<%BANNER%>

Record for a UF thesis. Title & abstract won't display until thesis is accessible after 2012-08-31.

Permanent Link: http://ufdc.ufl.edu/UFE0041998/00001

Material Information

Title: Record for a UF thesis. Title & abstract won't display until thesis is accessible after 2012-08-31.
Physical Description: Book
Language: english
Creator: Nocito, Brian
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2010

Subjects

Subjects / Keywords: Chemistry -- Dissertations, Academic -- UF
Genre: Chemistry thesis, M.S.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Statement of Responsibility: by Brian Nocito.
Thesis: Thesis (M.S.)--University of Florida, 2010.
Local: Adviser: Young, Vaneica Y.
Electronic Access: INACCESSIBLE UNTIL 2012-08-31

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2010
System ID: UFE0041998:00001

Permanent Link: http://ufdc.ufl.edu/UFE0041998/00001

Material Information

Title: Record for a UF thesis. Title & abstract won't display until thesis is accessible after 2012-08-31.
Physical Description: Book
Language: english
Creator: Nocito, Brian
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2010

Subjects

Subjects / Keywords: Chemistry -- Dissertations, Academic -- UF
Genre: Chemistry thesis, M.S.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Statement of Responsibility: by Brian Nocito.
Thesis: Thesis (M.S.)--University of Florida, 2010.
Local: Adviser: Young, Vaneica Y.
Electronic Access: INACCESSIBLE UNTIL 2012-08-31

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2010
System ID: UFE0041998:00001


This item has the following downloads:


Full Text

PAGE 1

1 INDUCTIVELY COUPLED PLASMA OPTICAL EMISSION SPECTROSCOPY (ICP OES) ENVIRONMENTAL ANALYSIS OF METALS FOLLOWING A SPACE SHUTTLE LAUNCH AT THE KENNEDY SPACE CENTER (KSC) AND FIREWORKS IN THE INSTRUMENTAL ANALYSIS TEACHING LABORATORY By BRIAN NOCITO A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE UNIVERSITY OF FLORIDA 2010

PAGE 2

2 2010 Brian Nocito

PAGE 3

3 To my family

PAGE 4

4 TABLE OF CONTENTS page LIST OF TABLES ............................................................................................................ 5 LIST OF FIGURES .......................................................................................................... 6 ABSTRACT ..................................................................................................................... 7 CHAPTER 1 ENVIRONMENTAL ANALYSIS OF METALS AT THE KENNEDY SPACE CENTER ................................................................................................................... 9 Introduction ............................................................................................................... 9 Experimental Section .............................................................................................. 11 Results and Discussion ........................................................................................... 14 2 AN EXPERIMENT FOR THE INSTUMENTAL ANALYSIS LAB ............................. 34 Introduction ............................................................................................................. 34 Experimental Backgro und ....................................................................................... 34 Procedure ............................................................................................................... 41 Sample Data Analysis Exercises ............................................................................ 46 Material Setup Sheet .............................................................................................. 48 3 CONCLUSIONS ..................................................................................................... 59 Summary ................................................................................................................ 59 Future Work ............................................................................................................ 59 Reference Acknowledgments ................................................................................. 60 LIST OF REFERENCES ............................................................................................... 61 BIOGRAPHICAL SKETCH ............................................................................................ 66

PAGE 5

5 LIST OF TABLES Table page 1 1 Calibration results of metals detected in environmental samples ....................... 22 1 2 Environmental conditions of samples collected at the KSC sites ........................ 23 1 3 Correlation matrix for baseline surface water data ............................................. 24 1 4 Correlation matrix for baseline sediment data .................................................... 25 2 1 Pre and post launch NASA soil data ................................................................. 49 2 2 Pre and post launch NASA water samples ....................................................... 50 2 3 Calibration plot data set ...................................................................................... 51 2 4 LLS fit results for calibration plots ....................................................................... 52 2 5 Concentrations of elements determined by external calibration ......................... 53 2 6 NASA Environmental Monitoring Memorandum ................................................. 54

PAGE 6

6 LIST OF FIGURES Figure page 1 1 A map of the sampling sites 1 14 located in the environment s urrounding Kennedy Space Center ...................................................................................... 26 1 2 Baseline concentrations i n mg L1 of the four most abundant metals detected in surface and muck water samples at sam pling sites 1 14 ............................... 27 1 3 Baseline concentrations in mg L1 of the other four abundant metals detected in surface and muck water s amples at sampling sites 1 14 ............................. 28 1 4 Baseline concentrations in mg L1 of the four trace metals detected in surface and muck water s amples at sampling sites 1 14 ............................................... 29 1 5 Surface water samples were collected at site L several weeks prior to and fifteen hours after the launch of the space shuttl e Endeavor STS 127 ............... 30 1 6 Topsoil samples were collected at site L several weeks prior to and fifteen hours after the launch of the space shuttle En deavor STS 127 ......................... 31 1 7 Su rface water baseline dendrogram ................................................................... 32 1 8 Sediment baseline dendrogram .......................................................................... 33 2 1 Parts 1 a and 1b illustrate the orientation and approximate distance of the moss bag, dish of water, and extingui shed sparkler .......................................... 55 2 2 Highlighted lo cation at Kennedy Space Center is behind launch pad 39A ......... 56 2 3 LDR strontium calibration plots for six student groups. ....................................... 57 2 4 Sparkler metal compositions as determined from ICP measurements on water samples. ................................................................................................... 58

PAGE 7

7 Abstract of Thesis Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Science INDUCTIVELY COUPLED PLASMA OPTICAL EMISSION SPECTROSCOPY (ICP OES) ENVIRONMENTAL ANALYSIS OF METALS FOLLOWING A SPACE SHUTTLE LAUNCH AT THE KENNEDY SPACE CENTER (KSC) By Brian Nocito August 2010 Chair: Vaneica Young Major : Chemistry Metals serve numerous functions within the body. They function as electrolytes, as a building block of hemoglobin for oxygen transport within the blood, as a component for follicle stimulating hormones and as inorganic cofactors for some enzymes. However, ingestion of absorption of certain specif ic metals, as well as overwhelming exposure to essential metals, can be harmful when absorbed and lead to health complications and conditions. While metals can be found to deposit in large quantities from environmental sources, the effect of anthropogenic activities can result in metal pollution in surrounding areas. In order to study the impact of anthropogenic actions Environmental indicators, such as moss, water, and soil, combined with metal detecting instrumentation may be used to measure concentrati ons of metals present in the biosphere. In order to monitor the environmental impact of rocket combustion, samples collected at the Kennedy Space Center have been analyzed for metals using inductively coupled plasmaoptical emission spectroscopy (ICP OES) The results are presented in Chapter 1.

PAGE 8

8 A two part teaching lab experiment enlightens students with the use of environmental indicators and ICP OES to monitor anthropogenic activities that may result in metal pollution in environmental samples. In part one, an experiment is designed to simulate the metal pollutants that originate from sparklers (small scale fireworks). Two environmental indicators, surface water and Spanish moss (Tillandsia usneoides), are exposed to a lit sparkler in a closed container The Spanish moss is subsequently microwave digested, and both samples are analyzed for 16 elements by ICP AES. In part two, the metal content of real samples taken from the environment (topsoil and surface water) surrounding the KSC launch pads before and after a shuttle launch are analyzed. Students learn several fundamental concepts including: atomic spectroscopy, biomonitoring, microwave digestion, matrix interferences, matrix matching, detection limits and the standard additions method. This experim ent is described in C hapter 2.

PAGE 9

9 CHAPTER 1 ENVIRONMENTAL ANALYS IS OF METALS AT THE KENNEDY SPACE CENTER Introduction Though several metals have been deemed essential for biological purposes, there is increasing evidence that inappropriate exposure to specific metals can be detrimental to the environment and human health [14]. In general, the occurrence of metals in the environment originates from several natural sources, including contributions from seawater [5, 6], geological deposits [7], and other elemental cycles [8, 9]. Despite the ubiquitous nature of metals, a heightened awareness has emerged toward assessing the widespread deposition and accumulation of metals in the biosphere as a result of anthropogenic activity [911]. To further improve the total assessment of anthropogenic pollution in both local and global environments, new studies focused on expanding the types of anthropogenic practices monitored need to be implemented. In parallel with the worldwide surge in industrialization, the resultant growth in production and consumption of metal products has led to new issues involving a consequential increase in metal byproduct and waste disposal. A wellreported anthropogenic activity shown to disperse considerable metal pollution into adjacent environments occurs as a result of fuel emission and automotive degradation [12, 13]. Reports have also shown a substantial influx of metal contamination into the environment in close proximity to urban effluents [14], consumption waste (e.g. ewaste, [15, 16]) and metal industry operations [1720]. Despite the numerous reports examining the principle sources of metal pollution in the environment, few reports have fully characterized the metal waste derived from atypical and lesser studied anthropogenic activities.

PAGE 10

10 One activity that has recently garnered considerable attention is the release if components from firework displays. Firework displays have been shown to disperse significant amounts of metal waste into the surrounding environment (ten to thousandfold increases in ambient levels) [2124]. In addition to metal waste, firework displays have also been shown to produce dramatic increases in harmful g ases and inhalable particulate matter [25, 26]. To provide specific combustive and coloring properties, specific metals (such as Al, Ba, Ca, Fe, and Mg) are added to fireworks in varying amounts [24, 27]. Similarly, the chemical properties (e.g. combustibi lity, durability, machinability) of several metals have been exploited by the aerospace industry in several aerospacerelated activities [28]. Alloys, made from both common and rareearth metals, have been heavily used in the engineering of spacecraft engi nes, semiconductors, and other specialized aerospacecomponents [4, 28, 29]. In addition, metals (such as Al) have been used as integral components of solid rocket fuel [30]. Thus, although ephemeral in nature, aerospacerelated activities possess the pote ntial of contributing metal waste into the environment. Since 1960, the Kennedy Space Center (KSC), located at Cape Canaveral, Florida, has been a principal site for aerospacerelated activities (including space shuttle launches) [31, 32]. Due to its immediate proximity to the environment located near and within the Merritt Island National Wildlife Refuge, there is both a high probability of metal deposition into the environment and a need to monitor this anthropogenic contribution. In this study, the basel ine metal content in both surface water and sediment samples was determined using inductively coupled plasma optical emission spectroscopy (ICP OES). The baseline analysis was performed by analyzing

PAGE 11

11 the environmental samples collected from several import ant sampling sites in the environment surrounding KSC, including sites near shuttle launch pad 39A, the vehicle assembly building (VAB), and the shuttle landing strip. In addition to obtaining background metal concentrations, metal content in both preand post launch surface water and topsoil samples (collected near launch pad 39A) were also determined. Likewise, a pair wise relationship was investigated to show a relation between salinity, distance, and metal concentration. Cluster analysis was also used to classify the results observed for the preand post launch results. Experimental Section The method was developed using a 48element High Purity Standards tuning solution (10 mg mL1, Charleston, SC) in 2% nitric acid. An external calibration curve wa s created by diluting the tuning solution to final concentration values of 0.01, 0.05, 0.1, 0.2, 0.5, 1.0, 2.0 and 10 mg mL1. For the three metals which were detected in the environmental samples above the standard calibration curve (Ca, Mg, and Na), additional standards of 25, 100, and 200 mg mL1 (from stock quantities of chlorinated salts) were added to extend the linear dynamic range. A matrix matched blank was prepared by adding concentrated nitric acid to milliQ water to a final concentration of 2% (12M, Fisher Scientific, Fair Lawn, NJ). The calibration standards were analyzed three times (each in triplicate) at each target wavelength. The target wavelengths chosen (Table 1) for each element were based on a combination of factors, specifically thos e previously employed in a method developed by the Environmental Protection Agency [33] and those primary or secondary emission lines which minimized potential spectral interferences in our preliminary experiments. The intensities at each wavelength were r ecorded (after blank correction)

