ASTM D6003-96

Standard Test Method for Determining Weight Loss From Plastic Materials Exposed to Simulated Municipal Solid-Waste (MSW) Aerobic Compost Environment (Withdrawn 2005)

SCOPE
1.1 This test method is used to determine the degree and rate of aerobic biodegradation of plastic materials exposed to a controlled composting environment. Aerobic composting takes place in an environment where temperature, aeration, and humidity are closely monitored and controlled.  
1.2 The test is designed to determine the biodegradability of plastic materials, relative to that of a standard material, in an aerobic environment. Aeration of the test reactors is maintained at a constant rate throughout the test and reactor vessels of a size no greater than 4-L volume are used to ensure that the temperature of the vessels is approximately the same as that of the controlled environment chamber.  
1.3 Biodegradability of the plastic is assessed by determining the amount of weight loss from samples exposed to a biologically active compost relative to the weight loss from samples exposed to a "poisoned" control.  
1.4 The test is designed to be applicable to all plastic materials that are not inhibitory to the bacteria and fungi present in the simulated Municipal Solid Waste (MSW).  
1.5 The values stated in SI units are to be regarded as the standard.  
1.6 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 and health practices and determine the applicability of regulatory limitations prior to use.  
Note 1- There is no similar or equivalent ISO standard.
WITHDRAWN RATIONALE
This test method was used to determine the degree and rate of aerobic biodegradation of plastic materials exposed to a controlled composting environment. Aerobic composting takes place in an environment where temperature, aeration, and humidity are closely monitored and controlled.
Formerly under the jurisdiction of Committee D20 on Plastics, this test method was withdrawn in December 2004 in accordance with section 10.5.3.1 of the Regulations Governing ASTM Technical Committees, which requires that standards shall be updated by the end of the eighth year since the last approval date.

General Information

• Status: Withdrawn
• Publication Date: 31-Dec-1995
• Withdrawal Date: 19-Apr-2005
• ICS: 13.030.10 - Solid wastes
• ICS: 83.040.01 - Raw materials for rubber and plastics in general
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.96 - Environmentally Degradable Plastics and Biobased Products

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn. Contact ASTM
International (www.astm.org) for the latest information.
Designation:D6003–96
Standard Test Method for
Determining Weight Loss From Plastic Materials Exposed to
Simulated Municipal Solid-Waste (MSW) Aerobic Compost
Environment
This standard is issued under the fixed designation D6003; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope D1898 Practice for Sampling of Plastics
D2973 Test Method for Total Nitrogen in Peat Materials
1.1 Thistestmethodisusedtodeterminethedegreeandrate
D2974 Test Methods for Moisture,Ash, and Organic Mat-
of aerobic biodegradation of plastic materials exposed to a
ter of Peat and Other Organic Soils
controlledcompostingenvironment.Aerobiccompostingtakes
D2976 Test Method for pH of Peat Materials
place in an environment where temperature, aeration, and
D2980 Test Method for Volume Weights, Water-Holding
humidity are closely monitored and controlled.
Capacity, andAir Capacity of Water-Saturated Peat Mate-
1.2 Thetestisdesignedtodeterminethebiodegradabilityof
rials
plastic materials, relative to that of a standard material, in an
D3593 Molecular Weight Averages and Molecular Weight
aerobicenvironment.Aerationofthetestreactorsismaintained
DistributionofCertainPolymersbyLiquidSizeExclusion
at a constant rate throughout the test and reactor vessels of a
Chromatography (Gel Permeation Chromatography)
size no greater than 4-L volume are used to ensure that the
D4129 TestMethodforTotalandOrganicCarboninWater
temperature of the vessels is approximately the same as that of
by High-Temperature Oxidation and Coulometric Detec-
the controlled environment chamber.
tion
1.3 Biodegradability of the plastic is assessed by determin-
D5338 Test Method for Determining Aerobic Biodegrada-
ing the amount of weight loss from samples exposed to a
tion of Plastic Materials under Controlled Composting
biologically active compost relative to the weight loss from
Conditions
samples exposed to a “poisoned” control.
