when combined with heavy metals.
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Affiliation(s)
- Ruojia Li
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Yi Liu
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Yingfei Sheng
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Qingqing Xiang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Ying Zhou
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China; Research Center of Analysis and Measurement, Zhejiang University of Technology, Hangzhou, 310014, China; Environmental Microplastic Pollution Research Center, Zhejiang University of Technology, Hangzhou, 310014, China.
| | - James V Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi University, MS, 38677, USA
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Gao Z, Cai L, Liu M, Zhang Z, Gao B, Zhao W, Cizdziel JV, Chen L. Total mercury and methylmercury migration and transformation in an A 2/O wastewater treatment plant. Sci Total Environ 2020; 710:136384. [PMID: 31927291 DOI: 10.1016/j.scitotenv.2019.136384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 12/05/2019] [Accepted: 12/26/2019] [Indexed: 06/10/2023]
Abstract
Municipal wastewater treatment plants (MWTPs) serve an essential role in reducing mercury (Hg) pollution. However, few studies quantified the transport and transformation of Hg through MWTPs, particularly plants based on the anaerobic-anoxic-aerobic (A2/O) process. Here, we present a mass balance for total mercury (THg) and total methylmercury (TMeHg) at the plant, and investigate the influence of pH, temperature, and dissolved oxygen on the occurrence and fate of methylmercury (MeHg) in the system. The concentrations of the THg and TMeHg in the raw sewage were 40.3 ± 26.6 ng/L (4.3 ± 2.7 g/day) and 1.9 ± 0.6 ng/L (193 ± 58 mg/day), respectively. Their concentrations in the plant's effluent water were 7.4 ± 1.5 ng/L (0.74 ± 0.2 g/day) and 0.04 ± 0.01 ng/L (3.9 ± 1.0 mg/day), corresponding to decreases of ~82% for THg and ~98% for TMeHg. Within the plant, only ~10% of the THg was removed with primary sedimentation, as Hg in the raw sewage was predominately in dissolved form. In contrast, a significant portion of TMeHg (~43%) was associated with incoming particulate matter. Much of the remaining Hg was removed in subsequent A2/O process and secondary clarifiers, with a ~78% of the THg entering the plant transferring to the dewatered sludge (concentration 1.05 ± 0.28 μg/g; 3.2 ± 0.8 g/day). These same steps decreased TMeHg in the water by ~95%, with <10% of that reduction being TMeHg transferred to the sludge (concentration 2.1 ± 1.1 ng/g; 6.2 ± 3.3 mg/day), suggesting >90% TMeHg degradation. In addition, the most important factor that impacted the variation of TMeHg concentrations was pH, then was temperature. Dissolved oxygen showed no relationship with TMeHg and DMeHg. Overall, this study demonstrates that A2/O MWTPs effectively remove MeHg from wastewater, however, sludge remains an important potential source of Hg to the environment.
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Affiliation(s)
- Zhiqiang Gao
- State Environmental Protection Key Laboratory of Urban Ecological Environment Simulation and Protection, South China Institute of Environmental Sciences, Ministry of Ecology and Environment of the People's Republic of China, Guangzhou 510655, China; Department of Chemistry and Biochemistry, University of Mississippi, MS 38677, United States
| | - Limei Cai
- College of Resources and Environment, Yangtze University, Wuhan 430100, China
| | - Ming Liu
- State Environmental Protection Key Laboratory of Urban Ecological Environment Simulation and Protection, South China Institute of Environmental Sciences, Ministry of Ecology and Environment of the People's Republic of China, Guangzhou 510655, China
| | - Zuo Zhang
- Qingyuan Environmental Monitoring station, Qingyuan 511515, China
| | - Bo Gao
- State Environmental Protection Key Laboratory of Urban Ecological Environment Simulation and Protection, South China Institute of Environmental Sciences, Ministry of Ecology and Environment of the People's Republic of China, Guangzhou 510655, China
| | - Wei Zhao
- State Environmental Protection Key Laboratory of Urban Ecological Environment Simulation and Protection, South China Institute of Environmental Sciences, Ministry of Ecology and Environment of the People's Republic of China, Guangzhou 510655, China
| | - James V Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, MS 38677, United States
| | - Laiguo Chen
- State Environmental Protection Key Laboratory of Urban Ecological Environment Simulation and Protection, South China Institute of Environmental Sciences, Ministry of Ecology and Environment of the People's Republic of China, Guangzhou 510655, China.
