How different Types of Soap Affect Algae Growth

Our objective was to find out how ECO-Plus Hand Dishwashing Liquid, soap claimed to be safe for the environment, would effect the growth of algae, when compared to Palmolive Dishwashing Liquid, a standard soap. We setup our experiment by filling three tubs with 8000 mL of water and adding .25 mL of Palmolive to one, .25 mL of ECO-Plus to another and leaving the last one as a control. We took three samples from each tub tri-weekly for five weeks. Using the Lab Pro, colorimeter and a TI-83 Plus Calculator, we tested the turbidity, light absorbance, of each sample. We then calculated the average turbidity of the water in each tub. Using the averages we graphed our data for descriptive data interpretation. This showed that Palmolive had the most algae growth, ECO-Plus had the second most algae growth and the control had the least amount of algae growth. For further data analysis we used all the original data points to run three two-sample t-tests. One test compared the Control to Palmolive, one compared Control to ECO-Plus and one compared ECO-Plus to Palmolive. With 95% confidence we found our data was probably due to chance, and we could not make any valuable or significant conclusions about how safe these soaps were for the environment.

Research Done By:

Johanna Scheer
Warren Mott

Melissa Szymanski
Sterling Heights