The Effects of Chemical and Thermal Treatments on Hair Strength Xenia Chiru Moscrop Secondary Floor Location : J 125 H

Summary Statement: This project is about the effects of chemical and thermal treatments on hair strength.

Objective: The objective of this project was to determine which hair treatment affects the hair?s strength most. The hypothesis was that the hair which isn?t chemically treated (henceforth called ?normal? hair) will be the strongest, the hair that is dyed black the second strongest, the straightened-normal hair the third strongest, the hair that is dyed blond the fourth strongest, the straightened-black hair the fifth strongest, and the straightened-blond hair the weakest.

Materials and Method: The main materials used in this experiment were a hair straightener, permanent light blond hair dye, permanent black hair dye, weights, a scale, and about 150 brown hairs. The procedure was: It was made sure that all the hairs were 30 cm, and then they were lifted by the ends. The weights were then added the weights, until the hair ruptured. One hair at a time was tested. The weights were small sandbags of 20g, 5g, or 1g with a little hook at the top.

Results: The normal hair was found to be the strongest, followed by the black hair, the blond hair, the straightened- normal hair, the straightened-colored black hair, and the straightened-colored blond hair.

Conclusion/Discussion: The results of this experiment were not surprising. They indicated that chemically and thermally treated hair does get damaged and is weaker than normal hair. Although the experiment was not carried out in a fully equipped science lab with the best technology available, it is thought that the results are still valid, conclusive, and they merit discussion. Owing to its structure, hair strand is fragile and successive treatments can harm it. This is important to know for makers of hair dye and, of course, for us consumers. Everybody must know that when we choose to treat our hair we must be informed and cautious. If this matter could be pursued further, I would like to see the treated hair strand under a microscope and compare it to a normal hair strand. Also, it would be interesting to try the same experiment for hair that has been treated several times in the past, since the hair that used in this experiment had never been treated before, and to find out if conditioners and shampoos meant only for colored\treated hair really make the treated hair stronger than regular shampoo.