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Al Bakain RZ, Al-Degs YS, Cizdziel JV, Elsohly MA. Comprehensive classification of USA cannabis samples based on chemical profiles of major cannabinoids and terpenoids. J LIQ CHROMATOGR R T 2019. [DOI: 10.1080/10826076.2019.1701015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Ramia Z. Al Bakain
- Department of Chemistry, School of Science, The University of Jordan, Amman, Jordan
| | | | - James V. Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, USA
| | - Mahmoud A. Elsohly
- National Center for Natural Products Research, University, MS, USA
- Department of Pharmaceutics and Drug Delivery, School of Pharmacy, University of Mississippi, University, MS, USA
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Reddy KN, Cizdziel JV, Williams MM, Maul JE, Rimando AM, Duke SO. Glyphosate Resistance Technology Has Minimal or No Effect on Maize Mineral Content and Yield. J Agric Food Chem 2018; 66:10139-10146. [PMID: 30203974 DOI: 10.1021/acs.jafc.8b01655] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Controversy continues to exist regarding whether the transgene for glyphosate resistance (GR) and/or glyphosate applied to GR crops adversely affect plant mineral content. Field studies were conducted in 2013 and 2014 in Stoneville, MS and Urbana, IL to examine this issue in maize. At each location, the experiment was conducted in fields with no history of glyphosate application and fields with several years of glyphosate use preceding the study. Neither glyphosate nor the GR transgene affected yield or mineral content of leaves or seed, except for occasional (<5%) significant effects that were inconsistent across minerals, treatments, and environments. Glyphosate and AMPA (aminomethylphosphonic acid), a main degradation product of glyphosate, were found in leaves from treated plants, but little or no glyphosate and no AMPA was found in maize seeds. These results show that the GR transgene and glyphosate application, whether used for a single year or several years, have no deleterious effect on mineral nutrition or yield of GR maize.
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Affiliation(s)
- Krishna N Reddy
- Crop Production Systems Research Unit, USDA-ARS , P.O. Box 350, Stoneville , Mississippi 38776 , United States
| | - James V Cizdziel
- Department of Chemistry and Biochemistry , University of Mississippi , 222 Coulter Hall , University , Mississippi 38677 , United States
| | - Martin M Williams
- Global Change and Photosynthesis Research unit , USDA-ARS, 1102 S. Goodwin Avenue , Urbana , Illinois 61801 , United States
| | - Jude E Maul
- Sustainable Agricultural Systems Laboratory, USDA-ARS , 10300 Baltimore Avenue , Beltsville , Maryland 20705 , United States
| | - Agnes M Rimando
- Natural Products Utilization Research Unit, USDA-ARS , P.O. Box 1848, University , Mississippi 38677 , United States
| | - Stephen O Duke
- Natural Products Utilization Research Unit, USDA-ARS , P.O. Box 1848, University , Mississippi 38677 , United States
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Duke SO, Rimando AM, Reddy KN, Cizdziel JV, Bellaloui N, Shaw DR, Williams MM, Maul JE. Lack of transgene and glyphosate effects on yield, and mineral and amino acid content of glyphosate-resistant soybean. Pest Manag Sci 2018; 74:1166-1173. [PMID: 28547884 DOI: 10.1002/ps.4625] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [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: 01/06/2017] [Revised: 05/12/2017] [Accepted: 05/23/2017] [Indexed: 05/09/2023]
Abstract
BACKGROUND There has been controversy as to whether the glyphosate resistance gene and/or glyphosate applied to glyphosate-resistant (GR) soybean affect the content of cationic minerals (especially Mg, Mn and Fe), yield and amino acid content of GR soybean. A two-year field study (2013 and 2014) examined these questions at sites in Mississippi, USA. RESULTS There were no effects of glyphosate, the GR transgene or field crop history (for a field with both no history of glyphosate use versus one with a long history of glyphosate use) on grain yield. Furthermore, these factors had no consistent effects on measured mineral (Al, As, Ba, Cd, Ca, Co, Cr, Cs, Cu, Fe, Ga, K, Li, Mg, Mn, Ni, Pb, Rb, Se, Sr, Tl, U, V, Zn) content of leaves or harvested seed. Effects on minerals were small and inconsistent between years, treatments and mineral, and appeared to be random false positives. No notable effects on free or protein amino acids of the seed were measured, although glyphosate and its degradation product, aminomethylphosphonic acid (AMPA), were found in the seed in concentrations consistent with previous studies. CONCLUSIONS Neither glyphosate nor the GR transgene affect the content of the minerals measured in leaves and seed, harvested seed amino acid composition, or yield of GR soybean. Furthermore, soils with a legacy of GR crops have no effects on these parameters in soybean. © 2017 Society of Chemical Industry.
