Air limit values for "soluble" metal compounds exist in many European limit value lists. It is generally not described how the solubility is to be taken into consideration analytically during the verification of the corresponding air limit values. The objective of the project was to develop a convention for better comparability and reproducibility of the analytical results in the determination of "soluble" metal compounds.
In the analytical method recommended by the convention, diluted hydrochlorid acid is used as extracting agent (alternatively: diluted nitric acid for metals which form difficultly soluble halides). Compared with water, which is frequently used for the determination of soluble metal compounds, hydrochlorid has the advantage of suppressing the effects through dust components (e. g. varying pH factors). This leads to better analytical results. The resulting solutions can be analysed without further operations with the well-known analytical methods of metal-analysis, Atomic absorption spectroscopy/inductively coupled plasma with mass spectrometry (AAS, ICP-MS).
The recommended method of dissolution is to be used as a standard in eight European institutes for occupational safety. This resolution was passed during the meeting of European occupational safety institutes in 1999 in Ljubljana/Slovenia.
-cross sectoral-Type of hazard:
Arbeitsbedingte Gesundheitsgefahren, GefahrstoffeCatchwords:
measuring methodsDescription, key words:
metals, solubility, sample dissolution, limit values