Editing Arsenic (section)

=== Bioremediation ===

Physical, chemical, and biological methods have been used to remediate arsenic contaminated water.<ref name="JEM-2012">{{cite journal |last1=Jain |first1=C. K. |last2=Singh |first2=R. D. |title=Technological options for the removal of arsenic with special reference to South East Asia |doi=10.1016/j.jenvman.2012.04.016 |date=2012 |journal=Journal of Environmental Management |volume=107 |pages=1–8 |pmid=22579769|bibcode=2012JEnvM.107....1J |url=https://zenodo.org/record/1259107 }}</ref> Bioremediation is said to be cost-effective and environmentally friendly.<ref>{{cite journal |doi = 10.1007/s11270-013-1722-y |title = Bioremediation of arsenic-contaminated water: recent advances and future prospects |date = 2013 |last1 = Goering |first1 = P. |journal = Water, Air, & Soil Pollution |volume = 224 |issue = 12 |page=1722| bibcode = 2013WASP..224.1722B |s2cid = 97563539 }}</ref> Bioremediation of ground water contaminated with arsenic aims to convert arsenite, the toxic form of arsenic to humans, to arsenate. Arsenate (+5 oxidation state) is the dominant form of arsenic in surface water, while arsenite (+3 oxidation state) is the dominant form in hypoxic to anoxic environments. Arsenite is more soluble and mobile than arsenate. Many species of bacteria can transform arsenite to arsenate in anoxic conditions by using arsenite as an electron donor.<ref>{{cite journal |doi = 10.1016/j.jhazmat.2014.10.014| pmid = 25464303 |title = Anaerobic arsenite oxidation with an electrode serving as the sole electron acceptor: A novel approach to the bioremediation of arsenic-polluted groundwater. |date = 2015 |last1 = Goering |first1 = P. |journal = Journal of Hazardous Materials |volume = 283 |pages = 617–622| bibcode = 2015JHzM..283..617P | hdl = 10256/11522 }}</ref> This is a useful method in ground water remediation. Another bioremediation strategy is to use plants that accumulate arsenic in their tissues via [[phytoremediation]] but the disposal of contaminated plant material needs to be considered.

Bioremediation requires careful evaluation and design in accordance with existing conditions. Some sites may require the addition of an electron acceptor while others require microbe supplementation ([[bioaugmentation]]). Regardless of the method used, only constant monitoring can prevent future contamination.