Document 50m9roMpLdVqVYQbex78wKp50

AR226-3112 Humingdon ABIOTIC DEGRADATION: HYDROLYSIS AS A FUNCTION OF pH (PRELIMINARY TEST) Sponsor DuPont Specialty Chemicals Jackson Laboratory Chambers Works Deepwater NJ 08023 USA Research Laboratory Huntingdon Life Sciences Ltd Eye Suffolk IP237PX ENGLAND Draft: 23 December 1998 Final: 2 February 1999 Bffi'Bpas'iSlyanHteed. Does BOB en"a'"i T.WA ^or CONTENTS Page I COMPLIANCE WITH GOOD LABORATORY PRACTICE STANDARDS .............................. 3 QUALITY ASSURANCE STATEMENT...................................................................................... 4 ' RESPONSIBLE PERSONNEL...................................................................................................... 5 I SUMMARY..................................................................................................................................... 6 ! INTRODUCTION....................................................................................................................... 7 '' TEST SUBSTANCE...........................-................--......--..........--.....--..--...........--............ 8 METHODS..............................:.................................................................--...........-...--........-.. 9 RESULTS----........--..........----......................--..................------...................---.......-- 11 DISCUSSION..........----......----...........---..................------.................--..----......--.. 12 CONCLUSION............................................................................ --..--------...--------.......-- 13 Huntingdon Life Sciences COMPLIANCE WITH GOOD LABORATORY PRACTICE STANDARDS Hydrolysis as a Function ofpH The study described in this report was conducted in compliance with the following Good Laboratory Practice standards and I consider the data generated to be valid. The UKGoodLaboratory Practice Regulations 1997 (Statutory Ins^ EC Council Directive 87/18/EEC of 18 December 1986 (Official Journal No L 15/29). OECD Principles of Good Laboratory Practice (as revised in 1997), ENV/MC/CHEM(98)17. A. L. Comb, B.Sc., Ph.D. Study Director Huntingdon Life Sciences Ltd. ......Z.-.^^JW.. Date l) 9aln 'B'e* a A--J @SWWS Ssritt^ Dee Bat le8ntel" TSCA f>sft Huntingdon Life Sciences QUALITY ASSURANCE STATEMENT Hydrolysis as a Function ofpH The following have been inspected or audited in relation to this study Study Phases Inspected Protocol' Date of Inspection 18 August: 1998 Date of Reporting 19 August 1998 Process Based Inspections Hydrolysis 2 December 1998 3 December 1998 Report 15 January 1999 15 January 1999 Protocol: An audit of the protocol for this study was conducted and reported to the Study Director and Company Management as indicated above. Process based inspections: At or about the time this study was in progress inspections and audits of routine and repetitive procedures employed on this type of study were carried out. These were conducted and reported to appropriate Company Management as indicated above. Report Audit: This report has been audited by the Quality Assurance Department. This audit was conducted and reported to the Study Director and Company Management as indicated above. The methods, procedures and observations were found to be accurately described and the reported results to reflect the raw data. -H. Comb, B.Sc. Principal Auditor, Department of Quality Assurance, Huntingdon Life Sciences Ltd. ^ W^Zfi^W \^.i. Date l?w T/A ^ RESPONSIBLE PERSONNEL Huntingdon Life Sciences Hydrolysis as a Function ofpH The following staff member has reviewed this report. T. C. Cowlyn, EurChem., C.Chem., M.R.S.C. (Scientific Manager, Product Characterisation, Eye) The following staff member was responsible for the conduct of the work and reporting of the results. P. Woods, H.N.C. (Scientist, Product Characterisation) ^fflipe^SefflSte^.Powa^effiiWro'raeafiwi SUMMARY The hydrolysis oi^B^^^H^Ks a function ofpH was studied according to EEC guidelines. The preliminary study showed that after 5 days at pH 4,7 and 9 and 50C less than 10% hydrolysis had occurred, equivalent to half-life times (1%)of greater than one year under conditions more representative of the environment (25C). 