Document e5LqzJ194KDpZzGz7Jad3YXyp

BACK TO MAIN NON-GLP STUDY: PFOS BACKGROUND SCREEN IN SELECTED WILDLIFE INTERNATIONAL, LTD. AVIAN AND AQUATIC FEED MATRICES WILDLIFE INTERNATIONAL, LTD. PROJECT NUMBER: 454C-101-2 AUTHORS: Raymond L. Van Hoven, Ph.D. Willard B. Nixon, Ph.D. STUDY INITIATION DATE: January 18, 1999 STUDY COMPLETION DATE: September 11, 2000 Submitted to: 3M Corporation Environmental Laboratory 935 Bush Avenue St. Paul, MN 55144 Wildlife International, Ltd. Wildlife International, Ltd. 8598 Commerce Drive Easton, Maryland 21601 (410) 822-8600 Page 1 o f 25 W i l d l i f e In t e r n a t i o n a l , Lt d . 2- - BACK TO MAIN PROJECT NO.: 454C-101-2 REPORT APPROVAL SPONSOR: 3M Corporation TITLE: Non-GLP Study: PFOS Background Screen in Selected Wildlife International, Ltd. Avian and Aquatic Feed Matrices WILDLIFE INTERNATIONAL, LTD. PROJECT NO.: 454C-101-2 STUDY DIRECTOR: Scientist MANAGEMENT: Manager, Analytical Chemistry DATE BACK TO MAIN W i l d l i f e In t e r n a t i o n a l , ltd. -3- PROJECT NO.: 454C-101-2 TABLE OF CONTENTS Title/Cover Page........................................................................................................................................... 1 Report Approval...........................................................................................................................................2 Table of Contents.........................................................................................................................................3 Summary.......................................................................................................................................................5 Introduction.................................................................................................................................................. 6 Purpose 6 Experimental Design. 6 Materials and Methods........... Test Substance.......... Internal Standard....... Reagents and Solvents Test Systems.............. Avian Feed......... Aquatic Feed....... Test Procedures......... Calibration Curves.... Limits of Quantitation Reagent Blanks......... .7 .7 .7 .7 .7 .7 .8 .8 .9 .9 10 Results and Discussion.............................................................................................................................. 10 Avian Feed......................................................................................................................................10 Aquatic Feed........................................................................................................................................... 11 Conclusions................................................................................................................................................ 11 TABLES Table 1 - Typical LCMS Operational Parameters...................................................................................12 Table 2 - Determination of PFOS in Avian Feed......................................... 13 Table 3 - Determination of PFOS in Aquatic Feed................................................................................. 14 BACK TO MAIN W i l d l i f e In t e r n a t i o n a l , ltd .___________________________ p r o j e c t n o .: 4540101-2 -4- TABLE OF CONTENTS ' - Continued - FIGURES Figure 1 - A representative calibration curve for PFOS.........................................................................15 Figure 2 - A representative ion chromatogram of a low-level (0.005 mg a.i./L) calibration standard... 16 Figure 3 - A representative ion chromatogram of a high-level (0.040 mg a.i./L) calibration standard.. 17 Figure 4 - A representative ion chromatogram of a reagent blank sample from the avian feed screen. 18 Figure 5 - A representative ion chromatogram of an avian feed matrix blank sample......................... 19 Figure 6 - A representative ion chromatogram of an avian feed matrix fortification sample................20 Figure 7 - A representative ion chromatogram of an artemia cyst aquatic feed sample........................ 21 Figure 8 - A representative ion chromatogram of a YCT aquatic feed sample...................................... 