Toxicity of Trace Metals in Soil as Affected by Soil Type and Aging After Contamination: Using Calibrated Bioavailability Models to Set Ecological Soil Standards
- 1 August 2009
- journal article
- research article
- Published by Wiley in Environmental Toxicology and Chemistry
- Vol. 28 (8), 1633-1642
- https://doi.org/10.1897/08-592.1
Abstract
Total concentrations of metals in soil are poor predictors of toxicity. In the last decade, considerable effort has been made to demonstrate how metal toxicity is affected by the abiotic properties of soil. Here this information is collated and shows how these data have been used in the European Union for defining predicted-no-effect concentrations (PNECs) of Cd, Cu, Co, Ni, Pb, and Zn in soil. Bioavailability models have been calibrated using data from more than 500 new chronic toxicity tests in soils amended with soluble metal salts, in experimentally aged soils, and in field-contaminated soils. In general, soil pH was a good predictor of metal solubility but a poor predictor of metal toxicity across soils. Toxicity thresholds based on the free metal ion activity were generally more variable than those expressed on total soil metal, which can be explained, but not predicted, using the concept of the biotic ligand model. The toxicity thresholds based on total soil metal concentrations rise almost proportionally to the effective cation exchange capacity of soil. Total soil metal concentrations yielding 10% inhibition in freshly amended soils were up to 100-fold smaller (median 3.4-fold, n = 110 comparative tests) than those in corresponding aged soils or field-contaminated soils. The change in isotopically exchangeable metal in soil proved to be a conservative estimate of the change in toxicity upon aging. The PNEC values for specific soil types were calculated using this information. The corrections for aging and for modifying effects of soil properties in metal-salt-amended soils are shown to be the main factors by which PNEC values rise above the natural background range.Keywords
This publication has 36 references indexed in Scilit:
- INFLUENCE OF SOIL PROPERTIES ON COPPER TOXICITY FOR TWO SOIL INVERTEBRATESEnvironmental Toxicology and Chemistry, 2008
- Phytotoxicity of nickel in a range of European soils: Influence of soil properties, Ni solubility and speciationEnvironmental Pollution, 2007
- Long-term exposure to elevated zinc concentrations induced structural changes and zinc tolerance of the nitrifying community in soilEnvironmental Microbiology, 2006
- Development and validation of an acute biotic ligand model (BLM) predicting cobalt toxicity in soil to the potworm Enchytraeus albidusSoil Biology and Biochemistry, 2006
- Soil properties affecting the toxicity of CuCl2 and NiCl2 for soil microbial processes in freshly spiked soilsEnvironmental Toxicology and Chemistry, 2006
- Deriving Soil Critical Limits for Cu, Zn, Cd, and Pb: A Method Based on Free Ion ConcentrationsEnvironmental Science & Technology, 2004
- Importance of contamination history for understanding toxicity of copper to earthworm Eisenia fetica (Oligochaeta: Annelida), using neutral‐red retention assayEnvironmental Toxicology and Chemistry, 2000
- Is soil acidification the cause of biochemical responses when soils are amended with heavy metal salts?Soil Biology and Biochemistry, 1999
- Toxicity of heavy metals to microorganisms and microbial processes in agricultural soils: a reviewSoil Biology and Biochemistry, 1998
- Metal speciation. Effects on aquatic toxicityEnvironmental Science & Technology, 1980