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Tamez C, Molina-Hernandez M, Medina-Velo IA, Cota-Ruiz K, Hernandez-Viezcas JA, Gardea-Torresdey J. Long-term assessment of nano and bulk copper compound exposure in sugarcane (Saccharum officinarum). Sci Total Environ 2020; 718:137318. [PMID: 32088484 DOI: 10.1016/j.scitotenv.2020.137318] [Citation(s) in RCA: 4] [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: 12/02/2019] [Revised: 02/11/2020] [Accepted: 02/13/2020] [Indexed: 06/10/2023]
Abstract
As interest in the use of copper-based nanomaterials in agriculture continue to increase, research into their exposure effects must expand from short-term, high exposure studies to long-term studies at realistic concentrations. Long-term studies can better elucidate the implications of copper nanomaterial exposure by allowing plants to mature and adapt to higher copper concentrations. In this study, sugarcane plants were grown to maturity in large nursery pots using soils amended with one of the following treatments: Kocide 3000 (Cu(OH)2), a nano-sized CuO (nCuO), a bulk-sized CuO (bCuO), copper metal nanoparticles (Cu NP), or CuCl2 at 20, 40, and 60 mg kg-1. After tissue harvesting, copper content in plant tissues, including pressed cane juice, were determined. Chlorophyll content and the activity of reactive oxygen species (ROS) related enzymes, in root tissues, were measured as an indicator of plant health. Elemental analysis revealed significant changes in root copper concentrations only upon application of the highest levels of Kocide 3000, nCuO, and Cu NP. However, translocation of copper to leaf tissues displayed consistent increases with added copper over controls. Plants treated with Kocide 3000 at 60 mg kg-1 experienced a significant 31% decrease in cane juice yield; copper concentrations in the pressed juice of plants treated with: Kocide 3000 at 20 and 60 mg kg-1, nCuO at 20 and 60 mg kg-1, bCuO at 20 mg kg-1, CuCl2 at 40 mg kg-1, and Cu NP increased by at least 58%. Chlorophyll content remained comparable to controls, and there was a significant 50 to 68% decrease in superoxide dismutase (SOD) activity in plants treated with nCuO, bCuO, Cu NP, and CuCl2. The results indicate that sugarcane plants exposed to the selected copper-based treatments were not adversely affected.
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Affiliation(s)
- C Tamez
- Environmental Science and Engineering PhD. Program, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States; Department of Chemistry, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States; University of California Center for Environmental Implications of Nanotechnology (UC CEIN), The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States
| | - M Molina-Hernandez
- Environmental Science Program, Department of Geological Sciences, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States
| | - I A Medina-Velo
- Department of Natural Sciences, Western New Mexico University, 1000 West College Ave., Silver City, NM 88062, United States
| | - K Cota-Ruiz
- Department of Chemistry, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States
| | - J A Hernandez-Viezcas
- Department of Chemistry, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States
| | - J Gardea-Torresdey
- Environmental Science and Engineering PhD. Program, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States; Department of Chemistry, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States; University of California Center for Environmental Implications of Nanotechnology (UC CEIN), The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States.
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Tamez C, Morelius EW, Hernandez-Viezcas JA, Peralta-Videa JR, Gardea-Torresdey J. Biochemical and physiological effects of copper compounds/nanoparticles on sugarcane (Saccharum officinarum). Sci Total Environ 2019; 649:554-562. [PMID: 30176466 DOI: 10.1016/j.scitotenv.2018.08.337] [Citation(s) in RCA: 7] [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: 07/24/2018] [Revised: 08/24/2018] [Accepted: 08/24/2018] [Indexed: 06/08/2023]
Abstract
The widespread use of copper based nanomaterials has been accompanied by an increasing interest in understanding their potential risks. It is essential to understand the effects of these nanoparticles on edible crops by performing long-term experiments at relevant exposure concentrations. Sugarcane is the source of 70% of the world's sugar supply and the widespread use of refined sugar and the consumption of raw sugarcane can provide a route for nanoparticles to enter the food supply. In order to evaluate the biochemical and physiological effects of copper nanoparticle exposure, sugarcane was grown for one year in soil amended with 20, 40, and 60 mg/kg of Kocide 3000 (a copper based fungicide), copper metal nanoparticles, micro-sized CuO, and CuCl2. The results show that stress indicators such as catalase and ascorbic peroxidase enzymatic activity in the sugarcane plant were activated by all the copper based materials at different concentrations. Sugarcane plants exposed to nearly all copper treatments showed dosage dependent increases in copper concentrations in root tissues. Translocation of copper to aerial tissues was minimal, with copper concentrations not being significantly different from controls. In addition, Chlorophyll A content was higher in plants treated with Kocide 3000 at 20 and 60 mg/kg, μCuO at 20 mg/kg, and CuCl2 at 20 and 60 mg/kg. To our knowledge, this is the first report on the effects of nano-copper compounds in sugarcane crop.
