A comparative and Critical Evaluation of Different Sampling Materials in the Measurement of Odour Concentration by Dynamic Olfactometry

The selection of an odour sampling device and relative materials may influence the composition of the resulting odour sample. Current literature is limited to discussing how the measurement of emission rates derived from the same odour source could be related to materials and methods. There is therefore compelling evidence that current odour sampling practices should have greater regard for the fundamental physical and chemical principles, the nature of the odour source and the conditions created by the sampling device. Additional studies are necessary to identify the most appropriate situations under which the use of these devices may or may not be correct. The scope of this study is to investigate the influence on the determination of odour concentration with dynamic olfactometry, according to EN 13725 (2003) standards, applying different initial sampling condition, with the objective to define the optimal criteria to evaluate the odour concentration and obtain the highest repeatability and accuracy of the sensorial measure. A critical evaluation was carried out in relation to the same odour source with the comparison of sampling bag materials (Nalophantm, Tediar®TeflonTM) and intervals of time elapsed between the sampling and analysis phase (3, 7, 14, 30, 48 h). The results obtained show that the selection of an odour sampling materials may influence the composition of the resulting odour sample. There is therefore compelling evidence that current odour sampling practices should have regard for these factors and identify the situations under which these material and methods may be used appropriately