GB/T 47293-2026Determination of available mercury in soil (English PDF)

1 Scope

This document describes a method for determining available mercury in soil using atomic fluorescence spectrometry with thioglycolic acid-disodium hydrogen phosphate solution extraction.

This document applies to the determination of available mercury content in arable land soil.

The limit of detection for this method is 0.2 µg/kg, and the limit of quantitation is 0.6 µg/kg.

2 Normative references

The contents of the following documents, through normative references within the text, constitute essential provisions of this document. Dated citations are not included.

For references to documents, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies.

This document.

GB/T 6682 Specifications and test methods for water used in analytical laboratories

NY/T 52 Soil Moisture Determination Method

NY/T 395 Technical Specification for Monitoring the Environmental Quality of Farmland Soil

3 Terms and Definitions

The following terms and definitions apply to this document.

4 Method Principles

The sample was extracted with thioglycolic acid-disodium hydrogen phosphate (C2H4O2S-Na2HPO4) extractant, and its mercury content was similar to that in crops.

The correlation. In acidic medium, mercury in the extract is reduced to gaseous mercury atom vapor by potassium borohydride (KBH4), which is then carried by the carrier gas (argon).

The mercury atoms are atomized in a quartz atomizer and, under the irradiation of a specially designed hollow mercury cathode lamp, the ground-state mercury atoms are excited to a high-energy state, and then return to the ground state.

When in the mercury-containing state, it emits fluorescence at a characteristic wavelength. The fluorescence intensity is directly proportional to the mercury content, and quantification is performed using the external standard method.

5 Reagents and Materials

Unless otherwise specified, all reagents and water used in this document refer to analytical grade reagents and Grade II water as defined in GB/T 6682;

Unless otherwise specified, all solutions described herein are aqueous solutions.