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Affiliation(s)
- Stephen O Duke
- U.S. Department of Agriculture-Agricultural Research Service, Natural Products Utilization Research Unit, University, MS, USA
| | - Agnes M Rimando
- U.S. Department of Agriculture-Agricultural Research Service, Natural Products Utilization Research Unit, University, MS, USA
| | - Krishna N Reddy
- USDA-ARS, Crop Production Systems Research Unit, Stoneville, MS, USA
| | - James V Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, USA
| | | | - David R Shaw
- Research and Economic Development, Mississippi State University, Mississippi State, MS, USA
| | - Martin M Williams
- USDA-ARS, Global Change and Photosynthesis Research Unit, Urbana, IL, USA
| | - Jude E Maul
- USDA-ARS, Sustainable Agricultural Systems Laboratory, Beltsville, MD, USA
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15
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Black O, Chen J, Scircle A, Zhou Y, Cizdziel JV. Adaption and use of a quadcopter for targeted sampling of gaseous mercury in the atmosphere. Environ Sci Pollut Res Int 2018; 25:13195-13202. [PMID: 29569200 DOI: 10.1007/s11356-018-1775-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [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: 01/13/2018] [Accepted: 03/13/2018] [Indexed: 06/08/2023]
Abstract
We modified a popular and inexpensive quadcopter to collect gaseous mercury (Hg) on gold-coated quartz cartridges, and analyzed the traps using cold vapor atomic fluorescence spectrometry. Flight times averaged 16 min, limited by battery life, and yielded > 5 pg of Hg, well above the limit of detection (< 0.2 pg). We measured progressively higher concentrations upon both vertical and lateral approaches to a dish containing elemental Hg, demonstrating that the method can detect Hg emissions from a point source. Using the quadcopter, we measured atmospheric Hg near anthropogenic emission sources in the mid-south USA, including a municipal landfill, coal-fired power plant (CFPP), and a petroleum refinery. Average concentrations (± standard deviation) immediately downwind of the landfill were higher at ground level and 30 m compared to 60 and 120 m (5.3 ± 0.5 ng m-3, 5.4 ± 0.7 ng m-3, 4.2 ± 0.7 ng m-3, and 2.5 ± 0.3 ng m-3, respectively). Concentrations were also higher at an urban/industrial area (Memphis) (3.3 ± 0.9 ng m-3) compared with a rural/background area (1.5 ± 0.2 ng m-3). Due to airspace flight restrictions near the CFPP and refinery, we were unable to access near-field (stack) plumes and did not observe differences between upwind and downwind locations. Overall, this study demonstrates that highly maneuverable multicopters can be used to probe Hg concentrations aloft, which may be particularly useful for evaluating Hg emissions from remote landscapes and transient sources that are inadequately characterized and leading to uncertainties in ecosystem budgets.
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Affiliation(s)
- Oscar Black
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA
| | - Jingjing Chen
- College of Chemical Engineering, Zhejiang University of Technology, No.18 Chaowang Road, Hangzhou, 310032, Zhejiang, China
| | - Austin Scircle
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA
| | - Ying Zhou
- College of Chemical Engineering, Zhejiang University of Technology, No.18 Chaowang Road, Hangzhou, 310032, Zhejiang, China.
| | - James V Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA.
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16
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Bussan DD, Ochs CA, Jackson CR, Anumol T, Snyder SA, Cizdziel JV. Concentrations of select dissolved trace elements and anthropogenic organic compounds in the Mississippi River and major tributaries during the summer of 2012 and 2013. Environ Monit Assess 2017; 189:73. [PMID: 28116606 DOI: 10.1007/s10661-017-5785-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [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: 06/23/2016] [Accepted: 01/16/2017] [Indexed: 06/06/2023]
Abstract
The Mississippi River drainage basin includes the Illinois, Missouri, Ohio, Tennessee, and Arkansas rivers. These rivers drain areas with different physiography, population centers, and land use, with each contributing a different suites of metals and wastewater contaminants that can affect water quality. In July 2012, we determined 18 elements (Be, Rb, Sr, Cd, Cs, Ba, Tl, Pb, Mg, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn) and chlorophyll-a (Chl-a) in the five major tributaries and in the Upper Mississippi River. The following summer, we determined both trace elements and 25 trace organic compounds at 10 sites in a longitudinal study of the main stem of the Mississippi River from Grafton, Illinois to Natchez, Mississippi. We detected wastewater contaminants, including pharmaceuticals and endocrine disrupting compounds, throughout the river system, with the highest concentrations occurring near urban centers (St. Louis and Memphis). Concentrations were highest for atrazine (673 ng L-1), DEET (540 ng L-1), TCPP (231 ng L-1), and caffeine (202 ng L-1). The Illinois, Missouri, and Yazoo rivers, which drain areas with intense agriculture, had relatively high concentrations of Chl-a and atrazine. However, the Ohio River delivered higher loads of contaminants to the Mississippi River, including an estimated 177 kg day-1 of atrazine, due to higher flow volumes. Concentrations of heavy metals (Ni, V, Co, Cu, Cd, and Zn) were relatively high in the Illinois River and low in the Ohio River, although dissolved metal concentrations were below US EPA maximum contaminant levels for surface water. Multivariate analysis demonstrated that the rivers can be distinguished based on elemental and contaminant profiles.
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Affiliation(s)
- Derek D Bussan
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA
| | - Clifford A Ochs
- Department of Biology, University of Mississippi, University, MS, 38677, USA
| | - Colin R Jackson
- Department of Biology, University of Mississippi, University, MS, 38677, USA
| | - Tarun Anumol
- Department of Chemical and Environmental Engineering, University of Arizona, 1133 E James E Rogers Way, Harshbarger 108, Tucson, AZ, 85721-0011, USA
- Agilent Technologies Inc., 2850 Centerville Road, Wilmington, DE, 19808, USA
| | - Shane A Snyder
- Department of Chemical and Environmental Engineering, University of Arizona, 1133 E James E Rogers Way, Harshbarger 108, Tucson, AZ, 85721-0011, USA
| | - James V Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA.
