Deuterium-depleted water (DDW), also known more ambiguously as light water, is water which has a lower concentration of deuterium than occurs naturally. Deuterium a heavier isotope of hydrogen which has, in addition to its one proton, a neutron, that roughly doubles the mass of the hydrogen atom.
In Vienna Standard Mean Ocean Water, deuterium occurs at a rate of 155.76 ppm. The production of heavy water involves isolating and removing deuterium within water. The by-product of this process is light water. Production of light water can result during electrolysis, distillation, and desalination. Filtration through special membranes and crystallization are also considered preparation methods. It can also be produced directly using the Girdler sulfide process.
Experiments have looked at drinking light water in addition to chemotherapy in cancer. Research on the effects of deuterium-depletion on living cells has been very limited with less than a dozen peer-reviewed research papers available via PubMed in mid-2011.
Depleted water (125 ppm deuterium corresponds to the deuterium:protium ratio D:H=1:7695) at a consumption as high as 2 litres per day can influence the deuterium concentration in human body (average 40 litres with deuterium:protium ratio about D:H = 1:6418) for less than 1% (decreasing the normal ratio to D:H = 1:6472). A 1963 American paper is reported to infer that no biological effect should be expected at this level.
- Boyle, Rebecca (January 6, 2011). "With New Method, China Can Mass-Produce Light Water For Its Citizens' Thirst". Popular Science. Retrieved January 7, 2011.
- Barishev, M. G.; Dzhimak, S. S. (February 2013). "International Journal of Engineering Research and Applications". 3 (1): 523–526. ISSN 2248-9622.
- Koch, Steven J. (4 March 2011). "I am maximally-skeptical that there currently exists any evidence that drinking deuterium-depleted water has health benefits or will cure disease". Blogspot.com. Retrieved 22 July 2011.
- Thompson, J. F. (1963), Biological effects of deuterium, New York: Pergamon Press