Document 6w1owL0eNvdMkpp8v7D0VDgEo

AR226-3342 Environmental fate studies o f fluorotelomer interm ediates used to produce surfactants and p o ifin e rs Bill Berti DuPont Central Research & Development Wilmington, Delaware USA Themiracles o f science Acknowledgements uNing Wang Daryl Cobranchi ^Barbara Larsen Bogden Szostek Mary Kaiser John Gannon Bob Buck Lisa Sulecki Pat Folsom Mark Starr Chien-Ping Kao Christopher Bowers Vladimir Capka (ffypoft Outline Background Intermediates and Products Overview of E-fate studies Physical-Chemical Properties Water solubility and Vapor Pressure . 6-2TBI, 8-2TBI, 6-2TBA, 8-2TBA Measured vs. Predicted Values f^ cf^ ch^ oh f(cf2cf2),,cHjCH2i n = 3 or 4 . E-Fate Testing: 8-2 TBA fccf.cf^ ch^ oh a Abiotic: Soil/Water Partitioning, Hydrolytic Stability Biotic: Biotranformations Conclusions DuPont Fluorotelomer Product Groups^ Intermediates, Surfactants, Polymers 1) Intermediates CF2=CF2 (TFE) 1 F(CF2CF2)nI (Telomer A) n = 2-8 F(CF2CF2)nCH2CH2i (Telomer B) Sales Products 2} Surfactants / "Mofecuies" Anionic - Phosphate, Carboxyiate, Sulfonate Nonionic Ethoxyiate Betaine F(CF2CF2)nCH2CH2()H (Telomer BA) Straight Chain Alkyl F(CF2CF2)nCH2CH20C(0)C(R)=CH2 Zonyl TM <r=ch,) ; Zonyl TAN (r=h) ^ / Acrylic Ester Amide Urethane :es. Environmental Fate Studies Goal: Identify environmental transformations relevant to toxicity and chemical cycling ^ -Physical-chemical properties Aqueous stability Photolysis S -Soil/water partitioning -Respiration inhibition (toxicity) yiAerobic transformations -Anaerobic transformations <iHI O u tlin e m 8. 39 Physical-Chemical Properties F(CF2CFE)nCH2CH2OH Water solubility and Vapor Pressure F(CF2CF * 6-2TBI, 8-2TBI, 6-2TBA, 8-2TBA n = 3 or 4 Measured vs. Predicted Values a FCCF2F2),^CHjCHjOH m & IS W a te r s o lu b ility : M e a s u re d v s , m o d e le d W A T E R N T vl.O O Based upon a "fragment constant" method os S a m e method as KOW W IN Program W S K O W v 1 .41 > Molecular Weight a Melting Point, for solids only and when available ' Measured WS WSKOW v1.41 1.E+06 WATERNT v1.00 WSKOW v1.41, MP _i 1 E+04 O) i * 1.E+02 m m m m m m m m m m sssm ! 'm i <10 Ok0T). 1.E+00 |3 1.E-02 * I' .: 1.E-04 6-2TBI 8-2TBI 6-2TBA 8-2TBA 1B- Vapor Pressure; Measured vs. modeled .......................................... .................. ....... Measured VP Gas saturation 1000 - Measured VP MPBPWIN V1.4-S m pbpw in vi.4i. bp & mp method M P B P W IN v 1 .41 * Vapor pressure oo CM @ a 100 a. m * Boiling point (at 760 mm Hg) * Melting point 3 W a. 10 a. > 1 ---- ---- 1----_ j----- -H 6-2TBI 8-2TBI 6-2TBA 8-2TBA (il 5 Modeling for Physical/Chemical Properties - Summary________ m Demonstrate applicability of existing models for this class of compounds * Vapor pressure predictions are reliable on limited set of data (4 compounds) W ater solubility measurements vs. predictions need more study * Examine other models PQJ? m <3$Aa V :uUUU\> & lJV 0 fV 1 6 W Q i c .'