ASTM F1308-98(2023)
(Test Method)Standard Test Method for Quantitating Volatile Extractables in Microwave Susceptors Used for Food Products
Standard Test Method for Quantitating Volatile Extractables in Microwave Susceptors Used for Food Products
SIGNIFICANCE AND USE
5.1 This test method is intended to measure volatile extractables that may be emitted from a microwave susceptor material during use. It may be a useful procedure to assist in minimizing the amount of volatile extractables either through susceptor design or manufacturing processes.
5.2 Modification of this procedure by utilizing appropriate qualitative GC detection such as a mass spectrometer in place of the flame ionization detector may provide identification of volatile extractables of unknown identity.
SCOPE
1.1 This test method covers complete microwave susceptors.
1.2 This test method covers a procedure for quantitating volatile compounds whose identity has been established and which are evolved when a microwave susceptor sample is tested under simulated use conditions.
1.3 This test method was collaboratively evaluated with a variety of volatile compounds (see statistical evaluation). For compounds other than those evaluated, the analyst should determine the sensitivity and reproducibility of the method by carrying out appropriate spike and recovery studies. The analyst is referred to Practice E260 for guidance.
1.4 For purposes of verifying the identity of or identifying unknown volatile compounds, the analyst is encouraged to incorporate techniques such as gas chromatography/mass spectroscopy, gas chromatography/infrared spectroscopy, or other techniques in conjunction with this test method.
1.5 A sensitivity level of approximately 0.025 μg/in.2 is achievable for the compounds studied in Table 1. Where other compounds are being quantitated and uncertainty exists over method sensitivity, the analyst is referred to Practice E260 for procedures on determining sensitivity of chromatographic methods.
1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific safety hazards warnings are given in 10.2, 11.1, and 11.6.
1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
General Information
- Status
- Published
- Publication Date
- 31-Mar-2023
- Technical Committee
- F02 - Primary Barrier Packaging
- Drafting Committee
- F02.15 - Chemical/Safety Properties
Relations
- Effective Date
- 01-Sep-2019
- Refers
ASTM F1317-98(2019) - Standard Test Method for Calibration of Microwave Ovens (Withdrawn 2024) - Effective Date
- 01-Mar-2019
- Effective Date
- 01-Nov-2012
- Effective Date
- 01-Nov-2011
- Effective Date
- 01-Apr-2007
- Effective Date
- 01-Mar-2006
- Effective Date
- 01-Jan-2001
- Effective Date
- 01-Jan-2001
- Effective Date
- 10-Oct-1998
Overview
ASTM F1308-98(2023) - Standard Test Method for Quantitating Volatile Extractables in Microwave Susceptors Used for Food Products establishes a detailed, reproducible procedure to measure and quantify volatile compounds released from microwave susceptors under conditions simulating their actual use with food products. Microwave susceptors are materials typically used in food packaging to enhance the heating efficiency when microwaved. Monitoring and minimizing the volatile extractables from these materials is critical for food safety, regulatory compliance, and quality assurance.
This standard is applicable to complete microwave susceptor assemblies and provides guidance for testing, calibration, and analytical methodologies, ensuring results that are reliable and transferable across laboratories. The test method aligns with internationally recognized principles as per WTO TBT Committee recommendations, supporting global harmonization in packaging material safety assessment.
Key Topics
Quantitation of Volatile Extractables
- Focuses on quantifying established volatile compounds that may be emitted during microwave use.
- Ensures the measurement of substances relevant to food safety and consumer protection.
Simulated Use Testing
- Recommends sample testing under conditions that replicate intended use in food heating, ensuring practical applicability of results.
Analytical Methodology
- Utilizes gas chromatography (GC), with guidance to incorporate detectors such as flame ionization (FID) or mass spectrometry (GC-MS) for identification and quantitation.
- Details calibration procedures with standard solutions, rigorous apparatus preparation, and quality control through control blanks.
Sensitivity and Reproducibility
- Establishes achievable sensitivity limits (e.g., approximately 0.025 μg/in² for evaluated compounds).
- Encourages verification through spike and recovery studies, referencing ASTM Practice E260 for chromatographic methods.
Material Guidelines
- Emphasizes using samples representative of the entire susceptor, stored under controlled humidity and temperature to ensure consistency.
Safety and Regulatory Considerations
- Advises users to determine and apply pertinent safety, health, and environmental practices, as well as regulatory limitations.
Applications
The ASTM F1308-98(2023) test method offers value across several domains:
Food Packaging Design and QA
- Enables manufacturers to evaluate and optimize susceptor design and materials to limit potentially harmful volatile emissions during microwave heating.
