Body Bacteria

This Progress Report submitted by Joshua Catone, Rob Magorien, Mike Bade, Kendal Robinson [e-mail:Robinskb@muohio.edu] on 11/23/02.

Joshua Catone, Rob Magorien,
Mike Bade, Kendal Robinson
NS Student Generated Lab
11.23.2002

BODY BACTERIA
INTRODUCTION:
Science has always been concerned with the differences between the sexes. We decided for our student-generated lab that we will compare the bacteria content of males to females. We decided on this lab after several other ideas that didnÕt pan out. We thought early on that we would like to a behavioral study, but we also know that surveying people is not a reliable source of data. Finally, we came to the conclusion to meld behavioral and biological science. Does the male body make a more viable home to bacteria than women? This is the core of our study and we hypothesize that there will be no difference between the bacterial content of our male and female subjects.
We plan to understand the small differences of gender, specifically the natural cleanliness of each. It will be an interesting insight to the marvels of human beings. By accomplishing our tasks, we will have a new understanding of the symbiotic relationship between humans and bacteria.
This research is relevant to everyone. Through our tests we can learn about human hygiene and its importance. Being college students, we live in a world infested by germs, and proper hygiene can be the key to fending off illnesses. Everyone can benefit from knowing the details of such a subject.
Our research will hopefully help everyone to engage the world around them and be aware of the unseen life that exists in and around us. Through these procedures, the class will know which sex is more susceptible to illness, if one is more than the other, through extrapolation of our findings.
Body odor can take on several different meanings; whether it means body odor in the sense that it arises from the underarm and groin area, foot odor, and bad breath. The typical body odor normally comes from sweating. Sweat, emitted from the eccrine gland is the bodyÕs way of cooling off. As the bacteria emitted decomposes on the body, odor is released causing what is known as Òbody odorÓ. Bathing or showering every day using a mild soap and warm water aids in the removal of odor causing bacteria (TeensHealth 2002).
There are ways in order to eliminate body odor. Typically, deodorant is used to aid in this process. In an experiment done at the Bacteriological Institute of Heidberg Hospital in Hamburg, researchers tested the effects of farnesol, an inhiitor of gram-positive bacteria which produce body odor. These researchers determined that with a farnesol concentration of 0.3%, it was capable of breaking down body odor causing bacteria. Later, researchers at the Hill Top Research, Inc. tested the effectiveness of farnesol compared with that of triclosan. Here, 20 males and 20 females were both given sticks of the two chemicals, and were observed over a short period of time. It was determined that there was no significant difference between the two chemicals after 12 and 24 hour periods. (Dragoco)
Bad breath can also be attributed to body odor. Bad breath may be caused by bacteria in the mouth, stomach and intestinal disturbances, and bowel sluggishness. Some foods also aid in causing bad breath. Some of these foods include garlic and onions. Deficiencies in vitamins A and B, and also zinc are a factor in the cause of bad breath as well. (Health 911)
There are several remedies to rid the mouth of bad breath. To start, one should practice good oral hygiene, carefully cleaning the three parts of the mouth: the tongue, teeth, and gums. Brushing the gums and tongue with cloves or myrrh aids in the removal of bacteria. Mouthwash is only a temporary remedy, and gargling extends its effectiveness. (Health 911)
Foot odor also plays a large part in the large body odor scheme. Foot odor is caused by sweaty feet and rapidly growing bacteria. Foot odor can be lessened by wearing cotton socks which absorb the sweat and allow the feet to ÒbreatheÓ.
The hands of a person are home to a large congregation of bacteria, some from our own body and some picked up from things we have touched. Millions of tiny microbes are carried on our hands (Cleanliness and Hygiene 2001). To rid our hands of these bacteria and thus aid in ridding ourselves of potential infection, it is emphasized that we must wash our hands before performing certain tasks and after certain tasks. Some of these include after using the bathroom, after touching garbage, before eating, and before attending an open cut (Cleanliness and Hygiene 2001).
Hair, part of our own experiment, is also a place where hygiene is necessary. Hair not properly cared for and treated can become oily and greasy (the oils are a product of the sebaceous gland which every strand of hair has (TeensHealth 2002). In order to prevent oily hair, it is recommended that one wash their hair every day with warm water and avoid using hair gels and lotions that add to the grease and oil. (TeensHealth 2002)

MATERIALS:
1 male subject for test 1
1 female subject for test 1
A group of male volunteers for test 2
A group of female volunteers for test 2
Cotton Swabs
Petri Dishes
Human Samples

METHODS:
Our study will focus on the bacteria concentrated in areas which we have explained in the latter part of this research. We will test areas around the body such as the hands, hair, eyelashes, fingernails, feet, mouth (tongue, lips, breath), and underarms and will compare our results between males and females. Though somewhat unpleasant, from data received we hope to determine which gender is the cleanest.