22 Figure 9 - A representative ion chromatogram of a green-algae aquatic feed sample........................... 23 APPENDICES Appendix I - Diet Formulation - Wildlife International, Ltd. Game Bird Ration..................................24 Appendix II - Personnel Involved in the Study...................................................................................... 25 BACK TO MAIN W i l d l i f e In t e r n a t i o n a l , ltd. -5 - PROJECT NO.: 454C-101-2 SPONSOR: SPONSOR'S REPRESENTATIVE: LOCATION OF STUDY, RAW DATA A N D A COPY OF THE FINAL REPORT: SUMMARY 3M Corporation Rochelle Robideau Wildlife International, Ltd. Easton, Maryland WILDLIFE INTERNATIONAL, LTD. PROJECT NUMBER: TEST SUBSTANCE: STUDY: TEST DATES: 454C-101-2 PFOS Non-GLP Study: PFOS Background Screen in Selected Wildlife International, Ltd. Avian and Aquatic Feed Matrices Experimental Start - January 18, 1999 Experimental Termination - June 9, 1999 TEST SYSTEMS: Avian Feed: WLI Basal Ration (low-calcium diet) WLI Basal Ration + Limestone (high-calcium diet) Aquatic Feed: Artemia Cysts Yeast, Cerophyll, and Trout Chow (YCT) Green Algae (Selenastrum capricornutum) SUMMARY: PFOS concentrations were significantly below limits of quantitation in avian feed used by Wildlife International, Ltd. in avian toxicology studies. Low (ppb-level) concentrations of PFOS were measured in dry artemia cysts used as starting feed ! 1 material in selected aquatic toxicology tests. The concentration levels anticipated in | applied artemia (decapsulated and diluted in saltwater) are not expected to be of consequence in associated chronic effects testing. PFOS was not detected in YCT and green algae feed suspensions used by Wildlife International, Ltd. in chronic aquatic toxicology studies. BACK TO MAIN W i l d l i f e In t e r n a t i o n a l , ltd. 6- - INTRODUCTION PROJECT NO.: 454C-101-2 The integrity of environmental toxicology studies can be compromised if measurable quantities of the test substance under investigation are present in components of the test system. This is especially important in chronic or reproductive studies. In these studies, the potential for toxicological effects from a non-controlled source of the test substance introduced into the test system is greater than those expected in relatively shorter-term acute studies. Random, or non-controlled input sources, may bias the interpretation of toxicological effects from the introduction of controlled doses of the test substance into the test system. The types of feed used to sustain test species in chronic studies are a significant potential source of non-controlled input. Consequently, the screening of the feed to be used in anticipated toxicological effects testing is useful to ensure the success of the studies. In this investigation, selected feed used by Wildlife International, Ltd. for avian and aquatic toxicology studies were screened for PFOS (perfluorooctane sulfonic acid, potassium salt) content. This study was conducted by Wildlife International, Ltd. and identified as Project Number 454C-101-2. The analyses of samples were performed at Wildlife International Ltd. analytical laboratory using high performance liquid chromatography with mass spectrometric detection (LCMS). Blank and fortified avian feed samples were prepared and analyzed between January 18 and February 3, 1999. Blank aquatic feed samples tests were prepared and analyzed between June 8 and 9, 1999. The raw data and a copy of ! the final report generated by Wildlife International, Ltd. are filed under Project Number 454C-101-2 in archives located on the Wildlife International, Ltd. site. R Ll ' PURPOSE The purpose of this study was to determine background concentrations of PFOS, if detectable, in selected avian and aquatic feed to be used in future environmental effect studies. EXPERIMENTAL DESIGN The testing consisted o f either extraction (avian feed and artemia cysts) or dilution (YCT and green algae) o f blank and/or fortified feed materials followed by PFOS analysis by high performance liquid chromatography with mass spectrometric detection (LCMS). BACK TO MAIN W i l d l i f e In t e r n a t i o n a l , ltd ._________________________________ p r o je c t n o .: 454C-101-2 . -7- Quantitation was performed with external standards of PFOS using concentrations that bracketed the expected instrumental concentrations of the samples. Internal standardization was used for avian feed screens only. For each sample set, one calibration curve was generated from the analyses of PFOS standard solutions. For avian feed screens, all calibration standards and samples contained the same nominal concentration (0.100 mg/L) of the internal standard. MATERIALS AND METHODS Test Substance The test substance was received from 3M Corporation on October 29, 1998 and was assigned Wildlife International, Ltd. identification number 4675 upon receipt. The test substance, a white powder, was identified as: FC-95, Lot Number: 217, Expiration Date: 2008. The test substance had a reported purity of 98.9% and was stored under ambient conditions. Internal Standard The internal standard was received from 3M Corporation on July 2, 1998 and was assigned Wildlife International, Ltd. identification number 4526 upon receipt. The internal standard, a granular material, was identified as: 1H, 1H, 2H, 2H Perfluorooctane Sulfonic Acid, Chemical Abstract Number: 27619 97-2. The standard was stored under ambient conditions. The internal standard is referred to hereafter as 4HPFOS. Reagents and Solvents All solvents used were HPLC grade or equivalent. Test Systems Avian Feed Two avian feed (game-bird ration) types were investigated. The feed types differ only in the omission or addition of supplemental calcium. Wildlife International, Ltd. (WLI) Basal Ration is a relatively low-calcium diet employed in acute toxicology studies. WLI Basal Ration + Limestone is a high-calcium diet used in pilot and reproductive studies. A calcium-enriched diet for female birds enhances egg production. The specifications for the ingredients common to these types of feed are presented in Appendix I. BACK TO MAIN W i l d l i f e In t e r n a t i o n a l , ltd. 8- - PROJECT NO.: 454C-101-2 Aquatic Feed The feed used at Wildlife International, Ltd. for early life-stage studies with the fathead minnow (Pimephales promelas) and life-cycle studies with the saltwater mysid (Mysidopsis bahia) consists of decapsulated artemia cysts (brine shrimp eggs) suspended in saltwater. Dry artemia cysts (Bonneville Artemia International, Salt Lake City, UT), prior to decapsulation and suspension in freshwater, were selected for the PFOS screen. Life-cycle studies with the cladoceran (Daphnia magna) employ freshwater suspensions of YCT (yeast, Cerophyll, and trout chow) and green , algae (Selenastrum capricornutum). These freshwater feed suspensions were taken for PFOS ; analysis. Test Procedures The analytical method for the analysis of PFOS in avian diet involved an extraction with methanol (HPLC grade, 99.9+%) and analysis by liquid chromatography mass spectrometry. Each type of avian diet was fortified at 1000 mg a.i./kg PFOS (target nominal concentration) by dry mixing the feed with the test substance, and diluting the fortification to 1.00 mg a.i./kg PFOS (target nominal concentration) with the appropriate unfortified (blank) feed. For each avian feed type, duplicate 10-gram sub-samples of ; : fortified (1.00 mg a.i./kg) and blank avian diets were transferred into 16-ounce French square bottles. One hundred milliliters of methanol was added to each bottle. The bottles were sealed with screw caps, : placed on a tabletop shaker and shaken for a minimum of 30 minutes. The samples were vacuum filtered ' using qualitative filter paper. The avian diet was rinsed three times with methanol into the filtrate. The j | filtrates were then transferred into 200-mL volumetric flasks and brought to volume with methanol. Final > : dilutions were performed by transferring five milliliters of each sample into 10-mL volumetric flasks : partially-filled with NANOpure water. The flasks were fortified with 100 p.L of a 10 pg a.i./mL solution -i of 4HPFOS (internal standard) in methanol. The solutions were brought to volume with NANOpure ; water, mixed and filtered through a 13-mm, 0.2-pm Nylon filter (Gelman Acrodisc, lot 1572) into HPLC autosampler vials. The vials were capped and submitted for LCMS analysis. I.j