Document 2JvjxrYvEKR1Myv32QamaYdor

PHOTODEGRADATION TEST SUBSTANCE Identity:Perfluorooctanoiaccid,ammonium salt;may also be referredtoas PFOA ammonium salt,Ammonium perfluorooctanoateP,FO, FC116, FC-126, FC-169, or FC-143. (Octanoicacid,pentadecafluoro ammonium salt,CAS # 3825-26-1) Remarks: The testsubstance used was 14C labeled(358 dpm/pg). It'psurity was not sufficientclhyaracterizedt,hough currentinformation indicatesitisa mixtureof96.5 - 100% testsubstance and 0 3.5% Cc,,C7, and Cg perfluoroanalogue compounds. Thistestingis currentlybeingrepeated usingcurrentprocedures and best availablepractices. METHOD: Method/guideline followed: Procedure as describedinthe FederalRegister (Volume 43, No. 132-Monday, July10, 1978) by the U.S. Environmental ProtectionAgency. Type (testtype): Simulated sunlight ,GLP (Y/N): No Year completed:1979 LightSource:GeneralElectriFc40BL fluorescenbtlacklight LightSpectrum (nm):Max outputat-360 nm and essentialnloyoutput below 300 nm. Spectralenergy characterizefdrom 290-600 nm. Intensity: Wavelength 290-300 310-320 320-340 340-360 360-380 380-400 400-500 500-600 Wafts Radiated 0.090 0.235 1.410 1.910 2.310 1.680 2.300 0.340 Spectrum of substance (max lambda, max epsilon and epsilon295): Not determined. The testsolutionwas createdby dissolving140.0 mg of thetestsubstance in 2.8 literosfdistillweadter. The resultinsgolutionhad a specifiacctivitoyf 17,320dpm/mL (0.0078pp/mL). Remarks: -Testmedium: Distilwlaetder -Duration3:0 days -PositivCeontrolsN:one -NegativeControlsN:one Photolyzatesamples were collectedafterirradiatiointervalosf0, 1,3,7, 15, and 30 days. Samples were analyzedusinga LiquidScintillatiCoonunter (LSC),TLC-Autoradiographand Gas Chromatography. RESULTS Concentration of Substance: 50 mg/L Temperature *C:22+2*C Degradation %: 0% after30 days Remarks field:No photodegradationofthetestsubstance was detectedin thisstudy. Essentialltyhe same analysisresultswere obtainedforthe 30-day photolyzatesample (no photoproductsformed)as the 0-day sample. Radiocarbon assays at0 and 30 days also indicateno significanatmount of productwas volatilizedduringthe study. CONCLUSIONS No photodegradationproductswere detectedinthisstudy usingsimulated sunlighti,ndicatintghe testsubstance does notundergo photolysis. Submitter: 3M Company, EnvironmentalLaboratory,P.O. Box 33331, St. Paul,Minnesota,55133 DATA QUALITY ReliabilityK:limischranking2.Testingmeets thecriterifaorqualitytestingat the time itwas conducted. However, sample puritywas not properly characterized. REFERENCES 3M TechnicalReport "FC-143 PHOTOLYSIS STUDY USING SIMULATED SUNLIGHT." J.W. Todd, Project9776750202, Report number 002, February 2,1979 OTHER Last changed: 5/24/00 1'3M' FOA 6;@7-1 I-A . TECHNICAL REPORT TO'TECHNICALCOMMUNICATIONSCENTER - 201-2CN Sum m 'Aky L2-@-79_@ ti,nponw-tIfr*PM!Sprintedbo*nO sfdwo~f, und tm copietsoTCC.) Divimo.n Commercial Project service to Report Trio Chemicals TOSCA Division FC-143 PHOTOLYSIS STUDY USING To R. A. PROKOP Agrichemical Project SIMULATED SUNLIGHT 30'6n8 rrowtNumDw 9776750202 map*"mumbw 002 J. W. TODD No Agriche@iical Request 994 SECURITY 0. 0 OPM KEYWORDS: 4S*Iwt Wfm from 3M ThemniL sugpn other Wokmk WMLI CURRENT cwow 140CWI Auftdzedon) OBACTIVE: 3mRECHGEIMSITCARLY Investigate the ohotolyic- stability of ir.radiation time and identify any awolw-emu-mobelis) 43953 U& ofPWO 13 Now ChsmhWs Reparto (3 Yes 99 NO of FC-143 as a function maj'or photoproducts. uto/Hadiography ecOmPosition nvironment as-Chromatography ayer/Chromato- grapby hotolysis adiotracer cintillation RaElPeOr3RtAT4'AwBtoSoTCRoAmCpTw-w (2RD&OD-.25w0ords)Thisabstiseinforrmtiiosncosuibutebdy theTechnicaClomnvjnic"onsCenterto Irradiation of a 50 ppm aqueous solution of FC-143 for 30 days