Download determination on whether a substance is a hazardous substance

DETERMINATION ON WHETHER A SUBSTANCE IS A HAZARDOUS
SUBSTANCE PURSUANT TO SECTION 26 OF THE HSNO ACT
Application Code
HAZ03001
Application Type
Section 26 – determine whether a substance is hazardous
under the HSNO Act.
Applicant
Plastics New Zealand (Inc)
Date Application Received
2 April 2003
To be considered by
The Hazardous Substances Standing Committee of the
Authority.
Purpose of the Application
To determine whether or not certain fluoropolymers are
hazardous
Noel McCardle
Applications Advisor (Operations
Group)
Scientific Advisor (Science &
Analysis Group)
Tania van Maanen
Introduction
Fluoropolymers are a class of polymers analogous to polyolefins in which some or all of the
hydrogen atoms have been replaced by fluorine (and possibly other halides). Fluoropolymers (the
most well-known of which is poly(tetrafluoroethylene) [PTFE] or Teflon®), are extremely inert
with excellent thermal and chemical resistance and exceptional anti-frictional qualities. These
properties are exploited in applications such as non-stick cookware, ball bearings, piping, gaskets,
containers that need to be chemically resistant, and human organ prostheses.
No polymer manufacture is currently undertaken in New Zealand. Plastics are imported into the
country in the form of granules from which a range of products are manufactured. Manufactured
articles are exempt from the HSNO approval process but polymer granules fall within the HSNO
definition of a substance and as such, a HSNO approval is required if any of the HSNO hazardous
property thresholds are exceeded.
Substance Definition
For the purposes of this section 26 determination, fluoropolymers are defined as a class of
polymers analogous to polyolefins in which some or all of the hydrogen atoms have been
replaced by fluorine (and possibly other halides). Further, the definition is limited to those
fluoropolymers (not containing additives) with a number average molecular weight greater than
10 000 amu and with residual monomer, catalyst and solvent impurities present at levels less than
0.1%. In addition, polymers that are cationic (or potentially cationic) or those that are water
absorbing, are specifically excluded from this definition.
ERMA New Zealand section 26 determination HAZ03001
Page 1 of 19
Examples of fluoropolymers are listed in the application form HS7, provided as Appendix 1 to
this document.
Hazardous Property Assessment
An assessment of fluoropolymers against the HSNO thresholds was provided in the application
form (attached as Appendix 1 to this document). It is noted that often limited or no information
was available on these types of substances for a number of endpoints, especially data on
fluoropolymers as a group. Where information was available on specific fluoropolymers, this has
been provided.
However, it is recognised that this s26 determination is limited to fluoropolymers of very high
molecular weight (i.e. greater than10 000 amu) and as discussed in the application form, such
substances are not likely to be bioavailable and therefore highly unlikely to adversely affect either
human health or the environment.
A summary of the hazardous property assessment is provided below.
Class / Sub-class
Detail
Threshold
Class 1 – Explosiveness
Fluoropolymers are not considered explosive. They
do not meet the HSNO criteria for an explosive
substance and are not listed in the UN
Recommendations on the Transport of Dangerous
Goods.
Not triggered
Class 2,3,4 – Flammability
Fluoropolymers are not considered flammable. They
do not meet the HSNO criteria for a flammable
substance and are not listed in the UN
Recommendations on the Transport of Dangerous
Goods.
Not triggered
Sub-class 5.1 – Oxidisers
Fluoropolymers do not meet the HSNO
definition/criteria for an oxidising substance.
Not triggered
Subclass 5.2 – Organic
peroxides
Fluoropolymers do not meet the HSNO
definition/criteria for an organic peroxide.
Not triggered
Sub-class 6.1 – Acute toxicity
Fluoropolymers are not considered to be acutely
toxic as defined by the HSNO criteria. Rats fed
PTFE at a level of 12500 mg/kg showed no toxic
effects. The oral LD50 of the terpolymer (vinylidene
fluoride-haxafluoropropylene-tetrafluorethylene) was
greater than 40000 mg/kg. Rats fed the vinylidene
fluoride-haxafluoropropylene copolymer at 12500
mg/kg showed no clinical or nutritional signs of
toxicity.