PAGE 12

12 using a Varian Vista ICP AES instrument. The ICP was equipped with a quartz torch using argon as the source of the plasma. A charge coupled device was used for detection of the emitted light. The Vista software was confi gured to employ simultaneous variable equation analysis to determine the elemental concentrations while minimizing the interferences from other elements. The corrected intensities, combined with statistical regression, were used to establish the linear dynamic range (LDR) for each element. In several cases, the concentrations of Ca, K, Mg, and Na in the environmental samples were estimated by extrapolating beyond the calibration curve. The linear range, relative standard deviation (RSD), limit of detection matched blank) and limit of quantification 1). The ICP AES instrument was configured in a radial position using a power setting of 1 kW. The plasma, auxiliary, and nebulizing flows were set at 15, 1.5, and 1.5 L min1, respectively. The viewing height was fixed at 8 mm and the replicate read time was set to 1 second. In order to prevent sample overlap, a 30 second uptake delay and a 15 second inst rument stabilization delay were employed. The peristaltic pump rate was maintained at 15 rpm and the rinse time was set to 10 seconds. Argon (99.5%) was used as the nebulizer gas. Surface water and sediment samples were collected from fourteen sampling s ites in the environment surrounding KSC, as shown in Figure 11. At each site, the surface water samples were collected (n=3) with a disposable glass pipette approximately 10 cm below the water surface. The water was then placed into amber glass vials (40 mL) and stored in the dark at 4 C. Sediment samples (defined as approximately 50:50,

PAGE 13

13 sediment:water) were collected (n=3) and stored in a similar manner. The samples were treated with concentrated nitric acid (2%). Sample properties (temperature, conducti vity, salinity, pH and dissolved oxygen content) for each site are shown in Table 12. The water properties were measured using a Yellow Springs Instrument (YSI) 600XL equipped with a 650MDS reader. Surface water and topsoil samples were collected by Dr. Lou Guillette and his research group at site L (Figure 11) several weeks prior to and fifteen hours post shuttle launch. The pre launch surface water and topsoil samples were collected on 6/10/2009 at 10:20 a.m. The space shuttle, Endeavor STS 127, launch ed from pad 39A on 7/15/2009 at 6:03 pm. The post launch samples were collected on 7/16/2009 at 9:20 am. Prior to the collection of the prelaunch samples, the previous shuttle launch occurred on 5/11/2009 at 2:01 pm. The surface water samples (n=3) were c ollected and prepared as previously described. The topsoil samples (n=3) were collected and prepared by measuring 100 mg, grinding and digesting the soil using a microwave digestion procedure. The microwave digestion was performed using a domestic 1000W mi crowave (GE). The microwave digestion procedure was performed by adding approximately 2.5 mL of concentrated 12M nitric acid in a Parr digestion bomb and heating for two 30 seconds bursts at 300 watts with a 60 second pause in between. Post digestion, the contents were transferred to a 50 mL volumetric flask and diluted to the calibration line with deionized water. The soil pH was determined by adding 10 mL of water to approximately 0.25 g of soil and measuring with a Fischer Scientific Accumet 15. The preand post launch sample properties are shown in Table 1 2. Post launch sediment was not collected during this study. Two statistical methods

PAGE 14

14 were used to classify sample groups, correlation matrices and the average merge method. The average merge method used the variables of distance from the launch pad 39A and correlation. Results and Discussion The surface water and sediment samples collected from the sampling sites shown in Figure 11 represent the sites used to obtain the baseline metal concentrations. A complete understanding of the background concentration levels found at KSC was basic to the interpretation of whether the metals detected were as a result of either the extensive metal usage over the past four decades and those contributions from naturally occurring metal cycles or from recent anthropogenic activity. The most interesting samples were those collected from sampling sites near launch pad 39A (sites 3, 5, and 6) and 39B (site 4), due to the immediate proximity of the sites to the shuttle launch events. A sampling site located further west of launch pad 39A (site 7) was collected from a northern outlet of the Banana River. In addition to those samples collected near the launch pads, samples were collected from several sites (1, 2, 8, 11, and 13) located near important buildings at KSC: the orbital processing facility (OPF), vehicle assembly building (VAB) and launch control center (LCC). The sites located in this region were of particular importance due to the high potential of metal usage and close proximity to the environment. The samples from two sites (sites 9 and 10) were collected from canals adjacent to the roadway just south of the shuttle landing strip. Site 14 was selected based on its extended distance from several of the metal related activities at KSC. Site 12 was a retention pond connected to the KSC landfill and was mostly isolated from the primary water system.

PAGE 15

15 The baseline concentration levels of the twelve most abundant metals (Al, Ba, Ca, Fe, Ga, K, La, Mg, Na, Pr, Sr, and V) detected at sampling sites 1 14 are shown in Figure 12. For the eight metals in Figure 1 2 and 13 there is a distinct difference in baseline concentration levels detected in surface water samples between sites (1, 4, 9, 10 and 12) and sites (2, 3, 5, 6, 7, 8, 11, 13, and 14), with the former sites having a distinctly lower concentration level for each metal. An obvious nonanthropogenic explanation for the elevated metal concentration in the surface water are the sites (2, 3, 5, 6, 7, 8, 11, 13, and 14) access and proximity to coastal seawater. As shown in Table 1 2, the salinity values at each site (except 12) indicate that the water was brackish (0.5 ppt < salinity < 30 ppt), suggesting that the surface water at each of the sampling sites had a degree of salt influence. Seawater and seawater spray are generally saturated ( > 1 mg L1) with the metal salts of Ca, K, Mg, Na, and Sr, though most of the other metal salts (Al, Fe, Ga, La, Mn, Pr, V, and Zn) exist at much lower levels ( < 103 mg L1) [6]. Concomitantly, the trend of having the higher metal concentrations with higher salinity values also follows the trend of increasing water conductivity (please see Table 12), another indicator of seawater influence. In fact, salinity and conductivity are highly linearly correlated (R = 0.9996). Seawater influence is not correlated with the distance of the sites from the Atlantic Ocean, as evidenced by the fact that salinity and distance from launch pad 39A has a correlation coefficient, R, of 0.1818. How ever, with the exception of site 4, the low level concentration sites (1, 4, 9, 10 and 12) were generally distanced from the principal water systems, thus potentially limiting the salt influence, which is further supported by the fact that the salinity and conductivity values for the lower concentration sites were approximately onetenth of those obtained from the more

PAGE 16

16 concentrated sites. Apart from the naturally occurring levels of these metals from seawater and other elemental cycles, some metal content i n the baseline determination could be the result of recent anthropogenic activity. The sediment samples (50:50, water:sediment) collected from each sampling site were chosen to assess the long term metal contamination associated with the several decade hi story of aerospacerelated shuttle activity at KSC. It should be noted that while there was a difference in metal concentrations between sampling sites, there was relatively no significant difference between the surface water and sediment samples collected at the same sites (except for a few instances). Generally, sediment samples are capable of exhibiting a high capacity of accumulating metals over an extended period of time [34]; however, due to the shallow depth and winddriven weather conditions common in Florida, the sediment material is frequently resuspended back into the central body of water [35], thus limiting its potential as a long term pollution assessment option. With large data sets, it was useful to use chemometrics to investigate data classification. Starting with the baseline site data, pair wise relationships were used between the following variables: salinity, concentrations of Na, Mg, Ca, K, Al, Sr, V, Ba, Fe, Ga, Pr and La and the distance between sites measured in mm from launch site 3 9A (center of the hexagon) using the map shown in Figure 11. The correlation matrices for both the surface water and sediment site data are shown in the Tables 13 and 14 (in upper triangular form), as the matrices are symmetric. Because of the large num ber of variables, the R values are shown to 2 decimal places. In the case of both surface water and sediment cases, a strong positive correlation exists for salinity, Na,

PAGE 17

17 Mg, Ca, K, Sr, V and La (0.9 to show a strong positive correlation with salinity, because the cations Na+, Mg2+, Ca2+ and K+ and the anions Cland SO4 2 comprise greater than 99% of the ionic components of seawater [5]. In the case of the surface water samples, Al, Ba, Fe, Ga and Pr are not significantly correlated to the aforementioned variables ( 0.4 suggest that the origin of these elements is anthropogenic. Thus, salinity is likely to be higher at sites with the highly correlated ions. For the baseli ne sediment data, Ba and Ga are insignificantly correlated to all other elements. Aluminum has a moderate negative correlation to all (except Ba) and Pr has a moderate to strong positive correlation with Na, Mg, Ca, K, Sr, V and Fe. Thus, a good choice of parameters to investigate presence of classes for these sites is the set Na, Al, Ba, Fe, Ga and Pr, where sodium is used to represent the salt water component. For the selection of a clustering method, the flowchart in reference [37] was followed. The opensource program ViSta 7 [38] was used for the analysis. These programs can derive a causal relationship between variables, such as concentration and salinity. The first step was to use principal component analysis to obtain a display of the distribution o f the data points. If two principal components account for most of the variation in the data, then a plot of the transformed data in the PC1 PC2 plane may be constructed. Unfortunately, the baseline data requires 3 and 4 principal components to account for 80% (and 84%) and 91% (and 94%) of the total variance, for surface water (and sediment), respectively, so no useful visual display was possible. In order to get a rough impression of the classes present, agglomerative hierarchical cluster analysis was utilized. In agglomerative hierarchical cluster analysis, n isolated objects were

PAGE 18

18 calculated for the distance between objects using a proximity measure (in this case, Euclidean distance). Objects were sequentially linked using the average merge method [37 ]; the end result was a dendrogram. A discussion of the method and mathematical expressions for various merge methods and proximity measures can be found in [39]. Figure 17 shows the dendrogram for the surface water baseline data. For distance drawn at 35 6, 7 clusters are obtained: (7, 14), (2, 11), (4, 12), (3, 8), (5, 6), (1, 9, 10) and 13, a reasonable classification pattern. Notice that cluster (5, 6) contained two of the 3 sites at launch pad 39A. The results suggest that data from sites 5 and 6 shoul d be pooled to give results that characterize launch pad 39A, and results from site 3 should be excluded. Site 4 is classed with site 12, an isolated retention pond. This suggests that site 4, which is physically closer to launch pad 39A, may be useful for monitoring post launch changes at isolated water bodies. Site 13 is probably the best monitor for the effect of OPF, LCC and VAB activities on surface water. Sites 7 and 14 are sites in water bodies connected to two large water bodies: Indian River and Ba nana River. Thus, these sites may be used to monitor changes that will feed into those water systems. The shuttle landing site may be monitored by pooling data from sites 9 and 10, but it is not apparent why site 1 is also in that class. Likewise, it is not obvious why 3 and 8 should be related. The corresponding dendrogram for the sediment bas eline sites is shown in Figure 18 At a distance of 211, the dendrogram gives 8 clusters: (3, 8), (4, 12), (5, 6, 2), (7, 14), (9, 10), 1, 11, 13. There are some c lasses that are the same for surface water and sediment: (3, 8), (4, 12), and (7, 14). For the sediments, 1 does not merge with (9, 10), which was expected intuitively. However, 2 was merged with (5, 6), which was not expected intuitively. For the sediments, 1 and 11, like 13, are single

