Journal
AQUATIC TOXICOLOGY
Volume 103, Issue 3-4, Pages 179-190Publisher
ELSEVIER
DOI: 10.1016/j.aquatox.2011.02.015
Keywords
Natural organic matter; Metal toxicity; Physicochemical characteristics; Aquatic organisms
Categories
Funding
- Government of Oman
- Natural Sciences and Engineering Research Council of Canada (NSERC)
- Canada Research Chair program
Ask authors/readers for more resources
Natural organic matter (NOM), expressed as dissolved organic carbon (DOC in mgC L-1), is an ubiquitous complexing agent in natural waters, and is now recognized as an important factor mitigating water-borne metal toxicity. However, the magnitude of the protective effect, judged by toxicity measures (e.g. LC50), varies substantially among different NOM sources even for similar DOC concentrations, implying a potential role of NOM physicochemical properties or quality of NOM. This review summarizes some key quality parameters for NOM samples, obtained by reverse osmosis, and by using correlation analyses, investigates their contribution to ameliorating metal toxicity towards aquatic biota. At comparable and environmentally realistic DOC levels, molecular spectroscopic characteristics (specific absorbance coefficient, SAC, and fluorescence index, FI) as well as concentrations of fluorescent fractions obtained from mathematical mixture resolution techniques (PARAFAC), explain considerable variability in the protective effects. NOM quality clearly influences the toxicity of copper (Cu) and lead (Pb). NOM quality may also influence the toxicity of silver (Ag), cadmium (Cd) and inorganic mercury (Hg), but as yet insufficient data are available to unequivocally support the latter correlations between toxicity reduction and NOM quality predictors. Cu binding capacities, protein-to-carbohydrate ratio, and lipophilicity, show insignificant correlation to the amelioration offered by NOMs, but these conclusions are based on data for Norwegian NOMs with very narrow ranges for the latter two parameters. Certainly, various NOMs alleviate metal toxicity differentially and therefore their quality measures should be considered in addition to their quantity. (C) 2011 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available