Natural Science Seminar

Abstracts - Spring 2005

Abigail Miner
January 31, 2005
The effects of Stekoa Creek on the water quality of the Chattooga River

Mentor: Dr. Mark Brenner

Abstract: The Chattooga River is located on the border of northeast Georgia and northwest South Carolina.  It is a federally designated Wild and Scenic River and it is known for its stunning natural beauty, challenging whitewater and generally good water quality.  Stekoa Creek flows into the lower part of the Chattooga River and is a potential threat to the water quality of the Chattooga.   The objective of this study was to determine the effect of Stekoa Creek on the health of the Chattooga River by comparing the water quality upstream and downstream of the confluence of the two waterways.  Biochemical  oxygen demand (B.O.D.) , total suspended solids (T.S.S.), ammonia (NH3),  and fecal coliform tests were preformed. Samples were collected from three sites on five dates.  For fecal coliform, B.O.D. and T.S.S. testing, established methods were used as described in the Standard Methods for the Examination of Water and Wastewater.  For ammonia testing, the Hach-Nessler variation on the standard methods was used.  All results were analyzed with a repeated measures A.N.O.V.A.  No significant variation between sites was found for B.O.D, T.S.S. and NH3, with P values of 0.6883, 0.1579 and 0.7863 respectively.  For fecal coliforms, the variation between all three sites was found to be extremely significant with a P < 0.0001.  While  NH3, T.S.S. and B.O.D. all indicated generally good water quality, these data indicate that Stekoa Creek is detrimentally affecting the fecal coliform levels of the Chattooga river.  One probable source is primitive septic systems in the Stekoa Creek watershed, along with a leaky sewer infrastructure in the town of Clayton, Ga.
James Stultz
Factors Contributing to Ciguatera Toxicity in Bahamian Barracudas
January 31, 2005
Mentor Dr. Paul Bartels


     Ciguatera fish poisoning is the most common marine seafood toxin disease worldwide.  Ciguatera is a form of poison that is caused by the consumption of large carnivorous fish.  At least 50,000 to 500,000 people per year suffer from ciguatera poisoning, and cases are largely confined to tropical and subtropical areas.  Ciguatera poisoning comes from a toxin produced by the dinoflagellate Gambierdiscus toxicus.  In the Caribbean, fish toxicity appears to increase with the size of the fish.  Herbivorous reef fish introduce ciguatera into the food chain by ingesting the toxic dinoflagellates G. toxicus.  The toxins are then transferred to carnivorous fish where they are concentrated in the flesh and viscera.  The objective of this study was to determine if location, size, and the presence of external parasites could be used to accurately predict ciguatera toxicity in Bahamian barracudas.  The study was conducted in the Atlantic Ocean off the coast of Florida and throughout the Bahamas islands, and data was collected from the 22nd of May through the 4th of June.  During the sampling period, 22 samples were obtained and all samples were used in analysis.  Correlation analysis was used to detect any significant correlation between toxicity and the distance to shore, distance to reef, distance to shelf, water depth, length, and weight.  The p-value for each of the variables were as follows; toxicity vs. distance to shore 0.0780, toxicity vs. distance to reef 0.5706, toxicity vs. distance to shelf 0.2311, toxicity vs. water depth 0.2999, toxicity vs. length 0.1120, and toxicity vs. weight 0.0105.  A t-test was used to determine if there was any significant difference between toxicity and the presence of external parasites.  The p-value was 0.9326.  An ANOVA test was used to see if there was any significant difference between toxicity and the different island groups.  The p-value was 0.9862.  Of all the variables tested, weight was the only variable that had a p-value low enough to suggest that weight had a strong correlation to toxicity.  Most locals believe that the presence of external parasites could be used in predicting toxicity among barracudas.  My results do not support the hypothesis of using parasites to predict toxicity among barracudas.  The data also suggest no difference between toxicity and where each fish was caught. 