PAGE 19

19 member classes. Therefore, at a quick glance, it was possible to show which sites were more closely related to other sites. The baseline levels of four trace metals (Al, Ba, Ga, and Pr) detected in sampling sites 1 14 are shown in Figure 14 Ba was detected in most of the sampling sites, though it is generally detected at a higher concentration in the surface water when compared to the sediment samples, suggesting that the source of Ba is most likely seawater related. For Al, relatively high concentration levels were found in the sediment samples, particularly at sampling sites 1 and 3. Pr was detected most extensively in the sediment samples collected near launch pad 39A (sites 3, 5 and 6). For Ga, there was no obvious connection between the sites and suspected metal activity. Surface water samples collected from site L (on Figure 11) were collected both before ( several weeks prior) and after (fifteen hours) the Endeavor STS 127 space shuttle launch. As shown in Figure 15 all of the metals detected had an increase in concentration by a factor of at least two to four times compared to levels detected in the pre launch samples. In addition, several metals (Al, Ba, La, Mn, Pr, and Zn) which were not detected in the pre lau nch surface water samples were subsequently detected in the post launch water. The results support the hypothesis that a distinguishable amount of metals are deposited into the environment as a result of a shuttle launch. The relationship between a space shuttle launch and its corresponding metal deposition has predominantly focused on examining the massive exhaust plume generated during the launch event. Typically, the solid rocket fuel employed by spacecraft, is made up of aluminum powder (fuel), iron oxide (catalyst), ammonium perchlorate (oxidizer), and a polymer binder [30, 40]. Post shuttle launch, the resultant

PAGE 20

20 exhaust plume has been shown to disperse several byproducts, most notably several gases (e.g. gaseous hydrochloric acid, HCl) and aluminum oxide particulates (Al2O3) [40 42]. The amount of hydrochloric acid and aluminum oxide generated from a shuttle launch can reach up to several thousand kilograms (in a 106 m2 area), prompting several studies to examine the potential negative effect of these emissions on the ecosystem [4244]. As a result of the high levels of HCl deposited into the local environment, pH levels drop dramatically. Post shuttle launch, water near launch pads, has been recorded with a pH of as low as 1.5, although this value depends on several factors [45]. Although the measured pH level of the post launch surface water in this study was 6.06, the pH value was most likely considerably lower immediately after the launch, as it has been reported that the neutralizing capabilities o f the ecosystem surrounding launch pad 39A can raise the pH levels up to seven points in 24 hours [45]. Beyond the obvious detriment associated with a highly acidic environment, the lower pH values increase the solubility of metals. As metals enter the env ironment from the post shuttle launch plume, the resultant pH immediately makes the deposited metals more soluble and increases the ability of the metals to absorb into the ecosystem. Several reports have demonstrated that lower pH values lead to an increase in metal uptake by the surrounding wildlife, often leading to deleterious effects [46, 47]. Terrestrial indicators, such as soil, have been useful in providing information regarding potential metal distribution, accumulation, and bioavailability over periods of time [48, 49]. In tandem with monitoring surface water, topsoil samples were collected from site L, as shown on Figure 11, both before and after the shuttle launch. The metal composition (Ba, Ca, Fe, Mg, Sr, and Zn) in the topsoil was generally lower in the post -

PAGE 21

21 launch samples than the prelaunch samples, except for Al, likely due to its abundance in shuttle exhaust plumes. The representative changes in metal concentration in the pre/post launch topsoil samples could be the result of variant env ironmental or sample preparation conditions. In general, environmental indicators (such as surface water, sediment and topsoil) have been useful in providing information on the anthropogenic distribution and integration of metals into the environment. In this study, baseline measurements of metal content were performed at various locations at KSC to determine potential metal deposition as a result of recent anthropogenic activity. Surface water samples collected and analyzed post launch surface water samples showed a significant increase in metal content for all metals over the metal content detected in the prelaunch water samples. The same increase was not observed for the post launch topsoil samples, as the metal concentrations detected in the topsoil post shuttle launch mostly deceased, with the main exception being Al. It is clear that some metals are introduced into the environment as a result of the shuttle launch. However, in an effort to better assess the ecological relationship between space shuttl e activities and metal deposition, a follow up study will be conducted to examine the metal concentrations at KSC in several sampling sites collected over an extended period of time.

PAGE 22

22 Table 11. Calibration results of metals detected in environmental samples Range RSD LOD LOQ Element R 2 (ppm) (%) (ppm) (ppm) Al 396.152 1.0000 0.05 10 11 0.093 0.309 Ba 455.403 0.9999 0.01 10 9 0.006 0.019 Ca 393.366 1.0000 0.2 200 6 0.132 0.440 Er 337.275 0.9997 0.01 10 13 0.015 0.050 Fe 259.940 0.9981 0.05 10 10 0.110 0.367 Ga 417.204 0.9997 0.2 10 11 0.155 0.515 K 766.491 0.9983 0.5 10 10 1.223 4.077 La 333.749 0.9997 0.01 10 9 0.027 0.091 Mg 279.553 1.0000 0.1 200 6 0.046 0.154 Mn 257.610 0.9997 0.01 10 9 0.006 0.021 Na 588.995 0.9999 0.5 200 9 1.230 4.099 Pr 417.939 0.9998 0.1 10 10 0.086 0.285 Sr 407.771 0.9998 0.01 10 9 0.001 0.003 V 309.310 0.9998 0.01 10 11 0.019 0.062 Zn 213.857 0.9997 0.01 10 9 0.051 0.170 The metals shown in the table represent all the metals detected in the environmental samples. The RSD values shown represent the relative standard deviation over the (R2 va lue 0.999 and greater) for the standard ranges listed below but were absent from the environmental samples: Be (313.042), Cd (226.502), Cr (267.716), Cu (324.754), Dy (353.171), Eu (420.504), Gd (342.246), Ho (345.600), Lu (261.541), Sc (361.383), Sm (359. 259), Y (360.074), and Yb (369.419) detected at or below 0.01 ppm; Ce (418.659), Co (228.615), Nd (406.108), Tb (350.914), and Tm (342.508) detected at or lower than 0.05 ppm; In (325.609), Ni (231.604), Pb (220.353), Re (227.525), and Th (283.730) detected at or lower than 0.2 ppm; Bi (223.061), P (213.618) and U (367.007) detected at or lower than 0.5 ppm; and As (193.696), Cs (459.311), Rb (420.179), Se (196.026), and Tl (190.794) were not linear over concentration range. Boron (249.678) was not measured due to the use of borosilicate glass.

PAGE 23

23 Table 12. Environmental c onditions of samples collected at the KSC sites Temperature Conductivity Salinity Dissolved O 2 Sample (C) (MS/cm) (ppt) pH (mg/L) NASA Site 1 18.75 3.54 1.87 7.67 8.73 NASA Site 2 19.22 29.12 18.04 7.93 6.64 NASA Site 3 18.35 33.91 21.31 7.93 7.16 NASA Site 4 19.54 1.27 0.64 7.66 5.55 NASA Site 5 18.52 30.43 18.91 7.95 8.01 NASA Site 6 20.77 24.56 14.96 8.67 7.97 NASA Site 7 23.60 35.96 22.72 8.38 8.85 NASA Site 8 19.08 33.66 21.15 8.56 8.32 NASA Site 9 19.28 4.66 2.50 8.20 9.41 NASA Site 10 19.13 6.70 3.69 7.78 7.75 NASA Site 11 18.83 31.15 19.42 7.95 6.98 NASA Site 12 20.58 0.658 0.32 8.23 9.37 NASA Site 13 18.89 17.51 10.33 7.80 8.42 NASA Site 14 18.13 41.51 26.68 7.89 10.54 Pre Launch Water 29.54 15.83 9.19 7.85 6.89 Post Launch Water 30.05 18.69 11.01 6.06 3.78 Pre Launch Soil N/A N/A N/A 6.50 N/A Post Launch Soil N/A N/A N/A 7.10 N/A The post launch samples were collected behind pad 39A (site L) approximately 15 hours post shuttle launch.

PAGE 24

24 Table 13. Correlation matrix for baseline surface water data Salinity Na Mg Ca K Al Sr V Ba Fe Ga Pr La distance Salinity 1.00 0.99 0.98 0.97 0.99 0.05 0.99 0.99 0.23 0.21 0.05 0.14 0.92 0.18 Na 1.00 0.99 0.96 0.99 0.03 0.99 0.99 0.19 0.28 0.03 0.17 0.91 0.23 Mg 1.00 0.96 0.98 0.04 0.98 0.98 0.15 0.29 0.00 0.16 0.92 0.20 Ca 1.00 0.96 0.07 0.97 0.97 0.15 0.23 0.06 0.27 0.95 0.13 K 1.00 0.10 0.99 1.00 0.18 0.25 0.01 0.20 0.92 0.22 Al 1.00 0.07 0.08 0.25 0.06 0.00 0.22 0.07 0.06 Sr 1.00 0.99 0.17 0.28 0.02 0.20 0.92 0.24 V 1.00 0.17 0.24 0.02 0.21 0.94 0.20 Ba 1.00 0.09 0.60 0.33 0.07 0.30 Fe 1.00 0.35 0.29 0.18 0.15 Ga 1.00 0.75 0.21 0.22 Pr 1.00 0.29 0.15 La 1.00 0.15 distance 1.00

PAGE 25

25 Table 14. Correlation matrix for baseline sediment data Salinity Na Mg Ca K Al Sr V Ba Fe Ga Pr La distance Salinity 1.00 0.99 0.96 0.96 0.98 0.66 0.97 0.99 0.13 0.14 0.20 0.73 0.95 0.18 Na 1.00 0.97 0.97 0.99 0.65 0.98 0.99 0.18 0.16 0.28 0.75 0.92 0.22 Mg 1.00 0.93 0.94 0.62 0.93 0.95 0.20 0.12 0.23 0.63 0.87 0.21 Ca 1.00 0.96 0.66 0.97 0.96 0.13 0.16 0.31 0.76 0.93 0.33 K 1.00 0.64 0.99 1.00 0.22 0.19 0.26 0.78 0.93 0.19 Al 1.00 0.67 0.65 0.30 0.26 0.29 0.60 0.59 0.54 Sr 1.00 0.98 0.17 0.27 0.32 0.82 0.91 0.29 V 1.00 0.17 0.20 0.23 0.76 0.93 0.18 Ba 1.00 0.20 0.31 0.09 0.04 0.11 Fe 1.00 0.18 0.52 0.08 0.15 Ga 1.00 0.20 0.13 0.35 Pr 1.00 0.73 0.43 La 1.00 0.50 distance 1.00

PAGE 26

26 Figure 11. A map of the sampling sites (1 14) located in the environment surrounding Kennedy Space Center. The post launch soil and water samples were collected approximately 15 hours after launch at site L. OPF Orbiter Processing Facility, LCC Launch Control Center. The sections filled in dark gray represent bodies of water. The sites are labeled in order of original sample collection.

