Identification of Olfactory Nuisance of Floor Products Containing Bitumens with the TD-GC-MS/O Method

Abstract

The adopted TD-GC-MS/O method helps determine the correlation between the odour signals and compounds separated on the chromatographic column, from the analysed gas mixture. It is possible to compare the retention times at which the odour signals were identified with the retention time of eluting compounds, when the test system and matrix are known. The presented study describes the details of representative samples obtained from (1) indoor air samples from a room where floor materials containing bitumen are present, (2) wooden floor staves placed in an emission chamber, and (3) fragments (chips) of the materials mentioned above, placed in glass tubes, exposed to an elevated desorption temperature. The results, presented in the paper, describe the identified odours and their intensity and assign chemical compounds to each odour, indicating their likely source of origin. The results presented in the manuscript are intended to show what methodology can be adopted to obtain intense odours from the tested samples, without losing the sensitivity derived from GC-MS. The manuscript presents representative results-case studies. The results for various types of samples were not very reproducible, related to the complex matrix of bituminous products. The enormity of compounds present in tar adhesives makes it possible to indicate only the groups of compounds that emit from these systems. They include, primarily, aliphatic, aromatic and heteroaromatic hydrocarbons, particularly Naphthalene and Phenol derivatives.

Keywords: IAQ; TD–GC–MS; bitumens; emission; odourant; olfactometry.

Figure 1

Simplified diagram of the TD–GC–MS/O chromatographic array used for the tests.

Figure 2

Diagram of a two-position four-way valve in positions (A) and (B), with the marked chromatographic column and applied restrictors.

Figure 3

(A) Wooden floor staves coated with bitumen, collected from the renovated office room (B) The same floor staves placed in the emission chamber.

Figure 4

Chips planed from wooden floor staves coated with bituminous products, ready for thermal desorption tests.

Figure 5

Chromatographic spectrum with the applied odour signals obtained for the air sample collected from the office room during renovation.

Figure 6

Chromatographic spectrum with the applied odour signals obtained for the air sample collected from the non-renovated office room.

Figure 7

Chromatographic spectrum with the applied odour signals obtained for the air sample collected from the emission chamber after three days.

Figure 8

Chromatographic spectrum with the applied odour signals obtained for the samples of floor staves exposed to elevated desorption temperature.