D5509 Practice for Exposing Plastics to a Simulated Com-
1.4 The test is designed to be applicable to all plastic
post Environment
materials that are not inhibitory to the bacteria and fungi
D5512 Practice for Exposing Plastics to a Simulated Com-
present in the simulated Municipal Solid Waste (MSW).
post Environment Using an Externally Heated Reactor
1.5 The values stated in SI units are to be regarded as the
2.2 APHA-AWWA-WPCF Standards:
standard.
2540 G Total, Fixed, and Volatile Solids in Solid and
1.6 This standard does not purport to address all of the
Semi-Solid Samples
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
3. Terminology
priate safety and health practices and determine the applica-
3.1 Definitions—Definitions of terms applying to this test
bility of regulatory limitations prior to use.
method appear in Terminology D883 and Practice D5509.
NOTE 1—There is no similar or equivalent ISO method.
4. Summary of Test Method
2. Referenced Documents
4.1 The test method consists of the following:
2.1 ASTM Standards:
4.1.1 Selectingplasticmaterialsforexposureinacontrolled
D618 Practice for Conditioning of Plastics and Electrical
aerobic composting environment;
Insulating Materials for Testing
4.1.2 Preparing and characterizing a simulated compost
D883 Terminology Relating to Plastics
withtheproperC:Nratio,pH,waterholdingcapacity,porosity,
D1193 Specification for Reagent Water
and inoculum to establish and maintain a high biological
activity;
ThistestmethodisunderthejurisdictionofASTMCommitteeD-20onPlastics
and is the direct responsibility of Subcommittee D20.96 on Environmentally
Degradable Plastics. Annual Book of ASTM Standards, Vol 04.08.
Current edition approved Aug. 10, 1996. Published February 1997. Discontinued, 1993. Replaced by Test Method D5296.
2 6
Annual Book of ASTM Standards, Vol 08.01. Annual Book of ASTM Standards, Vol 11.02.
3 7
Annual Book of ASTM Standards, Vol 11.01. Annual Book of ASTM Standards, Vol 08.03.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn. Contact ASTM
International (www.astm.org) for the latest information.
D6003–96
4.1.3 Exposing the test materials to the compost under
controlled, aerobic conditions;
4.1.4 Removing the test specimens for cleaning; and
4.1.5 Assessing the degradability of the plastics by measur-
ing weight loss from the test specimens.
5. Significance and Use
5.1 Aerobic composting represents an attractive alternative
to the disposal of solid wastes in landfills. Composting by
biologically mediated oxidative decomposition produces
highly stable organic matter that may be used for land
applications or horticulture. However, the degradation of
plastics within a compost can affect the decomposition of
materialsenclosedbytheplastic,othernon-plasticmaterialsin
the compost, and the resulting composition and appearance of
NOTE 1—Bioreactor=acrylic cylinder; 127-mm (ID) 3300 mm long.
the composted material.This test is intended to help assess the
Air exit port=6.4 mm diameter.
environmental degradability of plastics under standard com-
Air inlet port=6.4 mm diameter; 25 mm above the acrylic bulkhead.
posting conditions. Characterization of the ability of a plastic
Perforated distribution plate: positioned 50 mm above the acrylic bulk-
to degrade under controlled, environmentally relevant condi-
head.
tionsisessentialwhendevelopingproductswithaprogrammed
FIG. 1 Schematic Drawing of the Aerobic Bioreactor
lifetime.
5.2 Considering the diversity of materials that may be
introduced into a particular compost, as well as the variety of
6.1.2 The bioreactors are connected to a filtered air supply
designs of composting facilities, it is important to recognize
capable of providing water-saturated air at a rate of 100 to 200
−1
that no single test can adequately simulate all the conditions
mL min . The air supply to each bioreactor is humidified by
which may occur during composting. Consequently, this test is
passing through a fritted-glass air dispersion tube immersed in
intended to provide a uniform, standardized environment
distilled water (300 mL in a 500-mL Erlenmeyer flask) and
simulating a representative MSW compost operating at near-
regulated via a flow meter (see Fig. 2).Water in the humidifier
optimum conditions.
flaskmustbemaintainedatthetemperatureoftheenvironment
5.3 Because a specimen degrades to the point where it can
chamber.
not be distinguished from the other materials within the
6.1.3 A controlled-environment chamber capable of main-
compost does not mean that it has become fully mineralized.
taining a temperature of 30 (62) to 70 (62) °C.