TEST 1- Individual testing
1. Select main male and female subjects.
2. Quantify and record Petri dishes.
3. Rub cotton swab on the following areas of each subject:
-Hair
-Underarms
-Palms
-Feet
-Tongue
-Lips
-Eyelashes
-Gums
-Fingernails
-Breath
4. Place cotton swab on Petri dishes
5. Seal and label Petri Dish with accordance to each subject and corresponding area
6. Let sit for approximately one week.
7. Observe Petri dish after sitting period. Count and record number of colonies on each.
8. View each dish under microscope and attempt to identify certain bacteria or fungal growths through taxonomical references.

TEST 2- Group testing
1. Locate group of male and female volunteers.
2. Observe Petri dishes in accordance with sex of volunteer. Count and record number of colonies on each.
3. Swab hands of volunteers.
4. Follow steps 4 through 8 of test 1

Note: The statistical soundness of the experiment has been ensured by the use of data tables to represent the data as a set of organized experiments designed to justify either the acceptance or rejection of a null hypothesis Ð hygiene differences between males and females is negligible. Our group will satisfy this by formulating a t-test based on the varying abundance of the agar cultures found within the Petri dishes. These quantifications will then be taken from the data tables and tested against the hypothesis that both agar cultures yielded the same distribution of growth weights (equal growths equal similar hygiene between male and females which is our null hypothesis). The test that will be most effective at verifying our hypothesis is the two-sample t-test test because our group will be dealing with data from two samples of populations (male and female) and the t-test will be able to measure the variability with the means of agar abundance and determine Ð based on the p value Ð the significance of the difference between samples.

RESULTS:
Body Parts

Body Part --
X 1 (Test 1- Boys) --
X 2 (Test 1- Girls)

Palms
322
398

Foot
275
368

Lips
225
468

Tongue
281
402

Underarm
306
420

Hair
283
170

Eye Lashes
403
462

Gums
472
410

Nails
412
473

Breath
371
350
Total: 335 392.1
T = -1.54
μ1 ≠ μ2
Sx1 = 76.7
Sx2 = 88.2
P = .14 which is >.05 so we fail to reject the null hypothesis that the germ count for subject A (male) is equal to subject B (female). We also fail to reject the null hypothesis that subject A is either more or less clean than subject B
P for μ1<μ2 = .07
P for μ1>μ2 = .93

Palms
--
X 3 (Test 2- Boys) --
X 4 (Test 2- Girls)

221
293

294
259

276
103

256
250

312
660
Total: 271.8 313
T= -.438
Sx3= 35.2
Sx4= 207.24
P= .683 therefore we fail to reject null that μ3= μ4 (germ counts in male and females are inherently equalÉor are they?)
P for μ3<μ4 =.341
P for μ3>μ4 = .659

DISCUSSION & CONCLUSION
Upon inspection of the aged Petri dishes through microscopes, we discovered two identifiable microorganisms. One is staphylococcus, which is the most common skin bacteria. Often referred to simply as "staph," is a bacteria commonly found on the skin and in the nose of healthy people. Therefore, it would not be uncommon to find these bacteria again if the experiment were repeated under the same conditions. Occasionally, staphylococci can get into the body and cause an infection. This infection can be minor (such as pimples) or serious and sometimes fatal (such as blood infections or pneumonia). The second organism found were aspergillus/pennicilus spores, a mold that thrives in moist conditions.
In conclusion, we failed to reject the original hypothesis that there would be no difference between the bacterial content of males versus females. Our results did not provide distinct information to conclude that one gender was in fact ÒdirtierÓ, or more infested by bacteria, than the other. From the observation and interpretation of our results, we concluded that there was enough information to fail to reject our hypothesis, and therefore retain our prediction that there is no difference in bacterial content between genders.
Because of the statistics, specifically the p-values of both tests, we conclude that more samples would be the key to improving this study. Since the p values in the tests of μx1<μx2 both show a near statistically significant trend toward a lower p value than the other tests, we feel that more tests would yield a different conclusion about gender and bacteria count. One of the testÕs P value was only slightly above the alpha level of .05 (5%), which signifies, at least for subject A, that there could actually be statistically less bacteria on him versus subject B if more tests were carried out.
In order to derive a more clearly defined conclusion, we would need to test more body parts as well as more people. Those samples would provide us with much more information to interpret to either reject or fail to reject our hypothesis. More samples would yield a greater n value and therefore higher degrees of freedom. When divided into the t equation, we would receive a higher absolute t value and therefore a more significant p value. This in turn would produce a lower p value, if in fact there is no difference in the bacterial content between males and females.

Cleanliness and Hygiene. 24 September 2002. _Guide/hygiene.htm>
Dragoco. 24 September 2002. 3.jsp>
Health 911. 24 September 2002.
TeensHealth. ÒBasic Hygiene.Ó 24 September 2002. _body/take_care/hygiene_basics.html>

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