According to data of my PhD thesis, significant positive correlation was determined between Hg and COD parameters detected in water of Emet Stream Basin (TURKEY) at the 0.01 level (n=32).

(Tokatlı, C., 2012. An Investigation on Heavy Metal Accumulations In Water, Sediment And Fishes of Emet Stream. Ph. D. Thesis, Dumlupınar University, Institution of Science, Department of Biology)

[I] Coal combustion is the single largest source of mercury emissions to the air, due to the fact that mercury is contained as a trace element in coal.

[II]Cement production and waste disposal such as medical and municipal waste incineration are next most significant resources. Incinerator ashes and discarded products dumped at landfill sites create another source of potential exposure to soil and water.

[III]Health-care facilities are one of the main sources of mercury release into the atmosphere because of emissions from the incineration of medical waste.

[IV]After coal combustion, crematoria are among the most

signifi cant contributors of mercury air emissions .

[V] Waste streams (used products, landfills, emissions

from industrial sources) ends up in the sewage sludge

that is used as agricultural fertiliser. If contaminated

with mercury, it causes contamination of soil

[VI]Mercury emissions to air is caused from:

Non-ferrous metals (Zn,Pb),pig iron & steel;Waste disposal (incineration);

Cement production;Coal combustion ;Oil combustion;Power plants

Chlor-alkali

[VII]Mercury emissions – to water:

[A] Hg also enters the environment through discharges of waste from various

Industries; the Chlor-alkali industries being the major contributors.

[B]Then there are sediments, fish and Marine mammals.

[C] Another major source is the discharge dental waste

[D] Chemically, the reactive form of Hg in auatic environments is Hg(II). Where it is present as METHYL MERCURY and the phenomenon is called METHYLATION. In the aqutic conditions, SULPHATE REDUCING BATERIA have been identified as the most important Hg- METHYLATING ORGANISMS with COBALMIN BEING THE PRINCIPAL SOURCE OF METHYYL GROUP.