From Basel: Applications of Innovative Passive Sampling and Dosing
Annika Jahnke, Stockholm University
Passive sampling methods offer promising tools in studies of partitioning processes between environmental compartments, in risk-based decision-making (e.g., at contaminated sites) and in the assessment of bioaccumulation, exposure and (eco)toxicological effects.
A major advantage of passive sampling approaches is that they provide freely dissolved concentrations, which often can be considered as the effective concentration for environmental partitioning processes, bioaccumulation and toxicity. Another benefit is that some passive samplers enrich complex mixtures of chemicals present in the environment, which can then be identified by chemical analysis or characterized with bioassays. Numerous passive sampling devices have been developed for both in situ and laboratory-based use, covering matrices such as soil, sediment, water, air, vegetation and biota as well as a range of chemicals of concern.
This year’s session expressed the versatility of passive sampling and dosing for environmental fate, bioaccumulation and toxicity studies. Eleven platform and four poster spotlight presentations clearly showed the breadth of innovative applications of passive sampling and dosing used today. The studies included the following aspects:
- Many different chemicals, from metals to organic analytes, from classical to emerging compounds, from non-polar to polar chemicals, from non-ionic to ionic compounds, as well as surfactants, parent compounds and their associated metabolites
- Single compounds to complex mixtures
- A broad range of sampler formats, including polar organic chemical integrative samplers (POCIS), ion exchange membranes, solid-phase microextraction fibers, semi-permeable membrane devices (SPMD), Chemcatcher, XAD-2, porous organogels and polymeric phases such as polyoxymethylene (POM), polydimethylsiloxane (PDMS) and low-density polyethylene (LDPE)
- Passive dosing providing constant exposure conditions in tests and a more solid basis for toxicological research
- A broad range of studied matrices such as drinking and surface waters, sediment, soil, air, vegetation and biotest media
- Different applications within research, monitoring and risk assessment
Kilian Smith opened the session by introducing the application of passive sampling devices for sampling and dosing of organic mixtures for toxicity testing. His particular focus was on combining passive sampling and dosing to transfer mixture exposure from the environment into the laboratory assay. Passive dosing was also shown to be suitable to provide constant exposure conditions of metabolizable chemicals in bioassays, which allowed toxicokinetics and time-dependent responses to be studied on a more solid basis (Kwon).
Established passive sampling technologies such as samplers for polar compounds were applied to overcome limitations of very low concentrations in drinking water supplies (Metcalfe). Low concentrations were also the topic of an application of PDMS passive samplers for the detection of pyrethroids and organophosphate pesticides whose environmental quality standards normally pose an analytical challenge (Moschet). The session’s contributions clearly demonstrated that passive sampling has left the realm of method development, and the focus of studies is now on application in environmental fate studies including the assessment of peak (accidental spill) scenarios. New materials such as ion-exchange membranes were applied to sample ionic compounds (Oemisch).
Some innovative passive sampling formats were presented such as a kite-drawn air sampler applied in Antarctica (Dachs). Passive samplers were tested as a substitute for studying the bioaccumulation and depuration of chemicals into and from mussels (Fisher) and fish (Schäfer). Ratios in activity and fugacity were determined from passive sampling data to evaluate the direction of diffusive transfer between soil and the atmosphere (Beckingham), and between sediment and the overlying water column, including a link to bioaccumulation in juvenile perch (Sobek).
The abstract from the presentation of each author in parenthesis above can be found here.
Author contact information: Annika.Jahnke@itm.su.se
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