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17
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Wolff S, Brown G, Chen J, Meals K, Thornton C, Brewer S, Cizdziel JV, Willett KL. Mercury concentrations in fish from three major lakes in north Mississippi: Spatial and temporal differences and human health risk assessment. J Toxicol Environ Health A 2016; 79:894-904. [PMID: 27644342 DOI: 10.1080/15287394.2016.1194792] [Citation(s) in RCA: 3] [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: 03/30/2016] [Accepted: 05/24/2016] [Indexed: 06/06/2023]
Abstract
The goal of this study was to compare total mercury (Hg) concentrations in fish muscle tissue and assess consumption health risks of fish collected from three north Mississippi lakes (Sardis, Enid, and Grenada) that are extensively used for fishing and recreation. Largemouth bass (LMB; n = 64), channel catfish (CC; n = 72), and white crappie (WC; n = 100), which represent a range of trophic levels, were collected during spring 2013 and 2014. Creel data estimated that anglers harvested approximately 370,000 kg of WC, 27,000 kg of CC, and 15,000 kg of LMB from the lakes annually. Median Hg wet weight concentrations were highest in LMB (443 ng/g), followed by CC (211 ng/g) and WC (192 ng/g). Fish-Hg concentrations were lower than those reported in fish >10 years ago. There were significant differences between lakes consistent across species. Grenada length-normalized fish-Hg concentrations were higher than those from Enid and Sardis. Because existing consumption advisories for CC are length based, the lack of relationship between length and Hg concentration indicated that the recommendations may not be sufficiently protective. Further, five different risk assessment paradigms yielded hazard quotient (HQ) values suggesting that existing fish consumption advisories may be insufficient to protect adults and especially children from exposure to Hg.
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Affiliation(s)
- Stacy Wolff
- a Department of Chemistry and Biochemistry , University of Mississippi , University , Mississippi , USA
| | - Garry Brown
- a Department of Chemistry and Biochemistry , University of Mississippi , University , Mississippi , USA
| | - Jingjing Chen
- b College of Chemical Engineering, Zhejiang University of Technology , Hangzhou , Zhejiang , China
| | - Keith Meals
- c Mississippi Department of Wildlife , Fisheries, and Parks , University , Mississippi , USA
| | - Cammi Thornton
- d Department of BioMolecular Sciences , Environmental Toxicology Research Program, University of Mississippi , University , Mississippi , USA
| | - Steve Brewer
- e Department of Biology , University of Mississippi , University , Mississippi , USA
| | - James V Cizdziel
- a Department of Chemistry and Biochemistry , University of Mississippi , University , Mississippi , USA
| | - Kristine L Willett
- d Department of BioMolecular Sciences , Environmental Toxicology Research Program, University of Mississippi , University , Mississippi , USA
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18
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Bussan DD, Sessums RF, Cizdziel JV. Activated Carbon and Biochar Reduce Mercury Methylation Potentials in Aquatic Sediments. Bull Environ Contam Toxicol 2016; 96:536-539. [PMID: 26779648 DOI: 10.1007/s00128-016-1734-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [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: 08/21/2015] [Accepted: 01/08/2016] [Indexed: 06/05/2023]
Abstract
Much of the toxic methylmercury (MeHg) that biomagnifies in the aquatic food chain and accumulates in fish and seafood is believed to originate from microbial methylation of inorganic Hg(+2) in anoxic sediments. We examined the effect amending wetland sediments with activated carbon and biochar on Hg methylation potentials using microcosms and Hg stable isotope tracers. The inorganic (200)Hg(+2) spike was methylated at ~0.37 %/day in the untreated sediment, but that rate decreased to <0.08 %/day for the amended sediments, with 80 % and 88 % reductions in methylation rates for activated carbon and biochar amendments, respectively. Demethylation rates were relatively unchanged. Our key finding is that amending contaminated sediment with activated carbon and biochar decreases bioavailable Hg, and thus may also decrease Hg transfer into food webs. However, further research is needed to evaluate exactly how the sorbents impact Hg methylation rates and for related field studies.
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Affiliation(s)
- Derek D Bussan
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA
| | - Ryan F Sessums
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA
| | - James V Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA.
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19
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Chen J, Chakravarty P, Davidson GR, Wren DG, Locke MA, Zhou Y, Brown G, Cizdziel JV. Simultaneous determination of mercury and organic carbon in sediment and soils using a direct mercury analyzer based on thermal decomposition-atomic absorption spectrophotometry. Anal Chim Acta 2015; 871:9-17. [PMID: 25847156 DOI: 10.1016/j.aca.2015.03.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 03/02/2015] [Accepted: 03/05/2015] [Indexed: 10/23/2022]
Abstract
The purpose of this work was to study the feasibility of using a direct mercury analyzer (DMA) to simultaneously determine mercury (Hg) and organic matter content in sediment and soils. Organic carbon was estimated by re-weighing the sample boats post analysis to obtain loss-on-ignition (LOI) data. The DMA-LOI results were statistically similar (p<0.05) to the conventional muffle furnace approach. A regression equation was developed to convert DMA-LOI data to total organic carbon (TOC), which varied between 0.2% and 13.0%. Thus, mercury analyzers based on combustion can provide accurate estimates of organic carbon content in non-calcareous sediment and soils; however, weight gain from moisture (post-analysis), measurement uncertainty, and sample representativeness should all be taken into account. Sediment cores from seasonal wetland and open water areas from six oxbow lakes in the Mississippi River alluvial flood plain were analyzed. Wetland sediments generally had higher levels of Hg than open water areas owing to a greater fraction of fine particles and higher levels of organic matter. Annual loading of Hg in open water areas was estimated at 4.3, 13.4, 19.2, 20.7, 129, and 135 ng cm(-2) yr(-1) for Beasley, Roundaway, Hampton, Washington, Wolf and Sky Lakes, respectively. Generally, the interval with the highest Hg flux was dated to the 1960s and 1970s.
