Document gbp3YY9Ve2Eoeog6zVmRxdeaG

J\-R?Z6, 37^3 P-1 DuPont Chemical Solutions Enterprise P. 0. Box 80023 Wilmington, DE 19880-0023 L March 7,2007 0 7 MR I? AH 6= 03 Dear Jim, Thank you for your time in meeting with us February 20th, as well as for the good discussion that ensued. Enclosed please find the additional information you requested on: 1) The comprehensive, peer reviewed study commissioned by DuPont and conducted by Environ on the global fate and exposure potential from DuPont Fluorotelomer products and 2) Information on the studies that DuPont has conducted and commissioned on the biodegradation of fluorotelomer intermediates and products. Specifically, you will find the Wildlife International invoices in Appendix I (outlined in the attached document pages 2 and 3), invoices from ENVIRON in Appendix II (outlined in the attached document page 4), and Academic Studies we have supported in Appendix III pages 9,10, and 19-41 (outlined in the attached document page 5). As well, I have included a document in Appendix IV that reviews the information we have shared with the EPA and at various scientific meetings. Included in this Appendix is the most recent information shared at the SETAC meeting in November. If you would like any of these documents please don't hesitate to ask. As a follow up I would like to arrange a time to discuss these items and their significance for future work with you at your earliest convenience. With best regards, Henry E. Bryndza Technology Directory ;COMiVIMS HO c b DuPont Chemical Solutions Enterprise DuPont Central Research & Development 63070000024/S c. 3 0 c50 -ill Biodegradation studies of fluorotelomer-based polymers in activated sludge, soil, and sediments. W.R. Berti. B.Szostek, R.C. Buck, N. Wang, and J.T. Gannon E. I. duPont de Nemours & Co., Inc. E. Schaefer and R.L. Van Hoven Wildlife International S902103) tvnoiivn TVlif ;UWn03S c(elV linSe300 v 'v^ S, 7 The miracles o f science' Outline Do not cite or quote. Not for further distribution without author approval. Introduction Biodegradation studies in activated sludge Biodegradation studies in soils Biodegradation studies in sediments Biodegradation studies in anaerobic digester sludge Summary Do not cite or quote. Not for further distribution without author approval. Summary Study results to date Soil and Sludge methodologies and analytical methods have been demonstrated No evidence of polymer transformation observed - Inherent Biodegradation in Sludge - 21 Days - Biodegradation in four Soils - 180 Days Ongoing studies Soil Studies continuing to one-year Sediment studies commenced continuing to one year Anaerobic sludge studies to commence shortly Do not cite or quote. Not for further distribution without author approval. Polymeric Product Dispersion Aqueous Dispersion of.... Polymeric Particles 100-200 nm Hydrocarbon Surfactant(s) 80% W ater 20% Polymer "Typical" Polymeric Product wt.% Active Ingredient (~ 20-30 %) wt.