The analytical method for the analysis of PFOS in artemia cysts consisted of extraction of replicate , , 10-gram samples of unfortified feed with 25 milliliters of methanol (HPLC grade, 99.9+%). ; Approximately three milliliters of each extract was removed from the methanol-saturated feed. A sub sample of each 3-mL extract was ampulated and submitted for LCMS analysis. The analytical method for the analysis o f PFOS in freshwater suspensions of YCT and green algae consisted of dilution prior to BACK TO MAIN W i l d l i f e In t e r n a t i o n a l , ltd._________________________________p r o je c t n o .: 4540101-2 -9- LCMS analysis. Replicate one-milliliter sub-samples of each unfortified aqueous suspension were diluted to 10-mL final volumes with a solution of 50% methanol and 50% NANOpure water containing 0.05% v/v formic acid and 0.100 mg/L of the internal standard. A sub-sample of each dilution was ampulated and submitted for LCMS analysis. Concentrations of PFOS were determined by reverse-phase high performance liquid chromatography using a Hewlett-Packard Model 1100 High Performance Liquid Chromatograph (HPLC) with a Perkin-Elmer API 100LC Mass Spectrometer equipped with a Perkin-Elmer TurboIonSpray ion source. Chromatographic separations were achieved using one of two Keystone Betasil C)8 columns (2-mm I.D., 3-prn particle size). A 100-mm column was used for avian feed screens and a 50-mm column was used for the aquatic feed screens. The instrument parameters are summarized in Table 1. Calibration Curves Calibration standards of PFOS, prepared in a 50% methanol : 50% NANOpure water solution ; containing 0.100 mg 4HPFOS (internal standard)/L and 0.05% formic acid (v/v), were analyzed with the samples. For avian feed samples, the calibration standards ranged in concentration from 0.005 to I 0.040 mg a.i./L. For aquatic feed samples, the calibration standards ranged in concentration from 0.001 to 0.010 mg a.i./L. A minimum of three calibration standards was analyzed with each set of samples. The set of standards was injected at the beginning and end of each run, and one standard was injected, at a ` ` minimum, after every four samples. For avian feed samples, weighted (1/x) linear regression equations [ I were generated using peak area response ratios (PFOS : internal standard) versus the respective 1- concentration ratios (PFOS : internal standard) of the calibration standards. For aquatic feed samples, ' weighted (1/x), linear regression equations were generated using peak area response versus PFOS >- concentration (internal standard not applied). A representative calibration curve is presented in Figure 1. : , The concentration of PFOS in the samples was determined by substituting the peak area response or peak i ; area response ratio (as appropriate) into the applicable linear regression equation. Representative ion , chromatograms of low and high calibration standards are presented in Figures 2 and 3, respectively. i! IJ Limits of Quantitation The method limit of quantitation (LOQ) for analyses of avian feed samples was set at 0.20 mg a.i./kg. The LOQ was calculated as the product of the lowest calibration standard analyzed BACK TO MAIN W i l d l i f e In t e r n a t i o n a l , ltd._________________________________ p r o je c t n o .: 454C-101-2 - 10- (0.005 mg a.i./L), the extraction volume-to-sample weight ratio (0.1 L/0.01 kg), and dilution factor of the matrix blank samples (4). - The LOQ for analyses of artemia cyst samples was set at 0.0003 mg a.i./kg, calculated as the product of the lowest calibration standard analyzed (0.001 mg a.i./L), the extraction volume to sample weight ratio (0.025 L/0.01 kg), and dilution factor of the samples (0.12). The LOQ for analyses of freshwater suspensions of YCT and green algae samples was set at : 0.010 mg a.i./L, calculated as the product of the lowest calibration standard analyzed (0.001 mg a.i./L), and the dilution factor of the samples (10). Reagent Blanks Reagent blanks were analyzed to assess the presence of potential interferences. No chromatographic interferences were observed in the blanks at or above the limit of quantitation. For the . avian feed screen, the reagent blank consisted of