Price vs Quality – Comparing the Waterproof performance of mascaras

By Ellie Botham
Junior Category (Grades 7-8)
Experiment | Chemistry

The required ethics forms have been submitted for this project.

Many people wonder whether price is a good indicator of quality of cosmetics. In this experiment, waterproof mascaras were selected as an example cosmetic for testing. The hypothesis was that in comparing a variety of waterproof mascaras, more expensive waterproof mascaras would have better waterproof performance than cheaper waterproof mascaras.

The diameter of 140 strands of hair were measured using a technique involving measuring the size of diffraction pattern created when shining a laser over the hairs. 6 waterproof and 1 washable mascara were then applied to the hairs, and then the diameters were re-measured. The hairs were then washed using a Hair Washing Contraption to ensure consistent washing of all hairs. The hair diameters were measured for a third time, to determine the amount of mascara removed. Finally, Excel was used to analyze and compare the results using a statistical significance calculator with a probability coefficient p=0.05.

No statistically significant difference was found in the waterproof performance of the most expensive mascara which cost $43 and a mid-ranged priced mascara which cost $10. In some cases, cheaper mascaras were shown to be more waterproof than more expensive mascaras. Therefore, the hypothesis was not supported by the data; more expensive waterproof mascaras were not shown to have better waterproof performance than cheaper waterproof mascaras. Even though these results may not apply to all other kinds of cosmetics, this example proves a big conclusion: One cannot assume that price is an indicator of quality when it comes to makeup.

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