'as found to be hydrolyticauy stable under acidic, neutral and basic conditions. INTRODUCTION The purpose of this series of tests was to investigate the hydrolytic behaviour o. function of pH. The test was conducted in accordance with the OECD Guidelines for Testing of Chemicals (1981) and the requirements of the Annex to European Commission Directive 92/69/EEC. The protocol was approved by Huntingdon Life Sciences Management on 7 July 1998, by the Sponsor on 17 July 1998 and by the Study Director on 13 August 1998. The experimental phase of the study was undertaken between 9 November 1998 and 27 November 1998. Location of study : Huntingdon Life Sciences Ltd Eye' Suffolk IP237PX England Primary data from the tests performed at Huntingdon Life Sciences and a copy of the final report are stored in the archives of Huntingdon Life Sciences. . BB96ffBteeHM!R TS^A tW Identity: Chemical name: Intended use: Appearance: Storage conditions: Lot number: Expiry date: Purity: Date received: TEST SUBSTANCE Pale yellow slurry Room temperature 2 years from date of receipt 23 June 1998 Bs on sampling a suspension at room temperature and separates into its component phases. Hence test substance for use in this study, the material was wanned to 35 - 40C in order to yield a homogenous solution. ^BBSiSa^'gesTOSeaiSioeas^'e^^^^6^ ^ METHODS PRELIMINARY INVESTIGATION Preparation of buffer solutions Buffer solutions were prepared using the following volumes: pH 4.0 : Disodhun hydrogen orthophosphate dodecahydrate (27.6 g) and citric acid monohydrate (12.9 g) were dissolved in purified water (1900 ml). The volume was adjusted to 2000 ml with purified water. pH 7.0 : Potassium dihydrogen orthophosphate (6.81 g) was dissolved in purified water (1900 ml), 1M sodium hydroxide (30 ml) was added and the pH was adjusted to 7.0 with 1M hydrochloric acid. The volume was adjusted to 2000 ml with purified water. pH 9.0 : Disodium tetraborate decahydrate (33.1 g) and potassium dihydrogen orthophosphate (3.60 g) were dissolved in purified water (1900 ml) and the pH was adjusted to 9.0 with 1M hydrochloric acid. The volume was adjusted to 2000 ml with purified water. The pH of the buffer solutions were measured using a pH meter. PROCEDURE Aliquots (100 ml) of each buffer solution (previously equilibrated at 50C) were measured into reagent bottles containingBUBJi^Happroxunately 180 mg). Due to the acidic nature of the test substance, the pHs of the resulting solutions were adjusted with 1M sodium hydroxide to within 0.05 of the intended pH of the respective buffer. The bottles were purged with nitrogen, sealed and placed in a thermostatically controlled water bath at 50C in the dark. They were held at 50C until sampling was required (after short incubation period of approximately 10 minutes, and then after 2.4, 24 and 120 hours (5 days)). The water bath was monitored during the period of the test to ensure that the test temperature was maintained. The test was performed in duplicate at each pH value. At each sampling time portions (10 ml) of me test solutions were removed and cooled. Aliquots (1 ml) of the samples were pipetted into separate 10 ml volumetric flasks, to which purified water (6 ml) and 0.2M aqueous sodium hydroxide (0.5 ml) were added before diluting to volume with acetonitrile. The final solutions were then analysed by ion chromatography. The pH values of the solutions were measured over the period of the test. g^sa^^^^^^^ ION CHROMATOGRAPHY CONDITIONS Instrument: Dionex GP40 Pump Dionex PED-2 Pulsed Electrochemical Detector Perkin-Elmer ISS 200 Autosampler Dionex ASRS-n