Not triggered
ERMA New Zealand section 26 determination HAZ03001
Page 2 of 19
Class / Sub-class
Detail
Sub-class 6.3 – Skin irritancy
Fluoropolymers are not considered to be skin irritants Not triggered
as defined by the HSNO criteria. Skin irritation tests
with PTFE did not produce skin irritation. Polyvinyl
fluoride tested negative for skin irritation. Skin
irritation tests on the terpolymer (vinylidene fluoridehaxafluoropropylene-tetrafluorethylene) and the
copolymer vinylidene fluoride-haxafluoropropylene
produced only mild and transient responses,
insufficient to trigger HSNO thresholds.
Sub-class 6.4 – Eye irritancy
Fluoropolymers are not considered to be eye irritants
as defined by the HSNO criteria. Eye irritation tests
on the terpolymer (vinylidene fluoridehaxafluoropropylene-tetrafluorethylene) and the
copolymer vinylidene fluoride-haxafluoropropylene
produced only mild and transient responses,
insufficient to trigger HSNO thresholds.
Not triggered
Sub-class 6.5A – Respiratory
sensitisation
No information was located to indicate that
fluoropolymers would be respiratory sensitisers as
defined by the HSNO criteria.
Not triggered
Sub-class 6.5B – Contact
sensitisation
No information was located to indicate that
Not triggered
fluoropolymers would be contact sensitisers as
defined by the HSNO criteria. PTFE has not been
found to act as an allergenic agent. Polyvinyl fluoride
tested negative for skin sensitization.
Sub-class 6.6 – Mutagenicity
No information was located to indicate that
fluoropolymers would be mutagenic as defined by
the HSNO criteria.
Not triggered
Sub-class 6.7 –
Carcinogenicity
No information was located to indicate that
fluoropolymers would be carcinogenic as defined by
the HSNO criteria. The International Agency for
Research on Cancer (IARC) has classified PTFE as a
class 3 substance [unclassifiable as to carcinogenicity
to humans] i.e. not unclassifiable as a carcinogen
under HSNO.
Not triggered
Sub-class 6.8 – Reproductive
/ developmental effects
No information was located to indicate that
fluoropolymers would be reproductive
/developmental toxicants as defined by the HSNO
criteria.
Not triggered
ERMA New Zealand section 26 determination HAZ03001
Threshold
Page 3 of 19
Class / Sub-class
Detail
Threshold
Sub-class 6.9 – Target organ
systemic effects
No information was located to indicate that
fluoropolymers would be target organ systemic
toxicants as defined by the HSNO criteria. A 90 day
feeding study of rats with PTFE at levels up to 12500
mg/kg bw/day showed no signs of toxicity. A 10
month oral PTFE feeding study in rats showed no
effect on the animals.
Not triggered
Class 8 – Corrosivity
Fluoropolymers are not considered to be corrosive to
metals (sub-class 8.1), to skin (sub-class 8.2) or to
the eye (sub-class 8.3). Fluoropolymers are not
listed in the UN Recommendations on the Transport
of Dangerous Goods.
Not triggered
Class 9 - Ecotoxicity
Fluoropolymers are not considered to be ecotoxic
due to their low reactivity and high molecular
weight. As such, they will not be bioavailable and
therefore highly unlikely to adversely affect aquatic
life (sub-class 9.1), soil organisms (sub-class 9.2)
terrestrial vertebrates (subclass 9.3) or terrestrial
invertebrates (sub-class 9.4). Although
Fluoropolymers may not be rapidly biodegradable,
they will not bioaccumulate due to their low
bioavailablitiy.
Not triggered
Other information
As discussed in the application form (attached as Appendix 1 to this document), fluoropolymers
of molecular weight > 1,000 meet the USEPA polymer exemption rule and the NICNAS
polymers of low concern criteria. Furthermore, various fluoropolymers are permitted by the US
Food and Drug Administration (USFDA) “as articles or components of articles intended for use
in contact with food” e.g. CFR Title 21 paragraphs 177.1380, 177.1550, 177.2510.
