Document VJBgNj37pwL82JREgB9Qp3aZ

Society of Environmental Toxicology & Chemistry Summary of DuPont Presentations AR226-3352 SETAC Europe April 18-22, 2004 Prague, Czech Republic Perfluorooctyl Ethanol Biodegradation : Transformation Products and Pathway BuckR.C.1. Wang N.2, Folsom P.W.2, Szostek B.3, Capka V.^and Gannon J.T.2; 1 DuPont Chemical Solutions Enterprise, Wilmington, DE, USA2 DuPont Central Research and Development; USA 3 DuPont Haskell Laboratory, USA. The environmental fate of chemicals containing perfluorocarbon moieties [F(CPz)n-] is of increasing scientific and public interest. Carbon-fluorine bonds are extremely strong (116 kcai'mol'1). As a result, it is generally believed that perfluorocarbon chains do not readily biodegrade and carbon-carbon bond scission in the perfluorocarbon chain is not expected. We have investigated the biotransformation in microbial culture ofradiolabeled perfluorooctyl ethanol, F(CF2)7l4CF2CH2CH20H, commonly known as 8-2 Telomer B Alcohol, under a number of conditions and timeframes to elucidate the biotransformation pathway(s) and identify transformation products. The studies conducted, including major transformation products and proposed transformation pathway(s), will be discussed. The results demonstrate that the -CHzCHz- "spacer" influences the biotransformation pathway(s). Among many metabolites observed, F(CF2)7COOH is neither the major nor the final stable biotransformation product. Soil-Water Partitioning of a Fluorotelomer Intermediate used to Manufacture Fluorotelomer-based Polymers William R. Berti1. Robert C. Buck1, Hiroyuki Iwai2, Ning Wang1, Volker Koch3, Seiji Shinya4,Bogden Szostek1, Robert Waterland' - Telomer Research Program 'DuPont Co., ^aikin Industries, Ltd., Variant GmbH, "Asahi Glass Co., Ltd. Fluorotelomer intermediates are used to manufacture fluorotelomer-based polymer products, which provide unique properties to a wide variety of consumer products. Four telomer manufacturers that are collectively sponsoring research on telomer compounds jointly sponsor the Telomer Research Program (TRP). The TRP program includes investigations on the environmental fate and effects properties of fluorotelomer intermediates. A soil-water partitioning study using a batch equilibrium method is being conducted on the fluorotelomer intermediate 8-2 Telomer B Alcohol [8-2 TBA; CF3(CF2)7CH2CHzOH, CAS# 678-39-7]. Results of the study demonstrated that greater than 90% of ^C-labelled 8-2 TBA initially added to the test system partitioned to soil and sediment within three hours. The 8-2 TBA partitioned to activated sludge within one hour. Less than 2% remained in the aqueous phase at a 1:1 soihsolution ratio after 3 hours at 4C; total recovery of the compound was 95% and greater under these conditions. In one soil after 24 h equilibration time and at room temperature, 50% or more of the ^C label added as 8-2 TBA was bound to the residual fraction, which was determined by combusting the soil after three washings with acetone, air-drying, and grinding. We will summarize the soil-water partitioning studies that have been conducted on the 8-2 TBA, including adsorption and desorption isotherm data and the organic carbon partitioning coefficients (Koc) determined in the studies. We will also discuss progress in understanding partitioning/ condensation of 8-2 TBA in the vapor phase to solids. Physicochemical Properties of Fluorotelomer Alcohols Mary A. Kaiser. 1 Daryl P. Cobranchi,1 Chien-Ping Chai Kao,2 Paul J. Krusic,3 Alexander A. Marchione,3 and Robert C. Buck4 ' DuPont Corporate Center for Analytical Sciences, Central Research and Development, Experimental Station, Wilmington, DE 19880-0402,2 DuPont Corporate Center for Engineering Research, Central Research and Development, Experimental Station, Wilmington, DE 19880-0304,3 DuPont Corporate Center for Analytical Sciences, Experimental Station, Wilmington, DE 19880-0328,4 DuPont Chemical Solutions Enterprise, Barley Mill Plaza 23, Wilmington, DE 19805 Physicochemical properties such as vapor pressure and solubility are necessary to determine environmental transport potential and environmental fate. Often these properties are estimated from models based on properties of chemically similar materials. Fluorinated compounds, however, are especially difficult to model since the properties offluorinated compounds are quite different from their hydrocarbon analogues. Fluorotelomer alcohols are also difficult to obtain in pure form since they are "products by process" which are a mixture of several compounds each differing by two carbon units. setae dupont presentations tracking document.doc Page 4 of 12 Society of Environmental Toxicology & Chemistry Summary of DuPont Presentations This presentation describes three experiments used to measure vapor pressure of individual fluorotelomer alcohols, including a novel experiment using gas-phase nuclear magnetic resonance spectroscopy. The physicochemical properties of me fluorotelomer alcohols are compared to their hydrocarbon analogues to demonstrate their unusual properties. Effects of Fluorotelomer Products on the Bacterial Growth, Degradation of Organic substances, and Microcosmic Population from Activated Sludge of Domestic Sewage Treatment Plant WangN.1. Folsom P.W. \ Decarolis, J., Berti W.R.', Buck R.C.2, and Gannon, J.T.'