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Affiliation(s)
- Jingjing Chen
- College of Chemical Engineering, Zhejiang University of Technology, No. 18 Chaowang Road, Hangzhou, Zhejiang 310032, China
| | - Pragya Chakravarty
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS 38677, USA
| | - Gregg R Davidson
- Department of Geology and Geological Engineering, University of Mississippi, University, MS 38677, USA
| | - Daniel G Wren
- National Sedimentation Laboratory, United States Department of Agriculture, Agricultural Research Service, Oxford, MS 38655, USA
| | - Martin A Locke
- National Sedimentation Laboratory, United States Department of Agriculture, Agricultural Research Service, Oxford, MS 38655, USA
| | - Ying Zhou
- College of Chemical Engineering, Zhejiang University of Technology, No. 18 Chaowang Road, Hangzhou, Zhejiang 310032, China.
| | - Garry Brown
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS 38677, USA
| | - James V Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS 38677, USA.
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20
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Brown G, Sleeper K, Johnson MW, Blum JD, Cizdziel JV. Mercury concentrations, speciation, and isotopic composition in sediment from a cold seep in the northern Gulf of Mexico. Mar Pollut Bull 2013; 77:308-314. [PMID: 24269012 DOI: 10.1016/j.marpolbul.2013.09.030] [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: 06/27/2013] [Revised: 09/10/2013] [Accepted: 09/12/2013] [Indexed: 06/02/2023]
Abstract
Total-Hg, monomethylmercury (MMHg), and mercury isotopic composition was determined in sediment from a cold seep and background sites in the northern Gulf of Mexico (nGoM). Total-Hg averaged 50 ng/g (n=28), ranged from 31 to 67 ng/g, and decreased with depth (0-15 cm). MMHg averaged 0.91 ng/g (n=18), and ranged from 0.2 to 1.9 ng/g. There was no significant difference for total-Hg or MMHg between cold seep and background sites. δ(202)Hg ranged from -0.5 to -0.8‰ and becomes more negative with depth (r=0.989). Mass independent fractionation (Δ(199)Hg) was small but consistently positive (0.04-0.12‰); there was no difference between cold seeps (Δ(199)Hg = +0.09±0.03; n=7, 1SD) and background sites (Δ(199)Hg=+0.07±0.02; n=5, 1SD). This suggests that releases of hydrocarbons at the cold seep do not significantly alter Hg levels, and that cold seeps are likely not major sources of MMHg to nGoM waters.
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Affiliation(s)
- Garry Brown
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS 38677, USA
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21
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Reidy L, Bu K, Godfrey M, Cizdziel JV. Elemental fingerprinting of soils using ICP-MS and multivariate statistics: A study for and by forensic chemistry majors. Forensic Sci Int 2013; 233:37-44. [DOI: 10.1016/j.forsciint.2013.08.019] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Revised: 08/14/2013] [Accepted: 08/19/2013] [Indexed: 11/24/2022]
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Jiang Y, Cizdziel JV, Lu D. Temporal patterns of atmospheric mercury species in northern Mississippi during 2011-2012: influence of sudden population swings. Chemosphere 2013; 93:1694-1700. [PMID: 23769469 DOI: 10.1016/j.chemosphere.2013.05.039] [Citation(s) in RCA: 0] [Impact Index Per Article: 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: 11/26/2012] [Revised: 05/14/2013] [Accepted: 05/15/2013] [Indexed: 06/02/2023]
Abstract
Gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM) and particulate bound mercury (PBM) were measured on the University of Mississippi campus from July 2011 to June 2012. It is believed to be the first time that concentrations of atmospheric mercury species have been documented in northern Mississippi, and at a location with relatively large and sudden swings in population. The mean concentration (±1 SD) of GEM was 1.54±0.32 ng m(-3); levels were lower and generally more stable during the winter (1.48±0.22) and spring (1.46±0.27) compared with the summer (1.56±0.32) and fall (1.63±0.42). Mean concentrations for GOM and PBM were 3.87 pg m(-3) and 4.58 pg m(-3), respectively; levels tended to be highest in the afternoon and lowest in the early morning hours. During the fall and spring academic semesters concentrations and variability of GOM and PBM both increased, possibly from vehicle exhaust. There were moderate negative correlations with wind speed (all species) and humidity (GOM and PBM). Backward air mass trajectory modeling for the ten highest peaks for each mercury species revealed that the majority of these events occurred from air masses that passed through the northern continental US region. Overall, this study illustrates the complexity of temporal fluctuations of airborne mercury species, even in a small town environment.
