Related Experiment Videos
Passive air sampling using semipermeable membrane devices at different wind-speeds in situ calibrated by performance
Hanna S Söderström1, Per-Anders Bergqvist
1Environmental Chemistry, Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden. hanna.soderstrom@chem.umu.se
Environmental Science & Technology
|October 19, 2004
Summary
High wind speeds increase the sampling rates of semipermeable membrane devices (SPMDs) for organic pollutants like polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Performance reference compounds (PRCs) effectively assess sampling conditions and wind effects.
Area of Science:
- Environmental Chemistry
- Analytical Chemistry
- Air Quality Monitoring
Background:
- Semipermeable membrane devices (SPMDs) are passive samplers for airborne organic pollutants.
- Understanding factors influencing SPMD sampling rates, such as wind speed, is crucial for accurate air quality assessments.
- Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) are significant environmental contaminants.
Purpose of the Study:
- To investigate the impact of high wind speeds on SPMD sampling rates for PAHs and PCBs.
- To evaluate the utility of performance reference compounds (PRCs) in assessing wind effects and sampling variability.
- To determine the effectiveness of a protective sampler design in mitigating wind-induced uptake and release rates.
Main Methods:
- SPMDs were deployed in a wind tunnel under controlled wind speeds (6-50 m s⁻¹).
- Protected and unprotected SPMDs were used to assess the influence of sampler design.
- PRCs were incorporated to monitor sampling conditions and chemical analysis variability.
- Air concentrations of PAHs and PCBs were quantified in exposed SPMDs.
Main Results:
- SPMD sampling rates for PAHs and PCBs increased significantly with higher wind speeds.
- Uptake was primarily controlled by the boundary layer at the membrane-air interface.
- PRC data demonstrated a coefficient of variance of 28-46% for air concentrations, confirming their predictive ability.
- The protective sampler design effectively reduced internal wind speeds, lowering uptake and release rates.
Conclusions:
- Wind speed is a critical factor influencing SPMD sampling efficiency for volatile organic compounds.
- PRCs are reliable indicators for assessing environmental conditions and chemical analysis performance during passive sampling.
- Sampler design plays a vital role in standardizing SPMD performance under varying atmospheric conditions.