Environmental Toxicology

Aquatic toxicity of magnesium sulfate, and the influence of calcium, in very low ionic concentration water

  1. Rick A. van Dam1,*,
  2. Alicia C. Hogan1,
  3. Clint D. McCullough2,
  4. Melanie A. Houston1,
  5. Chris L. Humphrey1,
  6. Andrew J. Harford1

Article first published online: 4 NOV 2009

DOI: 10.1002/etc.56

Issue

Environmental Toxicology and Chemistry

Environmental Toxicology and Chemistry

Volume 29, Issue 2, pages 410–421, February 2010

Additional Information

How to Cite

van Dam, R. A., Hogan, A. C., McCullough, C. D., Houston, M. A., Humphrey, C. L. and Harford, A. J. (2010), Aquatic toxicity of magnesium sulfate, and the influence of calcium, in very low ionic concentration water. Environmental Toxicology and Chemistry, 29: 410–421. doi: 10.1002/etc.56

Author Information

  1. 1

    Environmental Research Institute of the Supervising Scientist, Supervising Scientist Division, Australian Government Department of the Environment, Water, Heritage and the Arts, P.O. Box 461, Darwin, Northern Territory 0801, Australia

  2. 2

    Edith Cowan University, Centre for Ecosystem Management, Joondalup, Western Australia 6027, Australia

*Environmental Research Institute of the Supervising Scientist, Supervising Scientist Division, Australian Government Department of the Environment, Water, Heritage and the Arts, P.O. Box 461, Darwin, Northern Territory 0801, Australia.

Publication History

  1. Issue published online: 21 JAN 2010
  2. Article first published online: 4 NOV 2009
  3. Accepted manuscript online: 4 NOV 2009 12:00AM EST
  4. Manuscript Accepted: 8 SEP 2009
  5. Manuscript Revised: 17 AUG 2009
  6. Manuscript Received: 2 JUN 2009
Corrected by:

Erratum: Erratum: Aquatic toxicity of magnesium sulfate, and the influence of calcium, in very low ionic concentration water

Vol. 29, Issue 5, 1199, Article first published online: 14 APR 2010

SEARCH

SEARCH BY CITATION

ARTICLE TOOLS

View Full Article (HTML) Get PDF (179K)

Keywords:

  • Magnesium;
  • Toxicity;
  • Calcium;
  • Sulfate;
  • Water quality guidelines

Abstract

The toxicity of magnesium sulfate (MgSO4), and the influence of calcium (Ca), were assessed in very soft freshwater (natural Magela Creek water [NMCW]) using six freshwater species (Chlorella sp., Lemna aequinoctialis, Amerianna cumingi, Moinodaphnia macleayi, Hydra viridissima, and Mogurnda mogurnda). The study involved five stages: toxicity of MgSO4 in NMCW, determination of the toxic ion, influence of Ca on Mg toxicity, toxicity of MgSO4 at an Mg:Ca mass ratio of 9:1, and derivation of water quality guideline values for Mg. The toxicity of MgSO4 was higher than previously reported, with chronic median inhibition concentration (IC50)/acute median lethal concentration (LC50) values ranging from 4 to 1,215 mg/L, as Mg. Experiments exposing the 3 most sensitive species (L. aequinoctialis, H. viridissima, and A. cumingi) to Na2SO4 and MgCl2 confirmed that Mg was the toxic ion. Additionally, Ca was shown to have an ameliorative effect on Mg toxicity. For L. aequinoctialis and H. viridissima, Mg toxicity at the IC50 concentration was eliminated at Mg:Ca (mass) ratios of ≤10:1 and ≤9:1, respectively. For A. cumingi, a 10 to 30% effect persisted at the IC50 concentration at Mg:Ca ratios <9:1. The toxicity of MgSO4 in NMCW at a constant Mg:Ca ratio of 9:1 was lower than at background Ca, with chronic IC50/acute LC50 values from 96 to 4,054 mg/L, as Mg. Water quality guideline values for Mg (to protect 99% of species) at Mg:Ca mass ratios of >9:1 and ≤9:1 were 0.8 and 2.5 mg/L, respectively. Magnesium can be toxic at concentrations approaching natural background levels, but toxicity is dependent on Ca concentrations, with exposure in very low ionic concentration, Ca-deficient waters posing the greatest risk to aquatic life. Environ. Toxicol. Chem. 2010;29:410–421. Published 2009 SETAC

View Full Article (HTML) Get PDF (179K)