What’s in your water?
By Abigail Hope Marchetti
STUDENT
INTRODUCTION
Hi, my name is Abigail Hope Marchetti. I am
a homeschooled 8th Grader. I take the
Physical Science course in FLVS, and I
recently finished an M/J Keyboarding course.
My Mom wanted my brother and me to be a
part of the Science Fair since we were taking
a science course. I am excited about
participating in the Science Fair! This will be
an interesting experience for me since I have
never
been in a Science Fair before and since this is online. I am curious as to what it
will be like. I hope you will enjoy my project. I have learned a lot of valuable
things from doing this science experiment!
PROJECT
INTRODUCTION
I wanted to do this experiment, What’s In Your Water?, because I
thought it would be interesting and fun. This experiment provides
a way for families to make the healthiest choice of which water to
drink. My family drinks Glacier water, and it tastes better than any
water I’ve ever drank. Since it tastes much more delicious than
any of my friends’ water or bottled water, I thought that it had the
least amount of mercury, arsenic, and lead. It’s important for
families to have the cleanest water possible, since a large amount
of our bodies is made up of water! If you have ever heard a
doctor tell you to drink eight glasses of water a day, you will see
how important it is to be drinking eight glasses of the right water!
What’s in your water?
My hypothesis: If six different kinds of bottled water, tap water,
and home-purified water are compared for how much mercury,
arsenic, and lead are in them, then Glacier water will be the
healthiest, concerning metals.
My purpose: My purpose is to find out which water is the
healthiest concerning the amount of mercury, arsenic, and lead in
each.
HYPOTHESI
S
If six different kinds of water are tested for how much mercury, arsenic,
and lead are in them, then Glacier water will have the least amount of
these contaminants.
INITIAL RESEARCH
I searched for a nearby water plant, and I found the South
Water Reclamation Facility. I talked to Ms. Amy Gilliam
about my project, who directed me to Ms. Sonja Williams.
PURPOSE
My purpose is to find out which water is the healthiest concerning
the amount of mercury, arsenic, and lead in each.
MATERIALS
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125 mL of Zephyrhills Distilled Water
125 mL of Zephyrhills 100% Spring Water
125 mL of Zephyrhills Drinking Water
125 mL of Tap Water
125 mL of Glacier Purified Water
125 mL of Home Purified Water
18 Large plastic measuring vials
18 Small plastic measuring vials
1 µl of Nitric Acid
40 µl of Matrix Modifier
3.75 mL of Potassium Permanganate
2 mL of Potassium Persulfate
1 mL of Nitric Acid
2.5 mL of Sulfuric Acid
Assorted pipettes
METHOD > ARSENIC & LEAD
1. Pour 50 mL of each water sample into 6
different plastic measuring vials.
2. Add 0.5 microliters (µl) of Nitric Acid to each
vial.
3. Pour 2 mL of the vials into even smaller vials.
4. Add 20 microliters of Matrix Modifier to the
smaller vials.
5. Place the vials into STPGFAA—Graphite
Furnace Atomic Absorption and type the list of
samples to be tested.
6. After receiving results, document the amounts
displayed.
METHOD > MERCURY
1. Pour 25 mL of each water sample into 6 different
plastic measuring vials.
2. Add 1 mL of Nitric Acid to each vial.
3. Add 2.5 mL of Sulfuric Acid to each vial.
4. Add 3.75 mL of Potassium Permanganate to each
vial.
5. Add 2 mL of Potassium Persulfate to each vial.
6. Add 1.25 mL of Hydroxemene to each vial.
7. Place the water into the Manual Cold Vapor Atomic
Absorption machine; type the list of samples to be
tested; test the samples and document the results.
RESULTS > ARSENIC
Sample
Exp. 1
Exp. 2
Mean
Z. Distilled
-0.000246
-0.000217
-0.000231
Z. Drinking
-0.000561
-0.000284
-0.000423
Z. 100%
Spring
0.000364
0.000313
0.000339
Glacier
-0.000182
0.000133
-0.000024
Tap
-0.000256
-0.000032
-0.000144
Home Purified
-0.000626
-0.000443
-0.000534
Some of the results are negative because they are negligible.