ERMA New Zealand section 26 determination HAZ03001
Page 4 of 19
Recommended Determination
If the Authority is of the view that fluoropolymers are not hazardous under the HSNO
Act, then the Authority may:
a) determine that fluoropolymers as defined are not hazardous pursuant to section 26 of
the HSNO Act 1996; and
b) direct the Chief Executive to arrange for notice of this determination to be placed in
the Gazette.
Dr Donald Hannah, Manager, Science and Analysis
Date: 10 July 2003
Determination by the Authority
The recommended determination is approved.
Mr Tony Haggerty
Chair Hazardous Substances Standing Committee
Date: 30 July 2003
ERMA New Zealand section 26 determination HAZ03001
Page 5 of 19
Appendix 1
Application form HAZ03001 (attached)
ERMA New Zealand section 26 determination HAZ03001
Page 6 of 19
ER-AH-O7-1 07/2001
FORM HS7
Application for applying for a
determination under section 26 of the
Hazardous Substances and New Organisms Act 1996
Use this form for making an application for the Authority to make a formal
determination under Section 26 of the HSNO Act on whether or not a
substance is hazardous.
1.
Name and postal address of the organisation making the application:
Name: Plastics New Zealand
Address: P.O. Box 76378, Manukau City
Phone: 09 262 3773
Fax: 09 262 3850
2.
Name of the contact person for the application:
Name: Joanna Wojnar
Position: Scientific Advisor
Address: P.O. Box 131, Wellington
Phone: 04 918 4812
Fax: 04 914 0433
Email: [email protected]
Page 8 of 19
Fluoropolymers Mw > 10,000 amu
1
Definition
A family of polymers analogous to polyolefins in which some or all of the hydrogen
atoms attached to the carbon chain are replaced by fluorine (and possibly other
halides). Residual monomer, catalyst and solvent impurities <0.1%.
Substances include:
CAS
number
Structural formula
CF 2 CF 2
n
900284-0
CH 2
CH
F
CF 2 CF
n
CF 2 CF 2
CF 3
m
n
Names
Poly(tetrafluoroethylene)
(PTFE), Teflon®,
tetrafluoroethene
homopolymer, Gore-tex®,
perfluoroethylene polymer
2498114-4
Polyvinyl fluoride
2506711-2
Hexafluoropropene polymer
with tetrafluoroethylene
2493779-9
Polyvinylidene fluoride
900283-9
Poly(chlorotrifluoroethylene)
2510145-5
Ethylenechlorotrifluoroethylene
copolymer
901117-0
Vinylidene fluoridehaxafluoropropylene
copolymer
F
CH 2 C
F
F
n
F
C C
F
Cl n
F
CH 2 CH 2
F
n
F
C C
F
Cl m
F
F
C C
CH 2 C
F
CF 3
n
F
m
Page 9 of 19
2
Chemical and physical properties
Appearance: White-greyish, translucent solid.
Density: Varies, can range from 1.7 – 2.3 g cm-3 depending on monomer and
branching.
Melting point: Due to a range of molecular weights present in the polymer, melting
points are actually broad ranges. Values can range from 170 - 340ºC depending on
material.
Solubility in water: Insoluble in water.
3
Introduction
Fluoropolymers (the most famous one being poly(tetrafluoroethylene) or Teflon®) are
characterised by good thermal and chemical resistance and non-adhesiveness. This is
due to two factors: the fluorine/carbon bond is amongst the strongest known in organic
compounds and the fluorine atoms repel other atoms and molecules. The combination
of these two properties makes fluoropolymers extremely inert, unreactive, stable
towards solvents and other chemicals, and very slippery1. These properties are
exploited in applications such as non-stick cookware, ball bearings, piping, gaskets,
containers that need to be chemically resistant, and also in human organ prostheses.
4
Hazard Classifications
Class 1: Explosiveness – not triggered
The fluoropolymers are not explosive as they pass the ‘screening procedures for
substances which may have explosive properties’ as laid out in the User Guide to
HSNO thresholds and classifications2 and they are not listed in the UN
Recommendations on the Transport of Dangerous Goods3.