an aliquot of methanol diluted with NANOpure water, fortified with internal standard, and filtered as for the study samples. For the aquatic feed screen, the reagent blank consisted of dilution solvent (a solution of 50% methanol and 50% NANOpure water ' containing 0.05% v/v formic acid and 0.100 mg/L of the internal standard). A representative ion chromatogram of a reagent blank sample from the avian feed screen is presented in Figure 4. [ 1 RESULTS AND DISCUSSION Avian Feed The results of the avian feed screen are presented in Table 2. The PFOS concentration of all blank avian feed samples was significantly below the LOQ for the methodology (0.2 mg a.i./kg). The feed fortified at 1.00 mg a.i./kg had a mean PFOS recovery of 83.3 10%. No difference in analytical behavior was observed between the low- and high-calcium diet matrices. A representative ion chromatogram of an unfortified high-calcium diet sample is presented in Figure 5. A corresponding representative ion chromatogram of a fortified sample is presented in Figure 6. BACK TO MAIN W i l d l i f e In t e r n a t i o n a l , Lt d . - 11 - PROJECT NO.: 454C-101-2 Aquatic Feed The results of the aquatic feed screen are presented in Table 3. Concentrations of PFOS ranging . from 0.0009 to 0.001 mg a.i./kg were determined in dry artemia cysts. PFOS was not detected in either the YCT or green algae freshwater suspensions. Representative ion chromatograms of each aquatic feed matrix are presented in Figures 7-9. CONCLUSIONS PFOS concentrations were significantly below limits of quantitation in avian feed used by Wildlife International, Ltd. in avian toxicology studies. Low (ppb-level) concentrations of PFOS were measured in dry artemia cysts used as starting feed material in selected aquatic toxicology tests. The concentration levels anticipated in applied artemia (decapsulated and diluted in saltwater) are not expected to be of consequence in associated chronic effects testing. PFOS was not detected in YCT and green algae feed suspensions used by Wildlife International, Ltd. in aquatic toxicology studies. BACK TO MAIN W i l d l i f e In t e r n a t i o n a l , ltd ._______ _______ - 12- p r o je c t n o .: 454C-101-2 Table 1 Typical LCMS Operational Parameters INSTRUMENT: Hewlett-Packard Model 1100 High Performance Liquid Chromatograph with a Perkin-Elmer API 100LC Mass Spectrometer equipped with a Perkin-Elmer TurboIonSpray ion source. Operated in selective ion monitoring mode (SIM). ANALYTICAL COLUMN: Keystone Betasil Qg column (100 mm or 50 mm x 2 mm I.D., 3-pm particle size) OVEN TEMPERATURE: 30C STOP TIME: 10 minutes FLOW RATE: 0.220 mL/minute MOBILE PHASE: 72% Methanol : 28% NANOpure Water containing 0.1% Formic Acid INJECTION VOLUME: 50.0 pL: avian feed screen 25.0 pL: aquatic feed screen PFOS RETENTION TIME: Approximately 7.5 minutes (100-mm column) Approximately 3.6 minutes (50-mm column) INTERNAL STANDARD RETENTION TIME: Approximately 4.9 minutes (100-mm column) PFOS MONITORED MASS: 498.6 amu INTERNAL STANDARD MONITORED MASS: 426.7 amu BACK TO MAIN W i l d l i f e In t e r n a t i o n a l , ltd. - 13 - PROJECT NO.: 454C-101-2 Sample Number (454C-101-2-) FS-MAB-11 FS-MAB-21 FS-MAS-11 FS-MAS-21 Table 2 Determination of PFOS in Avian Feed Concentration of PFOS (mg a.i./Kg) Fortified Measured NA <LOQ3 NA <LOQ 1.00 0.783 1.00 0.724 Percent Recovery4 NA NA 78.3 72.4 FS-MAB-3*2 FS-MAB-42 FS-MAS-32 FS-MAS-42 NA NA 1.00 1.00 <LOQ <LOQ 0.873 0.951 NA NA 87.3 95.1 Mean = Standard Deviation = N= 83.3% 10.0% 4 `W ildlife International, Ltd. Basal Ration (low-calcium diet). ^Wildlife International, Ltd. Basal Ration + Limestone (high-calcium diet). 3The limit o f quantitation (LOQ) was 0.20 mg a.i./kg calculated as the product o f the lowest standard concentration (0.005 mg a.iVL), the extraction volume to sample weight ratio (0.1 L/0.01 kg), and the dilution factor o f the matrix blanks (4). P ercent recovery = [measured result (mg ai/kg)/nom inal concentration (mg a.i./kg)l x 100._______________________________ BACK TO MAIN W i l d l i f e In t e r n a t i o n a l , ltd. - 14- PROJECT NO.: 454C-101-2 Table 3 Determination of PFOS in Aquatic Feed Sample Number (454C-101-2-) Concentration of PFOS Measured Measured (mg a.i./kg) (mg a.i./L) ART-11 ART-21 YCT-1*2 YCT-22 GALG-13 GALG-23 0.0010 0.0009 NA NA NA NA NA4 NA ND5 ND ND ND `ART = Dry artemia cysts. Bonneville Artemia, Bonneville Artemia International, Salt Lake City, UT. JYCT = Yeast, Cerophyll, and Trout Chow. Freshwater suspension. W ildlife International, Ltd. Lot No. 99-9. 