Dear Arsha!

The best is to use non contaminated soil from the same site maybe faraway by a distance from the contaminated spot, or even from the same area (city or town) to keep changes in the physicochemical properties as low as possible.

Regards

Yahya

Hello

As a certified reference material, most of the researchers prefer NIST 1121a Montana soil to use as a standard material. Also you need a background soil from your locality with no rigorous anthropogenic activity. That will allow you to understand the contamination range coming from man made sources. Although there are many certified samples you can get for different sedimentary soil, but for surface soil NIST samples are trusted most.

Thank you for your reply

Dear Arsha,

I think you can check in both Sigma Aldrich and Merck. They are selling certified reference material (metals in soil). I recommend to use from such prominent brands, it would be helpful to explain in your discussion. You can find the price and detailed information in following link;

https://www.sigmaaldrich.com/catalog/product/sial/spe001?lang=en®ion=SE

Good Luck!

Thank you sir.

Hello, Arsha! For the analysis of soil pollution, for example, for background indicators we take either clarks of these elements in the Earth’s crust, or soil indicators that are not affected by anthropogenic influence, for example, in our Siberia these are soils from the "Numto" natural park remote from "civilization" (Khanty Mansiysk Autonomous Okrug, Tyumen region, Russian Federation)

Thank you sir.

Dear Arsha

As a certified reference material, most of the researchers prefer NIST 1121a Montana soil to use as a standard material. Also you need a background soil from your locality with no rigorous anthropogenic activity. That will allow you to understand the contamination range coming from man made sources.

Thank you Sir.

Your question helped me too Arsha. Thank you all.