Erin K. McVey
February 7, 2005
Heavy Metals in American Alligator (Alligator mississippiensis) Eggshells from Three Florida Lakes

Mentor:  Dr. John Brock

Abstract:  For the past decade, scientists have turned to synthetic pesticides to explain the morphological abnormalities, altered hormone levels, and decreased egg viability rates of Florida’s American alligators (Alligator mississippiensis).  No studies have looked at the presence of metals in American alligator eggshells.  Heavy metals have an affinity for reproductive organs and overexposure can lead to toxicity.  Eggshells have been shown to provide another method for excreting metals from the body.
    Three eggs were collected from five different nests on Lake Woodruff, Lake Apopka, and Lake Griffin.  Approximately fifteen eggs were collected from each lake.   Lake Woodruff was used as the control lake in this study; Lake Griffin and Lake Apopka were not.  An Inductively Coupled Plasma Spectrometer (ICP) was used to measure the concentration of heavy metal ions in American alligator eggshells. 
    Detectable levels of six heavy metal ions were measured in American alligator eggshells.  The p-values obtained from a one-way ANOVA variance test determined that there was not a significant difference in the concentration of the metal ion, in the eggshells, between the three lakes.  The r2 values and p-values obtained from the correlation analysis showed no correlation between the metal concentrations in the eggshells and the egg viability rates specific to each lake.

      ANOVA one-way variance results    

Metal

Type of Test

p-value

Cd

non-parametric

0.5236

Cr

non-parametric

0.3619

Fe

parametric

0.1419

Mg

non-parametric

0.2777

Mn

parametric

0.9807

Ni

parametric

0.2048

    Correlation analysis results

Metal

r2

p-value

Cd

0.04821

0.8591

Cr

0.5418

0.4733

Fe

0.5404

0.4743

Mg

0.6475

0.4047

Mn

0.3853

0.9937

Ni

0.9875

0.0714*

   
These data do not support the hypothesis that heavy metals affect egg viability.
Maureen McKenna
February 14, 2005
Monitoring Beneficial Insectary Habitats on a Certified, Organic, Mixed-Vegetable Farm
Mentor: Dr. Laura Lengnick

Abstract: Organic farmers must find alternative methods of crop pest management because certification requirements prelude the use of chemical insecticides.  John Rowland, owner of ‘R’ Farm – a certified organic vegetable farm in Weaverville, NC, has been practicing a method of pest control called farmscaping.  Rowland plants beneficial insectary habitats of annual flowers or herbs in bed-row ends in order to encourage populations of beneficial insects that are predators or parasitoids of insect pests.  The objective of this study was to determine the success of the various insectary plants in attracting beneficial insects and not providing harborage for pest species.  The design of the plots mirrored that of Rowland’s as closely as possible.  Data were collected using an observational technique in which the frequency of visits to the flower by beneficial or pest arthropods was recorded.  Data analysis required that all the insects be identified and classified into functional groups as beneficial, pest, or unknown.  Bishop’s flower was found to have significantly more visits from beneficial insects than either calendula or buckwheat (p-value = 0.000 in both cases).  The literature supports the finding that bishop’s flower is a good insectary plant, but suggests that buckwheat should be an appropriate choice as well.  In further investigation, it was found that buckwheat was being observed at the wrong time of day in order to monitor beneficial insect activity.  Calendula was shown to have significantly more visits from pest insects than bishop’s flower (p-value = 0.013).  Calendula’s high pest visitation frequency resulted from a black blister beetle invasion during three dates in late August and was probably the result of a nearby farms alfalfa harvest.  Future study of Calendula and buckwheat are needed to determine their effectiveness as beneficial insectary plants.  Bishop’s flower was found to be a good plant to use in order to attract beneficial insects.


