Science Fair Expriment Antibacterial Hand Soap

Marketing Claims

When developing a science fair project it can be very helpful to look to the marketing campaigns of the household items that you use on a daily basis. The "scientific" claims that they make can be tested in your science fair projects. YOur project can be aimed at proving or disproving the validity of these marketing pitches.

PURPOSE

The purpose of this experiment was to compare the effect of anti-bacterial and non-anti-bacterial hand soap on the amount of bacteria on the hands.

I became interested in this idea when I was watching television and I saw ads for hand soaps that said they killed 99.9% of bacteria after washing your hands. I also wondered why my mom was so concerned about people washing their hands.

The information gained from this experiment could help doctors, nurses, parents, and children. No one wants to get sick! It is important to protect people from diseases.

HYPOTHESIS

My first hypothesis was that anti-bacterial hand soap would remove more bacteria than non-anti-bacterial hand soap.

My second hypothesis was that non-anti-bacterial hand soap would remove at least 50% of bacteria from the washed hands.

I based my hypotheses on a Compton’s Encyclopedia article on bacteria which said that one bacterium could produce over 1,000,000,000 more after 24 hours, and that not one hand soap could remove all bacteria from your hands.

EXPERIMENT DESIGN

The constants in this study were:
• The amount of time spent washing hands
• The motion of washing hands
• The approximate strength used to wash hands
• The amount of hand soap used (2 ml.)
• The temperature of the water
• The pressure of the water
• Time incubating
• The temperature of the incubator
• The number of blood agar plates used to culture bacteria

The manipulated variable was the type of hand soap: Anti-bacterial vs. Non-Anti-Bacterial

The responding variable was the number of colonies of bacteria on agar plates after being inoculated with samples from the hands.

To measure the responding variable, I counted the colonies of bacteria on the plates after they were incubated for 24 hours

MATERIALS

Scifair experiment antibacterial hand soap continues at antibacterial hand soap science fair projects.