Class 2: Flammable gases and aerosols – not applicable
The fluoropolymers are solids.
Class 3: Liquids and liquid desensitised explosives – not applicable
The fluoropolymers are solids. They are not explosive.
Class 4: Flammability – not triggered
4.1.1 – readily
combustible
In general, fluoropolymers are non-flammable1. They
are also not listed in the UN Recommendations on the
Transport of Dangerous Goods3.
Page 10 of 19
4.1.2 – self-reactive
The fluoropolymers are not self-reactive as they pass
the ‘screening procedures for substances which may be
self-reactive substances’ as laid out in the User Guide
to HSNO thresholds and classifications2 and they are
not listed in the UN Recommendations on the Transport
of Dangerous Goods3.
4.1.3 – solid
desensitised
explosive
Not applicable – fluoropolymers are not explosive
4.2 –
spontaneously
combustible
The fluoropolymers are not spontaneously combustible
as they pass the ‘screening procedures for substances
which may be liable to spontaneous combustion’ as laid
out in the User Guide to HSNO thresholds and
classifications2 and they are not listed in the UN
Recommendations on the Transport of Dangerous
Goods3.
4.3 – dangerous
when wet
The fluoropolymers are not dangerous when wet as
they pass the ‘screening procedures for substances
which in contact with water may react to emit
flammable gases’ as laid out in the User Guide to
HSNO thresholds and classifications2 and they are not
listed in the UN Recommendations on the Transport of
Dangerous Goods3.
Class 5: Capacity to oxidise – not triggered
5.1 – Oxidising
substance not
organic peroxide
The fluoropolymers may contain the elements oxygen,
fluorine, chlorine, but since they are only covalently
bonded to carbon they will not have oxidising
properties.
5.2 – Organic
peroxide
Fluoropolymers do not meet the definition of an
organic peroxide.
Class 6: Toxicity – not triggered
Due to the high strength of the carbon/fluorine bond and the repelling properties of the
fluorine atoms, the fluoropolymers are extremely inert physiologically and are in fact
used for human organ prostheses4.
6.1 – Acute toxicity
threshold: oral LD50
≤ 5000 mg/kg
Rats fed PTFE at a level of 12.5 g/kg showed no toxic
effects5. The oral LD50 of the terpolymer (vinylidene
fluoride-haxafluoropropylene-tetrafluorethylene) was
>40 g/kg. Rats fed the vinylidene fluoridehaxafluoropropylene copolymer at 12.5 g/kg showed no
clinical or nutritional signs of toxicity6.
Page 11 of 19
6.3 – Skin irritant
PTFE does not produce skin irritation5. Polyvinyl
fluoride tested negative for skin irritation6. Skin
irritation tests on the terpolymer (vinylidene fluoridehaxafluoropropylene-tetrafluorethylene) and the
copolymer vinylidene fluoride-haxafluoropropylene
produced only mild and transient responses6,
insufficient to trigger HSNO thresholds.
6.4 – Eye irritant
Eye irritation tests on the terpolymer (vinylidene
fluoride-haxafluoropropylene-tetrafluorethylene) and
the copolymer vinylidene fluoride-haxafluoropropylene
produced only mild and transient responses6,
insufficient to trigger HSNO thresholds.
6.5A – Respiratory
sensitiser
No specific data available
6.5B – Skin
sensitiser
PTFE has not been found to act as an allergenic agent6.
Polyvinyl fluoride tested negative for skin
sensitization6.
6.6 – Mutagen
No specific data available
6.7 – Carcinogen
While no animal studies have demonstrated that
polytetrafluoroethylene is carcinogenic6, the
International Agency for Research on Cancer (IARC)
classifies PTFE and organic polymeric materials in
general as Group 3 – not classifiable as to their
carcinogenic effects5,7. Under HSNO they are therefore
not classified as a carcinogen.
6.8 – Reproductive
/ developmental
effects
No specific data available
6.9 – Target organ
systemic effects
A 90 day feeding study of rats with PTFE at levels up
to 12.5 g/kg bw/day showed no signs of toxicity5. A 10
month oral PTFE feeding study in rats showed no effect
on the animals8.
