Carbon disulfide - Determination of carbon disulfide in workplace air using headspace gas chromatography...

The working group "Air Analyses" of the German Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area (MAK Commission) developed and verified the presented analytical method. It is used to determine the levels of carbon disulfide [75-15-0] that occur in the workplace air. The method covers concentrations in the range from one tenth to twice the current German occupational exposure limit value (OELV) of 30 mg/m³. It is also suitable for monitoring compliance with the MAK value of 16 mg/m³ and the short-term exposure limit (STEL; excursion factor 2). Samples are collected by drawing a defined volume of air through a sampling tube filled with activated charcoal using a flow regulated pump at a maximal volumetric flow rate of 0.333 l/min. Exposure during the shift is measured with a sampling period of 2 hours (up to 8 hours, depending on the volumetric flow) and the short-term exposure with a period of 15 minutes. The carbon disulfide adsorbed to the activated charcoal is extracted with toluene and analysed by headspace gas chromatography with flame photometric detection. The quantitative determination is based on multiple-point calibrations with an internal standard. A relative limit of quantification (LOQ) of 0.5 mg/m³ is obtained for an air sample volume of 40 litres and an application volume of 18 ml. As the relative LOQ for a sample volume of 5 litres is below 5 mg/m³, the STEL can also be measured. The recovery, which has to be considered for the calculation of the results, is approx. 70% and the expanded uncertainty is below 22% for a sampling period of 2 hours and below 23% for a period of 15 minutes.