Laurel E. Key
February 14, 2005
Prescribed burning effects on the density and diversity of small vertebrates at Jones Mountain
Mentor: Dr. Louise Weber

Abstract: Prescribed burning is a mechanism used to prevent wildfires and control invasive species.  However, studies in other habitats have found that fire can alter species density and diversity.  My objective was to determine whether prescribed burning is having a detrimental effect on small vertebrates at Jones Mountain, Buncombe County, NC.  I conducted a 40 day mark-recapture study on burned and unburned areas using the Schnabel method for continuous mark-recapture.  Population density was estimated to be 31 small mammals on the burn side of the W.C. Davis Stand between Sept. 4 and Dec. 4, 2004.  On the unburned side, population density was estimated to be 58 small mammals.  No salamanders were caught.  The primary small mammal taxa were white-footed mice (Peromyscus leucopus), 52 of 53 total small mammals caught.  With more replication, my results would imply that small mammal population density in unburned areas on Jones Mountain is almost twice that of burned areas.  This suggests that small mammals, primarily white-footed mice, prefer unburned forest stands, making it vital to preserve this habitat and study small mammals closely following burns.
Irene Redmond
February 6, 2005
The Effects of Agriculture on the Water Quality and the Invertebrate Communities of Shope and Bull Creeks
Mentor: Dr. Mark Brenner

Abstract: Non point source (NPS) pollution from agriculture is a major cause of water pollution in the United States. Five sites in an agricultural watershed along Shope and Bull Creeks in Buncombe County, N. C. were sampled over four dates in the fall and winter of 2004. Samples were analyzed for total suspended solids (TSS), biochemical oxygen demand (BOD), and invertebrate sampling was done once at the furthest upstream and downstream sites to determine the effects of one farm on the water quality of Shope and Bull Creeks. The data were analyzed using a repeated measures ANOVA statistical test. The p-value for TSS was 0.5749 and the p-value for BOD was 0.6127. I cannot conclude that there is a significant difference in the concentration of these parameters between sites. The invertebrate composition included all the same taxa upstream and downstream except one invertebrate that was only found in the headwaters, Order Diptera, Family Tipulidae, the crane fly. The results suggest that there is no evidence to support the claim that this farm is polluting the water for the parameters I tested.


Ryan M. Tarbell
February 21, 2005
Instinctive Archery:  A Study of the Aiming Process
Mentor:  Dr. Mark Brenner

Abstract: The origin of archery is over 12,000 years old, and since that time every race and nation has used some form of the bow and arrow.  Barebow shooting is defined as shooting the bow and arrow without any external sighting device, but many forms of barebow shooting use reference points on the arrow, bow, or bow hand that aid in the aiming process.  Instinctive shooting is a form of barebow shooting that uses no conscious reference points.  It is widely debated if instinctive shooting uses subconscious reference points, and no studies have been conducted on the matter.  The objective of this study is to determine if archers claiming to be instinctive shooters actually use any type of reference point while shooting instinctively.  Six archers identifying themselves as instinctive shooters and three barebow shooters who stated they consciously use reference points shot ten arrows at a red laser dot from fifteen meters in normal lighted conditions and in complete darkness.  The distance of each arrow from the bulls eye was recorded for each test group.  The ten shots in each test group were used to run an unpaired Welch corrected t-test for each archer.  All archers had a p-value of less than 0.05 except one archer that used reference points with a p- value of 0.077.  The data strongly suggests that instinctive shooters are using subconscious reference points.  The shooters in this study may not truly be instinctive shooters, or instinctive shooters may use subconscious reference points.
 

