Post on 25-Jun-2015
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Exposure Assessment and Risk Characterization of Certain Fluoroorganic Chemicals Used in
Food Packaging
Stephen Korzeniowski, Robert C. Buck, Hsu-nan Huang, and Mary Kaiser
3rd International Symposium onFood Packaging
Ensuring the Safety, Quality and Traceability of Foods
17-19 November 2004Barcelona, Spain
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Poster Abstract
• The results of an exposure assessment and risk characterization study are reported for consumer paper food packaging articles manufactured with DuPont products. The goal was to develop a more in depth understanding of the magnitude of potential exposure to certain fluoroorganics that may occur through consumer use of commercial paper packaging.
• An additional goal was to develop a risk characterization based on Margins of Exposure (MOE's) approach. Results from a variety of tested articles will be presented showing MOE's of all > 30,000. Paper packaging was one of the articles tested in this study.
• Extraction studies were performed on paper packaging using a variety of solvents including water and ethanol and various cooking oils. Results from these studies as well as a review of the analytical challenges and significant method development efforts will be provided.
• The implications of this body of work and path forward will also be discussed.
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CF2=CF2 (TFE)
F(CF2CF2)nI (Telomer A)
F(CF2CF2)nCH2CH2I (Telomer B)
F(CF2CF2)nCH2CH2OH (Telomer BA)Straight Chain Alkyl
Sales Products
F(CF2CF2)nCH2CH2OC(O)C(R)=CH2
Zonyl® TM (R=CH3) ; Zonyl® TAN (R=H)
n = 2-8
Surfactants• Anionic - Phosphate, Carboxylate, Sulfonate
• Nonionic - Ethoxylate• Betaine
Polymers• Acrylic• Ester• Amide• Urethane• Urea
Raw Materials
5 Test Compounds
Represent Majority Product Line
DuPont Fluorotelomer Product Groups: Intermediates, Surfactants, Polymers
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How do they Work ?
• The fluorotelomer
functionality is
attached to a
functional
backbone which
adheres to the
substrate surface.
• The fluorocarbon
chain orients
perpendicular to
the surface, at the
air interface.
• CFCF33 Groups give Groups give veryvery low surface tension low surface tension
• Oil, grease and water repellent surfaceOil, grease and water repellent surface
CFCF33
|(CF2)n
|(CH2)2
|
Paper Substrate
CFCF33
|(CF2)n
|(CH2)2
|
CFCF33
|(CF2)n
|(CH2)2
|
CFCF33
|(CF2)n
|(CH2)2
|Backbone
bulk paper properties are unaffected
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Risk CharacterizationRisk is a function of Hazard and Exposure
• Hazard Assessment– Determine potential hazard(s) from toxicity testing linked to routes of
exposure
• Exposure Assessment– Routes of Exposure : Oral, Dermal, Inhalation– Determine how people come in contact with our products, how much & how
often
Risk = f (Exposure, Hazard)
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Environmental Fate & Effects
• Physical / chemical properties• Environmental compartments• Fate (abiotic & biotic)• Effects : aquatic, terrestrial
Exposure
• Product Trails, Mass Balance• Human & Environmental
Exposure Assessment• Risk Characterization
Toxicology
• Acute & Chronic Studies
• Oral, Dermal, Inhalation
• Pharmacokinetics
Human HealthRisk Assessment
Environmental
Risk Assessment
Analytical • Product & Substrate Analysis• Method Development and
Validation• Chemical “Standards”• External Labs
Academic Collaboration
Communication• Publications• Presentations
DuPontChemicalSolutionsEnterprise
dProduct Stewardship
Business Process
Science-Based Product Stewardship Approach
Manufacturing Technology
• Process Improvements• Facilities Re-engineering• Emissions Reduction
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Product StewardshipThrough the Entire “Life-Cycle”
DuPontManufacturing
IndustrialProcessing
Professional Use/Installation
ConsumerUse
Disposal
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Scope of the Exposure Assessment and Risk Characterization: Consumer Article Study
DuPontManufacturing
IndustrialProcessing
Professional Use/Installation
ConsumerUse
Disposal
Focus of the Assessment:• Direct use of the article;• Home fabrication using the article;• Incidental exposure to the article;• Care and maintenance of the article; and,• Foreseeable misuse of the article.