Class 8: Corrosiveness – not triggered
8.1 – Corrosive to
metals
Fluoropolymers are not listed in the UN
Recommendations on the Transport of Dangerous
Goods3 and there are no data to indicate that they are
corrosive to metals.
8.2 – Corrosive to
dermal tissue
Fluoropolymers are not listed in the UN
Recommendations on the Transport of Dangerous
Goods3 and as they are not skin irritants cannot be
corrosive to the skin.
Page 12 of 19
8.3 – Corrosive to
ocular tissue
Fluoropolymers are not eye irritants and so cannot be
corrosive to the eye.
Class 9: Ecotoxics – not triggered
As discussed under Class 6 – Toxicity, fluoropolymers are inert biologically, of high
molecular weight and so are highly unlikely to adversely affect marine, soil or
terrestrial vertebrates or invertebrates. Although they may not be rapidly degraded
and so may persist in the environment, fluoropolymers are inert substances that are not
bioavailable and hence will not bioaccumulate.
5
ERMA New Zealand classification
The transfer group has already classified polytetrafluoroethylene as non-hazardous.
6
Foreign regulatory agencies guidelines:
Fluoropolymers of molecular weight > 1,000 meet the USEPA polymer exemption
rule and the NICNAS polymers of low concern criteria as listed in the appendix9.
Furthermore, various fluoropolymers are permitted by the US Food and Drug
Administration (USFDA) “as articles or components of articles intended for use in
contact with food” (CFR Title 21 §177.1380, §177.1550, 177.2510).
6.
Nature of determination sought:
Whether the substance is hazardous under HSNO.
CHECKLIST
Yes
Mandatory sections filled out
Appendices enclosed
Yes
Fees enclosed (refer to Schedule of Fees
and Charges on website
www.ermanz.govt.nz)
NA
Application signed and dated
Yes
Signed
Date
Page 13 of 19
Appendix
7
General notes
Limited specific data available
Polymers, in the form of plastics and rubbers have been around for many years (1862
saw the first synthetic plastic – cellulose nitrate, 1931 the first synthetic rubber,
neoprene). They have become ubiquitous in our daily lives as they have versatile
properties. There has been widespread exposure to a variety of plastics over the years
and very few reported cases of actual adverse effects. Plastics are therefore generally
considered non-toxic and safe and consequently only very limited investigations have
been carried out into the potential harmful effects of polymers.
Explosiveness
The organic polymers detailed in this application are not explosive as they pass the
‘screening procedures for substances which may have explosive properties’ as laid out
in the User Guide to HSNO thresholds and classifications2.
Flammability
High molecular weight organic polymers are solid, non-explosive substances, and so
the HSNO Class 2 (Flammable liquid), the HSNO Class 3 (Flammable liquid and
liquid desensitised explosive) and HSNO Class 4.1.3 (solid desensitised explosive)
will not apply. The organic polymers also pass the screening procedures for HSNO
Classes 4.1.2, 4.2 and 4.3 as laid out in the User Guide to HSNO thresholds and
classifications2. While most synthetic organic polymers will burn, just like the natural
organic polymer of cellulose (found in wood/paper) when sufficient heat is applied to
them, they are considered slow burning with some actually self-extinguishing or flame
retardant. They will not be able to trigger the HSNO 4.1.1 readily combustible solid
threshold.
Toxicity, Ecotoxicity
Polymers, by their very definition, are high molecular weight entities. Such large
macromolecules are not able to cross lipid membranes into cells where the effects of
toxic chemicals usually unfold. Polymers are therefore considered biologically inert
as they are not bioavailable4,6, and are unlikely to trigger HSNO toxicity (Class 6) and
ecotoxicity (Class 9) thresholds. Observed biological effects of polymers can be
traced back to incompletely reacted monomer, solvents or other non-polymeric
materials.
Oral toxicity studies
Overall toxicity of polymers is very low, the LD50 values are often above the limits of
practical experimental testing6 and so will be above the HSNO Class 6.1 (acute
toxicity) threshold. Indeed, adverse effects in long term animal feeding studies are
most often the result of bulk amounts of polymer physically causing decreased food
intake and so compromising the nutrition of the animal10 and not due to any target
organ/systemic toxicity that may trigger HSNO Class 6.9.