% Fluorine (~ 6-10%) ~ 500 ppm Residual Raw Materials - Telomer B Alcohol - Telomer B Olc-fin - Telomer Acrylate Monomer Polymer Mw > 10,000 Do not cite or quote. Not for further distribution without author approval. Product Routes to the Environment S o il (e.g. landfill) -M unicipal and Industrial Waste Landfill Waste-Water -S ludge & Sediment Incineration - Municipal and Industrial Waste -N o PFOA formed under typical municipal waste incinerator conditions Yamada et al. Chemosphere 2005, 61, 974-984. Do not cite or quote. Not for further distribution without author approval. Study Objectives : Sludge, Soils, and Sediments Preliminary studies : - Develop, demonstrate and optimize experimental methods and analytical procedures. Main studies - Assess degradation potential of fluorotelomer-based polymers by monitoring formation of potential products of degradation 8-2 Fluorotelomer Alcohol (FTOH): F(CF2)8CH2CH2OH 8-2 Fluorotelomer Acid (FTA): F(CF2)8CH2COOH 8-2 Fluorotelomer Unsaturated Acid (FTUA): F(CF2)7CF=CHCOOH Perflurorooctanoic Acid (PFOA): F(CF2)7COOH Do not cite or quote. Not for further distribution without author approval. 00 Aerobic Activated Sludge Studies Used experimental set-up for a Modified ZahnWellens Study (OECD 302B) 300 mg DOC as test substance/L 1 g sludge (D.W.)/L Up to 28 days Measured Dissolved Organic Carbon, F-, and specific metabolites - Trapped gasses in C 1 8 resin column - Initial experiments to examine polymer degradation in sludge Do not cite or quote. Not for further distribution without author approval. Inherent Biodegradability : Acrylate Polymer No evidence of polymer transformation observed after 21 days 8-2 FTOH in solution 8-2 FTA PFOA 8-2 FTOH in off-gas 8-2 FTUA 4 5 nmoles 8-2 F T O H m easured in oroduct Day 7 Day 21 p. 10 Do not cite or quote. Not for further distribution without author approval. General Experimental Design : Soil Studies Background Blank Control: no test item added Test Item: test item concentration of 200 mg active ingredient kg-1 dry wt. Abiotic Control: sterilized test medium with added test item concentration of 200 mg a.i. kg-1 DW soil. Spike Recovery Controls: sterilized medium spiked with following analytes: - 8-2 FTOH, 8-2 FTA, 8-2 FTUA, PFOA p . 11 Do not cite or quote. Not for further distribution without author approval. Soil Studies : OECD 307 as a guideline Preliminary Study -T w o test items and one soil under aerobic conditions for 28 days Sandy clay loam from North Dakota; pH 7.9; 1.2 % organic carbon -Dem onstrated experimental and analytical capabilities, recoveries of analytical spikes. -N o evidence of polymer transformation observed Do not cite or quote. Not for further distribution without author approval. Main soil studies : In-progress Four soils - Alfisol: Howard County, Missouri Sandy loam (11 % clay), pH 5.8, Organic carbon 1.4% - Inceptisol: Deer Park (Spokane Co.), Washington Loam (23% clay), pH 6.6, Organic carbon 2.0% - Mollisol: Grand Forks County, North Dakota Sandy clay loam (23% clay), pH 6.9, Organic carbon 2.1% - Ultisol: New Castle Co, Delaware Sandy loam (14% clay), pH 4.8, Organic carbon 2.9% p. 13 Do not cite or quote. Not for further distribution without author approval. Soils Studies Test vessels are glass serum bottles with aluminum foil-lined closures incubated statically at 20C. Soil moisture content assessed regularly by weighing each bottle and adding water as needed to maintain a level of 40 to 60% water holding capacity. A headspace sample from each vessel is passed through a C18 cartridge. The entire contents of the test vessel are then extracted first using acetonitrile and second with an aliquot of a 200 mM NaOH solution. Do not cite or quote. Not for further distribution without author approval. Soils Studies : Main Studies in-progress p. 14 monfhJrementS a* ^ ^ anc* ^ weeks>anc* 1, 2, 4, and 6 - A ll analytes extracted from control (untreated), treated live treated Ssoils,eeLaacnhh rseppil.kiceadt.e(wd 