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Exposure Assessment and Risk Characterization Work Process
ConceptualizeExposure
QuantifyExposure
Develop RiskCharacterization
Conduct Peer Review
IssueFinal Report
DevelopHazard
Assessment
AnalyticalData
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Articles Included in the Assessment
Quantitative Evaluation of:
• Medical garments
• Carpeting
• Carpet care products
• Textiles (Apparel)
• Thread sealant tape
• Cookware
• Membranes (Apparel)
• Food Contact Paper
Quantitative Evaluation (Ingredients-basis) of:
• Stone, tile and wood sealants
• Industrial floor waxes and wax removers
• Latex paint
• Home and office cleaning products
• Textiles (Upholstery)
• Textiles (Home)
• Textiles (Technical)
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Food-Contact Paper Types
• Linerboards
• Folding Cartons
• Bags
• Flexible Packaging
• Support Cards
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Food-Contact Paper : Conceptual Exposures
• Exposure Pathways Quantified
– Dermal Contact
– Ingestion via Hand-to-Mouth
– Ingestion of Food
• Exposure Pathway dealt with as Uncertainty
– Paper Mouthing
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Food Exposure Factors: Examples
Dermal• Mass Available for transfer ng/cm2
• Fraction Transferred • Skin Surface Area• Dermal Absorption Coefficient• Exposure Time to Perspiration• Exposure Frequency (events/day)
Hand-to-Mouth• Mass Available for transfer ng/cm2
• Fraction Transferred• # Contact Events• Saliva Transfer Factor• Oral Absorption factor
Ingestion of Food• Mass Available for Transfer• Fraction Transferred• Contact Area: Paper-Food• Food Consumption Rate• Fraction of Consumed Food in
Contact with paper• Exposure Frequency/Duration• Oral Absorption Factor
Vapor Inhalation• Various Rates and Exposure
Factors - Time, Frequency, Duration
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Risk CharacterizationMargins of Exposure
Applicable Health Benchmark
Estimated Human ExposureMOE =
•Ratios of estimated human exposure levels to relevant health benchmarks
•Calculated separately for each article, each endpoint, and each receptor
•Aggregate MOE calculated to consider multiple-article exposure
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Overall Results and Conclusions
• Based on the exposure assessment and risk
characterization:
– Margins of exposure (MOEs, or “safety ratio) for all articles tested
ranged from 30,000 to 9 billion for Reasonable Maximum Exposure
scenarios (highly conservative)
– DuPont paper and packaging products had MOEs all >100,000
• The study reaffirms that our products are safe for their
intended uses
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Analytical Development and Characterization of Fluoroorganic Species in Food Packaging
• Develop a representative recovery analytical procedure for perfluorooctanoic acid (PFOA) in various oil matrixes– goal to develop method suitable primarily for microwave
packaging testing
• Construct a sensitive, specific and rugged analytical method for quantifying PFOA or its methyl ester (PFOME)
• Perform recovery analyses of PFOA/PFOME in fractionated coconut oil (MIGLYOL), silicone oils, corn oil, and olive oil– at room temperature and at 232oC for 5 minutes
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Recovery Analytical Procedure
• Spike a 1g oil sample with known concentrations of PFOA in acetone
• For room temperature recovery skip to next step, for 232oC recovery heat sample vials in an oven to temperature for 5 minutes
• Add 1mL of methanolic HCl to esterify PFOA to PFOME. Heat to 60oC for 30 minutes
• Extract organic layer and analyze via GC/MS.
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Analytical Detection Procedure
• Quantify the extracted PFOME by gas chromatography / mass spectrometry (GC/MS) technique
• Acquire heightened sensitivity through the use of chemical ionization, negative mode (NCI)
• Selectivity is produced by the selected ion monitoring (SIM) option
• Quantify analyte with external standard calibration
• Draft analytical method has a demonstrated limit of detection (LOD) of 1 ppb and a limit of quantitation of 5 ppb
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Equipment and Supplies: Oil Studies
Agilent GC 6890N US10206015Agilent MSD 5973Network US10482241Agilent Autosampler/Injector 7683 US20414158
CN14523138Edwards vacuum pump G1099-80023Agilent Enhanced ChemStation Version D.00.00.38DB-1ms 30m X 0.25mm X 0.25µm capillary columnUltra High Purity helium carrier gas MG IndustriesUltra High Purity methane reagent gas MG IndustriesMettler AE 163 analytical balance 86796
Acetone EM Science HR-GC AX0110-1Hydrogen Chloride, Methanol Reagent 10
TCI America X0041Methyl perfluorooctanoate, Oakwood Products, Inc. (98%) 002278 lot # T19LAcetonitrile, EMD Chromo. grade AX0142-1Hexanes, EM Science Chromo. grade HX0298-6MILLI-Q water
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Representative External Standard Calibration Curve
y = 44.472x + 36.653
R2 = 0.9994
0
1000
2000
3000
4000
5000
6000
0 20 40 60 80 100 120 140
conc. (ppb)
are
a
PFOME Standards range from 1.2 ppb to 120 ppb.
