Science Fair Lab Report

Dying to Know

Jenn Greiner

Starleene Thou

Honors Chemistry

Ms. Chan

January 20, 2015

Table of Contents

Abstract

Problem…………………………………………………………………………...….……1

Background Research……………………………………………………………………..1

Hypothesis…………………………………………………………………………………4

Materials and Equipment………………………………………………………….....……5

Procedures……………………………………....................................................................6

Data Tables and Graphs………………………...................................................................8

Analysis/Discussion……………………………………………………………….…..…10

Conclusion………………………………………………………………………….……11

Bibliography…………………………………………………………………………..…13

Abstract

As 75% of American women dye their hair, this brings up interests as to which color hair

dyes are most damaging to their hair. This experiment tests which color hair dyes cause

the most damage/breakage to hair strands. The scientists hypothesized that if hair dye

color is related to the damage of hair, then lighter colored hair dyes will have a greater

damaging effect on hair. The independent variable in this experiment was the color of the

hair dye; the dependent variable was the damage caused to the hair. The controls for this

experiment are the latex gloves, hair samples, shower, aluminum foil, cup, shampoo,

conditioner, hair brush, book, scientists and testing environment that remained consistent

throughout the experiment.

This experiment was carried out by using hair loss as a means to determine overall

damage. A medium sized hair brush was used to brush the samples of dyed hair ten times,

with a heavy book placed on top to hold it down. The number of hair strands that had

fallen out of the hair sample and onto the brush were counted and recorded. This process

was done for each different hair sample for three trials.

In this experiment it was found that the control had the least amount of hair breakage

when brushed with an average of 1.6 broken strands. The next least breakage was that of

the hair samples dyed black with an average of 2.3 broken strands. Next, came the hair

samples dyed brown which had an average of 3 broken strands. Then, came the hair

samples dyed auburn with an average of 5.3 broken strands. The hair dye that caused the

most amount of damage was the blonde hair dye which had an average of 6 broken

strands from being brushed.

The conclusion of this experiment is that the scientist’s hypothesis was accepted, the

lighter hair dyes caused more damage to the hair than the darker hair dyes. This

conclusion was formed considering that on average, the auburn and blonde hair dyes (the

lighter hair dyes) caused more strands of hair to break than the black and brown hair dyes

(the darker hair dyes). One issue from this experiment was that it had the uncontrolled

variable of human error brushing each strand of hair. This uncontrolled variable was

countered with the human carefully ensuring that each stroke was the same for each

strand and followed the procedure exactly. An application of this project would be to

create a scale of how much damage each color is likely to cause to hair, and require the

rating to be put on the hair dye box. This would warn buyers about the harmful effects of

the dye and may affect their color choice. One extension of this investigation would be to

also test semi-permanent hair dyes and see if the experiment still produces the same

results of the lighter hair dyes causing more damage. Another extension of this

investigation would be to test different brands of hair dyes and see if the results were the

same as in this experiment.

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Problem

Problem Statement: How does the color of hair dye affect how much damage it causes to

hair?

Background Research

These scientists first began by researching about the structure of human hair. The hair

shaft is where the dying takes place. This is the part of the hair that is seen (above the

skin) and is made up of dead cells that turned into keratin. The hair shaft formed of three

layers which are the medulla, the cortex, and the cuticle. The medulla is the deepest layer

and is only seen in large and thick hairs. The cortex is the middle layer which is

responsible for determining the strength, color and texture of the hair. It is in the cortex

that the process of hair dying takes place. The outer layer is the cuticle which is thin and

colorless and serves to protect the cortex. The ammonia in hair dye relaxes and lifts up

the cuticle in order to get to the cortex, the initial lifting of the cuticle is damaging alone.

