Dynamic Exposure of Organisms and Passive Samplers to Hydrophobic Chemicals

CABE, University of Geneva, Sciences II, 30 Quai Ernest Ansermet, CH 1211, Geneva 4, Switzerland.
Environmental Science and Technology (Impact Factor: 5.33). 05/2009; 43(7):2206-15. DOI: 10.1021/es8029895
Source: PubMed


An insight into the dynamic aspects of the accumulation process is essential for understanding bioaccumulation as well as effect studies of hydrophobic organic chemicals. This review presents an overview of kinetic studies with organisms (fish, bivalve, crustacean, insect, worm, algae, and protozoan) as well as passive samplers (solid and liquid phase microextraction, semipermeable membrane device, polymer sheet, solid-phase extraction, Chemcatcher, etc.) for the uptake of neutral nonpolar chemicals from the aqueous phase. Information about uptake rates, elimination rates, and 95% equilibration times was collected and analyzed with diffusion based models. The present literature review suggests that the surface to volume ratio appears to be a critical parameter for the uptake rate of the more hydrophobic chemicals both for samplers and organisms. In addition, as a very first approximation, the combination of the first-order kinetic model with the assumption that diffusion through the aqueous boundary layers is rate limiting, gives a reasonable description of the experimental kinetic data. In this way, the presented model might be used to estimate uptake and elimination rate constants of chemicals by organisms or passive samplers.

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Available from: Stephane Bayen, Feb 11, 2014
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    • "Many factors can affect sampling kinetics, such as the sampler geometry, hydrodynamic conditions around the sampler, temperature and fouling on the surfaces, as well as the distribution coefficient between the sampler and water (K SW ). Of these, K SW is considered one of the most important parameters in determining whether a sampler is suitable for evaluating the time-weighted average concentration, as the time required to attain equilibrium between the sampler and water increases with increasing K SW (Huckins et al., 1999; Stuer- Lauridsen, 2005; Mazzella et al., 2007; Bayen et al., 2009; Llorca et al., 2009). Most passive samplers can run in a time-integrative mode, without much modification, for compounds with a high K SW . "
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    • "Passivsammler erfassen die chemische Aktivität der Substanzen bzw. die frei gelösten Stoffmengen im Umweltmedium (Bayen et al. 2009). Der verwendete Ansatz basiert auf der Desorption hydrophober organischer Schadstoffe (hydrophobic organic contaminant, HOC) aus Sediment und auf der Gleichgewichtseinstellung zwischen der Matrix , dem Porenwasser und dem Elastomer (Abb. "
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