David V. Tormey
February 28, 2005
Nitrogen release by alfalfa (Medicago sativa) and corn (Zea mays) crop residues 
Mentors: Dr. Mark Brenner and Dr. Laura Lengnick

Abstract:  Nitrogen is the most common limiting nutrient in crop production.  Both synthetic nitrogen fertilizers and fixation of nitrogen in root nodules of legumes can contribute to providing sufficient nitrogen to crop production.  Crop rotations that include a legume crop that fix sufficient nitrogen decrease the need for applied synthetic nitrogen fertilizers.  The purpose of this study was to determine the useable nitrogen levels in a Warren Wilson College Farm field soil after a rotation of two years of alfalfa and after a year of corn.  Soil samples were collected from the Big Bottom field in the spring after the alfalfa/legume mix had been tilled and in the fall after the corn had been tilled.  Three sample dates were collected 10-12 days apart after both crops were tilled.  The samples were analyzed for both NH4+ and NO3-  using methods found in the HACH spectrophotometer manual.  A repeated measures ANOVA was used to analyze the results.  There was a significant increase in NO3- over the three sample dates (P < 0.0001) after the alfalfa was tilled.  The NH4+ values after the alfalfa was tilled showed no significant difference.  Significant differences were found for both NH4+ (P < 0.0352) and NO3- (P < 0.0079) after the corn was tilled.  These results show a strong change in NO3-  after the alfalfa was tilled as well as a significant change in NO3-  after the corn was tilled.  These significant but different levels of increase are due to the warm and cold temperatures at the time of sampling and the high and low amounts of nitrogen in the two different crop residues.


Kristal Dawn McKelvey
February 28, 2005
Community Structure of Aquatic Tardigrades in Cades Cove – Great Smoky Mountains National Park
Mentors: Dr. Paul Bartels and Dr. Mark Brenner

Abstract: Tardigrades are a major component of the meiofaunal community and are believed to be important in trophic webs, yet little is known about their ecology, and this is especially true of freshwater tardigrades. The All Taxa Biodiversity Inventory (ATBI) is a biological initiative to identify every organism in the Great Smoky Mountains National Park (GSMNP) and tardigrades are being studied as part of this initiative. Abrams Creek in the Cades Cove area of the GSMNP is of particular interest because it has not been surveyed for tardigrades and it has underlying limestone geology, which is rare in the Appalachian Mountains.  Limestone aquatic systems are generally high in biological productivity due to high alkalinity and water hardness. The objective of this study was to identify the aquatic tardigrade species present in Abrams Creek to add to the ATBI, and to evaluate the diversity and similarity of tardigrade communities in three sites of the unique Cades Cove watershed.  Four periphyton and four sediment samples were collected at each of three sites:  upstream of the limestone area, a limestone spring, and immediately downstream of the limestone area. These samples were preserved, concentrated, and then examined for tardigrades using a dissecting microscope.  Each tardigrade was mounted on a slide and identified to the species level using phase contrast microscopy.  A total of 306 specimens were identified.  Twenty-five different tardigrade species were found, seven of which were new to the ATBI collection.  The aquatic section of the ATBI database now has 31 total aquatic species.  The statistical program EstimateS 7.0 was used to calculate similarity and diversity. Tardigrades in sediment were very patchy ranging from only 2-5 species, while periphyton tardigrades were diverse ranging from 12-18 species.  The Abundance-Based Coverage Estimator in EstimateS 7.0 estimated total species levels to be 17 ± 1.07 upstream, 19.02  ± 1.31 in the spring, and 22.72  ± 5.75 downstream for periphyton samples.  The Bray-Curtis similarity index was calculated between the different sites with the downstream site and the upstream site having the lowest similarity at 0.341 and the limestone sites, spring and downstream having the highest similarity at 0.5.  Seven of the 25 species found were new records for the Smokies.  Five may be new to science, and three are new to North America.  A second set of samples was collected in December 2004 and it will be evaluated this semester to further delineate the ecological uniqueness of the Abrams Creek watershed.  My data suggests that there are unique tardigrade species in the Cades Cove area and there may be increased diversity with increased limestone exposure.
Rebecca Rudicell
March 7, 2005
The environmental fate of dibutyl phthalate in a freshwater system with zebrafish (Danio rerio) embryos
Mentor: Dr. John Brock

