mercury - Mercury A element that is liquid at room...

Info iconThis preview shows pages 1–13. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Mercury A element that is liquid at room temperature but can be in a solid, liquid or gaseous state – only metal liquid at room temperature. Applications of Mercury include 1) Thermometers 2) Industrial production of NaOH and Chlorine gas. 3) Fluorescent tubes 4) Batteries 5) Barometers 6) Switches
Background image of page 2
The Mercury Cycle FEMS Microbiology Reviews 11 (1993) 297 – 316 G.M. Gadd
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Problems with Mercury Pollution Mercury is persistent in the environment Mercury bio-accumulates Causes health problems in higher organisms because of bio-accumulation Mercury is associated with many human health problems Causes developmental malformations Causes neurological problems
Background image of page 4
Sources of Mercury Natural Mercury naturally in earth’s crust Hg 0 Volcanic Explosions Hg 0 Natural Gas Hg 0 Anthropogenic Industrial Combustion (eg. Coal) Cinnabar (HgS) Industrial processes Mining Agricultural Sources Hg +2
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Sources of Mercury From industrial manufacturing plants such as those that produce acetaldehyde, NaOH, Cl 2 Human activities, such as the deposition of sludge onto agricultural fields.
Background image of page 6
Producers of Mercury 1) Power plants that burn coal for a energy source will release Mercury as byproduct. HgS + O 2 --> (600C) Hg + SO 2 In 1999, 48 tons of mercury were released as side products. 2) Burning of industrial waste (car batteries, flashlights, fluorescent light tubes) 3) Industrial production of mercury by various chemical reactions
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Mercury Emissions Journal of Chemical Crystallography, Vol. 33, No. 8, August 2003 Hutchinson and Atwood
Background image of page 8
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Forms of Mercury Appears in two states Mercury can exist as a metallic solid Hg 0 , which is volatile. It can also exist as a stable cation Hg +2 a) Hg +2 is toxic because it can bind to sulfydryl groups in enzymes and it can also attack the kidneys causing fatal kidney failure. However, since it only has a half life of 3 days in the blood it is rapidly excreted. b) Hg +2 can be converted to methylmercury(CH 3 Hg) by microbes. Methyl mercury is hydrophobic and accumulates in body
Background image of page 10
Formation of methylmercury Occurs in anaerobic conditions such as deep soil, sediments, or in the depths of oceans. There are multiple mechanism for the conversion of Hg +2 to methyl mercury CH 3 Hg. sulfate-reducing bacteria produce H 2 S 1) Hg +2 + H 2 S ---- HgS +H 2 2) HgS + CH 3 - CH 3 Hg(II)
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Uptake of methyl Mercury In aquatic ecosystems methylmercury is absorbed by heterotrophs. Methylmercury usually comes in the uncharged chloride complex
Background image of page 12
Image of page 13
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 01/19/2011 for the course ESPM 192 taught by Professor Lindow during the Fall '10 term at Berkeley.

Page1 / 54

mercury - Mercury A element that is liquid at room...

This preview shows document pages 1 - 13. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online