Exposure Assessment and Risk Characterization of Certain Fluoroorganic Chemicals Used in Food Packag

1
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 on Food
Packaging Ensuring the Safety, Quality and
Traceability of Foods 17-19 November
2004 Barcelona, 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.

3
DuPont Fluorotelomer Product Groups
Intermediates, Surfactants, Polymers
Sales Products
Raw Materials
CF2CF2 (TFE)

• Surfactants
• Anionic - Phosphate, Carboxylate, Sulfonate
• Nonionic - Ethoxylate
• Betaine

F(CF2CF2)nI (Telomer A)
n 2-8

• Polymers
• Acrylic
• Ester
• Amide
• Urethane
• Urea

F(CF2CF2)nCH2CH2I (Telomer B)
F(CF2CF2)nCH2CH2OH (Telomer BA)
Straight Chain Alkyl
5 Test Compounds Represent Majority Product Line
F(CF2CF2)nCH2CH2OC(O)C(R)CH2 Zonyl TM (RCH3)
Zonyl TAN (RH)
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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.

• CF3 Groups give very low surface tension
• Oil, grease and water repellent surface

5
Risk Characterization

• Risk 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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Science-Based Product Stewardship Approach

• Toxicology
• Acute Chronic Studies
• Oral, Dermal, Inhalation
• Pharmacokinetics

• Analytical
• Product Substrate Analysis
• Method Development and Validation
• Chemical Standards
• External Labs

• Communication
• Publications
• Presentations

Human Health Risk Assessment
Academic Collaboration

• Exposure
• Product Trails, Mass Balance
• Human Environmental
• Exposure Assessment
• Risk Characterization

• Environmental Fate Effects
• Physical / chemical properties
• Environmental compartments
• Fate (abiotic biotic)
• Effects aquatic, terrestrial

Environmental Risk Assessment

• Manufacturing Technology
• Process Improvements
• Facilities Re-engineering
• Emissions Reduction

7
Product StewardshipThrough the Entire
Life-Cycle
DuPont Manufacturing
Industrial Processing
Professional Use/Installation
Consumer Use
Disposal
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Scope of the Exposure Assessment and Risk
Characterization Consumer Article Study
DuPont Manufacturing
Industrial Processing
Professional Use/Installation
Consumer Use
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
Quantify Exposure
Develop Risk Characterization
Develop Hazard Assessment
Conceptualize Exposure
Analytical Data
Conduct Peer Review
Issue Final Report
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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)

11
Food-Contact Paper Types

• Linerboards
• Folding Cartons
• Bags
• Flexible Packaging
• Support Cards

12
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

13
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

• 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 US10206015 Agilent MSD
5973Network US10482241 Agilent
Autosampler/Injector 7683 US20414158 CN1452
3138 Edwards vacuum pump G1099-80023 Agilent
Enhanced ChemStation Version D.00.00.38 DB-1ms
30m X 0.25mm X 0.25µm capillary column Ultra
High Purity helium carrier gas MG
Industries Ultra High Purity methane reagent
gas MG Industries Mettler AE 163 analytical
balance 86796 Acetone EM Science
HR-GC AX0110-1 Hydrogen Chloride, Methanol
Reagent 10 TCI America X0041 Methyl
perfluorooctanoate, Oakwood Products, Inc. (98)
002278 lot T19L Acetonitrile, EMD Chromo.
grade AX0142-1 Hexanes, EM Science Chromo.
grade HX0298-6 MILLI-Q water
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Representative External Standard Calibration Curve
PFOME Standards range from 1.2 ppb to 120 ppb.
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PFOME Recovery Results Oil Matrices
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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 PaperEthanol 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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Shaker Sample Preparation
Paper Sample
Subsample 1 1 gram
Subsample 2 1 gram
Extract 2 Hrs
Extract 2 Hrs
Centrifuge
Centrifuge
Vial 1
Vial 2
Spike
Vial 1
Vial 2
Spike
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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
13
PFOA
13
-
C
-
PFOA
Average PFOA Area
Average
C
-
PFOA
Standard

Internal Standard

Response

Internal Standard Area
Concentration
Concentration
(413 369 transition)

Response

(ng/mL)

(ng/mL)

(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.


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Example Chromatogram (LLOQ Standard)
0.1 ng/mL PFOA 5.0 ng/mL 13C-PFOA IS
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PFOA Method Validation in Paper Simulants
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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Environmental Compartments Under Study
Focus Areas
Air
Natur. Soil
Sources
wwtp
Grassland
Agric. Soil
Surface Water
Sea
Sewer
Freshwater Sediment
Landfill
Estuary Marine Sediment
Incineration
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E-Fate Studies Approach
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