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Article Arsenic Contamination in Soil and Sediment in India: Sources...

Article Assessment of heavy metals and arsenic contamination in the ...

Dear Mrs. Mejjad,

your question is rather complex and an answer strongly depends on the Eh of the host sediments in question. If you have to deal with reducing conditions have a close look at the sulfide system, often the Fe sulfides are the main source in sediments. If you have oxidizing conditions where you might expect arsenate complexes direct your thoughts to other similar anion complexes such as phosphate, and vanadate which can substitute for this complex in the lattice of many minerals. A rather unspecific and the more so complex system is that of the organo-metallic complexes that might be present in these low-T systems as well. Your lithotype, be it more argillaceous or arenaceous may already put you on the right scent in terms of the redox conditions. This is only a quick-look method which I can give you based on the present dataset.

With kind regards

H.G.Dill

Dear Professor Harald G. Dill

Thank you very much for the prompt reply.

Excellent response as usual. 

Thank you Mr. Kenneth M Towe  for your interesting response, 

It was interesting because I don't know how to search google.

Dear Dr. Kundan Sagar

Thank you for for the prompt reply, And for sharing with me this documents. 

Dear Nezha Madam,

Several literature are found on the mobilization of arsenic (As) in groundwater. A brief comment on the topic is given below for your easy understanding and to create interest to enter into the subject:

The high concentration of arsenic in groundwater is found in many parts of the world like USA, China, Japan, Peru, Germany, France Romania, south-east Asian countries etc. The geogenic As contamination in groundwater on large scales are reported from recent sediments of river deltas in south-east Asia (India, Bangladesh, Vietnam, Combodia).

As (a semi-metal or metalloid) occurs in the crustal rock, sea, soil, and organisms. Dominant natural arsenic bearing minerals include realgar (AsS), Orpiment (As2S3), Iollingite (FeAs2), arsenopyrite (FeAsS). Arsenopyrite is the most common arsenic ore mineral. As concentration is generally low in igneous rocks and higher in metamorphic and some sedimentary rocks [ Pelitic (Slates and Phyllites) and argillaceous (black slates, coals)]. The sulphide minerals (pyrite - the most abundant) tend to be rich in As.

The sources of As due to anthropogenic activities include mine tailings, mine effluents and effluents from industry which uses arsenic compounds, combustion of coal etc.

Arsenic contamination of groundwater is generally found from geological sources and the release of As is occurred by the following ways (present thoughts):

Please go through the attached Workshop Proc. - Discussions on occurrence and geochemical behaviour of arsenic by several researchers.

Give your feedback. Regards