Alternatives for Benzene in the Extraction of Bitumen Fume from Exposure Sample Media

Abstract

Benzene is frequently used to extract collected bitumen fumes from personal sampler substrates. However, this solvent is particularly dangerous because of its carcinogenicity (group 1 of the International Agency for Research on Cancer classification). Therefore, to prevent the exposure of laboratory technicians to benzene during the fume extraction step from samplers, a compromise had to be found to identify a less toxic solvent with the same extraction capacity. To compare the extraction capacities of selected solvents, bitumen fumes were generated in the laboratory from three different batches of road surfacing bitumen collected on dedicated bitumen fume samplers. The samplers were then extracted by benzene and the solvents tested. Of 11 selected solvents less toxic than benzene and used in studies on bitumen and bitumen fume analyses, n-hexane and n-heptane were identified as alternatives to benzene. In particular, the results demonstrated that n-heptane was the best candidate solvent for benzene replacement, due to its extraction efficiency comparable to benzene for the three bitumen fumes tested and its low toxicity, which is highly compatible with benzene replacement.

Polycyclic aromatic hydrocarbons (PAHs) skin permeation rates change with simultaneous exposures to solar ultraviolet radiation (UV-S)

“…The concentrations of individual PAHs in the mixture we used were a result from several tries with lower initial PAH concentrations which were below the limit of detection, making it difficult to construct permeation curves. The BFC we generated (Sutter et al 2016) and applied to the skin, contained somewhat different individual PAH concentration ratios compared to the personal samples reported in the literature. Our BFC had lower amounts of pyrene and anthracene than measured among pavers, and this could be due to the loss of the vapor phase in our sample.…”

“…The fume from obtained road construction bitumen (CAS 8052-42-4; CTW-Strassenbaustoffe AG, Switzerland) was generated in a week long process. Information regarding the bitumen fume generator itself has been described previously (Sutter et al 2016). Briefly, the bitumen was heated in a vessel to 170º C, and fume collected in a condensation system, before extraction with dichloromethane.…”

Performances of a Bitumen Fume and Condensate Generation System for Sampling Method Development

“…12 personal samplers can be placed inside the exposure chamber for homogeneity and quality tests. The samplers were the same as those used in the study by Sutter et al [10]. They were designed with a 37 mm polystyrene closed-face cassette with a 4 mm orifice (Supelco Sigma Aldrich), containing a PTFE membrane with pores of 1 μm (Membrane GelmanZefluor 1 μm -37 mm, Supelco Sigma Aldrich), connected to an Amberlite™ XAD-2 400/200 mg sorbent tube (ORBO 609 400/200 mg XAD-2, Supelco Sigma Aldrich).…”

Sample Preparation and Analytical Methods for Identifying Organic Compounds in Bituminous Emissions

“…Method 5042 requires PTFE filters attached to pumps that can control the air flow, the pumps are run for a set time to standardise the volume that moves through them. Once the set volume of air has moved through the filters, they are weighed to measure total particulate matter (TOM) and then extracted with solvents to measure PAH content gravimetrically as benzene soluble matter (BSM) or solvent soluble matter (SSM) if using anything other than benzene [42]. This measurement is converted to mass/volume allowing an estimation of the concentration of particulates and aromatics in the air at worksites or from laboratory samples.…”