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Affiliation(s)
- Yi Jiang
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS 38677, USA
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23
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Bu K, Cizdziel JV, Dasher D. Plutonium concentration and (240)Pu/(239)Pu atom ratio in biota collected from Amchitka Island, Alaska: recent measurements using ICP-SFMS. J Environ Radioact 2013; 124:29-36. [PMID: 23639692 DOI: 10.1016/j.jenvrad.2013.03.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [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: 12/28/2012] [Revised: 02/28/2013] [Accepted: 03/06/2013] [Indexed: 06/02/2023]
Abstract
Three underground nuclear tests, including the Unites States' largest, were conducted on Amchitka Island, Alaska. Monitoring of the radiological environment around the island is challenging because of its remote location. In 2008, the Department of Energy (DOE) Office of Legacy Management (LM) became responsible for the long term maintenance and surveillance of the Amchitka site. The first DOE LM environmental survey occurred in 2011 and is part of a cycle of activities that will occur every 5 years. The University of Alaska Fairbanks, a participant in the 2011 study, provided the lichen (Cladonia spp.), freshwater moss (Fontinalis neomexicanus), kelp (Eualaria fistulosa) and horse mussel (Modiolus modiolus) samples from Amchitka Island and Adak Island (a control site). These samples were analyzed for (239)Pu and (240)Pu concentration and (240)Pu/(239)Pu atom ratio using inductively coupled plasma sector field mass spectrometry (ICP-SFMS). Plutonium concentrations and (240)Pu/(239)Pu atom ratios were generally consistent with previous terrestrial and marine studies in the region. The ((239)+)(240)Pu levels (mBq kg(-1), dry weight) ranged from 3.79 to 57.1 for lichen, 167-700 for kelp, 27.9-148 for horse mussel, and 560-573 for moss. Lichen from Adak Island had higher Pu concentrations than Amchitka Island, the difference was likely the result of the higher precipitation at Adak compared to Amchitka. The (240)Pu/(239)Pu atom ratios were significantly higher in marine samples compared to terrestrial and freshwater samples (t-test, p < 0.001); lichen and moss averaged 0.184 ± 0.007, similar to the integrated global fallout ratio, whereas kelp and mussel (soft tissue) averaged 0.226 ± 0.003. These observations provide supporting evidence that a large input of isotopically heavier Pu occurred into the North Pacific Ocean, likely from the Marshall Island high yield nuclear tests, but other potential sources, such as the Kamchatka Peninsula Rybachiy Naval Base and Amchitka Island underground nuclear test site cannot be ruled out.
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Affiliation(s)
- Kaixuan Bu
- Department of Chemistry and Biochemistry, University of Mississippi, University, 116 Taylor Meadows Dr, MS 38677, USA.
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24
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Nowinski P, Hodge VF, Gerstenberger S, Cizdziel JV. Analysis of mercury in rock varnish samples in areas impacted by coal-fired power plants. Environ Pollut 2013; 179:132-137. [PMID: 23669462 DOI: 10.1016/j.envpol.2013.04.011] [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: 12/24/2012] [Revised: 04/04/2013] [Accepted: 04/06/2013] [Indexed: 06/02/2023]
Abstract
Rock varnish is a manganese-iron rich coating that forms on rocks, most often in arid climates. To assess its utility as an environmental monitor of mercury contamination, cold vapor atomic absorption spectrometry (CVAAS) was used for analysis. Samples were collected in the fallout patterns of two coal-fired power plants in southern Nevada: the defunct Mohave Power Plant (MPP) and the operating Reid Gardner Power Plant (RGPP). The resultant Hg concentrations in rock varnishes were plotted as a function of the distance from each power plant. The highest concentrations of Hg occurred at locations that suggest the power plants are the main source of pollutants. In addition, past tracer plume studies carried out at MPP show that the highest tracer concentrations coincide with the highest rock varnish Hg concentrations. However, additional samples are required to further demonstrate that power plants are indeed the sources of mercury in varnishes.
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Affiliation(s)
- Piotr Nowinski
- Clark County Department of Air Quality, 4701 W Russell Road, Suite 200, Las Vegas, NV 89118, USA.
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Cizdziel JV, Dempsey S, Halbrook RS. Preliminary evaluation of the use of homing pigeons as biomonitors of mercury in urban areas of the USA and China. Bull Environ Contam Toxicol 2013; 90:302-307. [PMID: 23229303 DOI: 10.1007/s00128-012-0918-y] [Citation(s) in RCA: 6] [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: 08/10/2012] [Accepted: 12/01/2012] [Indexed: 06/01/2023]
Abstract
Mercury was determined in the tissues (feather, lung, liver, and kidney) of homing pigeons (Columbia livia domestica) from both the USA (Glendora, California and Midland, Texas) and China (Beijing and Chengdu). Among these cities, mercury concentrations were greatest in samples from Beijing, which is known to have relatively high levels of airborne mercury. Among the tissues, levels were highest in the feather, followed by kidney, liver, and lung. There was no significant trend for mercury with pigeon age, weight, or sex, except for mercury with bird weight in the lung of the Beijing samples. Overall, the data adds to the growing body of evidence that the homing pigeon can serve as a useful biomonitor in urban areas.