resulted in no detected photoproducts on analysis by thin-layer-cbromatograpy/radioautography, and by gas chromatography of derivatized samples. The irradiation source produced 300 nm and.longer wavelength 1. ight to simulate natural sunlight. ultraviolet lnfOrmatiLoi6aison Initial*: FC-143/PHOTOLYSIS STUDY USING SIMULATED SUNLIGHT INTRODUCTION It is generally acknowledged that manufactured chemicals may-find their way into the environment in various degrees and by various means. Once in the environment they may be destroyed or chemically altered by the action of sunlight (Crosby and Li, 1969). This study investigated the. possible photodegradation of FC-143 in distilled.water on exposure to simulated sunlight (Kohler, 1965). This study was conducted essentially as reco mmended by the Environmental Proection Agency (Federal Register). EXPERIMENTAL 1. Sam2le Materials FC-143 is the ammonium salt of perfluorooctanoic acid. c 7 F 15 COONH 4 The major component is the straight-chain C 7 but some branched chain isomers and other homologs also are present. FC-143 Water Solution-. A 50 ppm solution of FC-143- 14 C (358 dpm/)ig) was prepared by dissolving 140.0 mg of FC-143 in 2.8 liters of distilled water. The resulting solution had a specific.activity of 17,320 dpm/ml (0.0078-/)lC/ml). 2. Analysis Instruments/Materials Liquid Scintillation Counter (LSC) Nuclear-Chicago Mark I Rotary Evaporator B'U*chiRotovapor R Kuderna-Danish Concentrator 10 ml concentrator Reflux column Heated water bath tube - Kontes No. K-570050 - Kontes No. K-569251 -2- Thin-Layer Chromatography (TLC) plates MERCK Silica Gel 60 F-254, 0.25 mm thickness and 20 x 20 cm size lst developing solvent-ethyl acetate/methanol/water, 75/15/10 2nd developing solvent-methyl ethyl ketone/chloroform/acetic acid, 55/30/15 X-Ray Film KODAK NS-2T, 8 x 10 inch size Gas Chromatography System (GC) Gas Chromatograph Column Carrier gas Column temperature Injection part Detector Sample injection - Hewlett-Packard Model 5840 - 6 ft 1/8 in od stainless steel packed with 20% DC 200 silicone/10% BENTONE 34 on ANAKROM ABS (100/110 mesh) - Argon/methane, 95/5 - 800C for 4 minute programed to 180 at 50C/min. - on column, 180*C - electron capture, 300*C - 1 )jl via 10 )il microsyringe DIAZALD DIAZALD is Aldrich Chemical Company's roso-p-toluene-.ulfonamide. It is used to analytical reactant chemical. trade name for N-methyl-N-nitprepare diazomethane, an Diazomethane solution - Alcohol Free. Diazomethane (DAM) was used to convert acidified FC-143 into its corresponding methyl ester Just prior to gas chromatographic analysis. .c F COOH 7 15 CH 2 N 2 c 7 1 15 COOCH 3 N2 (FC-143 acid) (DAM) (FC-143 methyl ester) The DAM reagent used must be free of alcohols or the desired reaction product will not form or will degrade after it has formed. The alcohol-free DAM was prepared essentially as recommended by Aldrich.- A solvent mixture consisting of 35 ml of 2-(2-ethoxyethoxy)-ethanol and 20 ml of diethyl ether was added to a solution of 6 grams of potassium hydrozide dissolved in 10 ml of wate.r. This mixture was -3- placed in a 100 ml long-necked distilling flask fitted with a dropping funnel, an efficient condenser and a water bath at 700C. As the distillation of the ether started a solution of 21.5 g of DIAZALD in about 200 ml of ether was added through the dropping funnel over about 20 minutes. The etheral DAM solution was collected in a 250-ml Erlenmeyer flask cooled in an ice bath. The flask contents were transferred into a bottle, sealed with a TEFLON-lined cap and stored in a freezer. 