PAGE 27

27 Figure 12. Baseline concentrations (in mg L1) of the four most abundant metal s detected in surface and muck water samples at sampling sites 1 14. Error bars are shown as standard deviation of the mean. The concentrations above 10 mg L1 were extrapolated

PAGE 28

28 Figure 13 Baseline concentrations (in mg L1) of the other four abundant metals detected in surface and muck water samples at sampling sites 1 14. Error bars are shown as standard deviation of the mean.

PAGE 29

29 Figure 14 Baseline concentrations (in mg L1) of the four trace metals detected in surface and muck water samples at sampling sites 1 14. Error bars are shown as standard deviation of the mean. The absence of a concentration value or sampling site indicates that the metal was not detected.

PAGE 30

30 Figure 15 Surface water samples (n=3) were collected at site L several weeks prior to and fifteen hours after the launch of the space shuttle Endeavor STS 127. The concentrations of each element are shown in ppm (mg L1). The elements listed in inset (A) describe elements only detected in the post launch surface water (absent in the prelaunch water). Error bars are shown as standard deviation of the mean.

PAGE 31

31 Figure 16 Topsoil samples (n=3) were collected at site L several weeks prior to and fifteen hours after the launch of the space shuttle Endeavor STS 127. The concentrations of each detected element are shown in ppm (mg L1). Error bars are shown as standard deviation of the mean.

PAGE 32

32 Figure 17 Surface water baseline dendrogram. The numbers on the horizontal axis are the sites shown on the map in Figure 1. Each object starts on the horizontal axis with a Euclidean distance of 0. The vertical axis gives the average distance in mm between clusters.

PAGE 33

33 Figure 18 Sediment baseline dendrogram. The numbers on the horizontal axis are the sites shown on the map in Figure 1. Each object starts on the horizontal axis with a Euclidean distance of 0. The vertical axis gives the Wards distance in mm between clusters.

PAGE 34

34 CHAPTER 2 AN EXPERIMENT FOR TH E INSTUMENTAL ANALYSIS LAB Introduction When student s learn about the various forms of pollution originating from anthropogenic practices, an often overlooked and underrepresented factor is metal pollution or emission. Environmental indicators (environmental endpoints) are naturally occurring entities plant or animal organisms as well as nonliving components that can be used to monitor environmental changes, including the state of dispersal and accumulation of metals. The objective of this instrumental analysis laboratory experiment is to demonstrate to stud ents the use of an environmental indicator and atomic spectroscopy for the monitoring of metals derived from a pyrotechnic (fireworks) event and a space shuttle launch. Experimental Background The detection and characterization of anthropogenic pollution i s a highly researched topic following numerous reports over the last four decades demonstrating a direct negative effect of these contaminants on biological systems. What are significant and recent are a series of observations demonstrating that low concentrations (ppt ppb) of various environmental pollutants can have detrimental but not lethal effects on various wildlife species as well as humans. Thus, modern environmental chemistry, with advanced instrumentation and analytical techniques, is helping lead the way in our understanding of the consequences of environmental pollution. An often overlooked source of anthropogenic pollution, especially since the banning of leaded gasoline, is the deposition or emission of metals into the environment. Metal pollut ion can originate from a variety of anthropogenic sources,

PAGE 35

35 including: vehicle degradation and fuel emission, industrial waste and emission, construction and manufacturing waste, and emissions derived from large pyrotechnic events. In the literature, the li st of metals classified as potential waste from anthropogenic activity includes Al, Ba, Cd, Co, Cr, Cu, Fe, Li, Mg, Mn, Na, Ni, Pb, Sr, V, and Zn. A complete characterization of metals is typically summarized by three distinct objectives: the detection of metals in the environment (purpose of this lab experiment), the elucidation of the point source of pollution, and the evaluating of ecotoxicological effect of the metal. Each objective is important in assessing the total burden of metal exposure on the env ironment and human health; however, each objective has its own level of complexity. For the detection of metals in the environment, anthropogenic contributions need to be discerned from native concentrations in the environment (derived from geological or biological cycles). In addition, several environmental factors need to be considered, such as potential wind influence, humidity and precipitation, pH of the sample matrix, and the ability of some metals to bioaccumulate in certain matrices over time. For example, the specific pH of the soil can change the charge state of a metal, potentially converting it from an inactive state to a more readily bioactive and harmful charge state. Most metals are complexed to organic matter or organic compounds at environmentally normal pH levels, and soil is a fluid system with water/moisture, clay, minerals, solidmatter particulates and other components. If the soil is contaminated with materials that lower the overall soil pH, these potentially harmful metals (harmful me aning metals with bioactive oxidation states complexed) now get released into the soil as free metal ions (like Al3+), able to be absorbed into plants

PAGE 36

36 and other wildlife. In normal aquatic ecosystems, some salts (of harmful metals) are not soluble in water unless the pH of the water is dramatically lowered, thus increasing their solubility and ability to be integrated into living organisms. Metals have also exhibited the ability to bioconcentrate in various food webs and, since metals are essentially earths raw materials, they cannot be broken down into less harmful byproducts, like some other anthropogenic contaminants. Furthermore, several metals have no known biological importance (e.g. Al, Ba, Cd, Pb, V) and thus are considered ecotoxic, while others c an be either harmful or essential, based on the level of exposure (e.g. Fe). For the proper detection of several metals within a complicated environmental matrix, the selection and optimization of a method capable of monitoring many elements is paramount. Because of their excellent selectivity and overall low detection limits, the various forms of atomic spectroscopy have for many years been the most widely used methods for elemental analyses. In general, these methods involve conversion of the sample to gaseous atoms and/or ions, which subsequently absorb or emit electromagnetic radiation (EMR). Both qualitative and quantitative analyses are possible, depending on the particular method. The two common means of forming gaseous atoms are the air/acetylene flame and the inductively coupled plasma (ICP). In flame atomic absorption spectroscopy (FAAS), the sample is introduced into a flame via an aspirator. The temperature of an air/acetylene flame (21002400 C) is sufficient to convert most compounds to gaseous atoms, which are primarily in their ground electronic states. The atoms are excited by electromagnetic radiation from an external source and the fraction of the EMR absorbed by the analyte element is related

PAGE 37

37 to the number of analyte atoms in the flame and, hence, to the concentration of the element in the original sample. Because the absorptions of gaseous atoms are extremely narrow energy bands (line spectra), the absorption wavelength is very specific to a certain element. However, to have a measurable d ecrease in the intensity, the incident EMR must have a comparable line width; i.e., it must produce the corresponding emission line of the element. This necessitates use of a separate source, called a hollow cathode lamp, for each element. Flame AAS has the advantages of relatively simple and dependable instrumentation, and it is a reliable, established method for quantitative work. There are, however, several limitations associated with flame work. For the most part, analyses are limited to metals. Althoug h metals constitute most of the elements in the periodic table, there are key nonmetals that cannot be analyzed. The necessity of a separate source for each element precludes the use of FAAS for qualitative analysis. Also, there are a number of interfere nces associated with flame atomization. Many of the disadvantages of FAAS can be overcome, albeit with added expense and instrumental complexity, by using the inductively coupled plasma (ICP) as the atomization medium. The plasma torch consists of three concentric quartz tubes with streams of argon gas through the center tube (also used for sample aspiration) and the concentric spaces. The top of the torch is surrounded by a coil connected to a highpower radiofrequency source. The RF field creates periodi cally changing magnetic fields. The Ar+ ions and electrons (formed initially by a spark from a Tesla coil) move in circular paths around the center of the tube, and the resistance to this movement creates very high temperatures (40008000 C). The intense heat is sufficient to

PAGE 38

38 atomize (and in many cases to ionize) all elements and, furthermore, to excite the outer electrons to higher energy levels. When the electrons return to lower energy states, electromagnetic radiation with wavelengths specific to the element is produced. Thus, the ICP is used for atomic emission spectroscopy (ICP AES). The intensity of the emitted EMR is directly proportional to the concentration of the element in the sample. Because all the elements (including nonmetals) in the sample are excited, ICP AES can be used for qualitative identification of the elements in the sample and for quantitative analysis of several elements simultaneously. In addition, the chemical inertness of the plasma greatly reduces the possibility of interferenc es. In tandem with instrument selection, the appropriate choice of the environmental sample (aquatic, atmospheric, or landbased) to be analyzed is also an important decision. As pollution is dispersed into the environment, it has the potential to enter, i ntegrate, and be distributed among several tiers of the biosphere. Indicators, or specific endpoints, can be used to provide information on the state of pollution dispersal in the environment. Indicators can be earthbound (e.g., soil and water) or biologi cal (e.g., plants, animals, or microorganisms). Indicators are typically defined as being sedentary, inexpensive, accessible, and having a contaminant accumulation mechanism. Soil, a landbased indicator, has been useful as an indicator because of its abil ity to accumulate and retain metals over time. Alternatively, soil pollution can be monitored by biological indicators, such as plants, which can be used to estimate metal concentrations in soil by the metal uptake through a plants root system. Aquatic pollution can be routinely monitored by examining surface and groundwater (along with sediment), whereas several biological species, such as fish and insects, have also been

PAGE 39

39 used as pollution indicators. Atmospheric pollution, typically the first environment al tier exposed, is routinely measured by commercial filters, although several unique bioindicators have been employed. Epiphytes, or mosses and lichens, have no traditional root system and acquire their metals from the atmosphere, thus making them a viabl e pollution indicator. It is clear that several efficient, diverse, and economical monitoring mechanisms are needed to gain a more complete approximation of the total impact of a pollution event. The widespread deposition of metal pollution in the environm ent has led to several reports focused on the relative concentration differences between samples with suspected pollution and those considered controls or environmental reference samples (for example, differences between samples taken from urban and rural settings). Recent technological advances have called for the use of new materials, many of which are metals, thus raising new concerns regarding methods to monitor these new pollution types. One anthropogenic event that utilizes metals is fireworks. Fireworks are generally composed of black powder (a combustible mixture of carbon, sulfur, and potassium nitrate), a carbon source (like charcoal), sulfur, and several metals. Metals are added to fireworks in varying amounts as a result of their ability to add c olor, along with several other important attributes, which include propellant, stabilizing, oxidizing, and fuel properties. Although fireworks are transient in nature, after firework events both resultant aerosol clouds and surrounding environmental samples have been shown to have dramatic increases in harmful gases (SO2, NO, NO2, ozone), VOCs (volatile organic compounds), inhalable suspended matter, and metals. As the aerosol cloud

PAGE 40

40 disperses, these highly concentrated metals can enter the environment. Thus indicators are needed to evaluate the magnitude of these pollution events. The present experiment makes use of ICP AES to analyze metal deposition into environmental samples as a result of both labsimulated and real life largescale combustion events. In this two part study, first we will simulate the airborne metal pollutants originating from sparklers (small scale fireworks) using two environmental endpoints, surface water and Spanish moss ( Tillandsia usneoides ). In the laboratory, the moss samples (p ost metal exposure from sparklers) will be dried, pulverized, and dissolved in concentrated nitric acid using a Parr Microwave Acid Digestion Bomb. The exposed water samples will be acidified prior to analysis. In addition, the different metal uptake by th ese two endpoints will be examined between sparklers of different colors. In the second part of the study, we will be analyzing the metal content in environmental samples taken from the Merritt Island National Wildlife Refuge, which surrounds the Kennedy S pace Center (KSC). Since 1960, the KSC has been the principle launch and construction site for space launches, both manned and unmanned. Two sample matrices (top soil and brackish surface water) were collected from the environment surrounding the launch pads at the KSC before and after a shuttle launch. The set of pre/post launch soil samples will be microwave digested, while the pre/post launch water samples will be acidified (with 2% HNO3). The analysis of samples exposed to a real anthropogenic practice provides a potentially novel platform to monitor real metal pollution in the environment. The specific elements that will be monitored and quantified in this experiment are Al, Ba, Ca, Cr, Cu, Er, Fe, Ga, K, La, Mg, Mn, Na, Sr, V, and Zn.

