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Copper

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					                   wikipedia.com




Copper

         Aaron Malone-Stratton
              Biology 564
             May 1, 2008
Physical and Chemical
Properties
• Atomic Number - 29   • Density
• MW = 63.546            – 8.96 g cm-1
• Solid                • Melting Point
• Hydrophilic            – 1357.77 K

• Ductile and good     • Oxidation States
  conductivity           – +1, +2, +3, +4

• Heat conductor
Isotopes
• Natural             • Radio isotopes
  –   63Cu   , 65Cu     – Multiple isotopes
                           • Short half-life
                           • 31s - 2.5d
                        – Used in research
Uses of Copper
•   Antimicrobial surfaces   • Important in redox
•   Coinage                    enzymes
•   Cookware                 • Important ion in
•   Wire and electronics       haemocyanin
•   Piping
•   Metal alloys
    – Over 400 types
• Biocides
    – Fungi and algae
Mode of Entry - Environment
• Mining/refinement        • Decaying plants
  runoff                   • Volcanoes
• Industrial smoke
                           • Forest fires
• Animal feed
• Brake dust
• E-waste
• Waste water through
  degrading pipes
• Biocides
   – Agricultural Poison
   – Water Purification
      • CuS, Cu2S

                                               flickr.com
Reactivity and Chemical
Speciation
• React with air not water (pure water)
• Reactive with ammonia/oxygen and
  chloride/oxygen solutions
• Copper oxide Cu2O
   – 4Cu(s) + O2(g)  2Cu2O(s)




   nyctourist.com        indospectrum.com



• Many other compounds (www.webelements.com)
Mode of Entry - Organism
• Gills
• Digestive tract
Mode Of Toxic Interaction
• Compete with Na+ for Na+/Ca2+
  Exchangers
  – Intestine
  – Gills




                                  lib.mcg.edu
Toxicity to Aquatic Life and
Toxic Effects
• Osmoregulation
  – Swelling and disruption of epithelial cell of gill
  – Kidney and liver damage
• Neurological/
  developmental
  disorders
  – Cu binds instead
  of other metals
  – Binding sulfhydryl
    of proteins                                    De Boeck et al. 2007

     • Enzyme activation/
       deactivation
Formation of Hydroxyl Radicals
• Cu2+, H2O2 (hydrogen peroxide),*O2 (superoxide)
   – Haber-Wiess reaction and Fenton reaction
       • Cu2+ + *O2-  Cu+ + O2
       • Cu+ + H2O2  Cu2+ + OH- + *OH
• Free radicals cause damage to cells
                                          ppb by weight
                               Seawater               3
Toxicity                       Stream                 6
                               Human              1000

• EPA Limit
  – 1.3 ppm for drinking water
• Mugil cephalus (teleost)
  – LC50 96h 5 mg/L
  – 10 mg/L = 100% mortality
• Squalus acanthias (elasmobranch)
  – LC50 96h 800-1000 ug/L
• Cancer magister (crustacean)
  – LC50 96h 0.1 mg/L
Metabolism and Breakdown
• 15% used in diet
  – Enzyme Activity
• 85% sequestered (liver) or excreted
Glutathione
                                       wikipedia.com


• High abundance in cells (liver)
• Reduced form (GSH) 90% abundance
  – Reacts with Cu to form GS-Cu
  – H+ donated to reactive oxygen species
  – Sequesters free copper
• Oxidized form (GSSG) 10% abundance
  – GSSGGSH (glutathione reductase)
Metallothionein (MT)
• Metal induces production of protein
  – Transport of metals
     • 2 cystine-rich areas (metal binding site)
     • Releases bound metals upon oxidation of
       cystine residues
  – Bind excess metal
     • Excrete or storage???
• Transfer of Cu from GS to MT
  – Via GS-Cu-MT complex
Menkens ATPase Pump
• Copper induced activity
• Most excreted through bile not urine
• Mechanism of acquiring metal unknown
  – Low free copper in cell
Defense
• Sodium in diet - reduce binding to gills




                         lib.mcg.edu
References
•   copper.org
•   webelements.com
•   Copper - Environmental Literacy Council
    (http://www.enviroliteracy.org/article.php/1029.html)
•   Agency for Toxic Substances and Disease Registry. Copper. CAS # 7440-
    50-8. 2004.
•   Zyadah M.A., Abdel-Baky T.E. (2000) Toxicity and Bioaccumulation of
    Copper, Zinc, and Cadmium in Some Aquatic Organisms. Bull. Environ.
    Contam. Toxicol. 64:740-747
•   De Boeck G., Grosell M., Wood C. (2001) Sensitivity of the spiny dogfih
    (Squalus acanthias ) to waterborne silver exposure. Aquatic Toxicology 54:261-
    275
•   Kang J. (2006) Metallothionein Redox Cycle and Function. Experimantal Biology
    and Medicine 231: 1459-1467
•   Koppenol W. H. (2001) The Haber-Weiss Cycle - 70 years later. Redox Report
    Vol. 6 229-234
•   Mason A.Z., Jenkins K.D. (1995) Metal Detoxification in Aquatic Organisms.
    Metal Speciation and Bioavailability in Aquatic Systems. 479-608
References
•   Mason A., Moeller R., Thrippleton K., Lloyd D. (2007) Use of stable isotopically
    enriched proteins and directly coupled high-performance liquid chromatography
    inductively coupled plasma mass spectrometry for quantitatively monitoring the
    transfer of metals between proteins. Analytical Biochemistry 396: 87-104
•   Wijmenga C., Klomp L. W. J. (2004) Molecular regulation of copper excretion in
    the liver. Proceedings of the Nutrition Society. 63: 31-39
•   Rauch H., Wells A.J. (1989) Hepatic metallothionein turnover in toxic milk
    mutant mice. FASEB Journal. 3:3
•   Klassen C., Choudhuri S., McKim Jr. J.,Lehman-McKeeman L., Kershaw W.
    (1994) In Vitro and In Vivo Studies on the Degradation of Metallothionein.
    Environmental Health Perspectives. 102
•   Dameron C., Harrison M. (1998) Mechanisms for protection against copper
    toxicity. Am. J. Clin. Nutr. 67(suppl) 1091S-7S
•   Independent Contractor of INCA (1989) Final Report INCA Project No. 223
    The Biological Importance of Copper, A Literature Review.

				
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