3. Irradiation The preparative photoreactor used (Crosby and Tang, 1969) is illustrated in Figure 1. The lamp employed was a General Electric F-40BL fluorescent black light with maximum output at about 360 nm and essentially no output below 300 nm (.TableI, General Electric Co.). The tempe'rature was controlled at 22 + 2*C by circulating tap water through flexible plastic tubing wrapped around the reaction chamber. Air was passed through the photolysis solution at 10 ml/min for oxygenation and mixing. The exit port was connected to a vapor trap. The trap consisted of a 6 x 3/4 in. glass tube containing first XAD-2 resin and then charcoal. The photolyzate was sampled after irradiation intervals of 0, 1, 3, 7, 15 and 30 days. The samples were removed through the reactor drain port and were refrigerated until analyzed. 4. Radiocarbon Recovery The photolyzate samples were assayed for radiocarbon by LSC to determine radiocarbon recovery as a function of irradiation time. Similar results were obtained for all samples. Results for the 30 and 0-day samples are presented in Tables II and III, respectively. 5'. Investigation for Photoproducts by TLC-Autoradiography 'Aliquots of the 30 and 0-day photolyzates were reduced in volume 100-fold before TLC analysis. First a 100-ml aliquot of each sample was concentrated to about 5 ml using a rotary vacuum evaporator with a 40-50*C water bath, 50 ml of acetonitrile was added and the rotovacling continued to just dryness (Acetonitrile was added to expeditiously remove remaining water as an azeotrope and thereby minimize possible loss of radiocarbon). The sample solids were dissolved in 3 ml of methanol and -4- quantitatively transferred into a Kuderna-Danish concentrator tube with two additional 3-ml washings. Reflux tubes were attached and the concentrator tubes were immersed in a 65-74*C water bath. The tube contents were concentrated.,to exactly 1 ml. A 10.0 pl aliquot of each sample concentrate (equivalent to 1.0 ml of the original photolyzate solution) was transferred onto a TLC plate. using a 10 ul microsyringe. Each plate was developed two-dimensionally, first with ethyl acetate/methanol/water (75/15/10) and then with methyl ethyl ketone/chloroform/acetic acid (55/30/15). The air-dried TLC plates were then radioautographed. Figures 2 and 3 are pictures of the 30 and 0-day*lradioautographs, respectively. Various component spots and areas on each TLC plate were quantitated for radiocarbon by carefully scraping the silica gel from the plates and LSC. The results are presented in Tables II and III. 6. Investigation for Photoproducts by Gas Chromatography Perfluorocarboxylic salts as FC-143 are not directly analyzable by gas chromatography but can be analyzed if acidified and methylated ,with DAM. The 30 and 0-day photolyzate samples were analyzed by this method (3M Central Research Laboratory). The procedure used is summarized below: Four ml of photolyzate solution was pipetted into a 4-dram vial and acidified with 0.4 ml of concentrated hydrochloric acid. The resulting samples acids were quantitatively extracted with two 2-ml portions of diethyl ether. The ether extracts were combined in a calibrated 10-ml centrifuge tube. One ml of DAM solution was added and the sample allowed.to react for 15 minutes. Excess DAM was then removed by purging the tube contents with a nitrogen jet until the yellow DAM color was almost gone. The sample solution was then diluted to exactly 5 ml with diethyl ether, and analyzed immediately to minimize possible degradation due to any instability of the sample derivative. The chromatograms for the 30 and 0-day photolyzate samples are presented in Figure 4. -5- However several less obvious parameters are important: The DAM soultion should be freshly. prepared p preferably the same day it is used. Several injections of sample may be necessary to passivate the column