Abstract: Dibutyl phthalate (DBP) is a known developmental toxin and an endocrine active compound.  Researchers at Warren Wilson College have previously examined DBP exposure and zebrafish (Danio rerio): Ferguson (2002) determined DBP to be toxic to zebrafish embryos; Stokes (2002) determined the LD50 for zebrafish embryos to be 2.4 ppm; and Lucas (2004) determined the LD50 to be 53 ppm.  These studies did not examine the distribution of DBP within the experimental system.  How much DBP actually partitions into the eggs?  The objective of this study was to determine the environmental distribution of DBP is a mock-freshwater system with zebrafish eggs and to determine the partitioning coefficient between the eggs and water.  Zebrafish eggs were collected daily and exposed to one of four treatments: 1.54 ppm DBP, 3.37 ppm DBP, 4.67 ppm DBP, and a methanol control.  Another treatment set was performed in the same manner, without eggs.  Samples were analyzed using solid phase extraction (SPE) and gas chromatography with flame ionization detection (GC-FID).  Dimethyl phthalate (DMP) was used as an internal standard.  Each day’s data were calibrated with a known standard and adjusted for percent recovery from the SPE.  The only statistically significant difference of note between treatments groups was between 1.54 ppm with eggs and 1.54 ppm without eggs (P<0.01).  On average, 36.92 ± 17.42 % of the DBP was either absorbed or metabolized by the eggs, 55.53 ± 16.07 % of DBP remained in the water as the parent compound, and 7.55 ± 15.69 % of DBP was lost to other sources.  Correcting for the number of eggs in each sample did not decrease the high variability of the data.  In this study, Kegg was determined to be 113 ± 70.  DBP partitioned into the eggs at concentrations 113 times greater then the concentration of DBP in the surrounding water.  Log(Kegg) was determined to be 2.06 ± 0.27.  Log(Kegg) was much lower than the reported values of  log(Kiso), 3.7, 4.45, and 4.72.  DBP partitioned into the eggs 100+ times less then it would partition into isooctane, possibly suggesting the presence of water within the egg or a barrier that limits DBP absorption by the egg.  
Patty Baxter
March 7, 2005
Little Brown Bat habitat and inhabitation of bat boxes on Warren Wilson Campus
Mentor: Dr. Lou Weber

Abstract: There is a population of Little Brown Bats (Myotis lucifugus) on the Warren Wilson College Campus, and very little is known about this population. A way to be able to study and learn more about this population is to have them in a place where you can observe them, and this can be done by putting up bat boxes. This study is what will start introducing Little Brown Bats to campus in places where they are easily accessible to students and the general public. The objective of this study was to define the distribution of and define the habitats of Little Brown Bats on the Warren Wilson College Campus. The methods used in this study were observation of the population of bats in the bat houses, and the Weber Qualitative Habitat Assessment for forest. Overall no bats inhabited the bat houses on the dates that were observed. The Warren Wilson College Campus has all the aspects to support a population of Little Brown Bats. The college has some roosting sites, as well as some good foraging sites for them. The college has aspects such as still water sources, patchy forests, older stands, and a mixed forest matrix. The college could be a place to educate the public about what a bat actually does, and how helpful they are.


Saba Alemayehu
March 28, 2005
The Effect of pH on the survival of the aquatic Tardigrade Hypsibius dujardini
Mentors: Dr. Paul Bartels and Dr. John Brock

