Isolation of Microbes From Common Household Surfaces

Microorganisms are ubiquitous in nature. One might think that one is safe from these microorganisms at home, but they can be found there, too, especially in areas where food is prepared. It is common practice to clean food and food products prior to consumption. However, it is equally important to sanitize the places where food is stored and prepared, and also to sanitize the locations and items commonly used within a typical house. This work systematically investigated the occurrence of a variety of microorganisms on common household items and places. We hypothesized that a variety of microorganisms (e.g. bacteria and fungi) would be found from common household surfaces, even when those surfaces are regularly cleaned, and that a strong disinfecting agent, such as ethanol (70%) should eliminate the majority of these microorganisms. The appearance of microorganisms was observed on nutrient agar plates which were swabbed with samples from seven different sites in a house (kitchen counter, kitchen sink, bathroom floor, toilet seat, window, dishwasher, and bathtub) under non-sterile conditions, and the microbial load was observed to be significantly diminished after the surfaces were cleaned with 70% ethanol. We conclude that 70% ethanol based sanitation is of utmost importance to be safe at home.