-!0 i0 SlUOi0v> - 39 - , S' i< FCF2CF2),,H2CH2OH F{CF2Fa),,CHjCH2I 5? = 3 or 4 E-Fate Testing: 8-2 TBA fccf^ f^ ch^ oh Abiotic: Soil/Water Partitioning, Hydrolytic Stability Biotic: Biotranformations Soil/W ater Partitioning Studies^ fP^dilF^dalF ^C31HI "250" Two materials Keyport silt loam . Sand 17%, Silt 62%, Clay 21%, pH 5.3, OM 4.0% 15 min 4 6 hours W hite Clay Creek sand . Sand 98%, Silt 2%, pH 7.2, OM 0.4% Mix for 15 m and 46 h, separate phases 4 Extracted with hexane from solid and water phases, SPE to clean, analyzed Keyport WhiteClay Control Mean Std dev Soil/Water Partitioning Studies; Summary m At 15 m Good recovery (>90% of expected) of 8-2 TBA from both soils R ecovered primarily from solid phase, except for < 4 % in solution of W hite Clay Poor recovery from control with no soil Recovered from both solution and tube At 46 h 3 Poor recovery from both soils . W hite Clay <25% of expected Keyport <75% of expected ss Improved recovery from control with no soil 62% vs. 45% after 15 m * Losses due to volatilization, extraction inefficiencies, ___ transformations??? CQ'OP0MI> Aqueous Stability; F(F2CF2) 4CH2CH2OH Hydrolytic reactions are one of the most common means of non-biological degradation of substances in the environm ent 300 5 150 pg 8-2TBA L*1, sterile conditions pH 4, 7, 9 @ 50C pH 1.2 @ 37C rao. < CHO CM Sealed glass vials with Alfoil liners 4 replicates at 0 and 5 days Extracted with MTBE Analyzed with GC/MS Difference % pH 1.2, 37C -6.7 pH 4, 50C 8.7 Day 0 UDay 5 pH 7, 50C 9.6 pH 9, 50C -3.8 Aqueous Stabilitys Summary 8-2 TBA is hydrolytically (abiotically) stable <10% change in concentration after 5 days compared to day 0 Accelerated Biodegradations F ( C F 2C F 2) 4C H 2C H 2O H 8 Objective: Determine if 8-2 TBA undergoes biotransformations 8 Experimental method: Modified OECD 302D with 0.1% yeast extract ss Innoculum: Industrial WWTP; adapted with 50 mg/L 8-2 TBA is Experimental System: Sealed bottles, "cold" test substance Experimental Duration: 0 to 28 days at room temperature a O. 1000 O o 800 o m 600 o o |-- 200 <N 00 70 * 8-2 TBA + Fresh Sludge O 8-2 TBA + K illed Sludge 2 mM NaCf> , , *, 60 50 } I ?. , A i a" U. 30 20 10 - O o Q. o S 10 15 20 25 Days after the initiation 30 U "Ready" Aerobic Biodegradation; F(CF2CF2) 4CH2CH2OH Growth medium: OECD 301D mineral medium without yeast extract Inoculum source: Municipal PO TW , non-adapted Term inated early due to problem s w ith killed c o n tro ls "Ready Biodegradation" of 8-2 TBA iiodegradation Studies^ Summary Quick transformation in accelerated studies Transformation products include e F(CF2CF2)4CH2COOH . F(CF2)7CF=CHCOOH Mass balance <50% :s O th e r p ro d u c ts /lo s s e s ? ? ? m On-going studies to understand killed controls and incomplete recoveries E-Fate Testing Plans for Surfactants, Polymers 1) Intermediates CF2=CF2 (TFE) l Telomer A Telomer BI Telomer BA Zonyl TM (i= C H ), Zonyl TAN <R=H) Sales Products Surfactants * Anionic 1 Sulfonate * NonionicCEthoxyiate) * Betaine Hvdrolvtic Stability 31 Polymers J ^ A c r y lij *j Ready Bindearadabilitv OECD 30 IB -C 02 production Measurement F- endpoints Parent compound Products UjrethaneJ Conclusions m Measured vs. model values Telomer BA and BI High confidence in vapor pressure measurements and model estimates a Low(er) confidence in water solubility estimates Need to assess alternative models 8-2 TBA a Hydrolytically stable Soil/water partitioning studies may indicate strong adsorption to soils Accelerated biodegradation studies show production of transformation products Volatilization is of concern * N eed to develop and validate analytical methods in air ___ JPiD?