PAGE 41

41 Procedure ICP AES Instrument Setup (performed by the TA at least 30 minutes before use) 1 Open the Ar tank valve and verify that the tank pressure is at least 500 psi. Turn on the cooler and the room lights (to increase room air flow). 2 Assemble the pump tubing, making s ure to adjust the knurled nuts so the inlet line (front tube) has slightly less pressure on it than the outlet. 3 Turn on the monitor and click the Vista icon. Click Instrument and Status. In addition to the printed status information, the lower right part of the screen should also show a band of blue squares moving across to indicate that the instrument is in the purge mode. Sample Preparation for Sparkler Experiment 1 At least one week prior, Spanish moss was collected (by the TA) from the University of Florida campus. Gloves were used to collect the moss. 2 Accurately weigh four 0.05 gram samples of the dried moss (record weight in notebook and label bag) and place them individually into clean sandwichsized plastic bags (provided by TA). DO NOT CLOSE BAGS 3 Obtain plastic containers (4), green, red, and blue sparklers (3), metal condiment dishes (4), a bottle of MQ water (approx 100 mLs), and gloves. Note that the containers are labeled control, red, blue, and green, and should be used accordingly 4 With TA assistance, take materials and go to the chemistry courtyard. Make sure to check with TA prior to lighting the sparklers. Please read through steps 5 and 6 prior to starting the experiment. 5 Control experiment: The experimental setup is illustrated in Figure 1 (next page). Add one of the moss bags to the container (as shown in the figure). The bag must be open to allow mass transfer. Add 25 mL of MQ water to the metal condiment dish. The dish should then be placed into the container as shown in Figure 1. Put the lid on the container, record the time (approximate time with lid on 1 hour). 6 Green Sparkler Experiment: The experimental setup is the same as in step 5, except for the addition of a lit sparkler (Figure 1). Add one of the moss bags to the container. The bag must be open to allow mass transfer. Add 25 mL of MQ water to the metal condiment dish. The dish should then be placed into the container. With TA supervision, light the sparkler, allowing it to burn for 23 seconds. Immediately douse th e sparkler in the water in the condiment dish (for 2 seconds), then set sparkler in the container as shown in Figure 1, part 2. Make sure that the burnt end of sparkler does not come in contact with the moss bag. Quickly put the

PAGE 42

42 lid on the container and record the time. Allow 1 hour for smoke to disperse in container. 7 Repeat the sparkler experiment for the other two bags of Spanish moss using the same procedure with the other two sparklers. When complete, carefully take all 4 containers (with lids still on) back to the lab. Let the containers sit until the hour is complete. In the meantime, proceed to the next part Element Identification 1. At the Varian Vista ICP, be sure that the aspirator tube is immersed in a flask of fresh MilliQ water. On the computer, the Status screen should be active. With TA assistance, ignite the torch by clicking the yellow torch icon. Observe that the peristaltic pump starts to turn, then stops briefly when the torch ignites, then restarts. Make sure that the plasma color is white (not red). 2. Click the tab labeled Echelle to display the echellogram (should be flat because there is no data being acquired). Then click on the Continuous read icon (green triangle with curved arrow) to start acquiring data. 3. Note the many peaks in the echellogram of the water. In the absence of impurities, these are emission lines of the argon plasma. Verify this by moving the cursor along display lines where the peaks appear. 4. Place the aspiration tube in the multi element ICP tuning solution provided by the TA. Wait about a minute until additional lines appear, especially in the purple region. Click the Stop icon (red box next to the previously green triangles). When the triangles return to green, transfer the aspiration tube back t o the water and extinguish the plasma by clicking the torch icon with the red X on it. 5. Use the cursor to make Zoom boxes around peaks, then place the cursor at the middle of the base of the peaks. In your notebook, verify the lines for the 16 element s at the given wavelengths (Al 396, Ba 455, Ca 393, Cr 267, Cu 324, Er 337, Fe 259, Ga 417, K 766, La 333, Mg 279, Mn 257, Na 588, Sr 407, V 309, and Zn 213 nm). Record the 3 decimal numbers (to the thousandths place) for each element in your notebook (No te: The table on the display is helpful but lists only the most intense lines for each element. A complete listing may be found in the Handbook of Chemistry and Physics .) To return to the full echellogram, click the right mouse button and select Unzoom. 6. Click the X at the top right corner of the 'Instrument Setup' window to exit this screen. (Note: For all other screens use the 'File/Close' pulldown, not the X.) Method Setup 1. On the main Vista window, click 'Worksheet' followed by 'New From', 'Browse', then the worksheet labeled 'Template.vms', and click 'Open'. Enter your initials for

PAGE 43

43 the name of your new worksheet. Then click 'OK', followed by 'OK' to bypass the warning. 2. Click 'Method' followed by 'Edit Method'. Click on the 'Analysis Line' for bismuth (hopefully not present in your samples), and click 'Delete'. 3. Click 'Add' to access the 'Add Analysis Line' screen. Under 'Element', choose 'Ca'. Block the emission line for 393 (with correct decimal) and click 'Apply'. Repeat this procedure for the remaining 15 elements. Then click 'Close'. 4. Click the 'Conditions' tab and verify settings as follows: Power =1 kW; Plasma flow = 15.0 L/min; Auxiliary flow = 1.5 L/min; Nebulizer flow = 0.90 L/min (volume of Ar flowing through the nebulizer; not t he actual sample aspiration rate); Viewing height = 12 mm; Read time = 5 s; Instrument stabilization = 15 s; Uptake delay = 15 s (time for new sample to flush through the aspiration tube and enter the torch); Pump speed = 15 rpm; Rinse time =10 s (time for rinsing between samples); Fast pump = ; # Replicates = 3 (# of 5second readings per sample). 5. Click the 'Standards' tab. Set the 'Calibration mode' to 'Quantitative' and specify 8 standards. Set the 'Correlation Limit' to 0.5 to avoid error messages. Enter the values of the standards in the appropriate boxes (in ppm 0.5, 1, 2, and 10). Don't worry about the calibration parameters; you will not use the calibration in the Vista software. Close the Method Editor by clicking 'File/ Exit'. 6. Click the 'Sequence' tab, followed by 'Sequence Editor'. Specify the correct number of samples (controls and moss/water samples for each colored sparkler, in triplicate, a total of 24 samples 3 moss/3 water/2 controls for each color sparkler) a nd make sure that the 'Begin with calibration' and 'Include blank in calibration' boxes are checked. Then click 'File/Close', and answer 'OK' to save the method in your worksheet. Moss Digestion 1 After the smoke equilibration time frame is completed (1 hour), take the containers to the fume hood. IMPORTANT! Open the containers in the fume hood and wait until the smoke dissipates. Pour the water from the condiment dishes into labeled glass vials. Remove the moss bags from the container. 2 Remove the moss from the bags (wearing gloves) and pulverize the moss in a mortar and pestle. Gently grind the moss to obtain small pieces and add it to dry Teflon sample cups. Be sure to wash the mortar and pestle between moss samples. 3 **Caution: Wear gloves and safety glasses, and shield your body as much as possible with the hood window for all steps involving the sample

PAGE 44

44 digestion procedure.** Add 2.5 mL of highpurity concentrated HNO3 to each cup. Allow the samples to sit in the hood at room temperature for 5 minutes. 4 With TA supervision place one of the Teflon cups in the cylinder of the dry Parr microwave digestion bomb. Screw the cap until it seals on the cylinder, plus an additional 1/8 turn (no tighter). Place the bomb in the microwave oven. For 30 seconds at 30% power, enter 30 Power Level 3 Start. Let it stand for 60 seconds, then heat again for 30 seconds at 30% power. 5 Allow the bomb, now highly pressurized, to sit undisturbed in the oven for 5 minutes. Then place it in ice (no deeper than the cylinder thr eads) for 5 minutes, or until the cap can be loosened easily. Remove the Teflon cup. **Caution: Open in hood, oxides of nitrogen may escape when the bomb is opened.** 6 Repeat steps 4 and 5 if the sample is not completely dissolved. Repeat the entire pro cedure with the remaining Teflon cups (a total of 3 moss samples and a control). 7 Transfer the digested samples to 100 mL volumetric flasks and dilute to the mark with MilliQ water. Consult the teaching assistant if there is any solid residue in the samples. Use an additional flask to prepare a blank containing 2.5 mL of the highpurity nitric acid diluted with MilliQ water. 8 Thoroughly clean all parts of the bomb. Leave the Teflon cups open to dry. 9 Be sure to add 2% HNO3 to the water collected from the condiment dishes (make sure to do this to the blank as well). Sparkler and Water Analysis 1. Click the 'Analysis' tab. Click 'View' and make sure 'Intensity Results' is chosen. Leave the other choices (checked or unchecked) alone. 2. With the aspiration tube in the water flask, ignite the plasma as before. At the top of the element table, click 'Tube' to make all entries yellow. (The yellow background indicates that the highlighted tube will be analyzed. If you need to rep eat a sample later (e.g., after a suitable dilution), remove the yellow from the unneeded tubes by clicking the tube #'s to be omitted.) 3. Click the 'Start' icon (single green triangle). Aspirate the blank, standards, and samples as specified by the softw are. (The computer makes a jingling sound if it thinks you are too pokey.) 4. As the samples are analyzed, the emission intensities will be displayed in the table. An intensity in red indicates that the sample emission is greater than the most concentrated standard (or it may be a software glitch). If the intensity is, in fact, too high, finish reading the sequence. After the sequence is complete, dilute these samples and reanalyze them as described in step 2.