't!whiacle1 analytes, no test substance) sterile -- FTOH measurements of headspace samples " biomass ( m 2 Status 2 C n,ent f ,reatmen,s' -T e s t systems working well; fast mineralization of 14C-qlucose- moisture content constant (~50% WHC) a - Changing to LC/MS to determine 8-2 FTOH in soil extracts ~ sarmjles^68 'n COntrols' 8-2 FT0H not measured in headspace p. 15 Do not cite or quote. Not for further distribution without author approval. Recoveries from four soils 120 Includes all four soils incubated under sterile 100 conditions 80 Spikes i 60 -8 -2 FTOH: 250 ug/Kg f -Acids: 10 ug/Kg 40 Average recoveries up to 6 months - 8-2 FTOH up to 60 days 70% and greater. 20 0 8-2 FTOH 8-2 FTA 8-2 FTUA PFOA Do not cite or quote. Not for further distribution without author approval. Recoveries from Soils up to 180 days Four soils, sterile conditions Recoveries of PFOA and 8-2 FTUA > 80% 8-2 FTOH and 8-2 FTA recoveries decreasing with time. - Not recovered - bound residue 8-2 FTOH * 8 - 2 FTA 8-2 FTUA B P FO A 0 7 14 28 60 120 180 Days p. 17 Do not cite or quote. Not for further distribution without author approval. Recoveries from Soils up to 180 days Average recoveries up to 6 months under sterile conditions - 60 days for 8-2 FTOH. Recoveries of 8-2 FTOH variable Differences by soil type 150 125 0( /) 0> 75 oo a0: 50 25 0 Alfisol Inceptisol Mollisol Ultisol p. 18 Do not cite or quote. Not for further distribution without author approval. S o il: Acrylate Polymer Product 8-2 FTOH concentration Four soils combined decreases indicating biodegradation After 180 days, PFOA is less than the 8-2 FTOH added to soil as an residual Month 6 samples taken. Continue to one year No evidence of polymer transformation observed 130 pinole equiv.8-2 FTO H *K g_1 soil within polymer LOQ of 8-2 FTA and 8-2 FTUA < -0 .0 0 4 pmoles-Kg-1 8-2 FTO H not measured at 120 and 180 days PFOA pmole/Kg soil Acrylate Polymer Product oval. 2.11umole/Kg residual 8-2 FTOH 210 resTduas^FT^f631^ t0 be leveling off at the concentration of PFOA formation is only from the degradation of residual 8-2 FTOH and not from the polymer. No evidence of polymer transformation observed p. 20 Do not cite or quote. Not for further distribution without author approval. Summary - Soil Studies No evidence of polymer degradation observed thus far Demonstrated analytical methods & study operation Sterile spike recoveries - Good overall recoveries, especially for PFOA and 8-2 FTUA - Validating alternative method and will reanalyze samples for 8-2 FTOH 8-2 FTOH was not found in the head space of any samples, - including sterile soils to which it had been fortified at 0.54 pmole kg-1(250 pg kg-1, LOQ < 0.0125 pg mL'1headspace). Acrylic Polymer - 8-2 FTOH, 8-2 FTA, 8-2 FTUA, and PFOA extracted from soils can be accounted for by transformation of fluorinated residuals alone. - Similar results for other polymer products under study p. 21 Do not cite or quote. Not for further distribution without author approval. Sediment Studies Treatments and methods for the sediment similar to soil studies. Sediment and water added to each test vessel - watersediment volume ratio between 3:1 and 4:1 ; the minimum sediment layer is ~ 2 cm. Headspace gases continuously purged a low air flow rate; passed through a C18 cartridge. Anaerobic test vessel conditions are imposed as in the soil test. In addition to headspace and sediment extract samples, separate aqueous samples are collected and analyzed. p. 22 