Page 14 of 19
General irritation
Potential irritating effects of polymers to the respiratory tract, skin and eyes can be
ascribed to physical action only10, which will not trigger HSNO Class 4 (skin
irritation) and Class 5 (eye irritation) thresholds.
Eye irritation
Completely polymerised plastics that are free from small molecular weight compounds
are generally inert. No toxicity to the eye is observed, except for such irritation as
small foreign bodies cause when in the conjunctival sac or cornea11. Such physical
effects will not trigger the HSNO Class 5 (eye irritation) threshold.
Dust
Most polymers are imported into the country in the form of pellets – too large to be an
inhalation hazard. Some however, (for example PVC) may be of small enough size to
be inhaled. Some cases of lung disease after prolonged exposure to PVC dust have
been reported. The physiological response of the tissue to the dust is consistent with
similar chronic exposures to other unreactive particulates as found, for example, in
coal miners’ disease6. Limited data are available on the effects of other polymer dusts.
Based on the low toxicity of polymers however, any adverse responses are most likely
due to the physical presence of foreign particulate matter in the lungs. Such physical
effects will not trigger HSNO Class 6.5A (respiratory sensitisation), Class 6.7
(carcinogenic effects) or Class 6.9 (target organ systemic effects). Proper industrial
hygiene procedures should be followed around polymer dust, as around any other type
of dust.
Carcinogenicity
Again due to their high molecular weight, polymers are highly unlikely to have
carcinogenic or mutagenic effects. Some experimental investigations have shown that
implantation of polymer material into subcutaneous, intraperitoneal, intramuscular and
intrauterine tissue has resulted in some local sarcomas. Their incidence, however, is
highly dependent on physical form of the implant. Roughening of the surface of the
implant reduces the sarcoma incidence, often to nil with the segmentation or
pulverisation of the material7. This is indicative of the so-called ‘solid state
carcinogenesis’ which is critically dependent on the physical nature of the implant,
rather than its chemical composition10,12. Overall, the International Agency for
Research on Cancer (IARC) classifies organic polymeric materials as Group 3 – not
classifiable as to their carcinogenic effects5,7, which means they are not classified as
carcinogenic under HSNO Class 6.7.
Solubility
The majority of high molecular weight organic polymers are insoluble in water. This
means they are effectively not bioavailable to aquatic organisms, and so will not have
any HSNO Class 9.1 aquatic effects.
Polymer exemption rule (Polymers of Low Concern)
The US Toxic Substances Control Act (TSCA) of 1976 was enacted to test, regulate,
and screen for any toxic effects, all chemicals produced or imported into the United
States. In 1984 the Environmental Protection Agency (EPA) which administers the
Page 15 of 19
Act identified certain criteria to determine which polymers were most unlikely to have
any toxic or ecotoxic effects. These polymers were exempted from having to be
notified to the Agency under the Polymer Exemption rule so established (Code of
Federal Regulations Title 40 §723.250). A similar scheme has been adopted by the
Australian National Industrial Chemicals Notification and Assessment Scheme
(NICNAS), called “Polymers of Low Concern”. Both schemes recognise the inherent
non-toxicity of high molecular weight molecules, with polymers above 10,000 amu
exempt from reporting as long as they meet certain other criteria:






8
The oligomer content must be <2% of oligomers of size below 200 amu and <5% below
1,000 amu.
The polymers must not be cationic or reasonably expected to become cationic in a
natural aquatic environment as they may be able to cause a pH change and so be toxic
to aquatic organisms.
Residual monomer or impurity must not trigger any hazard thresholds
The polymer must meet certain elemental criteria (restricting the types of elements
permitted as an integral part of its composition).
The polymer must be stable, i.e. it must not degrade, decompose or depolymerise
substantially after manufacture and use. This does not include the slow, natural
biodegradation.
Polymers must not be water absorbing (i.e. capable of absorbing their own weight in
water) due to the proven risk of lung damage after inhalation of water absorbing
polymers.