Abstract: Tardigrades are a major component of the meiofaunal community, yet little is known about their habitat requirements or ecological tolerances, particularly regarding pH. Acidification of streams, due to acid rain, has been shown to lead to elimination of some aquatic organisms, which in turn can lead to a loss of biodiversity. Distribution patterns of some tardigrade species are known to be affected by pH. The Great Smoky Mountains National Park (GSMNP) has been shown to be one of the most polluted National Parks in the Untied States, due to a heavy effect of air pollution. In turn, the streams in the GSMNP have also been affected by the increase of acid rain. Hypsibius dujardini is a common species found in the GSMNP.  A direct study of the effect of pH on the survival of tardigrades has not been published. The first objective of this study was to determine the effect of pH on the survival of the aquatic tardigrade Hypsibius dujardini using a broad pH range from pH 7-2 and then using a more specific pH range from pH 3-2. The second objective of this study was to examine the effects by long term exposure to pH 4 and pH 3 on the aquatic tardigrade Hypsibius dujardini. Hypsibius dujardini was cultured in small dishes containing algae as food source.  In the first experiment these tardigrades were run through a short term (5 minute) protocol using a pH range from 7-2, then again using a pH range from 3-2.  Another experiment was performed by exposing Hypsibius dujardini to a long term (30 hour) treatment of pH 4 and pH 3.  The results in the first experiment showed that there was a significant difference in activity at pH 3 and no tardigrades survived at pH 2.8. The results of the second experiment showed that there was a significant drop in activity after 10 minutes at pH 3 and also after 1 hour at pH 4; at pH 3 all specimens became inactive after 20 minutes. These results demonstrate that the activity of tardigrades can be affected by short term exposure at pH 3 and by long term exposure at pH 4. The lowest pH recorded in the GSMNP is 4.2 and this is very near the level that I’ve shown to be detrimental.
Valerie Bartell
April 4, 2005
Kombucha tea and the risk of pathogenic contaminants in home-brew cultures
Mentor: Dr. Jeffery Holmes

Abstract: Kombucha tea is an ancient home remedy originating in Asia that is produced by the fermentation of sugared black tea with a symbiotic culture of yeast and bacteria. In general, the bacteria belong to the genus Acetobacter, but the species of yeast are more variable. The tea has been claimed to have many therapeutic affects, but the FDA cautions that home-brewed cultures grown in non-sterile conditions could contain pathogenic contaminants. The objective of this study was to assess the risk of contamination with such potential pathogens as Escherichia coli and Candida albicans in Kombucha tea. Kombucha cultures were prepared with black tea (0.35% w/v) and cane sugar (6.8% w/v) using a commercial starter culture and 10% by volume of previously fermented tea. Samples of the Kombucha tea were taken between fermentation days 1-14 and used in an agar diffusion assay with E. coli and C. albicans. The antimicrobial activity of Kombucha tea against E. coli increased with fermentation time, while no inhibition was observed for C. albicans. A second assay measured the survival of E. coli and C. albicans (separately) in the fermenting tea. Both microorganisms were seen to grow in plain sugared black tea and decline in population when added to K-tea. The concentration of E. coli declined rapidly to zero between 6 and 48 hrs. The concentration of C. albicans declined more gradually and reached zero on the 9th day of fermentation. The rate of inhibition varied between cultures, but in each the degree of inhibition increased with fermentation time. Increased inhibition is partly due to a decrease in pH but also possibly to an increase in metabolites from the black tea. It can be concluded that with these Kombucha tea cultures the risk of contamination with E. coli and C. albicans is relatively low and decreases with increased fermentation.  However, there is still a potential risk of contamination with other pathogenic organisms not focused on in this study.

Tom Hughes
April 11, 2005
Potential for biogas production from two exotic, invasive plant species, Kudzu (Pueraria montana) and Japanese Honeysuckle (Lonicera japonica)
Mentor: Dr. Mark Brenner