. 1 DuPont Central Research and Development, Newark, DE, USA;2 DuPont Chemical Solutions Enterprise, Wilmington, DE, USA. Fluorotelomer-based materials are widely used in various consumer products. As part of environmental stewardship effort, we are investigating possible physiological impact offluorotelomer-based products such as Zonyl 8300, Zonyl FCC, Zonyl FSN and Zonyl FSP on the microcosm from activated sludge of domestic sewage treatment plant (POTW). The growth of bacteria at me presence of up to Ig TOCequivalent L"' of the fluorotelomer products in addition to 0.1% yeast extract was monitored by measuring the turbidity (absorbance at 600 nm) for 48 h at 30 C. The growth patterns of the bacteria were very similar at the presence or absence of the fluorotelomer products and none of the products showed any inhibitory effect on the bacterial growth at the highest product concentration (Ig TOC-equivalent L''). The ability of the activated sludge to degrade organic substances such as "C-labeled aniline at the presence of fluorotelomer products will be discussed. The results about the impact of the fluorotelomer products on the microcosmic population (monitored over time by denatured gradient gel electrophoresis) will also be presented. Application ofLC-MS/MS methodology to determination ofTelomer B alcohols, perfluorinated acids, and fluorosurfactants in environmental matrices. Bogdan Szostek1, Vladimir Capka*, Keith B. Prickett1, S. Mark Kenned/, Robert C. Buck2 1. DuPont Haskell Laboratory for Health and Environmental Sciences, Newark, DE 2. DuPont Chemical Solutions Enterprise, Wilmington, DE, USA A need for measurement of perfluorinated compounds in environmental matrices has increased significantly in recent years. Appropriate analytical methodology, sampling, sample preparation procedures, as well as applicable measurement techniques are being established by many researchers for this group of compounds. Unique physico chemical properties of these compounds require special consideration when analytical methods are established. Especially, a careful method validation demonstrating proper spike recoveries for the matrix of interest, "clean" blanks, and sample storage conditions are of the most importance. Our effort is focused around the development of analytical methodology for Telomer B alcohols, biodegradation products ofTelomer B alcohols, Telomer-derived fluorosurfactants, and polymers in environmental matrices to support environmental fate and effects studies with these materials. LC-MS/MS methodology is predominantly utilized for determination of perfluorinated acids. GC-MS methodology has been traditionally utilized for determination oftelomer B alcohols. There is a strong demand to be able to measure both of these types ofanalytes by a single technique. The presentation will discuss our efforts to measure both types ofanalytes by LC-MS/MS. Appropriate sample preparation, clean-up procedures, samples storage conditions, method validation data, achievable limit of detection, and analyte specific recommendations will be discussed. Additionally, challenges of analyzing complex mixtures of fluorosurfactants and applicable analytical methodology will be outlined. TELOMER RESEARCH PROGRAM Ecotoxicity Profile of lH,lH,2H,2H-Perfluorodecanol (C8-2 Telomer B Alcohol) Volker Koch1. William R Berti2, Robert C Buck2, John Gannon2, Robert A Hoke2, Hiroyuki Seiji Shinya4,Ning Wang2 - Telomer Research Program 'Clariant Germany, DuPont USA, ^aikin Japan, *Asbai Glass Japan Iwai3, Mary A Kaiser2, lH,lH,2H,2H-Perfluorodecanol, CAS No. 678-39-7 (C8-2 Telomer B Alcohol) is an important speciality intermediate. More than 80% of the produced amount oftelomer alcohols are used for the preparation of high setae dupont presentations tracking document.doc Page 5 of 12 Society of Environmental Toxicology & Chemistry Summary of DuPont Presentations molecular weight polyacrylate polymers containing perfluorinated alcohols. These so-called Telomer-based Polyacrylate Polymers (TBPPs) are used e.g. for the coating of textiles and carpets to achieve resistance against water, oil and stains. The producers oftelomer alcohols are currently investigating in detail the environmental fate and effects properties oftelomer alcohols and especially of lH,lH,2H,2H-Perfluorodecanol within the Telomer Research Program (TRP). Telomer alcohols have in comparison to their hydrogenated counterparts exceptional physico-chemical properties which are related to the fluorine atoms. But these properties (e.g. very low water solubility, high vapour pressure) are considerable challenges for ecotoxicity testing. Within TRP testing