Do not cite or quote. Not for further distribution without author approval. Sediment System Studies : OECD 308 Guideline Preliminary Studies : complete - In-life completed (28 days) - Anaerobic sediment from Turkey Creek (Talbot County, MD USA) High organic carbon content (6.4% O C), pH 5.6, and fine texture (loam) - Changing to LC-MS (from GC-MS) for 8-2 FTOH to improve analytical after validating method Main Study - Review preliminary study results for recoveries once 8-2 FTOH analysis complete and revise protocol - 2 sediments Aerobic sediment from Choptank River (Denton, MD USA) Low organic carbon content (0.5% OC) and a course texture (sand). S am e source of anaerobic sediment as that used in preliminary study - 12 month duration; may extend to 18 months depending on data from soil studies Do not cite or quote. Not for further distribution without author approval. Preliminary studies In anaerobic aquatic Spike Recoveries One sediment, sterile conditions Good recoveries of PFOA and 8-2 FTUA Do not cite or quote. Not for further distribution without author approval. Preliminary studies in anaerobic aquatic sediments: Spike Recoveries 100 80 60 9 D8C 40 20 0 8-2 FTOH Sediment Water Day 0 1" Day 28 One sediment, sterile conditions Low recoveries of 8-2 FTOH Recoveries of 8-2 FTA inconsistent 200 ,, 150 SJ 100 o u V * 50 0 8-2 FTA DayO Day28 p. 25 Do not cite or quote. Not for further distribution without author approval. Summary - Preliminary sediment studies No evidence of polymer degradation observed Low recoveries of 8-2 FTOH from spike recovery control systems -Validating LC-MS method (from GC-MS) for 8-2 FTOH and reanalyze samples Revising and finalizing protocol for main study -A ssess ability of test vessels and systems to contain analytes of interest, especially 8-2 FTOH p. 26 Do not cite or quote. Not for further distribution without author approval. Anaerobic Biodegradability in Digester Sludge Study O ECD 311 Guideline Preliminary Study -Develop and validate analytical methods in digester sludge -Protocol under review 1 anaerobic digester sludge Incubate at 35 degrees C Sample on days 0, 14, and 28 p . 27 mm TMmimeleso jscience' Biodegradation studies of fluorotelomer-based polymers in soils. Subject to Copyright Do not cite or quote without author's written permission. -- C- Buck1' W ' f?1usselM' B- Szstek1, N. Wang1, E. Schaefer*, R. Van Hoven* 1 fc.1. duPont de Nemours & Co., Inc. Wilmington, Delaware U S A VV/W/r/i- International, Ltd. Abstract 0 1 py mw. in ih environmnt i . of intere io detonine if they mtv be e p o te n ti w of p.rHuortctoicytic edd. (PFCAs). W . neve contfuctea udiee pn a llu o ro W m rw S ild tnaaa potymera can tra libarlal t'aTd and tantoaformad to ePhFeCthAearthe tluorotelomer moiMee covaltnlt1y bondW F r . r n y t.Jn.fadyl an un. . control, I (m a y a M .) ta tm a n la cort.nm g tb . teat aubaUnca. . ,, . ST nd i l i r r t S S* " '" " * * f "k, a * " * * " to oaaar. rocorroila * s *P-lo haadapaca and a d aamplaa . . . cdacted Tht L S 2 * 2 S 5 - T r ,b* l* n? " " * * rawmatenata Ih . knovm td degr.d. to th . P F cS a ^S ^M a d "''." ' T l i ! ? " * *t o 15 mon* " * " uwng a Mnetjc dagradaton moda! ' y? * TM >ekjvy trom banalormaton of th roaidu. uorotalorner T I , * " nf M e ? ton * " * P ly " f degradadon contrfbutedto PFCAa obaerved Th. eetimetad nuoroecryiet* pofymer degradation haif-Jrfe w m > 10,000 yeara. Introduction <PF" ` [ h* v* b" " " " d " dtdy p rn .n t in the enylronmm< Reoarrlty a c om p, picture of PFCA aourcaa haa been revrewadf Ditact emiaaiona of PFCAa are the targeet arxaoa of mobal hiatorte PFCA emiaaiona. tndract PFCA aourcaa, or -praeuraor.