Τίτλος:
Evaluation of VOC measurements in the EXPOLIS study
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
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 mug m(-3). The
LODs for the 14 target compounds quantifiable using Carbotech ranged
from 0.9 to 3.2 mug 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.
Συγγραφείς:
Jurvelin, J
Edwards, R
Saarela, K
Laine-Ylijoki, J
De
Bortoli, M
Oglesby, L
Schlapfer, K
Georgoulis, L and
Tischerova, E
Hanninen, O
Jantunen, M
Περιοδικό:
Journal of Environmental Monitoring
Εκδότης:
ROYAL SOC CHEMISTRY
