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Bacteriology Science Fair Project

Household Cleaners and Bacteria Removal

Hard
Household Cleaners and Bacteria Removal | Science Fair Projects | STEM Projects
What happens when you clean a chopping board with just water instead of bleach? The difference in leftover bacteria may surprise you. You cut fish on four plastic boards and let them sit for 30 minutes. Then you wash each board with a different cleaner. One gets plain water. Others get dish soap or Dettol or Clorox. You swab each board and grow the bacteria in petri dishes for five days. After five days you measure each bacteria colony to see which cleaner works best.

Hypothesis

The hypothesis is that Clorox is the most effective disinfectant, followed by Dettol.

Method & Materials

You will prepare agar petri dishes, use swabs to collect bacteria from used plastic chopping boards, and wash the chopping boards with different cleaning agents.
You will need 4 agar petri dishes prepared with blood agar, 4 disinfected swabs, 1 bottle of disinfected water, 4 used plastic chopping boards, tap water, 1 bottle dishwashing soap, 1 bottle of Dettol soap, 1 bottle of Clorox, 4 mackerel fish (or any other type of fish), 1 knife, and 1 marker pen.

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Results

The results showed that the chopping boards cleaned with Dettol solution and Clorox solution had the least amount of bacteria remaining on the surfaces. This proves that Clorox is the most effective disinfectant, followed by Dettol, and then the dish-washing soap.

Why do this project?

This science project is interesting because it tests the effectiveness of different cleaning agents in killing bacteria. It also shows the importance of using the right cleaning agent for the right job.

Also Consider

Experiment variations to consider include testing other cleaning detergents like antibacterial soap, Listerine or Bleach.

Full project details

Additional information and source material for this project are available below.

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