-, indudad pcrfluoradkyl autfonyt- and ItuorotetomerAraMd aubatancaa. For thaaa Indiract aourcaa. raaldup unreaded raw matarlda and Im purltn u ? r . P' a potent aourc. of PFCAa A key uncartdnty In the w u a m e n t fluoroteiom^aa.d prodrda, l g y cempnamt of pylic pdym .. or perlluorodlnrtaulfonyFbaced produrda detaada In the enyironment to form PFCAa. In order for thie to occur the petymer brrdrbon. and/or tha covalent bond or -linkage- between the fC S td o m e r or perftuorodkyl JfonW functionality and the polymer bactoone would have to be aevered. * Biodagradaton ta a rdorm dion rout, th wig detemyn. polymar .01% f . . A tm d.d numb of experimental biodegradation etudes have been conducted on fluorotejbfftr f iS io i (FTOH), a residual raw matenal, which have identified transformation products that can be u a fiflb p S e polymer degradation,* The present study was designed to determine whether and to what extent a flaWoedfcOte polymer derived from fluorotelomer alcohol degraded in aerobic soats to form |-- " t----irti/nafo 2 Wildlife International, Ltd., Easton, Maryland. U.S.A Study Methodology OECD 307 as a ouldeOne 4 soils, aerobic and anaerobic conditions Initially. ? Measurements at 0,1 , 2 weeks; 1, 2,4 ,6 , , 12,15, 1*. 24 m o h ti is * Analyzed 12 and 1* month samples for 7-3 A dd and 7-2 sFTOH. Completing I I months sampling and analysis. Find samples to be taken at 24 months. le s t Sofia 1. Alflacl: Howard County, Missouri Sandy loam (11% day), pH 5.1, Organic carbon 1.4% 2. Incept)soi: Deer Perk (Spokane Co.), Washington Loam (22% day), pH 8.5, Organic carbon 2.0% 2. M dllsoi: Grand Forks County, North Dakota Sandy d a y loam (22% day), pH 5.5, Organic carbon 2. 1% 4. Utdsd: New Castle Co, Delaware Sandy loam (14% day), pH 4.4, Organic carbon 2.% Generd Enwdnw uw h ||g n Background Blank Control: no test Item added Teat Item: test Item concentration o f 200 mg active Ingredient kg-1 dry w t soil AMode Control: sterilized test medium with added test Item concentration o f 200 mg a.l. kg-1 DW sod. Spike Recovery Controls: sterilized medium spiked with following endytes: 5-2 FTOH, 5-2 FTA, ft-2 FTUA, PFO, PFN, PFD, PFU, 7-2 SFTOH, 7-3 FTA Test vessels ere glass serum bottles with aluminum foB-lined closures incubated statledlv at20*C. 1 Sell moisture content assessed regulwly by wdghlng each botde and adding water as needed to maintain a level o f 40 to *0% water-hddlna capedty. A headspace sample from each vessd Is passed through a C14 cartridge Tha entire contents of the test vessd are then extracted first using acetonitrile and second with an dlq u o t o f a 200 mM NaOH solution. AE Mass Balance Interpretation Alcohol Equivalents (AE) , T7firmi AP roT6 Poster presented at SETAC North American Meeting November 2006 Montral, Canada Kinetic Modeling ]Potymar Dagndation KltMtic Modal a*!KSona p<*,Tn*resatrao tpnnsbM >lu n m ii ~| ? itsocndstool/inw>rt*fssrwg lotofn.ofCA j Pofynw. [gradati) Pathway Eguabgna F r iy s e n (kl*e'Fl N iM : MW . (kl*e*P|-|kt*|*AI A-: M e lM . (tt-f-A I Optimisa ONLYdagncfatlon o* Raaldual Matarialatoforni PPCA WCAI n taUMMM* tteMM ONLY Optimisa ONLYdagradatlon of Potymar to form PFCA PK* to PdpeOtodentCHY _____ L u r i ~ fc - Test Substance & Degradation Pa*dways Fluorotelom er-based Acrylate