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Affiliation(s)
- James V Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS 38677, USA.
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Bu K, Cizdziel JV, Reidy L. Analysis of herbal supplements for selected dietary minerals and trace elements by laser ablation- and solution-based ICPMS. Microchem J 2013. [DOI: 10.1016/j.microc.2012.07.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Duke SO, Reddy KN, Bu K, Cizdziel JV. Effects of glyphosate on the mineral content of glyphosate-resistant soybeans (Glycine max). J Agric Food Chem 2012; 60:6764-71. [PMID: 22708739 DOI: 10.1021/jf3014603] [Citation(s) in RCA: 8] [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: 05/27/2023]
Abstract
There are conflicting claims as to whether treatment with glyphosate adversely affects mineral nutrition of glyphosate-resistant (GR) crops. Those who have made claims of adverse effects have argued links between reduced Mn and diseases in these crops. This article describes experiments designed to determine the effects of a recommended rate (0.86 kg ha(-1)) of glyphosate applied once or twice on the mineral content of young and mature leaves, as well as in seeds produced by GR soybeans (Glycine max) in both the greenhouse and field using inductively coupled plasma mass spectrometry (ICP-MS). In the greenhouse, there were no effects of either one application (at 3 weeks after planting, WAP) or two applications (at 3 and 6 WAP) of glyphosate on Ca, Mg, Mn, Zn, Fe, Cu, Sr, Ba, Al, Cd, Cr, Co, or Ni content of young or old leaves sampled at 6, 9, and 12 WAP and in harvested seed. Se concentrations were too low for accurate detection in leaves, but there was also no effect of glyphosate applications on Se in the seeds. In the field study, there were no effects of two applications (at 3 and 6 WAP) of glyphosate on Ca, Mg, Mn, Zn, Fe, Cu, Sr, Ba, Al, Cd, Cr, Co, or Ni content of young or old leaves at either 9 or 12 WAP. There was also no effect on Se in the seeds. There was no difference in yield between control and glyphosate-treated GR soybeans in the field. The results indicate that glyphosate does not influence mineral nutrition of GR soybean at recommended rates for weed management in the field. Furthermore, the field studies confirm the results of greenhouse studies.
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Affiliation(s)
- Stephen O Duke
- USDA , ARS, Natural Product Utilization Research Unit, University, Mississippi 38677, United States
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Cizdziel JV, Jiang Y. Concentrations of gaseous elemental mercury in ambient air within an academic chemistry building. Bull Environ Contam Toxicol 2011; 86:419-422. [PMID: 21290100 DOI: 10.1007/s00128-011-0206-2] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Accepted: 01/24/2011] [Indexed: 05/30/2023]
Abstract
Gaseous elemental mercury (GEM) concentrations were determined within an academic chemistry building by cold vapor atomic fluorescence spectrometry. Concentrations varied depending on the room activity, with night time and weekend levels the lowest and most stable (typically between 10 and 20 ng/m(3)), and daytime weekday levels the highest (averaging about 3-5 times higher). Laboratory air exhibited daytime concentration spikes as high as 1,600 ng/m(3). Office levels were similar to weekend laboratory concentrations, suggesting a general building-wide mercury background. However, concentration spikes suggest GEM levels may be exacerbated by foot traffic which may cause motion-induced wafting from higher concentration areas. Based on current regulations the GEM levels do not present a health hazard.
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Affiliation(s)
- James V Cizdziel
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS 38677, USA.
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Gamage SV, Hodge VF, Cizdziel JV, Lindley K. Determination of Vanadium (IV) and (V) in Southern Nevada Groundwater by Ion Chromatography-Inductively Coupled Plasma Mass Spectrometry~!2009-12-24~!2010-02-10~!2010-05-11~! ACTA ACUST UNITED AC 2010. [DOI: 10.2174/1875038901003010010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Cizdziel JV, Guo C, Steinberg SM, Yu Z, Johannesson KH. Chemical and colloidal analyses of natural seep water collected from the exploratory studies facility inside Yucca Mountain, Nevada, USA. Environ Geochem Health 2008; 30:31-44. [PMID: 17505890 DOI: 10.1007/s10653-007-9105-1] [Citation(s) in RCA: 4] [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: 01/02/2007] [Accepted: 04/03/2007] [Indexed: 05/15/2023]
Abstract
Yucca Mountain is being considered as a geological repository for the USA's spent nuclear fuel and high-level nuclear waste. Numerous groundwater seeps appeared during March 2005 within the exploratory studies facility (ESF), a tunnel excavated in the mountain. Because of the relevance to radionuclide transport and unsaturated zone-modeling studies, we analyzed the seep samples for major anions and cations, rare earth elements, and colloids. Major ion species and elemental concentrations in seep samples reflect interaction of the water with the volcanic rock and secondary calcites. Elemental fractograms from flow-injection field-flow fractionation ICP-MS scans detected Br, Ca, Cl, Cu, Fe, I, Mg, Si, Sr, W, and U at void fractions, suggesting they may be present in the form of dissolved anions. Colloids approximately 10 nm in hydrodynamic diameter, possibly calcite, were also present in the seepage samples. Geochemical calculations indicate, however, these may be an artifact (not present in the groundwater) which arose because of loss of CO2 during sample collection and storage.