Membrane Suppressor Column: PLRP-S (25 cm x 4.6 mm internal diameter) Column temperature: Ambient Mobile phase composition: Aqueous solution containing 2mM ammonium hydroxide and ImM sodium carbonate/ acetonitrile (75:25 v/v) Regenerant solution 50mN aqueous sulphuric acid Flow rate: 1 ml/min Injection volume: 100 ul Detector: Conductivity mode Retention time: Approximately 6 minutes The peak observed at 6 minutes corresponds to the perfluorohexylethylsulphonate ion which, from information supplied by the Sponsor, represents 92 % of the active ingredient. Consequently the ^UIBH^Ilf1 levels component only. me water solubility test samples will be quantified relative to this ^ PREPARATION OF CALIBRATION A stock calibration solution of concentration 132.5 mg/1 of active ingredient was prepared by weighing test substance (106.0 mg) into a 100 ml volumetric flask and dissolving in and diluting to volume with purified water. A sub-sample (50 ml) of me stock solution was transferred to a 100 ml volumetric flask, to which 0.2M aqueous sodium hydroxide (5 ml) and purified water (20 ml) were added prior to diluting to volume with acetonitrile. Calibration solutions in the range 13.25 to 132.5 mg/1 were prepared by dilutions of the final solution with mobile phase. CALCULATIONS The concentrations oi| introduced before and Eter samples the analysed solutions (C^) were calculated from standards icketing standards) by the following equation: sample peak area x standard concentration (mg/1) A mean peak area of bracketing standards The concentrations o equation: in the test solutions (CJ were calculated from the following C,(mg/l) = CA (mg/1) x dilution factor RESULTS Linearity The detector calibration was found to be linear over the range 0 to 132.5 mg/1 of standard solutions m mobile phase with a regression coefficient of 0.9988 (Table 1, Figure 1). Preliminary investigation Results from th^preliminarv investigation showed that there was no significant change in the concentration oj^HfHfffuvhea incubated in pH 4, 7 and 9 buffer solutions at 50C (see Table 2). Less than 10% hydrolysis had occurred, equivalent to half-life times (t%) of greater than one year under conditions more representative of the environment (25C). pH of reaction solutions The changes in pH of the buffer solutions over the period of the test are presented in Table 3. The results show that there were no significant changes in pH of the buffer solutions with time. DISCUSSION Results from the preliminary study showed that the hydrolysis rates at pH 4, 7 and 9 and 50C were such that less than 10% hydrolysis was observed in each case after 5 days. This is equivalent to an environmental half-life of greater than 1 year under each condition investigated. MpySen!fM W^ssMl?8eft ^ CONCLUSION ^alBHBI^H^ The preliminary investigation indicated l ^ neutral and basic conditions. hydrolytically stable under acidic, IgaRB^S^BfeeS. TABLE 1 Standard calibration fo ly ion chromatography Standard concentration (mg/1) 13.25 26.51 53.01 79.25 106.0 132.5 Linear regression (including x = 0, y = 0) x = concentration y = peak area y = 561x + 1460 r= 0.9988 Peak area 8238 16812 32982 47741 60304 74469 80000 70000 4- 60000 450000 4- 40000 30000 -420000 4loooo 4- 0 ^ FIGURE 1 Standard calibration ^qflBHlHby ion chromatography 6.0 80 Concentration (mg/1) TABLE 2 Preliminary investigation results for hydrolysis o1 pH4 Time (hours) 0 2.4 24 120 Sample A 488.7 500.3 487.9 492.1 Concentration, C( (mg/1) Sample B 508.5 519.3 501.6 500.2 pH7 Tune (hours) 0 2.4 24 120 Sample A 483.3 492.5 503.8 492.8 Concentration, C, (mg/1) Sample B 503.6 507.8 513.3 508.3 pH9 Time (hours) 0 2.4 24 120 Sample A 529.9 537.4 529.3 532.2 Concentration, C (mg/1) Sample B 538.1 544.8 542.2 533.4 TABLES pH during hydrolysis tests Nominal pH 4 7 9 Test Preliminary Preliminary Preliminary Temperature (C) 50 50 50 PH Initial 3.96 7.03 9.05 Final 4.02 7.02 8.98 fc