Passive Sampling of Nonpolar Compounds in Sediments
Abstract
Passive sampling is a powerful tool for determining the concentrations of truly dissolved contaminants in pore waters as well as for measuring the size of the exchangeable contaminant fraction in the sediment phase. Application of passive sampling of nonpolar contaminants in sediments is technically easy, but conceptually difficult, compared with traditional batch water sampling. The sorption capacity of the samplers and the (equivalent) water sampling rate are the two parameters that are needed to conceptualize the sampling process. These parameters also determine the value of the detection limits and the rate at which passive samplers equilibrate with their environment. After discussing contaminant uptake by passive samplers in an infinite water volume, their behavior in sediments will be dealt with using two practical examples. Exposure to stagnant sediments will be contrasted with exposure to sediment slurries. Passive sampler exposure to sediment slurries at low sampler/sediment phase ratios allows concentrations of dissolved contaminants in the pore water to be estimated. Exposure at high sampler/sediment phase ratios yields information on the size of the contaminant fraction in the sediment that is easily exchangeable with the pore water. Guidelines for designing passive sampler exposures to contaminated sediments will be discussed, and sources of uncertainties in the results will be highlighted.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 02, 2010
- Accession Number
- ADA554160
Entities
People
- Foppe Smedes
- Kees Booij
Organizations
- Royal Netherlands Institute of Sea Research