PAGE 45

45 When you have successfully completed the sequence, return the aspiration tube to the water flask and extinguish the plasma. Follow the data processing instructions described in the next section. Data Processing 1. Open the Excel template on the computer (or obtain from TA). 2. Open the data text file s (on the ICP) and select the entire contents (Crtl A), then right click and select copy (Crtl C, do not right click). 3. On the template file, click on the orangecolored cell once. Right click and select paste (or press Crtl V). 4. The computer will automatically calculate the LSRL (least squares regression line) for each element. The template will also determine the concentration of the samples analyzed. The relative standard deviation (RSD) of the intensities (and thus concentration RSD) is also dis played and presented next to the concentration for each element. Intensity information for future samples can be appended to the template. Save the spreadsheet on a floppy in the A: drive. Standard Additions Setup (Barium) 1 For the metal data, prepare a qui ck calibration plot for Ba and determine the concentration in the green sparkler moss sample using the calculated LSRL line. 2 Design a standard additions analysis for Ba using the green sparkler moss sample. If you had to do a previous dilution of the moss sample, then you must use the diluted samples in designing your standard additions analysis. Furthermore, if the spikes would take a concentration out of range, then you must dilute the samples further. Be sure to keep track of your dilution factors. Reme mber that the ICP destroys the sample, so that separate beakers are needed for each addition. Pipet 25 mL aliquots of the sample into three beakers, and add spikes of an appropriate standard to two of them to produce a good standard additions plot. 3 Minim ize Excel and restore the Vista software. In the Sequence Editor, change the # Samples to 4 and uncheck 'Begin with calibration' and 'Include blank in calibration'. The 4 samples are the blank (which must be read as a sample and manually subtracted from the other readings), the untreated moss sample, and the two spiked moss samples. Click 'File/Close' and answer 'Yes' to replace the sequence. Reignite the torch, and follow procedure steps F1F3 to obtain the standard additions data.

PAGE 46

46 NASA Samples 1 Samples were obtained from the location highlighted in Figure 2 2. 2. Obtain the NASA pre(3) and post (3) launch topsoil and surface water samples from the TA. Samples were previously prepared by the TA. Soil samples were microwave digested for 30 second bursts until dissolved in 30% HNO3. The surface water samples were prepared by adding 2% HNO3. Repeat step H.4 and change the number of samples to 13 (pre/post launch soil and water samples, in triplicate, with one HNO3 blank included). Repeat step H.5. Append data to the template. Limits of Detection (LOD) and Quantitation (LOQ) Analysis 1. Restore the Vista software. In the Sequence Editor, change the # Samples to 10. Leave the remaining options unchecked. 2. Follow procedure steps F1F3, using the blank for all 10 "samples". Append the data to the template. Shut Down 1 Consult the instructor to decide if any more measurements are needed. If you are completely finished, flush the tubing with water by clicking the Fast Pump icon (pitcher pump with the blue stream). Wait 30 seconds and return the pump to the normal mode (icon next to 'FastPump'). 2 Extinguish the torch and loosen the pump tubing. 3 Click 'File/Close'. Then click 'Exit/Yes'. Turn off the monitor, but not the computer. 4 After 10 minutes, turn off the cooler. The main power to the ICP remains on all the time. Sample Data Analysis Exercises 1 Prepare a standard calibration summary table containing all 16 elements. In the table, include the element, element wavelength (with decimals), the slope, y intercept, and R2 value for the LSRL range. Attach the main Excel data spreadsheet in an Appendix. Also, prepare 3 calibration plots (for Ba, Al, and Sr). 2 Determine the concentration of each metal using the corresponding LLS lines in the sparkler sam ple solutions (using template) and present them in a table Calculate the average concentrations and their RSDs (for the samples run in triplicate). Some metals have concentrations above the highest calibration

PAGE 47

47 standard; in these cases, extrapolate the line to approximate the concentration (please indicate the metal and samples where this was performed). 3 Using Excel, prepare 3 (one for each color sparkler) pie graphs to show the a verage metal composition found in the water exposed in the condiment dish. For each sparkler color pie graph, include the six most abundant metals in the graph. Compare the relative metal composition between the different sparklers. Remember to account for the blank (control). 4 Analyzing the data from the three different colored sparklers, prepare a table comparing the amounts of each element absorbed into the surface of the moss. Remember to account for the blank (control). Compare the metal findings here to the metal composition found in the water from data analysis #3. Report any substantial % increases of metal concentration found in the mosses exposed to sparklers compared to the control moss. 5 P repare a table highlighting the metals found as a result of sparkler burning. In the table, list the metals, their role in firework usage, and label each metal as either essential or toxic (or unknown) in regards to normal biological function. 6 Explain how the spike sizes for the standard additions method were determined. Prepare a standard additions plot for Ba, and calculate its concentration by this method. Remember that in this analysis the total volume of the solution increased as the additions were made. 7 Calculate the LODs and LOQs for each element (expresse solution). The LODs and LOQs for each element can be calculated using the equation slope of LLS line for the element in question. Consequently, metals are often considered trace when the concentration falls within a range of the LOD and twice the LOD. List any metals (and the sample they are found in) that occur at trace levels. Are there any metals that were detected in the samples that fell below the newly calculated detection limits? Add the LOD and LOQ data to the table mentioned in data analysis #1. 8 Fo r the pre/post launch soil and water samples (from KSC), calculate the average soil, or mg/L for water). Using the RSD percentage, calculate the plus/minus error value. Prepare a bar graph including all the metals detected, include error bars using the plus/minus value. If any additional metals are discovered, add them to table in data analysis #5. 9 State the results and discuss any major or minor sources of random and systematic error. For the element determined by the standard additions method,

PAGE 48

48 compare the result to the average by direct calibration and explain any significant differences. 10. As shown in Figure 3, the uptake of Ba by the Spanish moss increases over time until 60 mi nutes, where there is no more metal uptake. Give a potential explanation for why this occurs. Why is it difficult to trace pollution detected in Spanish moss back to its origin? Give an idea of a follow up study that could be performed to determine the ori gin. 11. Compare the calculated levels of the metals found in NASA soil and water samples to values published in the NASA Environmental Monitoring Memorandum (from reference #7). Be sure to check units on the table. Material Setup Sheet 4 Ziploc Containers (4 cube) 3 Green Sparklers (Black Jack 10) purchased from Mountaineer Fireworks (~ $7 for 3 boxes of 32 sparklers red, blue and green) 4 Condiment Dishes (capable of holding 25 mL) 4 Plastic SandwichSized Bags (quart size) 125 mL of MilliQ Water 12 M N itric Acid (Fisher) 4 Nylon Cups (to fit inside of acid bomb) 4 Parr Microwave Digestion Bombs Household Microwave (nonfood use), 1000 W 100 mL Volumetric Flasks Moss (6 kg, from UF Campus), Soil (3 kg, from KSC), Surface Water (1 L, from KSC) Varian Vist a CCD Simultaneous ICP AES Proper Safety Equipment (glasses and gloves) Preparation of standard solutions to give to the students The standards are prepared from a certified, 48 element, 10.00 g/mL certified standard solution (part number ICP MS 68A A) CAS Numbers: Nitric acid [7697 372]

PAGE 49

49 Table 21. Pre and post launch NASA soil data Scan 1 Scan 2 Scan 3 Average NASA Soil Pre Al 396.152 4177.22412 4195.60303 4199.05371 4190.62695 NASA Soil Pre Ba 455.403 8387.39258 8358.74609 8384.91211 8377.01693 NASA Soil Pre Ca 393.366 17074890 17088808 16894826 17019508 NASA Soil Pre Cr 267.716 6.91052198 7.23555517 8.93896294 7.69501336 NASA Soil Pre Cu 324.754 86.7444 89.8298187 98.741951 91.7720566 NASA Soil Pre Er 337.275 35.1873856 29.1665554 26.7990589 30.3843333 NASA Soil Pre Fe 259.940 559.53949 560.503235 555.492859 558.511861 NASA Soil Pre Ga 417.204 21.1957302 17.5488987 18.5707111 19.1051133 NASA Soil Pre K 766.491 525.208435 525.400696 531.392151 527.333761 NASA Soil Pre La 333.749 722.311035 715.931458 713.939636 717.394043 NASA Soil Pre Mg 279.553 49414.2773 49141.7813 48711.4766 49089.1784 NASA Soil Pre Mn 257.610 71.6230545 69.8985901 72.0107117 71.1774521 NASA Soil Pre Na 588.995 131603.859 133751.609 134067.875 133141.115 NASA Soil Pre Sr 407.771 593423.5 595935.5 594977.063 594778.688 NASA Soil Pre V 309.310 0.31040236 1.8132354 1.40506029 1.17623269 NASA Soil Pre Zn 213.857 633.148499 638.78064 636.332458 636.087199 NASA Soil Post Al 396.152 9446.13672 9403.13574 9351.23047 9400.16764 NASA Soil Post Ba 455.403 4966.02783 5366.2334 5444.59277 5258.95133 NASA Soil Post Ca 393.366 3601439 3414137 3384325.25 3466633.75 NASA Soil Post Cr 267.716 7.1236763 9.07391357 7.49460745 7.89739911 NASA Soil Post Cu 324.754 136.493912 149.814926 160.257767 148.855535 NASA Soil Post Er 337.275 53.0090904 55.3712959 45.5631218 51.3145027 NASA Soil Post Fe 259.940 1330.14941 1332.98438 1323.3728 1328.83553 NASA Soil Post Ga 417.204 2.03914905 5.8641839 7.24724007 5.05019101 NASA Soil Post K 766.491 906.994995 911.763306 920.771545 913.176615 NASA Soil Post La 333.749 140.238586 136.172119 129.689957 135.366887 NASA Soil Post Mg 279.553 80476.1719 81226.3438 79548.5234 80417.013 NASA Soil Post Mn 257.610 91.6176071 94.790329 94.0695953 93.4925105 NASA Soil Post Na 588.995 223370.531 224143.609 227053.156 224855.766 NASA Soil Post Sr 407.771 52609.1563 52032.0703 51810 52150.4089 NASA Soil Post V 309.310 9.92003727 14.8811159 13.0502033 12.6171188 NASA Soil Post Zn 213.857 514.429443 514.291443 500.124542 509.615143