- Supports compliance with food safety standards and regulatory requirements.
Material and Supplier Qualification
- Provides a robust, standardized approach for vetting new materials or suppliers by quantifying volatile extractables released during realistic use scenarios.
Regulatory Submissions and Documentation
- Facilitates the generation of data for regulatory filings regarding the safety and suitability of food-contact microwave packaging materials.
Research and Development
- Offers a scientific basis for developing new susceptor technologies or alternative food packaging solutions focused on minimizing chemical emissions.
Interlaboratory Comparability
- The method’s standardization of conditions and analytical techniques ensures data comparability within the industry and among international partners.
Related Standards
The following standards and practices are referenced in ASTM F1308-98(2023) or are related to the quantitation of volatile extractables in packaging materials:
- ASTM E260 – Practice for Packed Column Gas Chromatography: Guidance for sensitivity and reproducibility studies in chromatographic quantitation.
- ASTM F1317 – Test Method for Calibration of Microwave Ovens: Essential for achieving standardized heating conditions in sample preparation.
- TAPPI T 402 – Standard Conditioning and Testing Atmospheres for Paper, Board, Pulp Handsheets, and Related Products: Defines protocols for controlling humidity and temperature during sample storage and testing.
- TAPPI TIS 808 – Equilibrium Relative Humidities over Saturated Salt Solutions: Guidance on achieving specified environmental conditions for test samples.
Summary
ASTM F1308-98(2023) is a critical standard for quantitating volatile extractable compounds in microwave susceptors designed for food packaging applications. By following this robust, internationally recognized method, manufacturers, laboratories, and regulatory bodies can ensure product safety, support material innovation, and maintain consumer trust in microwaveable packaged foods.
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Frequently Asked Questions
ASTM F1308-98(2023) is a standard published by ASTM International. Its full title is "Standard Test Method for Quantitating Volatile Extractables in Microwave Susceptors Used for Food Products". This standard covers: SIGNIFICANCE AND USE 5.1 This test method is intended to measure volatile extractables that may be emitted from a microwave susceptor material during use. It may be a useful procedure to assist in minimizing the amount of volatile extractables either through susceptor design or manufacturing processes. 5.2 Modification of this procedure by utilizing appropriate qualitative GC detection such as a mass spectrometer in place of the flame ionization detector may provide identification of volatile extractables of unknown identity. SCOPE 1.1 This test method covers complete microwave susceptors. 1.2 This test method covers a procedure for quantitating volatile compounds whose identity has been established and which are evolved when a microwave susceptor sample is tested under simulated use conditions. 1.3 This test method was collaboratively evaluated with a variety of volatile compounds (see statistical evaluation). For compounds other than those evaluated, the analyst should determine the sensitivity and reproducibility of the method by carrying out appropriate spike and recovery studies. The analyst is referred to Practice E260 for guidance. 1.4 For purposes of verifying the identity of or identifying unknown volatile compounds, the analyst is encouraged to incorporate techniques such as gas chromatography/mass spectroscopy, gas chromatography/infrared spectroscopy, or other techniques in conjunction with this test method. 1.5 A sensitivity level of approximately 0.025 μg/in.2 is achievable for the compounds studied in Table 1. Where other compounds are being quantitated and uncertainty exists over method sensitivity, the analyst is referred to Practice E260 for procedures on determining sensitivity of chromatographic methods. 1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific safety hazards warnings are given in 10.2, 11.1, and 11.6. 1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
SIGNIFICANCE AND USE 5.1 This test method is intended to measure volatile extractables that may be emitted from a microwave susceptor material during use. It may be a useful procedure to assist in minimizing the amount of volatile extractables either through susceptor design or manufacturing processes. 5.2 Modification of this procedure by utilizing appropriate qualitative GC detection such as a mass spectrometer in place of the flame ionization detector may provide identification of volatile extractables of unknown identity. SCOPE 1.1 This test method covers complete microwave susceptors. 1.2 This test method covers a procedure for quantitating volatile compounds whose identity has been established and which are evolved when a microwave susceptor sample is tested under simulated use conditions. 1.3 This test method was collaboratively evaluated with a variety of volatile compounds (see statistical evaluation). For compounds other than those evaluated, the analyst should determine the sensitivity and reproducibility of the method by carrying out appropriate spike and recovery studies. The analyst is referred to Practice E260 for guidance. 1.4 For purposes of verifying the identity of or identifying unknown volatile compounds, the analyst is encouraged to incorporate techniques such as gas chromatography/mass spectroscopy, gas chromatography/infrared spectroscopy, or other techniques in conjunction with this test method. 1.5 A sensitivity level of approximately 0.025 μg/in.2 is achievable for the compounds studied in Table 1. Where other compounds are being quantitated and uncertainty exists over method sensitivity, the analyst is referred to Practice E260 for procedures on determining sensitivity of chromatographic methods. 1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific safety hazards warnings are given in 10.2, 11.1, and 11.6. 1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
ASTM F1308-98(2023) is classified under the following ICS (International Classification for Standards) categories: 67.250 - Materials and articles in contact with foodstuffs. The ICS classification helps identify the subject area and facilitates finding related standards.