strategies for this substance which is difficult to test were developed based on state-of-the-art methodology. The poster will present basic physico-chemical properties of lH,lH,2H,2H-Perfluorodecanol, applied design for acute and chronic aquatic tests as well as terrestrial / sediment tests and the results for the different species tested. Evaluation of Environmental Exposure and Long-range Tranport Potential for Perfluorinated 8-2 Telomer B Alcohol Klasmeier J.. Matthies M.; University ofOsnabruck, Osnabrtick, Germany. Available substance data of perfluorinated 8-2 Telomer B Alcohol (8-2 TBA) have been evaluated and necessary input data for model calculations have been compiled. Data basis proved to be insufficient as some key parameters like KAW ^d Koc are highly uncertain. Assuming a realistic emission scenario for textile application [1] steady state concentrations have been estimated with SimpleBox multimedia model. More than 95% of total 8-2 TBA mass are calculated to reside in compartments air and agricultural soil. Steady state mass ratio between these two compartments proved to be strongly dependent on partitioning behavior expressed by KAW and Koc- For most combinations of these two parameters, mass fraction in air accounts to more than 60%. For sensitivity analyses probability distributions have been attributed to uncertain parameters and a Monte-Carlo analysis has been used to propagate these uncertainties through the model. Highest sensitivity is calculated for partition coefficients KAW and Koc affecting all compartments but air. Instead, air concentration is influenced by degradation rate in air, advective flow (wind speed) and respective emissions. Concentration in water is generally low and mostly dependent on emission assumptions. Characteristic travel distances (CTD) in air calculated with ELPOS multimedia model [2] is predominately determined by degradation in air, because deposition of the substance is considerably low. Ranking against a set of about 700 well-known environmental contaminants representing a wide variety of substance properties gave a rank coefficient of about 0.9 indicating a relatively high long range transport potential in air. Potential for condensation in cold regions is low. Average half-life in air is small (6 -16 days [3]) compared to the average exchange time between troposphere and lower stratosphere (15-18 months) indicating that 8-2 TBA will not constitute a similar stratospheric problem like fluorinated hydrocarbons. [1] Telomers Research Program, pers. communication, 2003. [2] Beyer A., Matthies M.; Criteria for atmospheric long-range transport potential and persistence of pesticides and industrial chemicals. UBA-report no. 8/02, E. Schmidt Verlag Berlin, 2002 [3] Ellis D.A., Martin J.W., Mabury S.A., Hurley M.D., Andersen M.P.S., Wallington T.J.; Environ. Sci. Technol. 37 (17), 3816-3820,2003. ATMOSPHERIC LIFETIMES AND DEGRADATION MECHANISMS OF FLUOROTELOMER ALCOHOLS CF3(CF2)nCH2CH20H Dr. Georges LeBras. CNRS-LCSR (Orleans, France) Perflurorooctane sulfonate (PFOS) detected in humans and animals is very likely produced from polyfluorinated sulfonamido-ethanols. For this reason PFOS and related compounds have been phased out. The fludrotelomers alcohols (FTOHs) are mainly used in analogous polymeric applications as the sulfonamido-ethanols and they are expected to be present in the atmospheric gas phase. In order to assess the environmental impact of FTOHs a kinetic and mechanistic study of the gas phase oxidation of such compounds by the OH radical has been carried out. The studied compounds are trifluoropropanol, CF3CH2CH20H (TFP) and tridecafluorooctanol, C6F13CH2CH20H (TDO). setae dupont presentations tracking document.doc Page 6 of 12 Society of Environmental Toxicology & Chemistry Summary of DuPont Presentations The rate constant measurements of the OH reaction with TFP and TDO has provided similar values. This indicates that the length of the perfluorinated chain has no influence on the reactivity of the alcohol. Therefore the same rate constant can be recommended for larger FTOHs, such as 2-perfluoro-n-octyl ethanol, C8F17CH2CH20H (2POE), which is of more industrial interest but difficult to investigate due to its low vapor pressure. The atmospheric lifetime of FTOHs deduced from the rate constant measurements is 1 Idays. The mechanistic study has been carded out in two photoreactors: a 150 L Teflon bag irradiated by lamps and the 200 m3 European photoreactor irradiated by sunlight in Valencia (Spain). For the OH-initiated oxidation of TFP in air the major primary products are the fluoroaldehydes CF3CH2CHO and CF3CHO, in the presence and absence of NOx, CF20 being the end product. This mechanism can be generalised for larger FTOHs, including TDO and 2POE. m this case the intermediate aldehydes will be CF3(CH2)nCH2CHO and CP3(CF2)nCHO. Based on the obtained data the amospheric fate of the FTOHs will be discussed. setae dupont presentations tracking document.doc Page 7 of 12