The purpose of this experiment is to discover any false-positives in common household foods and cleaning materials and test them with the presumptive tests phenolphthalein and hemastix. These tests are commonly used in Forensic Science to test for the presence or absence of blood, and any confirmed false-positives can help a criminalist determine what is present at a crime scene. It is expected that foods or substances that contain the enzyme peroxidase will be a false-positive when tested, the most commonly known in the Forensic Science field is horseradish peroxidase. The variables to be tested for this experiment include potato, sweet potato, tomato, broccoli, cucumber, cauliflower, mushroom, and celery. A number of household cleaners would also be tested, such as Lysol-brand cleaners, Chlorox bleach, 409, and Scentsy counter, bathroom and all-purpose cleaners, which the last three cleaners are plant based and contain citric acid. The last variable to be tested would be a rusty item, due to the fact that rust is formed from metal being oxidized and may provide a false-positive result. The testing methods available would be testing with sterile swabs, phenolphthalein solution, and the Hemastix swabs. In summary, testing for false-positives allows for more accurate testing of evidence of a crime and this type of research allows more criminalists in the Forensic Science field to work together to develop accurate presumptive tests.

Morgan Brown would like to thank their faculty sponsor Erik Hall for their support of this project.