title: The effect of pyrite on Escherichia coli in water: proof-of-concept for the elimination of waterborne bacteria by reactive minerals.
abstract: We present proof-of-concept results for the elimination of waterborne bacteria by reactive minerals. We exposed Escherichia coli MG1655 suspended in water to the reactive mineral pyrite (FeS₂) at room temperature and ambient light. This slurry eliminates 99.9% of bacteria in fewer than 4 hours. We also exposed Escherichia coli to pyrite leachate (supernatant liquid from slurry after 24 hours), which eliminates 99.99% of bacteria over the same time-scale. Unlike SOlar water DISinfection (SODIS), our results do not depend on the presence of ultraviolet (UV) light. We confirmed this by testing proposed SODIS additive and known photo-catalyst anatase (TiO₂) for antibacterial properties and found that, in contrast to pyrite, it does not eliminate E. coli under our experimental conditions. Previous investigations of naturally antibiotic minerals have focused on the medical applications of antibiotic clays, and thus have not been conducted under experimental conditions resembling those found in water purification. In our examination of the relevant literature, we have not found previously reported evidence for the use of reactive minerals in water sanitization. The results from this proof-of-concept experiment may have important implications for future directions in household water purification research.
authors.affiliation: Department of Geosciences, 255 Earth and Space Sciences (ESS) Building, Stony Brook University, Stony Brook, NY 11794-2100, USA E-mail: lonia.friedlander@stonybrook.edu.
authors.forename: Lonia R
authors.initials: LR
authors.lastname: Friedlander
authors.affiliation: Department of Biochemistry and Cell Biology and Center for Infectious Diseases, 5120 State University of New York, Stony Brook, NY 11794-5120, USA.
authors.forename: Neha
authors.initials: N
authors.lastname: Puri
authors.affiliation: Department of Geosciences, 255 Earth and Space Sciences (ESS) Building, Stony Brook University, Stony Brook, NY 11794-2100, USA E-mail: lonia.friedlander@stonybrook.edu.
authors.forename: Martin A A
authors.initials: MA
authors.lastname: Schoonen
authors.affiliation: Department of Biochemistry and Cell Biology and Center for Infectious Diseases, 5120 State University of New York, Stony Brook, NY 11794-5120, USA.
authors.forename: A
authors.initials: A
authors.lastname: Wali Karzai
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D058491:Bacterial Load; D002374:Catalase / Q000737:chemistry; D002614:Chelating Agents / Q000737:chemistry; D004203:Disinfection / Q000379:methods*; D004492:Edetic Acid / Q000737:chemistry; D004926:Escherichia coli / Q000187:drug effects*; D006861:Hydrogen Peroxide / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000494:pharmacology*; D013440:Sulfides / Q000494:pharmacology*; D014025:Titanium / Q000494:pharmacology; D014871:Water Microbiology; D014873:Water Pollutants; D018508:Water Purification / Q000379:methods*
chemical_list: D000900:Anti-Bacterial Agents; D002614:Chelating Agents; D013440:Sulfides; D014873:Water Pollutants; C011342:pyrite; C009495:titanium dioxide; D004492:Edetic Acid; D006861:Hydrogen Peroxide; D014025:Titanium; D007501:Iron; D002374:Catalase