Zinc
JESSICA YOUNG
Structure & Properties
 Zn
 Atomic number: 30
 5 Stable isotopes
 Zn64, Zn66, Zn67, Zn68, Zn70
 Many radio isotopes
 Zn65, Zn72
 Exists in oxidation states
 Zn, Zn1+, Zn2+
 Also found in many compounds
 ZnO, ZnCl2, ZnS, and ZnSO4
 Relatively long half life (4.3 X 1018 years)
Uses & Applications
 Oxidated form (Zn2+) occurs naturally in minerals
in the earth’s crust (70 mg/kg)
 Anthropogenic sources

Smelting

used to protect against corrosion
Batteries
 Brass & Bronze manufacturing
 Brakes and car exhaust found to be leading cause of zinc
pollution in Sao Paulo, Brazil study

Uses & Applications
 Applications of zinc compounds
 Herbicides, medical and dental products, household
items (makeup, shampoo, sunscreen)
Zinc in Aquatic Environments
 How it gets there…
 Industrial & urban runoff
 Cations, zinc-inorganic coumpoudns, zinc-organic
compouds
 Zinc ions have a low mobility in sediment and are
readily taken up by plants and animals
 Bioconcentration factors estimated to be 1000 and
2000 for freshwater and marine fish, respectively
Properties in water
 As a cation, it is non soluble in water and is
partitioned into sediment by adsorption onto organic
molecules
 Other common forms are much more soluble


ZnCl2
ZnSO4
 Other solubility factors
 Temperature
 pH
 Mineral composition of water
Necessity & Toxicity
 Zinc is an essential micronutrient found in most
foods; absorbed through gastrointestinal tract

Necessary for enzyme function
 Miners exposed to acute high levels of zinc oxide in
the air experienced respiratory problems
 Interference with absorption of copper and iron
 Effects on cardiovascular, respiratory, and immune systems
 Low leves of HDL
 Stimulated production of amylase and lipase by pancreas
 One incident of human fatality attributed to zinc overdose
Zinc at the Colorado Lagoon
 33.18 mg/ kg in site 5 sediment sample
 35.19 mg/kg in site 8 clam tissue
 CO Lagoon clams contains 16 mg/ pound
 Recommended Daily Allowance is 8-11 mg/ day
 Tolerable Upper Limit is 40 mg/ day
Detoxification
 Metallothionine (MT)
 Cysteine rich proteins found in Golgi
 Found to play key role in uptake, regulation, and distribution
of zinc in organisms
 Zinc is efficiently regulated in mammals and excess
zinc can be excreted via nephridial system
References
EPA; 2005; Toxicological Review of Zinc and Compounds
http://www.epa.gov/iris/toxreviews/0426tr.pdf
Gioia, S., Weiss, D., Coles, B., Arnold, T., Babinski, M.; 2008; Accurate and Precise
Zinc Isotope Ratio Measurements in Urban Aerosols; Analytical Chemistry; v. 80
(24); p. 9776-9780 http://pubs.acs.org/doi/pdf/10.1021/ac8019587
Skidmore, J. F.; 1964; Toxicity of Zinc Compounds to Aquatic Animals, with Special
Reference to Fish; The Quarterly Review of Biology; V. 39 (3); p. 227-248
http://www.jstor.org/stable/2820034
US Dept of Health and Human Services, Agency for Toxic Substances and Disease
Registry; 2005; Toxicological Profile for Zinc
http://www.atsdr.cdc.gov/ToxProfiles/tp60.pdf
National Institutes of Health, Office of Dietary Supplements
http://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/
Sigel, Astrid; Sigel, Helmut; Sigel, Roland K. O.; Metallothionines and Related
Chelators; Metal Ions in Life Sciences; v. 5;
http://www.springer.com/chemistry/inorganic+chemistry/book/978-1-84755899-2?detailsPage=reviews
Zinc Hazards to Fish, Wildlife, and Invertebrates: A Synoptic Review
http://www.pwrc.usgs.gov/infobase/eisler/chr_26_zinc.pdf