ASTM F1308-98(2023) has the following relationships with other standards: It is inter standard links to ASTM E260-96(2019), ASTM F1317-98(2019), ASTM F1317-98(2012), ASTM E260-96(2011), ASTM F1317-98(2007), ASTM E260-96(2006), ASTM E260-96, ASTM E260-96(2001), ASTM F1317-98(2002). Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
ASTM F1308-98(2023) is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: F1308 − 98 (Reapproved 2023)
Standard Test Method for
Quantitating Volatile Extractables in Microwave Susceptors
Used for Food Products
This standard is issued under the fixed designation F1308; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope mine the applicability of regulatory limitations prior to use.
Specific safety hazards warnings are given in 10.2, 11.1, and
1.1 This test method covers complete microwave suscep-
11.6.
tors.
1.8 This international standard was developed in accor-
1.2 This test method covers a procedure for quantitating
dance with internationally recognized principles on standard-
volatile compounds whose identity has been established and
ization established in the Decision on Principles for the
which are evolved when a microwave susceptor sample is
Development of International Standards, Guides and Recom-
tested under simulated use conditions.
mendations issued by the World Trade Organization Technical
1.3 This test method was collaboratively evaluated with a Barriers to Trade (TBT) Committee.
variety of volatile compounds (see statistical evaluation). For
2. Referenced Documents
compounds other than those evaluated, the analyst should
determine the sensitivity and reproducibility of the method by 2.1 ASTM Standards:
carrying out appropriate spike and recovery studies. The
E260 Practice for Packed Column Gas Chromatography
analyst is referred to Practice E260 for guidance. F1317 Test Method for Calibration of Microwave Ovens
2.2 TAPPI Standards:
1.4 For purposes of verifying the identity of or identifying
T 402 Standard conditioning and testing atmospheres for
unknown volatile compounds, the analyst is encouraged to
paper, board, pulp handsheets, and related products
incorporate techniques such as gas chromatography/mass
TIS 808 Equilibrium relative humidities over saturated salt
spectroscopy, gas chromatography/infrared spectroscopy, or
solutions
other techniques in conjunction with this test method.
1.5 A sensitivity level of approximately 0.025 μg/in. is
3. Terminology
achievable for the compounds studied in Table 1. Where other
3.1 Definitions:
compounds are being quantitated and uncertainty exists over
3.1.1 microwave susceptors, n—a packaging material
method sensitivity, the analyst is referred to Practice E260 for
which, when placed in a microwave field, interacts with the
procedures on determining sensitivity of chromatographic
field and provides heating for the products the package
methods.
contains.
1.6 The values stated in SI units are to be regarded as
3.1.2 volatile extractables, n—those chemical species which
standard. No other units of measurement are included in this
are released from the microwave susceptor and can be detected
standard.
in the headspace under conditions simulating those under
1.7 This standard does not purport to address all of the
which the susceptor is used. Extractability does not necessarily
safety concerns, if any, associated with its use. It is the
mean migration of the extractable species to the product being
responsibility of the user of this standard to establish appro-
heated on the susceptors.
priate safety, health, and environmental practices and deter-
4. Summary of Test Method
4.1 Volatile extractables are determined by subjecting a
This test method is under the jurisdiction of ASTM Committee F02 on Primary
Barrier Packaging and is the direct responsibility of Subcommittee F02.15 on sample of the susceptor material to microwave heating, fol-
Chemical/Safety Properties.
lowed by headspace sampling and gas chromatography. Quali-
Current edition approved April 1, 2023. Published April 2023. Originally
tative analysis may be carried out on a gas chromatograph
approved in 1990. Last previous edition approved in 2018 as F1308 – 98 (2018).