("FUE Hair Transplant Clinic in London")

The scientists then went into deeper research about hair dyes and the damaging effects

that they have on hair (the dependent variable). There are three main types of hair dyes;

temporary hair colorants, semi-permanent hair colorants, and oxidation hair colorants. In

this experiment, the oxidation hair colorants, also known as permanent hair dyes, will be

used. Oxidation hair colorants utilize an alkaline agent and oxidizing coloring agents. The

alkaline agent opens up the outer layer of hair to allow easier access to the inner hair

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shaft. The oxidizing and coloring agents then lighten and pigment the hair color to

effectively replace the natural color. These effects are resistant to washing out and in turn

last longer, hence “permanent’.

Some permanent hair dyes include chelants, which are added to the formula in order to

stabilize hydrogen peroxide. Because hair also includes copper and other such metals, the

chelants may react with the hair, forming free radicals that have damaging effects. (Julie

McManus, Hair Colorants: How Do Hair Colorants Work?)

Other damaging effects of strong hair dyes include drying out, destruction of nutrients

and healthy oils, and split ends. These effects are caused by the harsh chemicals found in

the dyes, such as ammonia and peroxide. Ammonia (a colorless, pungent gas) can be

found in certain fertilizers and disinfectants. Peroxide is used as the bleaching agent in

the hair dyes. (Jenny Tai, Hair Dye and Hair Bleach: How Do They Work?). Repeated

use of harsh chemicals and the application of any chemical to the hair has implications

for damaging effects.

Lightening hair dye also works different from darkening hair dye. Lightening hair dye

uses bleach or peroxide to remove the existing pigment. The existing pigment called

melanin is located in the cortex of the hair so ammonia and peroxide are used to penetrate

the cuticle of the hair to get to the cortex to strip and deposit color. Using too much

peroxide is called over processing and can be damaging to the hair shaft. ("8 commonly

asked questions about coloring your hair") When dying your hair lighter, the hair first has

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to be bleached, and then the ammonia and peroxide in the dye create and deposit color in

the hair shaft. If you’re dying your hair darker than its natural color then the dye uses the

interaction between the ammonia and peroxide to create a new color in your hair shaft

without the extra step of stripping the color. (Brain, M., "Hair Dye")

This project has real world application since today 75% of American women color their

hair. Men also dye their hair resulting in $113.5 million in Men’s home hair-color sales in

2013. In 2013, about 76% of people who dyed their hair already knew that hair dying was

unsafe. 13.5% of people believed that permanent hair dyes were safe (“Trends in Use of

Hair Dye: A Cross-Sectional Study”). In conclusion, these scientists have learned about

how hair dyes work, their damaging effects, and the real world application of the

experiment.

4

Hypothesis

If hair dye color is related to the damage of hair, then lighter colored hair dyes will have a

greater damaging effect on hair because lighter hair dyes contain harmful bleaches that

dry out hair and the darker dyes do not.

5

Materials and Equipment

● Garnier Nutrisse Nourishing Color Creme 1 box of each of the following colors:

100-Extra Light Natural Blonde, 20- Soft Black, 76- Rich Auburn Blonde, and 53-

Medium Golden Brown

● Latex gloves (2 pairs)

● 15 samples of six inch ProExtensions Dark Golden Blonde hair extensions

● A shower

● A 12 inch by 30 inch sheet of aluminum foil

● A 16 ounce disposable plastic cup

● A 13 ounce bottle of Garnier Fructis Color Shield Complete Defense Shampoo

● A 13 ounce bottle of Garnier Fructis Color Shield Complete Defense Conditioner

● A medium hair brush

● A moderately heavy book

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Procedures

1. Gather all of the materials inside of a bathroom where the shower is located.

2. Mix the nourishing color creme with the nourishing creme developer inside of the

developer bottle as instructed by the directions on the hair dye box. Do this for

each of the 4 colors.

3. Using latex gloves, use the hair dye to color 3 samples of hair by combing the dye

through each samples with your fingers. Repeat this for each of the colors. Leave 3

samples undyed for a control.