PAGE 50

50 Table 22. Pre and post launch NASA water samples Scan 1 Scan 2 Scan 3 Average NASA Water Pre Al 396.152 359.34848 301.796356 280.255676 313.800171 NASA Water Pre Ba 455.403 5526.39404 5708.14063 5998.38965 5744.30811 NASA Water Pre Ca 393.366 11069021 10760801 10779763 10869861.7 NASA Water Pre Cr 267.716 0.15307447 5.10901356 0.49582961 1.81725623 NASA Water Pre Cu 324.754 53.3998566 48.71978 51.0527878 51.0574748 NASA Water Pre Er 337.275 17.6513309 10.2195444 13.3588514 13.7432423 NASA Water Pre Fe 259.940 164.055283 173.676819 168.088348 168.606817 NASA Water Pre Ga 417.204 5.30978489 0.73424435 15.7079248 7.25065136 NASA Water Pre K 766.491 152352.234 152146.422 152699.031 152399.229 NASA Water Pre La 333.749 436.918854 382.614441 418.17926 412.570852 NASA Water Pre Mg 279.553 3797212.5 3783299.75 3782707.75 3787740 NASA Water Pre Mn 257.610 11.1769199 11.9385109 10.7426376 11.2860228 NASA Water Pre Na 588.995 39179084 39247800 39196724 39207869.3 NASA Water Pre Sr 407.771 744051 739657.813 743913.75 742540.854 NASA Water Pre V 309.310 6570.70898 6574.80908 6551.62598 6565.71468 NASA Water Pre Zn 213.857 16.2117577 15.8237915 13.8798399 15.3051297 NASA Water Post Al 396.152 188.058578 184.839951 165.704895 179.534475 NASA Water Post Ba 455.403 4009.93628 4276.9707 4154.09375 4147.00024 NASA Water Post Ca 393.366 7983985 8192757.5 8031080.5 8069274.33 NASA Water Post Cr 267.716 3.12614679 0.87475407 3.15451193 1.80196822 NASA Water Post Cu 324.754 39.206974 34.9760056 35.8008842 36.6612879 NASA Water Post Er 337.275 10.947607 9.09769535 12.1717844 10.7390289 NASA Water Post Fe 259.940 109.039047 114.117699 109.368713 110.84182 NASA Water Post Ga 417.204 3.1898632 5.73029232 10.5978603 6.50600529 NASA Water Post K 766.491 78778.7422 78684.2344 78973.7734 78812.25 NASA Water Post La 333.749 290.105804 280.850372 267.296112 279.41743 NASA Water Post Mg 279.553 2425276.75 2421784 2381640.25 2409567 NASA Water Post Mn 257.610 79.3476105 76.7427673 78.7408981 78.277092 NASA Water Post Na 588.995 29605182 29474256 29467964 29515800.7 NASA Water Post Sr 407.771 394318.313 392291.813 389276.094 391962.073 NASA Water Post V 309.310 2830.08911 2819.4812 2806.08252 2818.55094 NASA Water Post Zn 213.857 58.5708351 56.0849838 57.5673065 57.4077085

PAGE 51

51 Table 23. Calibration plot data set Element 0.01 g/mL 0.05 g/mL 0.1 g/mL 0.2 g/mL 0.5 g/mL 1 g/mL 2 g/mL 10 g/mL Al 13.41483561 1642.057632 125.8459218 273.4994761 894.824661 1765.09222 3526.90773 13566.2485 Ba 2105.695964 4163.655273 9315.185221 18254.64355 45190.5107 81251.7516 151809.778 570139.022 Ca 11964.09766 9972.271159 4981.470052 5879.147135 46541.8906 103506.586 209504.516 893944.151 Cr 0.83683904 18.95474529 39.21308231 82.91296864 236.692459 444.081029 852.371872 2692.82064 Cu 35.52308655 158.0603282 325.2343903 725.6456451 2110.92612 4127.0971 7971.18385 33614.6249 Er 15.18516636 198.6617422 372.0427084 751.2998495 2029.86137 3920.63269 7646.69023 31939.5024 Fe 19.83016109 4.252353668 10.37694931 50.23242823 182.861477 365.756746 700.928244 2706.60148 Ga 0.197957993 32.64404043 70.81643295 150.8596992 401.381418 771.092152 1527.21268 6621.76374 K 16.84112994 3.00881513 38.30310376 96.27897962 324.124332 641.705315 1264.87231 7450.48237 La 7.288236618 81.77353732 153.4405982 307.7124386 826.169154 1532.65243 2901.64214 9866.85047 Mg 1816.744548 1300.169393 572.952474 820.0936686 5744.24959 12744.143 26830.7804 106129.004 Mn 2.140890757 113.2214266 240.3032748 505.1441765 1395.19886 2673.68275 5175.88612 18377.5718 Na 14900.18624 14948.60864 13827.56576 13101.09342 7787.54264 1624.74154 11151.4049 92501.9238 Sr 399.7492676 9176.67334 19036.98389 38704.40446 104991.868 200515.699 381108.214 1236585.64 V 6.875181039 44.26679389 95.66118272 198.9839519 540.733072 1042.57841 2033.1475 8490.19954 Zn 1.376355489 21.71527036 40.28413836 90.90148608 264.982337 522.84686 1058.80904 4484.37528 Concentrations are known to 4 significant figures

PAGE 52

52 Table 24. LLS fit results for calibration plots Element Correlation Slope Int Al 0.9925 1320.48433 434.8935574 Ba 0.9974 56494.65158 11875.37246 Ca 0.9987 90417.51348 2591.035671 Cr 0.9923 266.3589862 84.30930125 Cu 0.9991 3353.034078 315.5246205 Er 0.9991 3181.351327 347.5433464 Fe 0.9974 270.8621272 29.8157162 Ga 0.9995 660.5027624 52.67497881 K 0.9996 748.9167279 72.25646896 La 0.9950 975.9762417 268.8122864 Mg 0.9976 10741.5146 37.37348912 Mn 0.9962 1824.204206 399.4246576 Na 0.9988 10726.98792 13901.55776 Sr 0.9934 122310.2346 36912.4228 V 0.9991 845.8468624 91.12601526 Zn 0.9992 447.8893501 34.34895802

PAGE 53

53 Table 25. Concentrations of elements determined by external calibration Element NASA Soil Pre NASA Soil Post NASA Water Pre (g/mL) NASA Water Post (g/mL) Al 2.844 6.789 0.09170 0.1934 Ba 0.06192 0.1171 0.1085 0.1368 Ca 188.3 38.37 120.2 89.27 Cr 0.2876 0.2869 0.3097 0.3098 Cu 0.06673 0.04971 0.07887 0.08317 Er 0.09969 0.09311 0.1049 0.1059 Fe 1.952 4.796 0.5124 0.2991 Ga 0.05082 0.07210 0.06877 0.06990 K 0.8006 1.316 203.6 105.3 La 0.4596 0.1367 0.1473 0.01087 Mg 4.574 7.490 352.6 224.3 Mn 0.1799 0.1677 0.2128 0.1760 Na 13.71 22.26 3656.3 27532 Sr 4.561 0.1246 5.769 2.903 V 0.1091 0.1227 7.655 3.224 Zn 1.343 1.061 0.04252 0.05148 Bold answers are nonexistent or below the detection limit of the instrument.

PAGE 54

54 Table 26. NASA Environmental Monitoring Memorandum NASA Soil NASA Water Al 2683 0.4 Ba ND ND Ca 11627 304 Cr 5 ND Cu ND ND Fe 1504 0.3 K 1631 311 Mg 3291 0.04 Mn 10 0.01 Na 13771 7006 V 7 ND Zn 8 ND Soil values in mg/kg (or ppb) Water values in mg/L (or ppm) Soil was taken from saltwater wetland Water was average for brackish water Water analyzed was surface water ND = Not detected

PAGE 55

55 Figure 21. Parts 1(a) and 1(b) illustrate the orientation (and approximate distance) of the moss bag, dish of water, and extinguished sparkler. Part 2 illustrates the dousing of the lit sparkler in the water dish. Part 3 displays the cloud of smoke generated by the extinguished sparkler with a closed lid.

PAGE 56

56 Figure 22. Highlighted location at Kennedy Space Center is behind launch pad 39A. The post launch soil and water samples were collected approximately 10 hours after a shuttle launch. OPF Orbiter Processing Facility, LCC Launch Control Center Filled in sections (in light grey) represent bodies of water

PAGE 57

57 Figure 23. LDR strontium calibration plots for six student groups.

PAGE 58

58 Figure 24. Sparkler metal compositions as determined from ICP measurements on water samples

PAGE 59

59 CHAPTER 3 CONCLUSIONS Summary The concentrations of a large selection of metals have been measured at various sites within the KSC compound. By determining the distances from sites, correlation matrices and dendrograms can also show relations between proximity of metals to specific other metals and to sampling locations. The laboratory experiment provides students with a tangible example of environmental monitoring and demonstrates the potential of environmental indicators for the monitoring of metal pollution. For obvious reasons, the analysis of simulated sparklers and real samples typically generates positive student interest, while the experimental setup allows instructors to adapt the design and concepts to fit their personal laboratory objectives. Furthermore, this laboratory gives the students a hands on experience with innovative analytical techniques and provides the instructor a medium to emphasize the parallels between academic and professional lab work. Moreover, the analysis of real samples helps the students become aware of several environmental monitoring problems and concerns associated with the analysis of real samples. The students also learn several fundamental concepts including: atomic spectroscopy, biomonitoring, microwave digestion, matrix interferences, matrix matching, and detection limits. Future Work The purpose of this experiment was to measure the amount of metal deposition present at sites around the Kennedy Space Center. However, measuring the existing concentrations of elements does not reveal many details about the kinetics of

PAGE 60

60 environmental change nor does it determine if the launches are a source of metal pollution. To determine if the shuttle missions are related to the increases of certain elements, numerous samples will need to be analyzed over a much longer period of time. The planned experiment will measure the deposition of metals across several months and acquire samples for several intervals directly after the launch; samples may be collected each day at the sites adjacent to the launch pad for the first week, then every other day for the week following, and so forth. In addition, routine monitoring of the NASA campus will help to identify any environmental spikes as a result of outside interferences. Reference Acknowledgments I would like to thank the coauthors who contributed to the original papers based on the work done for this thesis. I also would like to thank the Kennedy Space Center and NASA for the permission to coll ect the environmental samples. The pie chart was taken from the report of Maria Redkozubova, with permission.

PAGE 61

61 LIST OF REFERENCES (1) Liu, J.; Goyer, R. A.; Waalkes, M. P., Toxic effect of metals. In Casarett and Doul l's toxicology: The basic science of poisons 4th ed.; Klaassen, C., Ed. Pergamon Press: New York, 1991, 629 681. (2) Domingo, J., Metal induced developmental toxcity in mammals: a review. J. Toxicol. Environ. Health 1994, 42 (2), 123 141. (3) Rai, L. C.; Gaur, J. P.; Kumar, H. D., Phycology and Heavy Metal Pollution. Biol. Rev. 1981, 56 (2), 99 151. (4) Markert, B., Presence and significance of naturally occurring chemical elements of the period system in the plant organism and consequences for future investigations on inorganic environmental chemistry in ecosystems. Vegetation 1992, 103 1 30. (5) The ch emical composition of seawater. Anthoni, J. F., 2006. Web. April 15, 2010. < http://www.seafriends.org.nz/oceano/seawater.htm > (6) Schwochau, K., Extraction of metals from sea water. Top. Curr. Chem. 1984, 124, 91133. (7) Garrett, R. G., Natural Sources of Metals to the Environment. Hum. Ecol. Risk Assess. 2000, 6 (6), 945 963. (8) N riagu, J. O., A global assessment of natural sources of atmospheric trace metals. Nature 1989, 338 (6210), 4749. (9) Nriagu, J. O., Global inventory of natural and anthropogenic emissions of trace metals to the atmosphere. Nature 1979, 279 (5712), 4094 11. (10) Pacyna, J. M.; Pacyna, E. G., As assessment of global and regional emissions of trace metals to the atmosphere from anthropogenic sources worldwide. Environ. Rev. 2001, 9 269 298. (11) Han, F. X.; Banin, A.; Su, Y.; Monts, D. L.; Plodinec M. J.; Kingery, W. L.; Triplett, G. E., Industrial age anthropogenic inputs of heavy metals into the pedosphere. Naturwiss. 2002, 89, 497 504. (12) Sternbeck, J.; Sjdin, A. .; Andrasson, K., Metal emissions from road traffic and the influence of resus pension--results from two tunnel studies. Atmos. Environ. 2002, 36, (30), 47354744. (13) Lough, G. C.; Schauer, J. J.; Park, J.S.; Shafer, M. M.; Deminter, J. T.; Weinstein, J. P., Emissions of metals associated with motor vehicle roadways. Environ. Sci. Technol. 2005, 39 (3), 826836.

