Freshwater ecotoxicity characterization factors for aluminum
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Aluminum (Al) is an abundant, non-essential element with complex geochemistry and aquatic toxicity. Considering its complex environmental behavior is critical for providing a reasonable estimate of its potential freshwater aquatic ecotoxicity in the context of Life Cycle Impact Assessment (LCIA).
Al characterization factors (CFs) are calculated using the following: (1) USEtox™ model version 2.1 for environmental fate, (2) MINEQL+ to estimate the distribution of Al between the solid phase precipitate and total dissolved Al, (3) WHAM 7 for Al speciation within the total dissolved phase, and (4) Biotic Ligand Model (BLM) and Free Ion Activity Model (FIAM) for ecotoxicity estimation for seven freshwater archetypes and default landscape properties for the European continent. The sensitivity of the CFs to aquatic chemistry parameters is calculated. New CFs are compared with Dong et al. (Chemosphere 112:26–33, 2014) and default CF calculated by USEtox 2.1.
Results and discussion
Al CFs vary over 5 orders of magnitude between the seven archetypes, with an arithmetic average CFave of 0.04 eq 1,4-DCB (recommended for use), geometric mean CFgeo of 0.0014 eq 1,4-DCB, and weighted average CFwt of 0.026 eq 1,4-DCB. These values are lower (less toxic) than those for Cu, Ni, Zn, and Pb (with one exception). The effect factor (EF) contributed most to this variability followed by the bioavailability factor (BF), varying over 8 and 4 orders of magnitude, respectively. These revised CFs are 2–6 orders of magnitude lower than those presented by Dong et al. (Chemosphere 112:26–33, 2014) mainly because of consideration of Al precipitation.
Freshwater archetype-specific Al CFs for freshwater ecotoxicity that address the effect of Al speciation on bioavailability (BF) and ecotoxicity (EF) have been calculated, and a CF of 0.04 eq 1,4-DCB is recommended for use in generic LCA. For site-specific LCA, the choice of water chemistry and, in particular, pH, and consideration of metal precipitation could significantly influence results.
Incorporating estimates of metal speciation and its effect on aquatic toxicity is essential when conducting LCIA. Along with metal speciation estimates, the values derived from the definition of water chemistry parameters must also be included into LCIA. For site-generic assessments, we recommend using the arithmetic average of metal CFs. We also recommend using FIAM as a suitable alternative to BLM to estimate EF if the latter is not available. Consideration of metal speciation is essential for providing more realistic estimates of Al freshwater ecotoxicity in the context of LCIA.
KeywordsAluminum Ambient chemistry Bioavailability Characterization factor (CF) Life Cycle Impact Assessment (LCIA) Metal speciation-complexation Metals
We thank Bob Santore (HydroQual Inc.) and his group for sharing BLM parameters and chronic ecotoxicity test data for Al exposure to aquatic organisms. We also thank Eirik Nordheim (EAA), and Chris Bayliss and Pernelle Nunez (International Aluminium Institute) for support throughout the project, and for facilitating data for model calculations. Bill Adams (Rio Tinto) provided the FOREGS stream water monitoring data for EU.
- Bowen HJM (1966) Trace elements in biochemistry. Academic Press, London, p 241Google Scholar
- Campbell PGC (1995) Interactions between trace metals and aquatic organisms: a critique of the free-ion activity model. In: Tessier A, Turner DR (eds) Metal speciation and bioavailability in aquatic systems, vol 1. John Wiley, New York, pp 45–102Google Scholar
- Diamond M, Gandhi N, Adams W, Atherton J, Bhavsar S, Bullé C, Campbell P, Dubreuil A, Fairbrother A, Farley K, Green A, Guinée J, Hauschild M, Huijbregts M, Humbert S, Jensen K, Jolliet O, Margni M, McGeer J, Peijnenburg W, Rosenbaum R, van de Meent D, Vijver M (2010) The Clearwater consensus: the estimation of metal hazard in fresh water. Int J Life Cycle Assess 15:143–147CrossRefGoogle Scholar
- Gandhi N, Huijbregts MAJ, van de Meent D, Peijnenburg WJGM, Guinée J, Diamond ML (2011c) Revised method of hazard and ecological risk assessments for calculating Comparative Toxicity Potentials of metals for which BLMs are not available. SETAC Europe, Milan, May 2011. Poster presentationGoogle Scholar
- Hem JD (1986) Geochemistry and aqueous chemistry of aluminium. Kidney Int 18:S3–S7Google Scholar
- Huijbregts MAJ, Thissen U, Guinée J, Jager T, Kalf D, van de Meent D, Ragas AMJ, Sleeswijk AW, Reijnders L (2000) Priority assessment of toxic substances in life cycle assessment. Part I: Calculation of toxicity potentials for 181 substances with the nested multi-media fate, exposure and effects model USES-LCA. Chemosphere 41:541–573CrossRefGoogle Scholar
- IAI (2015) Global Mass Flow Model. http://www.world-aluminium.org/publications/tagged/mass%20flow%20model/. Accessed 13 October 2015
- Payet J, Jolliet O (2002) Comparative assessment of the toxic impact of metals on aquatic ecosystems: the AMI method. International Workshop on Life-Cycle Assessment and Metals, pp 188–191Google Scholar
- Rosenbaum RK, Bachmann TM, Swirsky Gold L, Huijbregts MAJ, Jolliet O, Juraske R, Koehler A, Larsen HF, MacLeod M, Margni M, McKone TE, Payet J, Schuhmacher M, van de Meent D, Hauschild MZ (2008) USEtox—the UNEP/SETAC toxicity model: recommended characterisation factors for human toxicity and freshwater ecotoxicity in life cycle impact assessment. Int J Life Cycle Assess 13:532–546CrossRefGoogle Scholar
- Schecher WD, McAvoy DC (1998) MINEQL1—a chemical equilibrium modeling system, Ver 4.0. Environmental Research Software, HallowellGoogle Scholar
- Stumm W, Morgan JJ (1996) Aquatic chemistry. Wiley Interscience, New YorkGoogle Scholar