(GC) coupled to an appropriate detector capable of compound
DOI: 10.1520/F1308-98R23.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on Available from Technical Association of the Pulp and Paper Industry (TAPPI),
the ASTM website. 15 Technology Parkway South, Norcross, GA 30092, http://www.tappi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F1308 − 98 (2023)
TABLE 1 Analyte Recovery Without Microwaving
6.2 Apparatus—Because this test method is designed for
Within trace volatiles, and is highly sensitive, contaminants on vials,
Recovery Overall
A B
Compound ( n) Laboratory Note(s)
septa, syringes, etc. can lead to misinterpretation of results.
Mean, % Variability, %
Variability, %
Preparing apparatus properly and carrying out blank determi-
Benzene 5 97.7 7.8 9.0
nations as specified in the procedure is essential to minimize
2-Butoxy-ethanol 4 98.7 6.7 8.4 1
Dibutyl Ether 5 109.7 16.5 23.7
this possibility.
Dodecane 3 101.1 10.7 10.7 1, 2
2-Furfural 4 99.7 11.7 12.0 1
7. Apparatus and Reagents
Furan- 3 100.0 14.1 16.4 1, 3
2-Methanol
7.1 Microwave Oven—Calibrated, 700 6 35 W, no turn-
Isobutyl Alcohol 4 96.0 7.1 7.9 4
table. See Test Method F1317.
Methylene 5 103.5 16.7 22.6
Chloride
7.2 Humidity Chambers, operated at 50 % RH and 23 °C.
2-Propanol 3 99.9 11.4 12.0 4
7.2.1 Requirements for constant temperature-humidity
Styrene 5 100.8 8.5 9.3
Toluene 4 102.7 9.9 10.9 4 chambers and equilibrium relative humidities over saturated
Overall 101.1 11.6 14.4
salt solutions are outlined in TAPPI Methods T 402-om-88, and
A
n = number of laboratories submitting data on compound.
TIS 808-03.
B
Notes: Collaborating laboratories provided the following reasons for not sub-
mitting data on a particular analyte:
7.3 Vials, headspace, 20 mL (actual volume 21.5 mL). To
1. The analyst felt interaction was occurring among various analytes and spent
ensure against extraneous peaks in the gas chromatographic
several days investigating. The laboratory manager refused to allow additional
traces, wash vials thoroughly and dry in a 125 °C air oven for
time for collaborative study.
2. The analyst questioned the solubility of the analyte and did not add to the
a minimum of 4 h before using.
spike mixture.
7.4 Vial Crimp Caps.
3. A fresh standard was not prepared fresh daily. This compound degrades
measurably in water in 24 h.
7.5 Septa, Polytetrafluoroethylene (PTFE)/silicone. To en-
4. The analyst experienced coelution of peaks under conditions of collaborative
study on his/her particular system.
sure that the septa are free of volatiles, cover the bottom of a
15 cm petri dish with septa, PTFE-polymer side up. Micro-
wave at full power for 10 min. Place microwaved septa into a
vacuum (greater than 29 in.) oven at 130 °C for 16 h.
identification. Volatile extractables are quantitated by compari-
7.6 Crimping Tool for vials.
son with standards of known concentration.
7.7 Syringe, 2 mL, gas-tight with valve. Store syringe in
5. Significance and Use
90 °C oven between uses.
5.1 This test method is intended to measure volatile extract-
7.8 Gas Chromatograph equipped as follows:
ables that may be emitted from a microwave susceptor material
7.8.1 FID Detector, compatible with capillary columns.
during use. It may be a useful procedure to assist in minimizing
7.8.2 Injector, split/splitless compatible with capillary col-
the amount of volatile extractables either through susceptor
umns.
design or manufacturing processes.
7.8.3 Automated Headspace Sampler, Optional.
5.2 Modification of this procedure by utilizing appropriate
7.8.4 Column, DB-5, 30 m, 0.25 mm inside diameter, 1 μm
qualitative GC detection such as a mass spectrometer in place
film thickness, or 0.32 mm. (A short piece of deactivated
of the flame ionization detector may provide identification of
0.25 mm fused silica column may be placed between the
volatile extractables of unknown identity.
injector and the column to serve as a guard column.)
7.8.5 Peak-Area Integration System compatible with GC
6. Interferences
system. Alternatively, a chart recorder and hand integration can
6.1 Gas Chromatography—Because of the potentially large be used.
number of chemical species that can be analyzed using this
7.9 Fluoroptic Thermometry System .
methodology, not all species will be resolved from one another
7.10 Temperature Probes, high temperature.
on a particular GC column under a given set of conditions.