PAGE 62

62 (14) Smith, C. J.; Hopmans, P.; Cook, F. J., Accumulation of Cr, Pb, Cu, Ni, Zn and Cd in soil following irrigation with treated urban effluent in Australia. Environ. Pollut. 1996, 94, (3), 317 323. (15) Wong, C. S. C.; DuzgorenAydin, N. S.; Aydin, A.; Wong, M. H., Evidence of excessive releases of metals from primative ewaste processing in Guiyu, China. Environ. Pollut. 2007, 148, (62). (16) Leung, A. O. W.; DuzgorenAydin, N. S.; Cheung, K. C.; Wong, M. H., Heavy Meta ls Concentrations of Surface Dust from e Waste Recycling and its Human Health Implications in Southeast China. Environ. Sci. Technol. 2008, 42, (7), 26742680. (17) Ragaini, R. C.; Ralston, H. R.; Roberts, N., Environment trace metal contamination in Kello gg, Idaho, near a lead smelting complex. Environ. Sci. Technol. 1977, 11 (8), 773781. (18) Dudka, S.; Adriano, D. C., Environmental Impacts of Metal Ore Mining and Processing: A Review. J. Environ. Qual. 1997, 26, 590 602. (19) Loska, K.; Wiechu, D.; Kor us, I., Metal contamination of farming soils affected by industry. Environ. Int. 2003, 30 (2), 159 165. (20) Reimann, C.; De Caritat, P.; Halleraker, J. H.; Volden, T.; Ayras, M.; Niskavaara, H.; Chekushin, V. A.; Pavlov, V. A., Rainwater composition in eight artic catchments in northeastern Europe (Finland, Norway and Russia). Atmos. Environ. 1997, 31, (2), 159170. (21) Kulshrestha, U. C.; Nageswara Rao, T.; Azhaguvel, S.; Kulshrestha, M. J., Emissions and accumulation of metals in the atmosphere due to crackers and sparkles during Diwali festival in India. Atmos. Environ. 2004, 38 (27), 44214425. (22) Vecchi, R.; Bernardoni, V.; Cricchio, D.; D'Alessandro, A.; Fermo, P.; Lucarelli, F.; Nava, S.;Pizzalunga, A.; Valli, G., The impact of fireworks on airb orne particles. Atmos. Environ. 2008, 42, 1121 1132. (23) Wang, Y.; Zhuang, G.; Xu, C.; An, Z., The air poll ution caused by the burning of fireworks during the lantern festival in Beijing. Atmos. Environ. 2007, 41, 417 431. (24) Moreno, T.; Querol, X.; Alastuey, A.; Minguillon, M. C.; Pey, J.; Rodriquez, S.; Miro, J. V.; Felis, C.; Gibbons, W., Recreational atmospheric pollution episodes: Inhalable metalliferous articles from firework displays. Atmos. Environ. 2007, 41, 913922. (25) Attri A. K.; Kumar, U.; Jain, V. K., Microclimate: Formation of ozone by fireworks. Nature 2001, 411 (6841), 10151015.

PAGE 63

63 (26) Ravindra, K.; Mor, S.; Kaushik, C. P., Short term variation in air quality associated with firework events: A case study. J. Environ. Monit. 2003, 5 260 264. (27) Passant, N. Emission factors programme: Task 1 Summary of simple desk studies: Characterisation of Emissions of New Persistent Organic Pollutants (AEAT/ENV/R/1421/Issue1) ; Department for Environment, Food, and Rural Affairs; National Assembly of Wales: the Scottish Ex ecutive; and the Department of Environment in Northern Ireland: 2003. (28) Heinz, A.; Haszler, A.; Keidel, C.; Moldenhauer, S.; Benedictus, R.; Miller, W. S., Recent development in aluminum alloys for aerospace a pplications. Mater. Sci. Eng., A 2000, 280 (1), 102107. (29) Kramer, D. A. Gallium ; U. S. Geological Survey, Mineral Commodity Summaries: 2008. (30) Geisler, R., A Global View of the Use of Aluminum Fuel in Solid Rocket Motors. American Institute of Aeronautics and Astronautics 2002, AIAA Paper 20023748, 1 8. (31) Schmalzer, P. A.; Hensly, M. A.; Mota, M.; Hall, C. R.; Dunlevy, C. A., NASA Technical Memorandum 2000208583: Soil, Groundwater, Surface Water, and Sediments of Kennedy Space Center, Florida: Background Chemical and Physical Characteristics. In National Aeronautics and Space Administration, John F. Kennedy Space Center: 2000, 1 572. (32) Lipartito, K.; Butler, O. R., A History of the Kennedy Space Center University Press of Florida: 2007, 1 496. (33) Martin, T. D.; Brockhoff, C. A.; Creed, J. T., Method 200.7 Determination of Metals and Trace Elements in Water and Wastes by Inductively Coupled PlasmaAtomic Emission Spectrometry. In Environmental Monitoring Systems Laboratory, U.S. Environmental Protection Agency: 1994, 1 58. (34) Soares, H. M. V. M.; Boaventura, R. A. R.; Machado, A. A. S. C.; Esteves da Silva, J. C. G., Sediments as monitors of heavy metal contamination in the Ave river basin (Portugal): multivariate analysis of data. Enviro n. Pollut. 1999, 105 311 323. (35) James, R. T.; Chimney, M. J.; Sharfstein, B.; Engstrom, D. R.; Schottler, S. P.; East, T.; Jin, K.R., Hurricane effects on a shallow lake ecosystem, Lake Okeechobee, Florida (USA). Fund.Appl. Limnol. 2008, 172 (4), 273287. (36) An Introductory Handbook on Basic Probability, Statistics and Excel. Johnson, I., May 2000. Web. 11 Jun 2010. < https://records.viu.ca/~johnstoi/maybe/title.htm > (37) Massart D. L.; Vandeginste, B. G. M.; Deming, S. N.; Michotte, Y.; Kaufman, L., Chemometrics: A Textbook Elsevier: New York, 1988, 383.

PAGE 64

64 (38) Visual Statistics: Seeing Data with Dynamic Interactive Graphics Young, F. W.; ValeroMora, P.; Friendly, M. 2 Feb. 2010. Web. 18 Mar. 2010. < http://www.uv.es/visualstats/Book/DownloadBook.htm > (39) Otto, M., Chemometrics Wiley VCH: New York, 1999; 150 6. (40) Prather, M. J.; Garcia, M. M., The Space Shuttle's Impact on the Stratosphere. J. Geophys. Res., [Atmospheres] 1990, 92 (D11), 18,58318.590. (41) Cofer III, W. R.; Lala, G. G.; Wightman, J. P., Anal ysis of mid tropospheric space shuttle exhausted aluminum oxide particles. Atmos. Environ. (1967) 1987, 21, (5), 1187 1196. (42) Dreschel, T. W.; Hall, C. R., Quantification of Hydrochloric Acid and Particulate Deposition Resulting from Space Shuttle Launches at John F. Kennedy Space Center, Florida, USA. Enviro n. Manage. 1990, 14 (4), 501507. (43) Heck, W. W.; Knott, W. M.; Stahel, E. P.; Ambrose, J. T.; McCrimmon, J. N.; Engle, M.; Romanow, L. R.; Sawyer, A. G.; Tyson, J. D., NASA Technical Memorandum 74109: Response of Selected Plant and Insect Species to Si mulated Solid Rocket Exhaust Mixtures and to Exhaust Components from Solid Rocket Fuels In National Aeronautics and Space Administration, John F. Ke nnedy Space Center: 1980, 1 164. (44) Romanow, L. R.; Ambrose, J. T., Effects of Solid Rocket Fuel Exhaust on Honey Bee Colonies. Environ. Entomol. 1981, 10 (5), 812 816. (45) Provancha, M. J.; Hall, C. R., Ecology and life history of the clown goby inhabiting the upper Banana River, Cape Canaveral, Florida. Environ. Biol. Fishes 1991, 31 (1), 41 54. (46) Spr y, D. J.; Wiener, J. G., Metal bioavailability and toxicity to fish in low alkalinity lakes: a critical review. Environ. Pollut. 1991, 71, (2 4), 243304. (47) Baker, J. P.; Schofield, C. L., Aluminum Toxicity To Fish In Acidic Water. Water, Air, and Soil Pollut. 1982, 18, 289 309. (48) KabataPendias, A., Behavioral properties of trace metals in soils. Appl. Geochem. 1993, 8 (Supplement 2), 39. (49) Lasat, M. M., Phytoextraction of Metals from Contaminated Soil: A Review of Plant/Soil/Metal Interaction and Assessment of Pertinent Agronomic Issues. Journal Hazard. Subst. Rep. 2000, 2 5.1 5.25. (50) Skoog, D. A.; Holler, F. J.; Crouch, S. R. Principles of Instrumental Analysis 6t h Ed.; Thompson Brooks/Cole.: Belmont, CA, 2007, Chap. 7, 8 & 10.

PAGE 65

65 (51) Operating Instructions for Parr Microwave Acid Digestion Bombs ; Parr Instrument Co.: Moline, IL, 1997. (52) Schwochau, K. Extraction of metals from sea water. Topics in Current Chemist ry v.124; Springer: Berlin, Germany, 1984, 91105. (available free online) (53) Vecchi, R.; et al The impact of fireworks on airborne particles. Atmospheric environment v. 42, 2008, 11211132. (54) Szczepaniak, K.; et al Aspects of biomonitori ng using mosses and lichens as indicators of metal pollution. Environmental Research v. 93, 2003, pp. 221230. (55) Sandroni, V.; et al Microwave digestion of sludge, soil, and sediment samples for metal analysis by inductively coupled plasmaatomic emission s pectrometry. Analytica Chimica Acta v. 468, 2002, 335 344. (56) Schmalzer, P. A.; et al NASA Technical Memorandum # 2000 208583. Soil, Groundwater, Surface Water, and Sediments of Kennedy Space Center: Florida, Background Chemical and Physical Characteristics. Dynamac Corporation, NASA Environmental Program Office, June 2000. (available in lab)

PAGE 66

66 BIOGRAPHICAL SKETCH Brian Nocito was born in 1985 in Witchita, Kansas. He recei ved the Bachelor of Science in chemistry with high honors from University of Florida in 2007. He has served as a Research Assistant and a Teaching Assistant in the Department of Chemistry at University of Florida. He received a departmental teaching award during his time as a graduate student.