Yeast catalysis of hydrogen peroxide as an enhanced chemical treatment method for harvested rainwater

Rainwater is frequently collected at home for many reasons, so household methods of rainwater treatment are necessary for convenience. Usually, the chlorination process with hypochlorite (ClO^-) bleach is used, but hydrogen peroxide (H₂O₂) has been proposed as a home treatment method. Catalyzed H₂O₂ treatment is already used for wastewater pollution, so it may also be applied to harvested rainwater. A home-accessible catalyst is yeast. This study aimed to investigate whether catalyzed H₂O₂ treatment is a viable way to chemically treat home-collected rainwater. Our main hypothesis was that H₂O₂ would decrease concentrations of chemical contaminants more effectively than ClO^- due to its stronger oxidation capabilities and catalysis would quicken treatment speed. Rainwater samples were treated with varying concentrations of ClO^-, pure H₂O₂, or yeast-catalyzed H₂O₂. We assessed the samples with pH probes, dissolved oxygen (DO) probes, and chemical contaminant test strips before, during, and after treatment. We found that in terms of pH, ClO^- treated water the most effectively, bringing the pH closest to 7; but in terms of DO, yeast-catalyzed H₂O₂ treatment was the most effective, resulting in the healthiest DO levels. The test strips assessing chemical contaminants had uncertainties too high to form many conclusions. Therefore, either chlorination or yeast-catalyzed H₂O₂ treatment show potential as the best methods investigated for home rainwater treatment, but further research is needed to assess their effects on specific contaminants. These findings imply that yeast-catalyzed H₂O₂ treatment could be a novel method of home rainwater treatment that is both cost-effective and eco-friendly.