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Cadmium Lacey Brandt

Cadmium Lacey Brandt. Cadmium properties. Transition metal Solid Silvery grey Oxidation state- +2, +1 Atomic weight- 112.4g/mol Density-8.65g/cm³. No reaction with water Malleable Ductile. History and production. 1817- Cd discovered- impure ZnCo3- color and heat

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Cadmium Lacey Brandt

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  1. Cadmium Lacey Brandt

  2. Cadmium properties • Transition metal • Solid • Silvery grey • Oxidation state- +2, +1 • Atomic weight- 112.4g/mol • Density-8.65g/cm³ • No reaction with water • Malleable • Ductile

  3. History and production • 1817- Cd discovered- impure ZnCo3- color and heat • 1850- Cadmium pigments- yellow, red • 1899- NiCd rechargeable battery • 1907- production in the united states • 1900’s- corrosion-protection steel coating • After 1945- wide spread use Freidrich Stromeyer German chemist

  4. current use • Ni-Cd batteries • protective coatings • pigments • stabilizer- PVC • alloys • pesticides

  5. Cadmium isotopes

  6. CADMIUM SALTS- different solubility, toxic levels • CdH₂ • CdF₂ • CdCl₂ • CdBr₂ • CdI₂ • CdO • CdS • CdSe • CdTe • Cd₃N₂

  7. CADMIUM ENTRY INTO ENVIRONMENT • weathering • erosion • river runoff • diatom deposition • occurs naturally

  8. Cadmium enters and accumulates in many marine organisms • Food consumption • Respiration • Filtration

  9. TOXICITY TO MARINE ANIMALS • Salinity and Cd toxicity • Inversely proportional • Cl binds with Cd • Free Cd toxic

  10. Trophic transfer • [Cd ]of the water is not indication • of food safety • Fish growth affected

  11. Penaeid shrimp Penaeu japonicus Increased tolerance with development nauplii 48h LC50=124ug/L Zoea 96 LC50=10-30ug/L Post-larvae 96 LC50= 200-3500ug/L Juvenile 96LC50=5500ug/L Decreased osmoregulation

  12. Chronic protracted toxicity test • Mysidopsis bahia • 17 day life cycle test • 10.6 ug/L @ 20 ⁰/₀₀ • Δ Breeding cycle • Δ # of young released • Sensitive crustacean LC50 ~ 15

  13. Eastern oyster- Crassostrea virginica • Physiological effects • intracellular localization • Gills- mitochondria-> Respiration-> metabolism • Hepatopancreas- lysosomes -> lysosome damage

  14. A DEEPER LOOK….. Mutagenic - DNA Clastogenic- chromosomes Carcinogenic-cancer Teratogenic-birth defects

  15. GENOTOXICITY • Cd • Break DNA directly • Break DNA indirectly • Oxidative stress- free radicals • Inhibits glutathione ROS scavenger • Response= DNA breakage/ recovery • Cd impairs DNA repair- compete with zinc

  16. MECHANISMS OF DETOXIFICATION • Metallothioneins (MT) • low mw proteins • cytosol • saturation- bind to critical sites • Sequestering- • Vesicles- lysosomes, other structures • Saturation-> lysosome damage • FOUNDRY COVE/ SOUTH COVE STUDY • oligochaete Limnodrilus sp. Used both mechanisms • MTs transfer to lysosomes

  17. Bambang, Y., Charmantier, G., Thuet, P., and Trilles, J.P. (September 1995). Effects of cadmium on survival and osmoregulation on various developmental stages of the shrimp Penaeus japonicus (crustacea: Decapoda). Marine Biology, 123 (3), 443-450. Binary compounds. Retrieved May 3, 2008, from http://www.webelements.com/webelements/elements/text/Cd/comp.html Cadmium. Retrieved May 3, 2008, from http://www.cadmium.org Engel, D.W., Fowler, B.A. (February 1979). Factors influencing Cadmium accumulation and its toxicity to marine organisms. Environmental health perspectives, 28, 81-88 Mechanisms of Metal Detoxification. Retrieved May 3, 2008, from http://life.bio.sunysb.edu/marinebio/fc.8.detoxification.html Nimmo, D.R., Rigby, R.A., Sheppard, J.M. (January 1978). The acute and chronic effects of cadmium on the estuarine mysid. Mysidopsis bahia. Bulletin of Environmental Contamination and Toxicology, 19(1) 80-85. Pan Pesticides database. Retrieved May 3, 2008, from http://www.pesticideinfo.org/Detail_Chemical.jsp?Rec_Id=PC33703#Ecotoxicology Pruski, A.M., Dixon, D.R. (2002). Effects of cadmium on nuclear integrity and DNA repair efficiency in the gill cells of Mytilus edulis L. Aquatic Toxicology, 57, 127-137. Risso-de Faverney, C., Devaux, A., Lafaurie, M., Girard, J.P., Bailly, B., and Rahmani, R.(2001) Cadmium induces apoptosis and genotoxicity in rainbow trout hepatocytes through generation of reactive oxygen species. Aquatic Toxicology, 53, 65-76. Ruangsomboon, S., Wongrat, L. (June 2006). Bioaccumulation of cadmium in an experimental aquatic food chain involving phytoplankton(Chlorella vulgaris), zooplankton (Moina macrocopa), and the predatory catfish Clarias macrocephalus x C. gariepinus. Aquatic Toxicology, 78 (1), 15-20. Sokolova, I.M., Ringwood, A.H., and Johnson, C. (September 2005). Tissue-specific accumulation of cadmium in subcellular compartments of eastern oysters Crassostrea virginica Gmelin (Bivalvia: Ostreidae). Aquatic Toxicology, 74 (3), 218-228. Wikipedia. Retrieved May 3, 2008, from http://en.wikipedia.org

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