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Affiliation(s)
- C Tamez
- Environmental Science and Engineering PhD. Program, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States; University of California Center for Environmental Implications of Nanotechnology (UC CEIN), The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States
| | - E W Morelius
- Environmental Science and Engineering PhD. Program, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States
| | - J A Hernandez-Viezcas
- Department of Chemistry, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States
| | - J R Peralta-Videa
- Environmental Science and Engineering PhD. Program, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States; Department of Chemistry, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States; University of California Center for Environmental Implications of Nanotechnology (UC CEIN), The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States
| | - J Gardea-Torresdey
- Environmental Science and Engineering PhD. Program, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States; Department of Chemistry, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States; University of California Center for Environmental Implications of Nanotechnology (UC CEIN), The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States.
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Hernandez-Viezcas J, Castillo-Michel H, Servin A, Peralta-Videa J, Gardea-Torresdey J. Spectroscopic verification of zinc absorption and distribution in the desert plant Prosopis juliflora-velutina (velvet mesquite) treated with ZnO nanoparticles. Chem Eng J 2011; 170:346-352. [PMID: 22820414 PMCID: PMC3399254 DOI: 10.1016/j.cej.2010.12.021] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The impact of metal nanoparticles (NPs) on biological systems, especially plants, is still not well understood. The aim of this research was to determine the effects of zinc oxide (ZnO) NPs in velvet mesquite (Prosopis juliflora-velutina). Mesquite seedlings were grown for 15 days in hydroponics with ZnO NPs (10 nm) at concentrations varying from 500 to 4000 mg L(-1). Zinc concentrations in roots, stems and leaves were determined by inductively coupled plasma optical emission spectroscopy (ICP-OES). Plant stress was examined by the specific activity of catalase (CAT) and ascorbate peroxidase (APOX); while the biotransformation of ZnO NPs and Zn distribution in tissues was determined by X-ray absorption spectroscopy (XAS) and micro X-ray fluorescence (μXRF), respectively. ICP-OES results showed that Zn concentrations in tissues (2102 ± 87, 1135 ± 56, and 628 ± 130 mg kg(-1) d wt in roots, stems, and leaves, respectively) were found at 2000 mg ZnO NPs L(-1). Stress tests showed that ZnO NPs increased CAT in roots, stems, and leaves, while APOX increased only in stems and leaves. XANES spectra demonstrated that ZnO NPs were not present in mesquite tissues, while Zn was found as Zn(II), resembling the spectra of Zn(NO(3))(2). The μXRF analysis confirmed the presence of Zn in the vascular system of roots and leaves in ZnO NP treated plants.