Abstract: Anaerobic digestion is a process during which a consortium of bacterial species degrade organic material in the absence of oxygen, producing as a product a mixture of methane and carbon dioxide known as biogas. Due to the similarities between biogas and fossil-derived natural gas, recent research has focused on optimizing the anaerobic digestion process for the conversion of plant feedstocks to biogas for use as an alternative fuel. Plant species from over 100 genera have been evaluated as feedstocks for biogas production. The objective of this study was to evaluate two species of exotic invasive plants common in the southeastern United States, Kudzu and Japanese Honeysuckle, as feedstocks for biogas production. A biochemical methane potential (BMP) assay was used. Feedstock samples were combined with a defined media and bacterial inoculum and incubated until gas production ceased. Mean ultimate gas yields (liters of gas per gram volatile solids added) after 60 days of digestion were 0.39, 0.32 and 0.49  for Kudzu, Japanese Honeysuckle and a cellulose positive control, respectively. A non-parametric ANOVA was used to compare these yields. There was no significant difference between treatments (p=0.1679) suggesting that both species have a potential biogas yield similar to that of pure cellulose. While the invasive characteristics of these species preclude their use as cultivated energy crops, their relatively high biodegradabilities as well as the fact that current management strategies involve removal may make them ideal feedstocks for biogas production.

Jesse E. Downs
April 18, 2005
The effect of a pasture supplemented diet on lipid oxidation in pork
Mentor: Dr. Victoria Collins

Abstract: This study investigated the effect of a pasture supplemented diet on lipid oxidative stability in pork.  This is a standard test of meat quality.  Two groups of hogs were raised – one group was farrowed indoors and raised outside on a bare soil lot (pasture - ).  The other group was farrowed outdoors on pasture and remained on pasture until time of slaughter (pasture +).  The pigs were fed the same diet, ad libitum, consisting of corn, soybean meal (SBM) and a vitamin-mineral supplement.  Hogs were slaughtered at approximately six and a half months of age and an average live weight of approximately 130 kg.  Ground pork (2:1 meat/fat) from 18 hogs in each group was analyzed for the lipid oxidation product malondialdehyde (MDA) using the thiobarbituric acid reactive substances (TBARS) test after 1, 3, 8, and 16 days of refrigerated storage.  The product of this reaction was quantified using spectrophotometry at 534.15 nm.  Mean MDA concentrations for each group on each day were compared using an unpaired t-test assuming unequal variance.  The meat from the pasture (+) group was found to have higher initial oxidation (days 1 and 3), but at days 8 and 16 the pasture (–) group tended to have higher oxidation.  The oxidation of the pasture (+) pork was eclipsed by that of the pasture (-) pork at approximately 6 days of storage. 
Charlotte Litjens
Hydrolytic degradation of polycarbonate beverage containers and migration of bisphenol A into liquids
Mentor Dr. Dean C. Kahl
April 25, 2005
             
Abstract: Bisphenol A (BPA) is a monomer involved in the formation of polycarbonate plastics, and has been documented as an endocrine active compound in several reports in the literature. Migration of bisphenol A from polycarbonate beverage containers due to hydrolysis of polymers has also been shown in the literature. The objectives of this research were to develop a method to measure bisphenol A, in order to determine the degree to which bisphenol A migrates from polycarbonate water bottles. Cut portions from Nalgene® brand polycarbonate water bottles were exposed to hot water, cold water, hot isooctane, and cold isooctane. Isooctane was chosen to simulate fatty liquids based on reports in literature showing the same migration results for monomers of other plastics into isooctane and fatty foods. An internal standard was used for quantitation. Test liquids were analyzed for the presence of BPA having migrated from polycarbonate using gas chromatography/mass spectroscopy in the Selective Ion Monitoring (SIM) mode. In the first experiment, no detectable BPA was present in water or isooctane at a concentration higher than 9 ppm. In a second experiment, out of twenty samples, four had bisphenol A present. A water blank treated in the oven had a concentration of 40 ppb BPA, suggesting contamination. The same samples were analyzed using GC/MS again, showing no detectable BPA. The model of exposure used in this experiment was a 3- fold exaggeration of normal bottle use according to surface area to volume ratios. The results of this study differ from published results regarding baby bottles and prepared PC samples, suggesting that Nalgene® water bottles may be safer for drinking. Long-term research should be conducted to test extended use and aging of this type of polycarbonate.