before accurate'and repeatable results are obtained. RESULTS No photodegradation of FC-143 was detected in this study. Essentially the same analysis results were obtained for the 30-day photolyzate sample (no photoproducts formed) as the 0-day sample. The 30 and 0-day photolyzates had similar radiocarbon assays (Tables II and III) so no significant Amount of radiocarbon was volatilized during the photolysis and so the contents of the vapor trap were not analyzed. Radiocarbon recovqries after sample concentration were good*for the 30-day photolyzate (99%) but less desirable for the 0-day sample dure to physical loss (86%). A repeat concentration of the 0-day sample was not done since it is important only as a TLC reference. Similar. TLC-radioautographs were obtained indicating no change in composition of the 30-day sample compared to the 0-day sample (Figures 2 and 3). Quantitative measurement of radiocarbon in various TLC spots and background areas show similar radiocarbon distribution and good*recovery for the 30-day sample (Tables II and III). Similar gas chromatograms were obtained further confirming the same composition of the 30 and 0-day samples (Figure 4). J. W. Todd -6- REFERENCES Crosby, D.G. and Li, M. 1969. Herbicide Photodecomposition, Chapter 12:321-363 in Degradation of Herbicides, Kearney, P.C. and Kaufman, D.D. (ed), Marcel Dekker Inc. New York, 394 p. Crosby, D.G. and Tang, C.S., J. Agric. Food Chem., 17, 1041,(1969).. Federal Register, Volume 43. No. 132-Monday, July 10, 1978. General Electric Company, Lamp Division, Cleveland, OH .44112. Koller, L.R. 1965. 312 p. Ultraviolet Radiation, 2nd Ed. Wiley, New York. 3M Central Research Laboratory, Analytical Request A-70732. Figure I Photoreactor -7inlet ftna two$ F-408L loweemotbulb Table I SpeCtral Energy Distribution for a GE F40BL black Lignt ',;,,it, Wavelonath 290 - 300 310 - 320 320 - 340 340 -'360 360 - 380 380 - 400 400 - Soo 500 - 600 Watts Radiated 0.090 0.235 1.41 0 1.931l0vo< mosiou a intonalty 20 at Ocut 360 no 1.680 2.300 0.340 -9- Table II Radiocarbon recovered in 30-Day Photolyzate Solution and TLC Plate Scrapings FFIGURE 2) Sample Solution TLC Plate Scrapings DPM/ml Relative % Area Description DPM(per ml)* Recovery 17,320 liol I FC-143 2 Origin. 16,643 66 97 0.4 3 "Background* 288@ Total 16p997 The amount of 14 C radioactivity on the plate is equivalent 1 mi of the original photolyzate solution. 1.7 99.1 to Table III - Radiocarbon recovered in O-Day Photoyzate Solution and TLC Plate Scrapings 'FIGURE 3) Sample Solution DPM/ml Relative % Area TLC Plate Scrapings Description DPM(P r ml)* Recovery 16,643 [102 1 FC-143 2 Origin. 3 "Background" Total 14,493 43 222 14,758 84 0.2 1.3 85.5 The amount.of 14 C radioactivity on the plate is equivalent to 1 ml of the original photolyzate solution. Figure 2 Photograph of TLC Radioautograph 30 Day FC-143 Photolyzate -10- DS-2 co Reference Samiles 50 ug FC-143- 4C @G7,300 dpmlz]e ot photoly FC-143 Origin (DBackground (All areas less spots 1 and 2) DS-1 = Developing Solvent #1, ethyl acetate/methanol/water, 75/15/10 DS-2 = Developing Solvent #2, methyl ethyl ketone/chloroform/acetic acid, 55/30/15 Fgiure 3 Photograph OL' TLC Radioautograph O-Day FC-143 Photolyzate DS-2 :> Reference Samples 50 )jg FC-143-14c (@1-7,300 dpm \,Vot photolyzedd ri co (D FC-143 Origin G) Background (All area less spots 1 and 2) DS-1 DS-2 Developing Solvent #1, ethyl acetate/methanol/water, 75/15/10 Developing Solvent #2, methyl ethyl ketone/chloroform/acetic acid, 55/30/15 Response (D 0 Ct m l,'j*34z,5 0 so 78 aq :s I .iia r_ ct 13 "S (D 0 3.19 I 4 "3 cl (D w L4 C/3 0 (o su ct m. 7.75 0 04 0 R tv F" ct 1-" Eq (D Response 0 ct 7 0 ct 1.0 0) ct 0 2.39 3.19 4.34 ct 6.86 m CD 7.77 N op R