How Many Microbes Are Around Us: the Effects of Disinfectants and Soaps on the Growth of Microbial Colonies in Agar

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How many Microbes are Around us: The Effects of Disinfectants and Soaps on the Growth of Microbial Colonies in Agar INTRODUCTION The purpose of this study is to give us an idea of the quantity of microbes that we come in contact and interact with everyday. The secondary purpose of this study is to observe the effects of certain disinfectants and soaps on microbes grown in agar Petri dishes and determine their relative effectiveness. This will be done by three different methods of sampling and comparing the results. Fingers Test The first samples of the microbes were collected by the way of placing one's fingers on the half side of the Petri dish, then washing those same fingers with a soap or alcohol, and placing them on the other half side. The agents used to wash were "Softsoap", "Irish Spring" (bar soap), and Alcohol. Bench Test The second part of collecting the microbes was done by swabbing dust in various benches around the lab and placing it in the half side of the Petri dish. The area was then cleaned with a paper towel and a disinfectant ("Method" or Synosol), swabbed again and the sample was placed on the other half of the Petri dish. Time Test A third collection of microbes was done by letting the Petri dishes sit out in the open air at various locations in the lab over various periods of time. Control Test Various material used in the previous tests were also tested as controls. All samples collected in the Petri dishes from the three tests were incubated for several days. In accordance with common sense, the samples collected from the unwashed fingers and benches will exhibit the largest growth of microbial colonies, while the samples collected after the fingers and benches were washed with either soap or disinfectant will exhibit a lower growth. As for the time test, the Petri dishes exposed the longest to the open air will see

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