Lower molecular weight polymers may also be exempt, depending on the nature of
their functional group – the less reactive the functional group, the lower the molecular
weight requirement.
Glossary of Terms
H2C
Acrylic/methacrylic esters:
O
O
O
R1
H2C
O
R1
CH3
Aliphatic hydrocarbon: a hydrocarbon with an open chain (acyclic) structure.
Amide
linkage:
O
R1
N R2
H
Aromatic: having one or more benzene ring.
Atomic mass unit (amu): exactly one twelfth the mass of a neutral atom of the most
abundant isotope of carbon, 12C. 1 amu = 1.660 x 10-27 kg. Also called the Dalton.
Carbonate
linkage:
O
R1
O
O
R2
Page 16 of 19
Cationic /Potentially cationic: as defined in the NICNAS Synthetic Polymer of Low
Concern Guidance Document.
Copolymer: a polymer made of two different monomers.
Engineering thermoplastics: thermoplastics used in structural or engineering
applications, or in applications replacing metals. Usually have high strength and
rigidity and maintain these properties over a broad range of temperatures.
Ester
R1
Ether
linkage:
O
R1
O R2
O
R2
linkage:
Functional group: an atom or associated group of atoms with chemically active
bonds. (Usually most things other than C-C or C-H single bonds).
Heteroatom: in an organic compound, any atom other than carbon or hydrogen.
Homopolymer: a polymer made up of only one type of monomer (neglecting the
ends, branch junctions, and other minor irregularities).
Hydrocarbon: a substance consisting only of carbon and hydrogen atoms.
Monomer: a relatively simple compound which can react with other like or unlike
monomers to form a chain; the basic building block of the polymer.
Olefin (alkene): unsaturated hydrocarbon, of general formula CnH2n.
Oligomer: low molecular mass polymer formed from two or more monomer units
linked together.
Polymer: a high-molecular-weight compound, natural or synthetic, characterised by
the repeating sequence of one or more types of monomer units.
R1/R2: generic alkyl group.
Reactive functional group: a functional group that is intended or can be reasonably
anticipated to undergo a facile chemical reaction.
Terpolymer: copolymer of three different monomers.
Thermoplastic: any resin which can be melted by heat, reshaped and then cooled.
The process is in theory repeatable any number of times without a change in
properties.
Page 17 of 19
Thermoset: plastics which undergo chemical reactions (such as crosslinking) upon
moulding which results in a vast network molecule, held together by covalent bonds,
making the product resistant to further applications of heat (until the charring point).
H
H2C
Vinyl group:
C
R
R2
Vinylidene
H2C
C
R1
group:
Water absorbing polymer: a polymer capable of absorbing its own weight in water.
9
References
1
Know your plastics. Plastics Industry Association, 1992.
2
User Guide to the HSNO Thresholds and Classifications, ERMA New Zealand, 2001.
Recommendations on the Transport of Dangerous Goods. Model Regulations. 12th ed. United
Nations, Geneva, 2001.
3
Hamilton A. and H.L. Hardy. “Plastics” in Industrial Toxicology, Third Ed. Publishing
Sciences Group, Inc., Acton, Massachusetts, 1974.
4
5
IARC Monograph 19, 1979.
6
Patty’s Industrial Hygiene and Toxicology. John Wiley & Sons, 2001.
7
IARC Monograph 74, 1999.
8
Sheftel, V. O. Indirect Food Additives and Polymers: Migration and Toxicology. Lewis
publishers, 2000.
9
Polymer Exemption Rule, Code of Federal Regulations Title 40 §723.250.
Drew, R. “Toxicity of plastics.” In Occupational Toxicology, N. H. Stacey, Ed.. Taylor and
Francis Ltd. London, 1993.
10
Page 18 of 19
Grant, W. M. Toxicology of the Eye. 2nd ed. Springfield,
Illinois: Charles C. Thomas, 1974.
11
Lewis, R. “Plastics” in Occupational Medicine, J. LaDou, Ed. Appleton and Lange,
Norwalk, Connecticut, 1990.
12
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