Sampling and Analysis of Bitumen Fumes: Comparison of German and French Methods to Determine a Conversion Formula

Abstract

Bitumen is classed as possibly carcinogenic to humans according to the International Agency for Research on Cancer. Data on individual exposure to bitumen fumes is therefore required to highlight the exposing situations and develop methods to prevent them. The Institute for Occupational Safety and Health of the German Social Accident Insurance (IFA) and the French National Research and Safety Institute for the Prevention of Occupational Accidents and Diseases (INRS) have both developed methods to measure individual exposure. The objective of this study was to determine a conversion factor to allow interconversion of data acquired by the two methods. To develop this conversion factor, comparative laboratory and workplace tests were performed according to both the IFA method (No. 6305) and the INRS method (MetroPol M-2). The amounts of organic material collected on the filters and XAD-2 beds were compared. The results revealed differences between the sampling and analytical methods that could be linked to sampler design, extraction solvent, and the detection method used. The total quantification returned by the two methods—the sum of the masses quantified on filter and XAD-2 bed for each sampler—were correlated in both controlled and real-life tests. A conversion equation was therefore determined, based on field tests: C_IFA = 1.76 C_INRS ± 0.39 (R² = 0.99) that is applicable to total quantification data. This formula can be applied to data acquired by the two institutes to increase the number of data points available on exposure to bitumen fumes in various conditions, and thus increase the statistical power of studies into occupational prevention.