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Affiliation(s)
- J.A. Hernandez-Viezcas
- Chemistry Department, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States
| | - H. Castillo-Michel
- Environmental Science and Engineering PhD Program, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States
| | - A.D. Servin
- Chemistry Department, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States
| | - J.R. Peralta-Videa
- Chemistry Department, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States
| | - J.L. Gardea-Torresdey
- Chemistry Department, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States
- Environmental Science and Engineering PhD Program, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States
- Corresponding author at: Chemistry Department, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States. Tel.: +1 915 747 5359. (J.L. Gardea-Torresdey)
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Del Toro I, Floyd K, Gardea-Torresdey J, Borrok D. Heavy metal distribution and bioaccumulation in Chihuahuan Desert Rough Harvester ant (Pogonomyrmex rugosus) populations. Environ Pollut 2010; 158:1281-1287. [PMID: 20189272 DOI: 10.1016/j.envpol.2010.01.024] [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: 09/01/2009] [Revised: 01/20/2010] [Accepted: 01/22/2010] [Indexed: 05/28/2023]
Abstract
Heavy metal contamination can negatively impact arid ecosystems; however a thorough examination of bioaccumulation patterns has not been completed. We analyzed the distribution of As, Cd, Cu, Pb and Zn in soils, seeds and ant (Pogonomyrmex rugosus) populations of the Chihuahuan Desert near El Paso, TX, USA. Concentrations of As, Cd, Cu, and Pb in soils, seeds and ants declined as a function of distance from a now inactive Cu and Pb smelter and all five metals bioaccumulated in the granivorous ants. The average bioaccumulation factors for the metals from seeds to ants ranged from 1.04x (As) to 8.12x (Cd). The findings show bioaccumulation trends in linked trophic levels in an arid ecosystem and further investigation should focus on the impacts of heavy metal contamination at the community level.
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Affiliation(s)
- I Del Toro
- Department of Organismic and Evolutionary Biology, University of Massachusetts at Amherst, 611 N. Pleasant Street Amherst, MA 01003, USA.
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Parsons J, Luna C, Botez C, Elizalde J, Gardea-Torresdey J. Microwave Assisted Synthesis of Iron(III) Oxyhydroxides/Oxides Characterized Using Transmission Electron Microscopy, X-ray Diffraction, and X-ray Absorption Spectroscopy. J Phys Chem Solids 2009; 70:555-560. [PMID: 20161181 PMCID: PMC2726966 DOI: 10.1016/j.jpcs.2008.12.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Microwave assisted synthesis of iron oxide/oxyhydroxide nanophases was conducted using iron(III) chloride titrated with sodium hydroxide at seven different temperatures from 100 degrees C to 250 degrees C with pulsed microwaves. From the XRD results, it was determined that there were two different phases synthesized during the reactions which were temperature dependent. At the lower temperatures, 100 degrees C and 125 degrees C, it was determined that an iron oxyhydroxide chloride was synthesized. Whereas, at higher temperatures, at 150 degrees C and above, iron(III) oxide was synthesized. From the XRD, we also determined the FWHM and the average size of the nanoparticles using the Scherrer equation. The average size of the nanoparticles synthesized using the experimental conditions were 17, 21, 12, 22, 26, 33, 28 nm, respectively for the reactions from 100 degrees C to 250 degrees C. The particles also had low anisotropy indicating spherical nanoparticles, which was later confirmed using TEM. Finally, XAS studies show that the iron present in the nanophase was present as iron(III) coordinated to six oxygen atoms in the first coordination shell. The higher coordination shells also conform very closely to the ideal or bulk crystal structures.
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Affiliation(s)
- J.G. Parsons
- University of Texas at El Paso Department of Chemistry, 500 W University Ave El Paso TX 79986
| | - C. Luna
- University of Texas at El Paso Environmental Science and Engineering PhD program, 500 W University Ave. El Paso TX 79968
| | - C.E. Botez
- University of Texas at El Paso Department of Physics, 500 W University Ave El Paso TX 79986
| | - J. Elizalde
- University of Texas at El Paso Department of Physics, 500 W University Ave El Paso TX 79986
| | - J.L. Gardea-Torresdey
- University of Texas at El Paso Department of Chemistry, 500 W University Ave El Paso TX 79986
- University of Texas at El Paso Environmental Science and Engineering PhD program, 500 W University Ave. El Paso TX 79968