Determination of a plastic’s degradation products and their
6.2 Analytical Equipment:
potential toxicity requires further testing. Mineralization of the
6.2.1 Analytical Balance, to weigh test materials, (60.1
plastic material (that is, conversion of polymer-C to CO )
2 mg).
should be investigated using Test Method D5338.
6.2.2 Top Loading Balance, to weigh MSW samples for
5.4 Predicting long-term environmental fate and effects of a
determining water content, (60.01 g).
plastic from the results of short-term exposure to a simulated
wastedisposalenvironmentisdifficult.Thus,cautionshouldbe
exercised when extrapolating the results obtained from this or
anyothercontrolled-environmenttesttodisposalinthenatural
environment.
6. Apparatus
6.1 Composting Apparatus:
6.1.1 A suitable bioreactor vessel (see Fig. 1) consists of a
127-mm (i.d.) by 300-mm long acrylic cylinder; two acrylic
bulkhead plates (150 mm 3150 mm); two acrylic distribution
plates, positioned 25 mm from the bulkhead plates; and four
all-thread bolts with wing nuts. Air enters the bioreactor
through an inlet (6.4-mm i.d.) positioned about 25 mm above
thebottombulkhead,andexitsthebioreactorthroughanoutlet
(6.4-mm i.d.) in the top bulkhead.
NOTE 2—The size of the reactor may be changed as long as there is
sufficient volume to allow for the even distribution of the MSW and test
materials. However, the internal volume of the reaction vessel should not
exceed 4 L; this will allow adequate control of the internal temperature of
the compost via the exchange of heat between the contents of the reaction
vessel and the environment chamber. FIG. 2 Schematic of the Film Weight-Loss Bioreactor System
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn. Contact ASTM
International (www.astm.org) for the latest information.
D6003–96
TABLE 2 Mix 3 (2)
6.2.3 Oven, for determining the water content of the simu-
lated MSW compost, set at 103 to 105°C. Weight Carbon Nitrogen Water
Component
(g) (g) (g) (g)
6.2.4 Muffle Furnace,fordeterminingthevolatilesolidsand
Water 214.1 . . 214.1
ash content of the simulated MSW compost, set to 550 (650)
Sand 107.0 . . .
°C.
Rabbit chow (Purina HF 5326) 72.1 30.9 1.7 7.2
A
6.2.5 pH Meter.
Newspaper 53.6 24.9 0.1 4.8
Manure composted cow 5.4 2.2 0.1 .
Total 452.2 58.0 1.9 226.1
7. Reagents and Materials
A
Shredded; ca. 2 mm 3 25 mm.
7.1 All chemicals shall be of American Chemical Society
(ACS) reagent-grade quality.
7.2 Distilled water should be prepared in accordance with
8.2 The MSW may contain sharp objects; thus, to avoid
Specification D1193.
injury, extreme care should be taken when handling such
7.3 Simulated Municipal Solid Waste (MSW) Compost—
mixtures.
Simulated MSW composts range from the relatively simple to
8.3 The bioreactor vessel is not designed to withstand high
thecomplex;themixeslistedinTables1and2providesuitable
pressures; it should be operated at close to ambient pressure.
environments for this test.
7.3.1 Mix 2 (1) —940 g shredded leaves (1:1, w/w, mix of
9. Inoculum
oak and maple); 340 g shredded paper (1:1, w/w, mix of
9.1 Suitable inocula include:
newspaper and computer paper); 140 g mixed, frozen veg-
9.1.1 Commercial compost seed (for example, Recycle
etables; 120 g meat waste (added as a 1:1, w/w, mix of dried
Compost Makert, Ringer Corp., Minneapolis, MN).
dog food and dried cat food); 360 g dehydrated cow manure;
9.1.2 Material from a commercial composting process, or
40 g sawdust; 40 g urea; and 20 g commercial compost seed.
previous composting exposure.
