Guidance and Criteria For Safe Recycling
Guidance and Criteria For Safe Recycling
Guidance and Criteria For Safe Recycling
1)
Fraunhofer Institut für Verfahrenstechnik und Verpackung (IVV), Freising, Germany
2)
The Coca-Cola Company, Atlanta, USA
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Foreword
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solvents per day. As an overall conclusion from the project results and from many
other findings and considerations it can be concluded that modern super-clean
technologies can safely reprocess PCR PET into new materials and articles for
direct food applications in the same and which are indistinguishable from virgin
food grade PET.
The results from this study were the necessary and a suitable scientific basis to
allow the writing of this guidance document for the safe recycling and use of PCR
PET. It is the wish of the project coordinator that this document will lead to a
situation in Europe which allows safe PET recycling in all European member
states as well as other countries, so they wish, according to harmonised test
protocols which, however, should contain sufficient flexibility to meet further
technological and scientific progress in this field. Furthermore, the proposed test
protocols have been designed such that to the best of our knowledge and
experience also a harmonisation with US FDA requirements has been achieved.
The project coordinator, also on behalf of the co-authors, wishes to express his
thanks to all involved laboratories, industries and other stakeholders inclusively
the project officers from DG Research from the European Commission (for a
complete list see under Chapter 9).
Roland Franz,
Coordinator of EU project FAIR-CT-98-4318
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Contents
1. Introduction 1
2. Definitions 3
3. Categories of PET recycling feedstocks and process technologies 5
3.1. Conventional reprocessing or recycling 6
3.2. Super-clean recycling technologies 6
4. Historical perspectives and global status of PCR PET in food applications 7
4.1. The United States 7
4.2. Europe 7
5. Technological principles and strategies to ensure high PCR PET quality 9
5.1. Recollection systems 9
5.2. Conventional recycling processes 9
5.3. "Super-clean" processes 10
6. Cleaning efficiency testing of reprocessing technologies 11
6.1. Selection and application of surrogates for input from food packaging
applications as feedstock 12
6.2. Selection and application of surrogates for input from non-food
packaging applications as feedstock 16
6.3. Practical instructions for challenge tests 16
7. Evaluation of (potential) surrogate migration 18
7.1. Evaluation of migration by calculations 18
7.2. Manufacture of model food contact articles 19
7.3. Migration testing 19
8. Quality assurance 21
8.1. Frequency of the challenge test 21
8.2. Analytical monitoring 21
8.3. Sensory testing 22
9. Acknowledgements 23
10. References 24
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Abbreviations
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1. Introduction
In the past few years essential under the pressure of new ecological demands [1]
enormous technological progress has been made in the area of decontamination
of "post-consumer" plastics, in particular from the PET beverage bottle market.
The development of modern recycling processes increasingly allows cleansing
and reconditioning of "post-consumer" recycled (PCR) PET for being reused in
direct food contact applications. In parallel, research, carried out in connection
with this technological development, has provided an enormous increase in
knowledge which allows today to assess with sufficient confidence and safety the
extent of interaction processes of possible recycling specific contaminants
between PET bottles and the filled foodstuff [2 - 12 and numerous other papers
cited therein].
Current and future worldwide beverage packaging PET consumption is
characterised by annual increase rates of 9%. As a consequence, this
development is paralleled in Europe by industrial investments into new PET
recollection and recycling capacities by at least the same increase rates [13]. The
currently by far greatest application market for PCR PET which is fibres for
textiles and carpets may approach saturation in the near future with the effect
that food packaging applications will be of increasing economic and therefore
consumer safety interest.
In the manufacture of articles from primary plastics there is normally perfect
control of the starting raw materials used. For post-consumer materials complete
control of the material is not possible. Here it can be expected that substances
are introduced which are untypical for polymers, above all components from the
filled product from the first use but also from misuse by the consumer and that
corresponding contamination of the post-consumer material occurs.
As is generally known, plastics can interact with organic chemicals. The extent of
this interaction moreover depends on the diffusion behaviour specific to polymers
and the sorption properties of the plastic. These physical properties ultimately
determine the potential risk of food contamination due to recycling. In relation to
this aspect, PET possesses much more favourable material properties in
comparison to other packaging plastics, such as polyolefines or polystyrene and
is, therefore, much better suited for mechanical recycling for being reused in the
food commodity sector.