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PFOME Recovery Results: Oil Matrices
Test Oil T 0CPFOA Spike Range (ppb)
PFOME % Recovery
MIGLYOL 20-22 10-100 73-117
232 10-200 0-49
Silicone Oil (PS) 20-22 100 12-13
232 100 8
Silicone Oil (AA) 20-22 10-100 0
232 ND ND
Corn Oil 20-22 500-1500 3-5
232 50-200 0.5-1
Olive Oil 20-22 50-150 8-12
232 50-150 4-40All controls were non-detect ND is not determinedLOD = 1 ppb; LOQ = 5 ppb
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PFOA Oil Recovery Result Summary
• MIGLYOL room temperature experiment produced acceptable recoveries between 70% to 120%
• MIGLYOL at 232oC for 5 minutes experiment produced significantly lower recoveries between 0% to 49%
• Both Silicone Oils tested at room temperature and elevated temperature produced negligible recoveries
• Corn oil at room temperature yield 3-5% recoveries and at 232oC yield even lower (0.5-1%) recoveries
• Olive oil at room temperature yield 8-12% recoveries and 0-40% recoveries at elevated temperature
Conclusion• Use of the oils tested to conduct paper and packaging extraction analyses for
PFOA is unlikely to provide a meaningful result due to unacceptably low recoveries– It appears that the PFOA is reacting with the subject oils and therefore preventing appropriate
recovery
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Food Simulant Extraction Studies
• Ethanol solutions explored as food simulants for paper extraction studies to determine potential PFOA levels in paper and packaging
• Tested both 10% and 50% Ethanol solutions• Although not as desirable, determine if these
simulants can be used as a surrogate for oil extractants/simulants
• Other analytes were also considered in this study
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PFOA Analyses in Paper:Ethanol Simulants
• LC/MS/MS for sensitivity and selectivity• Require 5x signal to background at LOQ
– Minimize sample contact with fluoropolymers• HPLC parts and tubing• Autosampler vial caps
• 13C-PFOA dual isotopic internal standard corrects for matrix effects
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Paper Sample
Subsample #11 gram
Subsample #21 gram
Extract 2 Hrs
Centrifuge
Vial #1 Vial #2 Spike
Extract 2 Hrs
Centrifuge
Vial #1 Vial #2 Spike
Shaker Sample Preparation
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Experimental Conditions• Sciex API 4000 (Multiple Reaction Monitoring Mode)
– PFOA (413 to 369 m/z)– Dual 13C PFOA IS (415 to 370 m/z)
• HPLC Agilent 1100– Genesis C8 Column (2.1 mm x 50 mm, 4 um particle 120 Angstom)– Mobile Phase A: 2 mMolar ammonium acetate in nanopure H2O– Mobile Phase B: Methanol– 10 uL Injection Volume– Isocratic at 65% solvent B– PFOA Peak Elution 1.0 minute
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PFOA Calibration Curve 50% EtOH
PFOA Standard
Concentration (ng/mL)
13-C-PFOA Internal Standard
Concentration (ng/mL)
Average PFOA Area Response
(413 > 369 transition)
Average 13C-PFOA Internal Standard Area
Response (415 > 370 transition)
0.1 5.00 75093. 2781000. 0.5 5.00 322430. 2745900. 1.0 5.00 629740. 2794800. 5.0 5.00 2854000. 2707400.
20.0 5.00 5366700. 2545000.
