Biomineralisation of metals in soil – effect of metal toxicity and precipitation as a protective mechanism

Mugwar, Ahmed and Harbottle, Michael John ORCID: https://orcid.org/0000-0002-6443-5340 2014. Biomineralisation of metals in soil – effect of metal toxicity and precipitation as a protective mechanism. Presented at: 7th International Congress on Environmental Geotechnics, Melbourne, Australia, 9-14 November 2014. Published in: Bouazza, Abdelmalek, Yuen, Sam and Brown, Bruce eds. Proceedings of the 7th International Congress on Environmental Geotechnics. Engineers Australia, pp. 1136-1142.

Preview

PDF - Accepted Post-Print Version Download (460kB) | Preview

Abstract

Biomineralisation offers the potential for in-situ sequestration and subsequent reduction in the bioavailability of heavy metals and radionuclides in the subsurface environment. Calcium carbonate minerals are known to sorb and form solid solutions with a range of target elements, and are readily produced by the actions of common microorganisms on simple chemical precursors. The ability of a commonly used urea-degrading, calcium carbonate-precipitating bacterium, Sporosarcina pasteurii, to tolerate the presence of a model contaminant, strontium, was determined in aqueous solution, with reduction in growth only seen at concentrations of 10 mM. Its ability to remove strontium from solution via calcium carbonate precipitation was then determined, and here S. pasteurii was shown to be able to remove 99% (+/- 1%) strontium from solution at concentrations up to 30 mM. This suggests that biomineralisation of metallic elements may afford a protective mechanism for the bacteria through providing a means to reduce the overall concentrations to tolerable levels. Finally, we explored the effects of ground conditions on mineralisation and strontium sequestration in different sand fractions (fine, medium and coarse), in a series of batch experiments. Almost all (97-99%) strontium present was removed from aqueous solution after three days, whereas no precipitation was observed in control samples over the same period. The amount of strontium removed increased with coarseness of sand grains under these static conditions, although over a very small range.

Item Type:	Conference or Workshop Item (Paper)
Date Type:	Publication
Status:	Published
Schools:	Engineering
Subjects:	T Technology > TA Engineering (General). Civil engineering (General) T Technology > TD Environmental technology. Sanitary engineering
Publisher:	Engineers Australia
ISBN:	9781922107237
Funders:	Iraqi Ministry of Higher Education and Scientific Research
Date of First Compliant Deposit:	30 March 2016
Last Modified:	28 Oct 2022 08:51
URI:	https://orca.cardiff.ac.uk/id/eprint/72382

Actions (repository staff only)

Edit Item