Fate of Silver Biocide on the International Space Station Living Environment



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50th International Conference on Environmental Systems


Preventing microbial growth within crewed spacecraft water systems is a primary concern to ensure the health and safety of the crew and protect onboard equipment. Silver is being considered by NASA as a biocide replacement for iodine in the International Space Station (ISS) water system. Iodine is currently used but must be removed from the water before crew consumption due to health concerns related to iodine absorption. Aboard the ISS, several systems currently utilize silver as a biocide, including the Russian Orbital Segment (ROS) water system, which incorporates silver ions, and the US Orbital Segment (USOS) heat exchangers, which utilize a silver salt to prevent microbial development. A recent collection of airborne particles on the ISS showed the presence of silver particles, motivating an investigation into their source and the possibility of their unintentional escape into the air. As the ISS is a closed system, it is vital to determine the composition and concentration of potentially harmful particles in the environment. This paper concerns a literature review conducted to further understand the fate of silver biocide in space and, more specifically, aboard the ISS.


Sarah Ley, University of Minnesota
Wenyan Li, URS Federal Services
Amanda Rodell, NASA KSC Internship Program
Marit Meyer, NASA
Luz Calle, NASA
Traci Lersch, RJ Lee Group
Kristin Bunker, RJ Lee Group
Gary Casuccio, RJ Lee Group
ICES303: Physio-Chemical Life Support- Water Recovery & Management Systems- Technology and Process Development
The 50th International Conference on Environmental Systems was held virtually on 12 July 2021 through 14 July 2021.


silver, water, biocide, ISS, air