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Affiliation(s)
- James V Cizdziel
- Harry Reid Center for Environmental Studies, University of Nevada - Las Vegas, 4505 Maryland Parkway, Las Vegas, NV 89154-4009, USA.
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Cizdziel JV. Determination of lead in blood by laser ablation ICP-TOF-MS analysis of blood spotted and dried on filter paper: a feasibility study. Anal Bioanal Chem 2007; 388:603-11. [PMID: 17396247 DOI: 10.1007/s00216-007-1242-y] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [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: 01/08/2007] [Revised: 02/28/2007] [Accepted: 03/06/2007] [Indexed: 11/30/2022]
Abstract
Screening programs for pediatric lead (Pb) poisoning routinely collect blood by finger stick onto specially designed filter paper (FP) for subsequent laboratory testing. Here, laser ablation inductively coupled plasma time-of-flight mass spectrometry is evaluated as a novel method for the determination of Pb in blood spotted onto FP cards. The method requires no sample pretreatment and may be particularly suitable for rapidly screening a large number of samples. Signal intensity from the ICP-MS strongly correlated (r (2) = 0.996) with Pb target values for five blood cards from a laboratory proficiency testing program. Better precision was obtained by replicate ablation line scans (<15% rsd) compared to a grid of 25 individual ablation spots (>30% rsd). Because <2% of the sample is consumed in the laser ablation analysis, selected samples can also be analyzed by traditional techniques or archived. Lead isotope ratios determined during the same total-Pb analysis appear to be effective for discerning contamination extraneous to the blood sample. Determining that an elevated result was due to contamination may negate the need for retesting with invasive pediatric venipuncture. Some elements monitored along with Pb exhibited signal profiles conducive to potential quantitation (Ca, V, Fe, Cu Zn), whereas others did not (Cr, Mn, Co, Ni, Cd, Hg, Tl, U). Copper, Ca, and V were inversely correlated with Pb (r = -0.89, -0.90, and -0.92, respectively). Scanning electron microscope images revealed surface modality differences between FP spotted with fresh whole blood and reconstituted freeze-dried blood reference material.
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Affiliation(s)
- James V Cizdziel
- Harry Reid Center for Environmental Studies, University of Nevada-Las Vegas, 4505 Maryland Parkway, Las Vegas, NV 89154-4009, USA.
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Cizdziel JV, Hinners TA, Pollard JE, Heithmar EM, Cross CL. Mercury concentrations in fish from Lake Mead, USA, related to fish size, condition, trophic level, location, and consumption risk. Arch Environ Contam Toxicol 2002; 43:309-317. [PMID: 12202927 DOI: 10.1007/s00244-002-1191-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [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
Total mercury (Hg) concentrations were determined in the skeletal muscle of 339 fish collected during the fall of 1998 and spring of 1999 from Lake Mead, USA, the nation's largest human-made reservoir. Five species of fish representing a range of trophic levels and the lake's principal game fishes were studied. Hg generally increased with trophic level and fish size. Median Hg concentrations (ng/g wet mass) were 277 in striped bass, 168 in channel catfish, 160 in largemouth bass, 75 in bluegill, and 8 in blue tilapia. Overall, fish from Las Vegas Bay and Boulder Basin had the lowest Hg concentrations, possibly a result of biodilution in this biologically productive area. In general, fish-mercury advisories might include a warning about consuming fillet from emaciated fish, based on the finding that Hg concentrations in 59 striped bass (captured during a scarce-food season) correlated inversely ( r = -0.89, p < 0.001) with a fish nutritional-status factor. This is consistent with starvation-concentration, whereby Hg in fish muscle is lost at a slower rate than the muscle mass. The median concentration found for 139 striped bass corresponds to a recommended risk-based consumption limit of three 8-oz. (227-g) meals per month for a 70-kg adult. Finally, this paper serves as a useful archive for future research and long-term studies of Hg in Lake Mead fish.
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Affiliation(s)
- J V Cizdziel
- University of Nevada-Las Vegas, Harry Reid Center for Environmental Studies, 4505 Maryland Parkway, Las Vegas, Nevada 89154-4009, USA.
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Abstract
Attic dust and soil samples were collected during the Summer of 1996 and the Spring of 1997 in southern Nevada and southern Utah. Analysis of the samples for radiocesium and plutonium give activity ratios of radiocesium/plutonium that range from 0.7 +/- 0.1 to 27 +/- 2, well below the world-wide fallout ratio of 34 +/- 4 (as of 1 July 1997). This indicates anomalous plutonium throughout the region, including areas to the south of the Nevada Test Site (NTS), generally believed to have received only world-wide fallout. Safety tests and above-ground detonations that resulted in incomplete fission, conducted at the NTS during the 1950's and 1960's, are likely sources of this excess plutonium.
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Affiliation(s)
- J V Cizdziel
- Environmental Science and Health Graduate Program, University of Nevada, Reno 89557-0187, USA.
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