Metal bioavailability models: current status, lessons learned, considerations for regulatory use, and the path forward

Mebane, Christopher A.; Chowdhury, M. Jasim; De Schamphelaere, Karel A.C.; Lofts, Stephen ORCID:; Paquin, Paul R.; Santore, Robert C.; Wood, Chris M.. 2020 Metal bioavailability models: current status, lessons learned, considerations for regulatory use, and the path forward. Environmental Toxicology and Chemistry, 39 (1). 60-84.

Before downloading, please read NORA policies.
N526381PP.pdf - Accepted Version

Download (1MB) | Preview


Since the early 2000s, biotic ligand models and related constructs have been a dominant paradigm for risk assessment of aqueous metals in the environment. We critically review 1) the evidence for the mechanistic approach underlying metal bioavailability models; 2) considerations for the use and refinement of bioavailability‐based toxicity models; 3) considerations for the incorporation of metal bioavailability models into environmental quality standards; and 4) some consensus recommendations for developing or applying metal bioavailability models. We note that models developed to date have been particularly challenged to accurately incorporate pH effects because they are unique with multiple possible mechanisms. As such, we doubt it is ever appropriate to lump algae/plant and animal bioavailability models; however, it is often reasonable to lump bioavailability models for animals, although aquatic insects may be an exception. Other recommendations include that data generated for model development should consider equilibrium conditions in exposure designs, including food items in combined waterborne–dietary matched chronic exposures. Some potentially important toxicity‐modifying factors are currently not represented in bioavailability models and have received insufficient attention in toxicity testing. Temperature is probably of foremost importance; phosphate is likely important in plant and algae models. Acclimation may result in predictions that err on the side of protection. Striking a balance between comprehensive, mechanistically sound models and simplified approaches is a challenge. If empirical bioavailability tools such as multiple‐linear regression models and look‐up tables are employed in criteria, they should always be informed qualitatively and quantitatively by mechanistic models. If bioavailability models are to be used in environmental regulation, ongoing support and availability for use of the models in the public domain are essential.

Item Type: Publication - Article
Digital Object Identifier (DOI):
UKCEH and CEH Sections/Science Areas: Pollution (Science Area 2017-)
ISSN: 0730-7268
Additional Keywords: metal bioavailability models, speciation, bioaccumulation, biotic ligand models, mechanistic models
NORA Subject Terms: Ecology and Environment
Date made live: 12 Feb 2020 17:20 +0 (UTC)

Actions (login required)

View Item View Item

Document Downloads

Downloads for past 30 days

Downloads per month over past year

More statistics for this item...