| Title: | Evaluation of VOC measurments in the EXPOLIS study. Air Pollution Exposure Distributions within Adult Urban Urban Populations in Europe |
| Author(s): | Jurvelin J; Edwards R; Saarela K; Laine-Ylijoki J; De Bortoli M; Oglesby L; Schlapfer K; Georgoulis L; Tischerova E; Hanninen O; Jantunen M; |
| Address: | "Division of Environmental Health, KTL-National Public Health Institute, Kuopio, Finland. jurvelin@jypoly.fi" |
| ISSN/ISBN: | 1464-0325 (Print) 1464-0325 (Linking) |
| Abstract: | "Personal exposures and microenvironment concentrations of 30 target VOCs were measured for 401 participants living in five European cities as a part of the EXPOLIS (Air Pollution Exposure Distributions within Adult Urban Populations in Europe) study. Measurements in Basel used an active charcoal (Carbotech) adsorbent as opposed to the Tenax TA used in the other study centres. In addition, within each centre, personal and microenvironment VOC sampling required different sampling pumps and, because of different sampling durations, different sampling flow rates. Thus, careful testing of the sampling and analysis procedures was required to ensure accuracy and comparability of collected data. Monitor comparison tests using Tenax TA showed a mean VOC concentration ratio of 0.95 between the personal and microenvironment monitors. The LODs for the target VOCs using Tenax TA ranged from 0.7 to 5.2 microg m(-3). The LODs for the 14 target compounds quantifiable using Carbotech ranged from 0.9 to 3.2 microg m(-3). Tenax TA field blanks showed no remarkable contamination with the target VOCs, except benzaldehyde, a known artefact with this adsorbent. Thus, the diffusion barrier system used prevented contamination of Tenax TA samples by passive diffusion during non-sampling periods. Duplicate and parallel evaluations of the Tenax TA and Carbotech showed an average difference of < 17% in VOC concentrations within the sampling methods, but a systematic difference between the methods (Tenax TA: Carbotech concentration ratio = 1.18-2.36). These field evaluations and quality assurance tests showed that interpretation and comparison of the results in any VOC monitoring exercise should be done on a compound by compound basis. It is also apparent that carefully planned and realised QA and QC (QA/QC) procedures are needed in multi-centre studies, where a common sampling method and laboratory analysis technique are not used, to strengthen and simplify the interpretation of observed VOC levels between participating centres" |
| Keywords: | Air Pollution/*analysis *Environmental Exposure Environmental Monitoring/methods/*standards Organic Chemicals/*analysis Reproducibility of Results Specimen Handling Volatilization; |
| Notes: | "MedlineJurvelin, J Edwards, R Saarela, K Laine-Ylijoki, J De Bortoli, M Oglesby, L Schlapfer, K Georgoulis, L Tischerova, E Hanninen, O Jantunen, M eng Evaluation Study Research Support, Non-U.S. Gov't England 2001/03/17 J Environ Monit. 2001 Feb; 3(1):159-65. doi: 10.1039/b007600g" |