RESULTS > LEAD
Sample
Exp. 1
Exp. 2
Mean
Z. Distilled
-0.000138
-0.000128
-0.000138
Z. Drinking
-0.000007
0.000043
0.000018
Z. 100% Spring
0.000077
-0.000165
-0.00044
Glacier
-0.000143
-0.000120
-0.000131
Tap
-0.000124
-0.000209
-0.000166
Home Purified
0.000210
0.000336
0.000273
RESULTS > MERCURY
Sample
Exp. 1
Exp. 2
Mean
Z. Distilled
0.000002
-0.000008
-0.000003
Z. Drinking
0.000000
0.000002
0.000001
Z. 100% Spring
-0.000001
0.000002
0.000000
Glacier
-0.000002
-0.000008
-0.000005
Tap
0.000003
-0.000002
0.000001
Home Purified
-0.000008
0.000009
0.000000
RESULTS > STANDARD
The EPA standards are…
Arsenic = 0.010 mg/L
Lead = 0.015 mg/L (action level)
Mercury (inorganic) = 0.002 mg/L
Compared to the standards, all of the waters are healthy concerning
metals.
DISCUSSION
I thought I would be comparing more dramatic results—for example, 1.7 to 3.6 instead of a
negative number to another negative number.
All of the waters are good. The scientist I worked with, Ms. Sonja Williams, said so herself.
There was an advertisement for a Pur® tap water filter that cost $39.99 and that claimed to
remove 99% of the lead in tap water. Not that there’s very much to remove. The mean
amount of lead in tap water was a negative number! Ms. Sonja Williams herself, who works
with data about metals in water, drinks tap water straight from the sink. It does claim to
remove microbial cysts, though. Microbiology is a whole different story.
DISCUSSION
Mistakes Made That Did Not Affect the Results
 One of the mistakes I made was not taking enough notes. If I had taken the time to take efficient
notes, then I wouldn’t have zapped some of the time of the scientists working at the laboratory.
Errors That Might Have Affected the Results
 Normally, according to the EPA’s methods, after chemicals are put in samples, the samples are left
to settle overnight before the actual test takes place. We did not do that for this science
experiment.
 Although I tried to pour the exact amount of water required for the samples (see slides 7-9) and
pipette out the majority of excess water, some of the amounts could have been slightly higher or
lower than the correct amount.
 When documenting the numbers off of the page of results, I could have looked at the wrong set of
numbers, but I am pretty sure that the numbers are all correct.
CONCLUSIONS
 The results were negligible. The waters I tested are all fine to drink.
 My hypothesis was incorrect. Glacier water was not the best kind of water. None
of the water types were the best.
Please keep in mind that just because your drinking water
does not have many metals in it does not mean that it is the best
kind of drinking water. To get a full picture of how healthy your
water is, you would need to run other tests on it such as tests for
microbes and pesticides.
TRIBUTE TO SCIENTISTS
This experience gave me a new respect for scientists. I want to
thank those people who are willing to wade through an ocean of
data to keep our water, our food, and our lives safe. The title of this
project is “What’s In Your Water?” But here is another question–
Who’s Behind Your Water? This tribute is for every scientist working
to keep my life from being endangered and working to improve it in
any way they can.
BIBLIOGRAPHY
 I would like to thank my parents.
 I am also grateful for the help of Ms. Sonja Williams, Staff Scientist at OCU South Water
Reclamation Facility.
 I am indebted to Ms. Kathleen Gauthier, another scientist at the SWRF.
 I would also like to thank Ms. Amy Gilliam, a PhD in Microbiology.
The following are websites that I used as extra sources:
http://www.brooklyn.cuny.edu/bc/ahp/LAD/C5/C5_Size.html
http://www.epa.gov/waterscience/methods/method/files/200_9.pdf
http://www.epa.gov/region9/qa/pdfs/245_1dqi.pdf
http://water.epa.gov/drink/contaminants/index.cfm
All three scientists worked at the OCU South Water Reclamation Facility.
Orange County Utilities
MY EXPERIENCE