Area Ratio vs Analyte Concentration (PFOA)- "Linear" Regression ("1 / x" weighting): y = 0.21 x + 0.00761 (r = 1.0000)
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20Analyte Concentration, ng/mL
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.3
Are
a R
atio
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Example Chromatogram (LLOQ Standard)
Sample Name: "Calibration 0.1 PPB" Sample ID: "" File: "Data072804 Covance 50%004.wiff"Peak Name: "PFOA" Mass(es): "412.9/368.9 amu"Comment: "" Annotation: ""
Sample Index: 1 Sample Type: Standard Concentration: 0.1000 ng/mL Calculated Conc: 0.1268 ng/mL Acq. Date: 07/28/2004 Acq. Time: 08:52:47 AM Modified: Yes RT Window: 30.0 secExpected RT: 1.09 minUse Relative RT: No Int. Type: Manual Retention Time: 1.08 minArea: 70143. countsHeight: 9029.7 cpsStart Time: 0.824 minEnd Time: 1.28 min
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0Time, min
0.00
200.00
400.00
600.00
800.00
1000.00
1200.00
1400.00
1600.00
1800.00
2000.00
2200.00
2400.00
2600.00
2800.00
3000.00
3200.00
3400.00
3600.00
3800.00
4000.00
4200.00
4400.00
4600.00
4800.00
5000.00
5200.00
5400.00
5600.00
5800.00
6000.00
6200.00
6400.00
6600.00
6800.00
7000.00
7200.00
7400.00
7600.00
7800.00
8000.00
8200.00
8400.00
8600.00
8800.00
9000.00
9200.00
9400.00
9600.00
9800.00
1.00e4
1.02e4
1.04e4
1.06e4
Intensity, cps
Sample Name: "Calibration 0.1 PPB" Sample ID: "" File: "Data072804 Covance 50%004.wiff"Peak Name: "DUAL 13C PFOA(IS)" Mass(es): "414.9/369.9 amu"Comment: "" Annotation: ""
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0Time, min
0.0
5000.0
1.0e4
1.5e4
2.0e4
2.5e4
3.0e4
3.5e4
4.0e4
4.5e4
5.0e4
5.5e4
6.0e4
6.5e4
7.0e4
7.5e4
8.0e4
8.5e4
9.0e4
9.5e4
1.0e5
1.1e5
1.1e5
1.2e5
1.2e5
1.3e5
1.3e5
1.4e5
1.4e5
1.5e5
1.5e5
1.6e5
1.6e5
1.7e5
1.7e5
1.8e5
1.8e5
1.9e5
1.9e5
2.0e5
2.0e5
2.1e5
2.1e5
2.2e5
2.2e5
2.3e5
2.3e5
2.4e5
2.4e5
2.5e5
2.5e5
2.6e5
2.6e5
2.7e5
2.7e5
2.8e5
2.8e5
2.9e5
2.9e5
3.0e5
3.0e5
3.1e5
3.1e5
3.2e5
3.2e5
3.3e5
3.3e5
3.4e5
3.4e5
3.5e5
3.5e5
3.6e5
3.6e5
3.7e5
Intensity, cps
1.07
0.1 ng/mL PFOA 5.0 ng/mL 13C-PFOA IS
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PFOA Method Validation in Paper Simulants
Extraction Solvent
Fortification0.5x
Fortification1x
Fortification2x
Fortification % Recovery 106 ± 9 106 ± 7 105 ± 4IS Response % 82 ± 7 86 ± 10 82 ± 8Fortification % Recovery 101 ± 5 103 ± 5 102 ± 3IS Response % 88 ± 6 87 ± 9 94 ± 2
Avg. ± St. Dev. (n=9)
10% Ethanol
50% Ethanol
Three treated paper samples fortified in triplicate at each level
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Food Simulant Extraction Studies
• Ethanol solutions explored as food simulants for paper extraction studies
• Tested both 10% and 50% Ethanol solutions
Conclusion• Methods have been developed to readily use
ethanol/water mixtures as food simulants for the determination of PFOA in food packaging
• An LOQ of 100 ppt and an LOD of 10 ppt were established in these matrices
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Sources
Sewer
Air
wwtpAgric. Soil
SurfaceWater
FreshwaterSediment
Sea
Estuary & Marine Sediment
Natur. SoilGrassland
Landfill
Incineration
FocusAreas
Environmental Compartments Under Study
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E-Fate Studies Approach
Raw Materials Products
Abiotic
• Photolysis - Air• Photolysis - Water• Hydrolysis• Partitioning• Adsorption-Desorption (Kd)• Aging / Sequestration
• Hydrolytic Stability• Incineration• Photolysis
Biotic• Sludge : Aerobic• Soil : Aerobic, Anaerobic
• Respiration Inhibition• Sludge: Aerobic• Soil : Aerobic, Anaerobic• Sediment : Anaerobic
Studies are underway. Biotic results are expected during the 1Q-4Q 2005 time period
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Acknowledgments
• Mike Mawn• Miguel Botelho• Barbara Larsen• Rhea Holtzman