4. Allow dye to sit for directed time of 15 minutes. Use 1 drop of the conditioner that

comes with the box kit of hair dye and fresh water from the shower to rinse out the

hair samples until the water runs clear off of the sample. Repeat this for each of

the dyed samples.

5. Lay out each hair sample to dry on the sheet of aluminium foil, leaving 1 inch of

space in between each sample. Wait 1 hour allowing each sample to dry

completely.

6. Secure a hair sample on the edge of a surface, using the book as a weight to hold

the top down. Use the hair brush to brush the sample 10 times. Count the number

of hair strands that has fallen out of the sample and onto the brush. Record data.

7. Repeat step 6 for each sample of hair of a different color including the control

sample. Once a sample of each different color has been tested, perform 2 more

trials. Continue to record data.

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8. Analyze the recorded data and compare the amount of hair that each sample lost.

The sample that lost the most hair had the most damage. The hair that lost the least

hair was less damaged. Use this comparison to form a conclusion of which hair

dye causes the most damage to hair.

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Data Tables and Graphs

Pictures from the experiment:

Data Table from the experiment:

Effect of Hair Dye Color on Hair Breakage

*Number of Hair Strands Lost*

Control Blonde Auburn Brown Black

Trial 1 1 5 4 4 2

Trial 2 2 6 6 3 2

Trial 3 2 7 6 2 3

Average 1.666666667 6 5.333333333 3 2.333333333

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Graphs:

0

1

2

3

4

5

6

7

Control Blonde Auburn Brown Black

Nu

mb

er

of

Hai

r St

ran

ds

Lost

Hair Dye Color

Hair Dye Affect on Hair Breakage Average

Control

Blonde

Auburn

Brown

Black

Hair samples that were dyed with lighter colors lost more hair than the samples that were dyed with darker colors.

0

1

2

3

4

5

6

7

8

Trial 1 Trial 2 Trial 3

Nu

mb

er

of

Hai

r St

ran

ds

Lost

Trial Numer

Hair Dye Affect on Hair Breakage

Control

Blonde

Auburn

Brown

Black

The hair samples that were dyed with lighter colors lost more hairthan the samples dyed with darker colors.

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Analysis/Discussion

During this experiment, the damage done to the samples of dyed hair was observed. After

dyeing the hair with their respective colors and letting them dry, these scientists carried

out the experiment. The control sample lost 1 strand of hair in the first trial, 2 strands in

the second trial, and 2 strands in the third trial. The blonde hair sample lost 5 strands of

hair in the first trial, 6 strands in the second, and 7 strands in the third trial. The auburn

hair sample lost 4 strands of hair in the first trial, 6 strands in the second, and 6 strands in

the third trial. The brown hair sample lost 4 strands of hair in the first trial, 3 strands in

the second trial, and 2 strands of hair in the third trial. The black hair sample lost 2

strands of hair in the first trial, 2 strands in the second trial, and 3 strands in the third trial.

The order of the dyes, by amount of damage caused from least to greatest, is control,

black, brown, auburn, then blonde. This pattern is consistent within the three trials, with

an exception in the third one. In the third trial, the black hair had lost more strands than

the brown hair. This data is consistent enough to conclude that lighter colored dyes

damages hair more than darker colored dyes. The data collected for the control samples

seemed out of place. The numbers for the controlled hair samples were unusually low,

ranging from loss of only 1-2 strands of hair per trial. This is due to the fact that these

samples were not treated with any chemicals or dyes, therefore were the most “healthiest”

and least likely to lose hair due to damage. The numbers for the control samples serve as

a basis to make conclusions about the other hair samples.

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Conclusion

The scientists’ hypothesis was that if hair dye color is related to the damage of hair, then

lighter colored hair dyes will have a greater damaging effect on hair. This hypothesis was

supported by the data. This is because the lighter hair dyes being blonde and auburn

caused more hair strand breakage than the darker hair dyes being brown and black. The

control hair had the least hair breakage (an average of 1.6 pieces) due to the fact that

there was no harmful dying which involves the lifting up if the hair shaft. The black dye

caused the next least breakage (an average of 2.3 pieces). Next, came the brown dye (an

average of 3 broken pieces). Then, the auburn hair dye (an average of 5.3 broken pieces).