Enough water is added to bring the mix to 60% water holding
9.1.3 Composted potting soil from a garden supply store or
capacity (Test Method D2980). The C:N ratio of the starting
a horizon material from a native soil.
mix is 14:1.
7.3.2 Mix4(3)—3500 g dehydrated alfalfa meal; 1300 g
10. Test Specimen
cottonseed meal; 1400 g Poplar sawdust; 1000 g fresh cow
10.1 Test specimens should conform to Practice D618.
manure;1500gblackgardensoil;2500gshreddednewspaper;
10.1.1 Plastic materials may be tested in the form of films
480 g CaCO ; 40 g NaHCO ; and 13 L of water. The mix is
3 3
(25 mm 375 mm) prepared by casting from solution or by
blendedinaHobartMixeruntiltheaverageparticlesizeis3to
melt forming (compression molding or extrusion).
4 mm. The C:N ratio of the starting mix is 30:1.
10.1.2 Fabricated parts, or sections cut from fabricated
7.3.3 An alternative MSW compost, designed to simulate a
parts, may also be used as test specimen.
particular waste stream, may be used.
7.4 A simulated yard-waste mix composed of dried grass
NOTE 3—Test and control specimens should have essentially the same
and leaves (67%, w/w) and twigs (33%, w/w) may be used in dimensions. An important factor in the choice of specimen configuration
istheratioofsurfaceareatointernalvolume.Specimensofthesametype
place of the MSW. The ratio of grass (typically rich in
ofmaterialbutwithdifferentdimensionsmayproducepercentweightloss
nitrogen) to leaves (typically low in nitrogen) should be
values (not normalized to the surface area) that differ significantly. It may
adjusted to provide a C:N ratio of about 25:1.
be necessary to test a range of forms and sizes to determine how this
affects the extent or rate of biodegradation.
8. Hazards
10.2 The test should include both degradable and nonde-
8.1 This test method requires the use of hazardous chemi-
gradable reference materials to follow the activity of the
cals. Avoid contact with chemicals and follow manufacturer’s
compost and standardize between-run testing.
instructions and Material Safety Data Sheets.
10.2.1 Suitable positive reference materials include: un-
coatedcellophaneandcelluloseacetatewithanaveragedegree
of substitution of less than or equal to two acetate esters per
The boldface numbers in parentheses refer to a list of references at the end of
glucose monomer.
this test method.
10.2.2 High-density polyethylene that has not been exposed
A
totoxicmaterials(forexample,theHDPEusedtomakeplastic
TABLE 1 Mix 1
milk bottles) is suitable as the negative reference material.
Wet Weight
Category Wet Weight of Specific Component (%)
(%)
NOTE 4—In devising a test program to determine quantitative changes
Food waste 16.6 Tomatoes (3.3), Lettuce (3.3), Meat (3.3),
occurring during and after composting, it is essential that the number of
Cottage Cheese (3.3), Bread (3.4)
replicate specimen be sufficient to establish a reliable value for the
Garden waste 13.9 Leaves (6.9), Grass (7.0)
propertyinquestion.Forahomogeneousmaterial,threetestspecimenper
Paper 58.5 Bleached (19.5), Brown (19.5), Cardboard
sampling point are usually adequate for assessing the visual effects of
(19.5)
exposure or for determining weight-loss; however, five replicate speci-
Plastics 7.7 Test material plus HDPE from shredded
plastic milk bottles mens are usually required for assessing changes in tensile-properties.
Textiles 0.8 Cotton
Always sample and test the same number of specimens for each exposure
Wood 2.5 Twigs
interval. It is to be expected that the physical properties of the specimens
A
See Practice D 5509. will vary as a function of exposure in the compost environment; hence
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn. Contact ASTM
International (www.astm.org) for the latest information.
D6003–96
values indicating the greatest amount of biodegradation are the most cantly different extents, the test should be repeated with the replicate
significant. ASTM Manual STP 15D may be used as a guide. specimen placed in specific locations (top, middle, or bottom) and with
specific orie
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