Quartz and cristobalite – Determination of quartz and cristobalite in workplace air using X-ray diffraction (XRD)
Air Monitoring Method
Markus Mattenklott1 (Method development)Thomas Helmut Brock2 (Head of the working group “Analytics”)
Ralph Hebisch3 (Head of the working group “Air Analyses” of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area, Deutsche Forschungsgemeinschaft)
Andrea Hartwig4 (Chair of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area, Deutsche Forschungsgemeinschaft)
MAK Commission5
1 Institute for Occupational Safety and Health (IFA) of the German Social Accident Insurance (DGUV), Alte Heerstraße 111, 53757 Sankt Augustin, Germany
2 German Social Accident Insurance, Institution for the raw materials and chemical industry, Prevention – Department of Hazardous Substances, Biological Agents and Analytical Chemistry, Kurfürsten-Anlage 62, 69115 Heidelberg, Germany
3 Federal Institute for Occupational Safety and Health (BAuA), Friedrich-Henkel-Weg 1-25, 44149 Dortmund, Germany
4 Institute of Applied Biosciences, Department of Food Chemistry and Toxicology, Karlsruhe Institute of Technology (KIT), Adenauerring 20a, Building 50.41, 76131 Karlsruhe, Germany
5 Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area, Deutsche Forschungsgemeinschaft, Kennedyallee 40, 53175 Bonn, Germany
Abstract
This analytical method is a validated measurement procedure for the determination of quartz [14808-60-7] and cristobalite [14464-46-1] in workplace air after personal or stationary sampling. Sampling is performed by drawing a defined volume of air through a particle filter using a suitable flow-regulated pump. After gravimetric determination, the respirable fraction of quartz or cristobalite retained on the filter is analysed by an X-ray diffractometer. The relative limits of quantification (LOQ) are for a sampling period of two hours with air sampling volumes of 0.24 to 45 m3 for quartz 0.0040 to 0.38 mg/m3 and for cristobalite 0.0020 to 0.19 mg/m3. For a sampling period of eight hours the LOQ are between 0.0010 and 0.094 mg/m3 and between 0.0005 and 0.047 mg/m3, respectively. The expanded uncertainty is 28% for 0.075 mg/m3 of quartz and is estimated to be lower for cristobalite. This analytical method has been accredited by the accident insurance companies for the detection in workplace air of substances that are carcinogenic, mutagenic or toxic to reproduction. This method has been tested and recommended for the determination of quartz and cristobalite in work areas by the German Social Accident Insurance (DGUV). Both personal and stationary sampling can be performed for measurements in order to evaluate work areas.