And the hair dye that caused the most damage was blonde (an average of 6 pieces).

These results are due to the fact that the lighter colors had to strip the hair of its existing

color and then the color is deposited in the hair’s cortex. The darker hair dyes do not have

to bleach the hair first and instead just add color over the existing color. Therefore, the

lighter hair dyes caused more damage than the darker hair dyes since they contain the

harmful bleach that strips the hair of its natural color.

One problem with this experiment was making sure that each hair sample was dyed in

the same procedure, with each one getting evenly coated in their respective colors. This

might affect our experiment because if each of the samples is not dyed in the same

manner, then that inconsistency may prove as an uncontrolled variable. Another thing

that may have affected our experiment is the fact that a human brushed the hair. This

could have affected the results because even though each of the hairs was brushed the

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same number of times in a controlled manner, there is still a chance of human error of

different speeds and force.

This experiment could be improved in many ways. One way would be to get rid of the

human variable. It would be ideal to find a way to brush the hair without the use of

people, maybe by the use of a mechanicalism. This mechanicalism or method or more

precise measuring could also be used in the hair dying process.

This use of mechanicalism would be helpful since it would eliminate the uncontrolled

variable of human error. A mechanical or more precise way of dying the hair would allow

it to be dyed the same exact way for each sample to ensure that they have the same exact

amount of dye. This would eliminate this human variable and increase the validity of the

experiment. The use of mechanicalism as a way to brush the hair would be helpful since

it would ensure that each sample of hair is brushed the same exact way each time. This

would eliminate the human error of brushing the hair differently. It would ensure that

every stroke is the same so that way the experiment itself is controlled and the way the

hair is brushed would not change the amount of hair that comes out from sample to

sample. An additional further experiment that could be performed in order to investigate

the experiment further would be to test if the color of hair dye in semi-permanent dyes

still affects the amount of damage they cause to hair. Another additional experiment that

could be performed to further investigate the question would be to test different brands of

hair dyes and see if the results were the same as in this experiment.

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Bibliography

1. 8 commonly asked questions about coloring your hair. (n.d.). Retrieved November

30, 2014, from http://www.empire.edu/blog/cosmetology-how-tos/8-commonly-

asked-questions-about-coloring-your-hair

2. Brain, M. :Hair Dye”. (n.d.). Retrieved November 30, 2014, from

http://science.howstuffworks.com/innovation/everyday-innovations/hair-

coloring7.htm

3. FUE Hair Transplant Clinic in London. (n.d.). Retrieved November 30, 2014,

from http://www.hshairclinic.co.uk/hair-loss/all-about-hair/hair-structure/

4. McManus, Julie. "Hair Colorants: How Do Hair Colorants Work?" CTPA. Web.

30 Nov. 2014. <http://www.ctpa.org.uk/document.aspx?fileid=1389>.

5. Patel, Dharmistha, Sarala Narayana, and Bhuvana Krishnaswamy. “Trends in Use

of Hair Dye: A Cross-Sectional Study.” International Journal of Trichology5.3

(2013): 140–143. PMC. Web. 30 Nov. 2014.

6. Styles and lengths. (n.d.). Retrieved January 19, 2015, from

http://www.realhairexclusive.com/natural-and-processed-hair

7. Tai, Jenny. "Hair Dye and Hair Bleach: How Do They Work?" - SiOWfa12:

Science in Our World: Certainty and Controversy. 19 Sept. 2012. Web. 30 Nov.

2014. <http://www.personal.psu.edu/afr3/blogs/siowfa12/2012/09/hair-dye-and-

hair-bleach-how-do-they-work-1.html>.