- Corresponding Author: , phone: (915)747-5359, fax: (915)-747-5847
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Parsons J, Lopez M, Peralta-Videa J, Gardea-Torresdey J. Determination of arsenic(III) and arsenic(V) binding to microwave assisted hydrothermal synthetically prepared Fe3O4, Mn3O4, and MnFe2O4 nanoadsorbents. Microchem J 2009. [DOI: 10.1016/j.microc.2008.08.012] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Parsons J, Peralta-Videa J, Gardea-Torresdey J. Chapter 21 Use of plants in biotechnology: Synthesis of metal nanoparticles by inactivated plant tissues, plant extracts, and living plants. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s1474-8177(07)05021-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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Sawalha M, Gardea-Torresdey J, Parsons J, Saupe G, Peralta-Videa J. Determination of adsorption and speciation of chromium species by saltbush (Atriplex canescens) biomass using a combination of XAS and ICP–OES. Microchem J 2005. [DOI: 10.1016/j.microc.2005.01.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Montero Cabrera M, Colmenero Sujo L, Villalba L, de la Cruz Gandara S, Sáenz Peinado J, Rentería Villalobos M, Sanín Aguirre L, Herrera Peraza E, Lopez J, Gardea-Torresdey J. Rn-222 air concentrations in Chihuahua State (Mexico) dwellings and in the U.S./Mexico border. Microchem J 2005. [DOI: 10.1016/j.microc.2005.01.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Cano-Aguilera I, Haque N, Morrison G, Aguilera-Alvarado A, Gutiérrez M, Gardea-Torresdey J, de la Rosa G. Use of hydride generation-atomic absorption spectrometry to determine the effects of hard ions, iron salts and humic substances on arsenic sorption to sorghum biomass. Microchem J 2005. [DOI: 10.1016/j.microc.2005.01.014] [Citation(s) in RCA: 13] [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: 10/25/2022]
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Peralta-Videa J, de la Rosa G, Gonzalez J, Gardea-Torresdey J. Effects of the growth stage on the heavy metal tolerance of alfalfa plants. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/s1093-0191(03)00040-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Parsons J, Gardea-Torresdey J, Tiemann K, Gamez G. Investigation of trace level binding of PtCl6 and PtCl4 to alfalfa biomass (Medicago sativa) using Zeeman graphite furnace atomic absorption spectrometry. Anal Chim Acta 2003. [DOI: 10.1016/s0003-2670(02)01506-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Gardea-Torresdey J, Hejazi M, Tiemann K, Parsons JG, Duarte-Gardea M, Henning J. Use of hop (Humulus lupulus) agricultural by-products for the reduction of aqueous lead(II) environmental health hazards. J Hazard Mater 2002; 91:95-112. [PMID: 11900908 DOI: 10.1016/s0304-3894(01)00363-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The agricultural by-products of the hop plant (Humulus lupulus L.) were investigated to determine their potential for use in the removal of heavy lead(II) ions from contaminated aqueous solutions. Separate batch laboratory experiments were performed to establish the optimal binding pH, time exposures, and capacity of the metal adsorption for lead(II) ions by dried and ground hop leaves and stems biomass. Results from these studies have shown a pH dependent binding trend from pH 2-6, with optimum binding occurring around pH 5.0. Time dependency experiments showed a rapid adsorption of lead(II) ions within the first 5 min of contact. Binding capacity experiments demonstrated that 74.2mg of lead(II) were bound per gram of leaf biomass. Similarly overall capacity was seen for the leaves and stems. Desorption of 99% of the bound lead(II) ions was achieved by exposing the metal laden biomass to 0.5M sodium citrate. Further experiments were performed with silica-immobilized hop tissues to determine the lead(II) binding ability under flow conditions. Comparison studies were performed with ion-exchange resins to evaluate the binding ability and to gain further insight into the metal binding mechanism. X-ray absorption spectroscopy experiments were also utilized to gain further insight into the possible lead(II) binding mechanism by the hop plant tissue. Results from these studies indicate that carboxyl ligands are involved in the binding of lead(II) from aqueous solution. These findings show that the use of hop agricultural waste products may be a viable alternative, for the removal and recovery of aqueous lead(II) ions from contaminated waters.
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Affiliation(s)
- J Gardea-Torresdey
- Department of Chemistry and Environmental Science and Engineering, The University of Texas at El Paso, El Paso, TX 79968-0513, USA.
