ISO 17378-2:2014 水質 — ヒ素とアンチモンの測定 — Part 2: 水素化物生成原子吸光分析（HG-AAS）を使用した方法 | ページ 2

Foreword

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The committee responsible for this document is ISO/TC 147, Water quality, Subcommittee SC 2, Physical, chemical and biochemical methods.

This first edition of ISO 17378-2 cancels and replaces ISO 11969:1996, which has been technically revised.

ISO 17378 consists of the following parts, under the general title Water quality — Determination of arsenic and antimony:

• Part 1: Method using hydride generation atomic fluorescence spectrometry (HG–AFS)
• Part 2: Method using hydride generation atomic absorption spectrometry (HG–AAS)

Introduction

This part of ISO 17378 should be used by analysts experienced in the handling of trace elements at very low concentrations.

Arsenic concentrations in natural waters are highly variable, from <10 μg/l to as high as several milligrams per litre in some parts of Asia, South America and the USA, notable in the Ganges delta where arsenic poisoning from contaminated tube wells is a serious problem. Antimony concentrations in natural waters are generally well below 10 μg/l. Arsenic and antimony occur naturally in organic and inorganic compounds and may have oxidation states −III, 0, III and V.

In order to fully decompose all of the arsenic or antimony compounds, a digestion procedure is necessary. Digestion can only be omitted if it is certain that the arsenic or antimony in the sample can form a covalent hydride without the necessity of a pre-oxidation step.

The user should be aware that particular problems could require the specification of additional marginal conditions.

The method for determining arsenic or antimony is identical in all aspects except for the preparation of standard solutions to be tested. To avoid repetition or duplication the text refers to both arsenic and antimony where the text is equally applicable to both instances. The subclause dealing with preparation of standard solutions is divided into 5.11.1, which deals with solutions of arsenic, and 5.11.2, which deals with solutions of antimony.

1 Scope

This part of ISO 17378 specifies a method for the determination of arsenic and antimony. The method is applicable to drinking water, surface water, ground water, and rain water. The approximate linear application range of this part of ISO 17378 for both elements is from 0,5 µg/l to 20 µg/l. Samples containing higher concentrations than the application range can be analysed following appropriate dilution.

Generally sea water is outside the scope of this part of ISO 17378. Sea water samples can be analysed using a standard additions approach providing that this is validated for the samples under test. The method is unlikely to detect organo-arsenic and organo-antimony compounds.

The sensitivity of this method is dependent on the selected operating conditions.

2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

Bibliography