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AR226-2700 AR226-2700 TORONTO WORKSHOP MATERIALS September 13-14,2004 John Gannon DuPont Central Research & Develop Wilmington, DE of in the Is the Sources? contribution of emissions dj,rect is the potential for degradation of the Fluorotelomeras an indirect source? as an contribution of Fluorotelomer raw ma source? Potential PFCA Sources : F(CF2) ^'^y^fj' Particle size categories: Particle diameter (Dp): Dominant Removal Mechanism: Typical residence time: Coarse mode D > 2.5 urn Gravitational settling minutes to days Accumulation mode < 0.1 Lim < D < 2.5 Lim Wet deposition days to weeks Aitkens mo < 0.1 Dry dep minutes on soil/ in water via gravitational settling / 9 Materials that are volatile or sublime may evaporate back to atmosphe 8 The dominant particle sources (by mass) in air are mineral dust from w soils and sea-salt particles from wave-breaking. After Material deposited on soil and in water via wet deposition: 9 Water soluble/miscible materials will move with water (e.g., PFCAs) 8 Water insoluble materials with high adsorption coefficients may adso matrix at or near the surface (e.g.. fluorotelomer alcohols (FtOH)) 8 Note: TRP soil adsorption studies showed essentially full recovery of Ft soils and soil pore water, but no FtOH in air traps. Adsorption clearly Questions: Would FtOH adsorbed to wind-blown soils be: reactive in the atmosphere? in remote locations as wind-blown soil with adsorbe may: a account for transport of PFCAs and FtOH from surf to the atmosphere. a enhance rate of sublimation for PFCAs from soil sur m limit potential for FtOH transformation in atmosphe a deposit FtOH in remote locations as wind-blown soi adsorbed FtOH. 1. and may be deposited in marine bo of and with 2. and winds move sea-salts into at 3. PFCAs may enter atmosphere via transport on evaporate/sublime from marine boundar 4. FtOH enter atmosphere via transport on or perhaps it is transformed in marine b it may be to sediments. 7 p @ | EB OQ wn pi aine, Wha a y ul Egn er ei ==8 PnLn EELR A, = wok ZZzz o8= a adE n te e Leat eh ra La r 2"Rl bLi e aE ld Pa LhEoyy o 0 oZz SilenTl da ey iree! So be a Ei Lvbatsrs didKr| RI " ) g Luv; | EB = nn WL SAfo L be E 3 Rfr A mgi opt g FhLi ih SENFREE HE Bb ey ERE ALE i = m= See nh) Sl E IeehEi 3fl i ial 8g 8 ga BE Wo Ll kad oA ped S& 2g e Tnmba heod || =3 22B M SA Hh ad r Soc 3 | = 3 ) 8: | via in patterns affected by wind,, topography9 and earthy rot rasshopper Effect & Global Fractio fAcfS'e vol.attile s-i Bista ce-s: I-SSB iMlallia s.iudti'astamc.ieas. series of air-surface exchange events fol initial emission-deposition event. e of evaporationJsubllmation to the atmosphere, for a and then wet deposition (i.e., rain. snow or differing behaviors of chemicals as tran influence residence time and hop probability PFCA Sources : FCCF,) fttolllilllilli^ '^tellBiIBi^ f^^i|||i||||||i : ^lii^l^^iiSlftI^ ^^gl^tlll ' f1iyilr^|^l||ffi|^ l^^nuiaillii^ ^R^iD^iti^ rT=B-ti giil@^iiiiii^ ^.j^wea- ;':;'.; llrTipuri^ieiin t.^^POSF': .:;:: W ^^^^^^^ iiiiB's-zoiii ^^"^^i--l.^g^ ^^^^%^ Bl^^ To evaluate Fluorotelomer-based Pol (FTBP) as a potential contributor, we need to look at the potential for the FT be degraded. (FTI B %. Abiotic Transformation Hydrolysis Thermal (Incineration Studies) Photochemical Stability under Industrial & Con Use conditions Biodegradability: Sewage Treatment Pla . Modified Zahn-Wellens Test per OECD 302B . STP Simulation Test per OECD 303A Anaerobic Biodegradability of Organic Compounds Digested Sludge per OECD 311 (FT 9 Biodegradability: Soils and Sediments Aerobic and Anaerobic Biodegradation Studies . Range of soils and sediments to allow for evaluatio differences in physical-chemical parameters that m influence biodegradability potential. Expected Duration: 1 year m Determine Kinetics (if possible) fully answer questions about PFCA sources in environm understanding contributions of emissions from all PFC Need to develop a global distribution model to evaluate relationshi PFCA emissions with presence in environment and biota. Need to Understand if Fluorotelomer-based Polymers Transfor | oA EF EEN 3 Qu Ea Dg gl --= BN 5 ~ 5 -~~ |CEECS ol ) i1IV a .-- NU / ) p lo ~~ Hh _ i