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Tiemann K, Gamez G, Dokken K, Parsons J, Gardea-Torresdey J. Chemical modification and X-ray absorption studies for lead(II) binding by Medicago sativa (alfalfa) biomass. Microchem J 2002. [DOI: 10.1016/s0026-265x(02)00021-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Parsons J, Hejazi M, Tiemann K, Henning J, Gardea-Torresdey J. An XAS study of the binding of copper(II), zinc(II), chromium(III) and chromium(VI) to hops biomass. Microchem J 2002. [DOI: 10.1016/s0026-265x(02)00013-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Gardea-Torresdey J, Tiemann K, Parsons J, Gamez G, Herrera I, Jose-Yacaman M. XAS investigations into the mechanism(s) of Au(III) binding and reduction by alfalfa biomass. Microchem J 2002. [DOI: 10.1016/s0026-265x(02)00011-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Tiemann K, Rascon A, Gamez G, Parsons J, Baig T, Cano-Aguilera I, Gardea-Torresdey J. Heavy metal binding by inactivated tissues of Solanum elaeagnifolium: chemical and subsequent XAS studies. Microchem J 2002. [DOI: 10.1016/s0026-265x(02)00005-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Li WW, Orquiz R, Garcia JH, Espino TT, Pingitore NE, Gardea-Torresdey J, Chow J, Watson JG. Analysis of temporal and spatial dichotomous PM air samples in the El Paso-Cd. Juarez air quality basin. J Air Waste Manag Assoc 2001; 51:1551-1560. [PMID: 11720102 DOI: 10.1080/10473289.2001.10464377] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [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
This paper presents and discusses the results obtained from the gravimetric and chemical analyses of the 24-hr average dichotomous samples collected from five sites in the El Paso-Cd. Juarez air quality basin between August 1999 and March 2000. Gravimetric analysis was performed to determine the temporal and spatial variations of PM2.5 (particulate matter less than 2.5 microm in diameter) and PM25-10 (particulate matter less than 10 pm but greater than 2.5 microm in diameter) mass concentrations. The results indicate that approximately 25% of the PM10 (i.e., PM25 + PM25-10) concentration is composed of PM2.5. Concurrent measurements of hourly PM concentrations and wind speed showed strong diurnal patterns of the regional PM pollution. Results of X-ray fluorescence (XRF) elemental analyses were compared to similar but limited studies performed by the Texas Natural Resource Conservation Commission (TNRCC) in 1990 and 1997. Major elements from geologic sources-Al, Si, Ca, Na, K, Fe, and Ti-accounted for 35% of the total mass concentrations in the PM2.5-10 fraction, indicating that geologic sources in the area are the dominant PM sources. Levels of toxic trace elements, mainly considered as products of anthropogenic activities, have decreased significantly from those observed in 1990 and 1997.
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Affiliation(s)
- W W Li
- Department of Civil Engineering, University of Texas at El Paso, USA.
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Affiliation(s)
- G A Eiceman
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces 88003-0001, USA
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Abstract
This review of the fundamental developments in gas chromatography (GC) includes articles published from 1996 and 1997 and an occasional citation prior to 1996. The literature was reviewed principally using CA Selects for Gas Chromatography from Chemical Abstracts Service, and some significant articles from late 1997 may be missing from the review. In addition, the online SciSearch Database (Institute for Scientific Information) capability was used to abstract review articles or books. As with the prior recent reviews, emphasis has been given to the identification and discussion of selected developments, rather than a presentation of a comprehensive literature search, now available widely through computer-based resources. During the last two years, several themes emerged from a review of the literature. Multidimensional gas chromatography has undergone transformation encompassing a broad range of activity, including attempts to establish methods using chromatographic principles rather than a totally empirical approach. Another trend noted was a comparatively large effort in chromatographic theory through modeling efforts; these presumably became resurgent with inexpensive and powerful computing tools. Finally, an impressive level of activity was noted through the themes highlighted in this review, and this was particularly true with detectors and field instruments.
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Affiliation(s)
- G A Eiceman
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces 88003, USA
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Core RJ, Henning JA, Gardea-Torresdey J, Mostafavi R. Quantitative comparison of volatile compounds among sevenMedicago spp. accessions. J Chem Ecol 1996; 22:1621-7. [DOI: 10.1007/bf02272402] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/1995] [Accepted: 04/23/1996] [Indexed: 11/29/2022]
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