Techniques available to the analyst to verify the identity of the
7.11 Beaker, 600 mL.
species being quantitated include retention time comparisons
7.12 Oven, hot air, set for 90 °C.
using alternate GC conditions or using an alternate GC column
7.13 Stopwatch.
to verify identification. Good judgement of chromatographic
4,5,6
results is always important. Refer to Practice E260 for
7.14 4-Heptanone.
guidance.
7.15 Standard Solutions—Regular Method:
7.15.1 Internal Standard Solution (245 μg/mL
4-Heptanone)—To approximately 950 mL of distilled water in
McCown, S. M., and Radenheimer, P., “An Equilibrium Headspace Gas
Chromatographic Method for the Determination of Volatile Residues in Vegetable
Oils and Fats,” LC/GC, Vol 7, No. 11, 1989, pp. 918–924.
5 6
McNeal, T. P., and Breder, C. V., “Headspace Gas Chromatographic Determi- McNeal, T. P., and Breder, C. V., “Headspace Sampling and Gas-Solid
nation of Residual 1,3-Butadiene in Rubber-Modified Plastics and Its Migration Chromatographic Determination of Residual Acrylonitrile in Acrylonitrile Copoly-
from Plastic Containers Into Selected Foods,” Journal of the Association of mer Solutions,” Journal of the Association of Offıcial Analytical Chemists, Vol 64,
Analytical Chemists, Vol 70, No. 1, 1987, pp. 18–21. No. 2, 1981, pp. 270–275.
F1308 − 98 (2023)
a 1-L volumetric flask add 300 μL of 4-heptanone. Mix well 8.1.4 Place 250 mL of room-temperature distilled water into
and dilute to volume with water. a 600 mL beaker. Place the beaker in the center rear of the
microwave oven.
7.15.2 Standard Solution 1: (Prepare fresh daily.)—To ap-
2 2
8.1.5 Cut a 10 mm by 65 mm (6.5 cm = 1 in. ) portion
proximately 475 mL of internal standard solution in a 500 mL
volumetric flask, add 50 μL of each of the compounds to be from the susceptor sample to be tested. Insert carefully into the
20 mL headspace vial.
quantitated. Mix well, and dilute to volume with internal
standard solution. If difficulty is experienced with dissolution 8.1.6 Using a 13 gauge syringe needle, pierce a hole into a
of analyte, alternate standard solution procedure may over- headspace vial septum. Place the septum on the vial and crimp.
come this difficulty. 8.1.7 Insert one temperature probe (7.10) through the sep-
7.15.3 Standard Solution 2—Repeat 7.14.2 using 25 μL of tum hole into the vial and manipulate it until it is in contact
with the active face of the susceptor material. Place the vial on
each compound.
its side in the center of microwave oven, crimp end toward
7.15.4 Standard Solution 3—Repeat 7.14.2 using 10 μL of
right of the oven, and susceptor with active face up.
each compound.
8.1.8 Microwave at full power, recording the probe
7.16 Standard Solutions—Alternate Method:
temperature, preferably at 5 s intervals, but at intervals not to
7.16.1 Alternate Internal Standard Solution (1225 μg/mL
exceed 15 s.
4-Heptanone)—To approximately 150 mL of helium-sparged
8.1.9 Plot the temperatures from 8.1.3 and 8.1.8 on the same
orthodichlorobenzene (ODCB) in a 200 mL volumetric flask
graph.
add 300 μL of 4-heptanone. Mix well and dilute to volume with
8.1.10 Compare the plots. If the trace from 8.1.8 closely
ODCB.
approximates or is slightly higher than the plot from 8.1.3 then
7.16.2 Alternate Standard Solution 1— To approximately 75
the test time will be equal to the maximum product cook time
mL of alternate internal standard solution in a 100 mL volu-
of the product in that oven. If the trace is substantially higher
metric flask, add 50 μL of each of the compounds to be
or lower than that of the susceptor with product, then adjust the
quantitated. Mix well, and dilute to volume with alternate
mass or surface area, or both, (by changing container size) of
internal standard solution.
the water (using a fresh sample of room temperature distilled
7.16.3 Alternate Standard Solution 2— Repeat 7.15.2 using
water) as necessary to achieve a similar profile. Record the
25 μL of each compound.
mass of water and type of container that gives the best
7.16.4 Alternate Standard Solution 3— Repeat 7.15.2 using
agreement between the test sample and the product temperature
10 μL of each compound.
profiles.
7.17 Susceptor Blank—Obtain a repres
...




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