Method for detecting bio-available cadmium in soil

Abstract

A method for detecting bio-available cadmium in soil includes steps: S100, sample collection and pretreatment, to be more specific, sampling soil, subjecting sampled soil to air drying at the room temperature, grinding, and filtering through a 200-mesh screen to obtain a soil sample; weighing 1-5g of the soil sample, adding into a 250mL polytetrafluoroethylene centrifugal cup, adding 25mL of 1mol / L ammonium chloride solution and 25mL of 80% ethanol solution, cleaning through an ultrasonic cleaner, centrifuging through a centrifuge, filtering supernatant through a filter membrane to obtain extract liquid, and adopting HNO3 solution in concentration of 1% to obtain a constant volume; S200, determination of the concentration of bio-available cadmium in the extract liquid, to be more specific,adopting an inductively coupled plasma source mass spectrometer for creating a standard curve for determining different concentrations of bio-available cadmium according to an inductively coupled plasma mass spectrometry method; adopting the inductively coupled plasma source mass spectrometer for measuring concentration of bio-available cadmium in the extract liquid according to the standard curve; S300, result analysis, to be more specific, calculating the content of bio-available cadmium in the soil sample according to measured soil sample mass and measured extract liquid concentration.

Description

technical field [0001] The invention relates to the technical field of soil environmental protection detection, in particular to a method for detecting biologically available cadmium in soil. Background technique [0002] The environmental behavior and ecological effects of heavy metal elements do not depend on their total amount in environmental matrix such as soil or sediment, but mainly depend on their existing phase and corresponding quantity ratio. The different chemical forms of metals in the environmental matrix determine their mobility and bioavailability; the research on heavy metals in bioavailable state can provide a reliable basis for evaluating environmental pollution, establishing environmental standards, and preventing and remediating environmental pollution. Cadmium is a widely distributed metal element, which is located in the IIB and fifth period of the periodic table of elements. It is mainly used in the battery industry, followed by pigments, paints and e...

AI Technical Summary

Problems solved by technology

Cadmium is a widely distributed metal element, which is located in the IIB and fifth period of the periodic table of elements. It is mainly used in the battery industry, followed by pigments, paints and electroplating. Cadmium pollution is widely distributed and has strong biological toxicity. However, due to the complexity of the environmental matrix where it is located, it is difficult to accurately extract and detect the content of cadmium, especially the extraction of active cadmium that is easily absorbed by the human body, animals or plants is even more difficult.

At present, the extraction methods of biologically available cadmium in soil mainly include step-by-step extraction method and single extraction method, among which step-by-step extraction mainly includes BCR method and Tessier method, but the step-by-step extraction method has complex and time-consuming extraction process, and the extraction process is difficult. There is mutual interference between the various phase states, resulting in the problem of series phases; in the one-step extraction method, the more commonly used extractants at home and abroad include DTPA, EDTA and HCl, etc., but these acidic solutions have low pH values, making some non-substitutes in the soil The heavy metals in the adsorbed state are also extracted, causing a large deviation in the experimental results

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