3GALG = Green algae (Selenastrum capricomutum). Freshwater suspension. Wildlife International, Ltd. Lot No. 99-22. *NA = N ot applicable. 5N D = N ot detected Estimated instrument detection limit was 0.0001 mg a.i./L._____________________________ W i l d l i f e In t e r n a t i o n a l , Lt d . - 15 - BACK TO MAIN PROJECT NO.: 454C-101-1 Figure 1. A representative calibration curve for PFOS. Intercept = 1964.6; Slope = 12284942; r2= 0.9920,weighted (1/x). f: W i l d l i f e In t e r n a t i o n a l , ltd. - 16- BACK TO MAIN PROJECT NO.: 454C-101-1 <*v, Figure 2. A representative ion chromatogram o f a low-level (0.005 mg a.i./L) calibration standard. W il d l if e In t e r n a t io n a l , ltd. - 17- BACK TO MAIN PROJECT NO.: 454C-101-1 0 ct <" \* Figure 3. A representative ion chromatogram o f a high-level (0.040 mg a.i./L) calibration standard. W i l d l i f e In t e r n a t i o n a l , ltd. - 18- BACK TO MAIN PROJECT NO.: 454C-101-1 intensity: 2 7 cps u Figure 4. A representative ion chromatogram of a reagent blank sample from avian feed screen (methanol extraction blank). W il d l if e In t e r n a t io n a l , ltd. -19- BACK TO MAIN PROJECT NO.: 454C-101-1 intensity: 508 cps Figure 5. A representative ion chromatogram o f an avian feed matrix blank sample (454C-101-2-FSMAB-4). W i l d l i f e I n t e r n a t i o n a l , Ltd . - 20- BACK TO MAIN PROJECT NO.: 454C-101-1 100 ntensity: 3440 cp s 182 90 80 70 60 50 40 30 20 n 10- 10 25 41 RS 77 135 31 1.25 61 2.45 91 3.66 121 4.86 T------ I -- I 1 211 Scan 8.48 Time t: rj Figure 6. A representative ion chromatogram o f an avian feed matrix fortification sample (454C101-2-FS-MAS-4, 1.00 mg a.i./kg nominal concentration). W il d l if e In t e r n a t io n a l , ltd. -21 - BACK TO MAIN PROJECT NO.: 454C-101-1 ni i i -i Figure 7. A representative ion chromatogram o f an artemia cyst aquatic feed sample (454C-101-1ART-1). W il d l if e In t e r n a t io n a l , ltd. -22- BACK TO MAIN PROJECT NO.: 454C-101-1 Figure 8. A representative ion chromatogram o f a YCT aquatic feed sample (454C-101-1-YCT-1). W i l d l i f e In t e r n a t i o n a l , Lt d . -23 - BACK TO MAIN PROJECT NO.: 454C-101-1 intensity: 112 cps il I ! t- -J Figure 9. A representative ion chromatogram o f a green algae aquatic feed sample (454C-101-1GALG-1). BACK TO MAIN W i l d l i f e In t e r n a t i o n a l , Ltd . -24- PROJECT NO.: 454C-101-2 APPENDIX I Diet Formulation Wildlife International, Ltd. Game Bird Ration1 INGREDIENTS Fine Com Meal Soy Bean Meal, 48% Protein Wheat Midds Protein Base Agway Special, 60% Protein Alfalfa Meal, 20% Protein Dried Whey Ground Limestone Eastman CalPhos Methionine Premix + Liquid Vitamin and Mineral Premix (see below) GL Ferm (Fermatco)2 Salt Iodized Total PERCENT (%) 44.83 30.65 6.50 6.00 4.00 3.00 2.50 0-90 0-60 0.35 0.32 0.25 -- QT0 100.00 VITAMIN AND MINERAL PREMIX AMOUNT ADDED PER TON Vitamin D3 Vitamin A Riboflavin Niacin Pantothenic Acid Vitamin Bn Folic Acid Biotin Pyridoxine Thiamine Vitamin E Vitamin K (Menadione Dimethylpyrimidinol Bisulfite) Manganese Zinc Copper Iodine Iron Selenium 2.000. 0001.C.U. 7.000. 0001.U. 6 grams 40 grams 10 grams 8 mgs 600 mgs 64 mgs 1.2 grams 1.2 grams 20,0001.U. 5.8 grams 102 grams 47 grams 6.8 grams 1.5 grams 51 grams 182 mgs 1 The guaranteed analysis is a minimum of 27% protein, a minimum of 2.5% crude fat and a maximum of 5% crude fiber. Fermentation By-Products BACK TO MAIN W il d l if e In t e r n a t io n a l , ltd. - 25- PROJECT NO.: 454C-101-2*12345 APPENDIX II Personnel Involved in the Study The following key Wildlife International Ltd. personnel were involved in the conduct or management of this study: 1. Raymond L. Van Hoven, Ph.D., Scientist 2. Willard B. Nixon, Ph.D., Manager, Analytical Chemistry 3. Jon A. MacGregor, B.S., Scientist 4. Norman A. Glassbrook, M.S., Senior Chemist 5. Keri B. Leach, B.S., Chemist