Polymeric Product Test Substance An aqueous dispersion of fluoroscrytsts polymer in wetsr - FKoroMlemer owytatomonomer omutolonpofrmartzrt MKhottier mcnomwi - Product process Composition - Fluoroecryhte polymer - Hydroesrton sufsetants -Wile* - Residual Rsw MatsMeb endItrvurtOcs <31 ^(SymeTDpgrsdiori Ftootofiw Kiyto monomer CH,CHC(0}-j-OCH1CHlCl F1I Residual Materials Degradation A Mobeef M FTOHequivaleikt or `AJcobol Eqiwriene' derivedfront W vbaaneee (e.g. S-2teerehlomereoyMe) present ki theTeel Sutetanw(TS> fteetedi Thecumd r*wnteerite andknpurtMeidentifiedendpreeent h theTeal Subetance bout Velues XI weight percent(wtK) Fluorineh theTeel Sutetanee (TS) % X2-wehlperMnt(vd%)FluorTOhlteFkionitelonerAicoM (FTOH)RewMelerai usedto meketheTeel Subdance X3 weight percent(wt%) 6-2 Fluotouloniet Alcohol (S-2FTOH) Inthe FboraMomerAlcohol Rawl/blerial | e * 1T2nwstAEInWywsrperns BTTseSotwent SdSiwdAEtaXcMvsbpvngstTssiSuMaici AE Mas* Balance Approach Th. ma couTM. of raa/dj fluorotomw cob dagnuMon pttw ld a mudt m ot. , . o r V. to th . ..p a rtTM data man the corraapondng time course of polymer degradation. Kinetic Modeling Sum m ary * Primary source of PFCA frt* with a > 10,000 model for degradation of Residual 33 Materials alone. - s j nos l-UFTA `-s-rruA **1FTA --02FTUA 70FTA PFO 7-2iFTOH400 incaptiaol moBaol iJtiaol > 10,000 > 10,000 > 10.000 38 * Calculated degradation haH-lifa of 45 Residual Materials ranges between 16 and 45 days in the four soils. 16 * Calculated Acrylate Polymer degradation half-life is greater than 10,000 years. too 30* 400 On AmyWiPfimr Mid log i t i l -- Summary & Conclusions i .F(CFt)," CHCHCO,H 73uAcM -J, _i_ -'CO, Jj 4 4 4 OiJdrtoo I ------ ' [Monitored StudyAnatytes] *M FTO! 07fTA 0-2FTUA M FTA *-PFO 7-2FTOH' OO \ InessfekiMfWM Ortrtin t a k^r: Degradation analytes determined in th . teat system can be e xclu.iy.ty attnbuted to degradation of residual fluorotelomer raw materials and impurities in the test substance. The results obtained trom kinetic modeling the degradation kinetics o( the tluoroacrylate polymer further support the conclusion that PFO formation is dominantly due to t h . transformation of th . residual materials. The degradation of the polymeric structure appears to be negligible with calculated degradation half-lives that are > 10,000 years. 8-2 FluorMdomorAtohd (FTOH) F(CF1),CH,C>l,OH M FhicM staiw AM IFTA). F(CF,),CH,COCH M ftrtrrtsofnerlMscOifWsd AodIFTUAJ F(CT^CFOTCOOH M *"* Y-JrffTOH F(CF|)ICHKH3000H FICF^CmOHXX, PFO, PFN, PFD. PFU(PFCA*) F(CF,J,COOH. n ? t ( PFN, PFO and PFU levels observed are coneitent vdth expectations based on test sdrstence composition and (mown degradation pathways, (e.g. PFN -1% of PFO) PFN. PFD and PFU levels observed are consistent with expectations based on test substance composition and known degradation pathways, (e.g. PFN *1 % of PFO) Demonstrated analytical methods & study operation for over 15 months. ' 3 -W d . * S h fa. <11 1 w , ^ . fovTM, Se rw vw 36(2). S31. A. Wang 4 L p. 28 Do not cite or quote. Not for further distribution without author approval. Summary Study results to date Soil and Sludge methodologies and analytical methods have been demonstrated No evidence of polymer transformation observed - Inherent Biodegradation in Sludge - 28 Days - Biodegradation in four Soils - 180 Days Ongoing studies Soil Studies continuing to one-year Sediment studies commenced continuing to one year Anaerobic sludge studies to commence shortly