Recycling processes for the manufacture of recycled PET as a final product,
which is food legally safe, must include process steps which efficiently deep
cleanse the plastic and eliminate substances which originate from the first use or
possible misuse. It is, therefore, imperative in this highly sensitive field that the
recycler of post-consumer material demonstrates in a worst-case scenario that
even under the most unfavourable conditions conformity with the law on food and
commodities is ensured for the articles partially or completely manufactured from
recycled material.
One objective of this document is to summarise the state of the art in PCR PET
reprocessing into new packaging applications for direct food contact from a
historical/food legal point of view and with rather short notices on technology
aspects. The major intention, however, is to give practical guidance and a reliable
criteria for the safe recycling and use of PCR PET in this challenging market
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2. Definitions
Adventitious contaminants:
Any unwanted substance that deliberately or inadvertently comes into contact
with the packaging material before it is collected for recycling and that therefore
may contaminate the plastic and negatively influence the quality of the product
filled by a recycled packaging material.
Challenge test:
A test of the effectiveness of a super-clean recycling process to remove chemical
contamination from materials or articles. The test involves introduction of
exaggerated levels of surrogates and includes as an end parameter the migration
evaluation of these surrogates from a model food contact article. As a safety
criterion this migration must not exceed 10 µg kg-1 (ppb) food. This can be
considered to be a purely technical cleaning efficiency criterion which
demonstrates the powerfulness of a super-clean recycling process.
"Conventional" PET recycling:
A recycling procedure using the process steps grinding, washing and surface
drying of recollected PET containers. The output material of conventional
recycling processes are PET flakes customary used for non-food or for the core
layer of multi-layer applications. Conventional recycled PET flakes are usually
used as input material for so-called super-clean recycling processes.
Consumption factor (CF):
Generally, CFs are used to correct a migration test result (measured
concentration in food simulant) into a exposure value (average uptake by the
consumer with the diet). Specifically, the US FDA defines CF as the plastic
packaging usage factor which is CF = 0.16 for virgin PET and CF = 0.05 for any
recycled PET. In Europe, the system of packaging usage factors has not been
established yet. However, the concept of fat consumption factors has recently
been adopted with the consequence that a fat reduction factor (FRF) will be
introduced into European legislation (future amendment of Directive 85/572/EC).
Extraction:
Quantitative dissolution of constituents from a plastic into a solvent and based on
a strong interaction between plastic and solvent.
Feedstock/feedstream:
Post consumer PET plastics used as raw materials for recycling.
Food grade PET:
For Europe: PET plastic of a suitable standard for food applications manufactured
in compliance with EU Directive 2002/72/EEC (and future amendments). For USA:
the PET plastic must be compliant with 21 CFR 177.1630 and 21 CFR 177.1315.
It should be noted that food grade PET is also used for non-food packaging
applications.
Migration:
Diffusion-controlled mass transfer from a packaging material or article to food or
simulant. Classically, migration is experimentally determined by standardised
tests using food simulants. Due to the scientific progress in this field, today
migration can also be mathematically modelled and conservatively predicted.
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Migrations limits:
Food regulatory maximum concentrations of migrants in food simulants or
foodstuffs resulting from a migration process. With respect to the sensitive area
of recycled food packaging materials and articles, the legally prescribed overall
migration is of much lower relevance and importance than specific migration
limits as for instance defined also by a threshold of no concern.
Post consumer recycle PET (PCR PET):
PET plastic material (bottles/containers) that has been manufactured, distributed
and used by the consumer. Discarded PCR PET material becomes the feedstock
for recycling processes.
Post industrial recycle PET:
Industrial inhouse plant scrab generated during the manufacture process which
may be reused in the production of new bottles.
"Super-clean" PET recycling:
In most instances the process uses as a source the output material from
conventional recycling, for example washed and surface-dried PET flakes, and
includes one or more additional cleaning steps. The output of "super-clean"
processes may be used for packaging applications in direct contact to the
foodstuff provided they meet the appropriate regulatory guidelines or legal
requirements.
Surrogates:
Organic compounds (also known as "model contaminants") of a wide range of
chemical types and physical properties representing exaggerated contamination
to challenge the safety of recycled materials and articles. Possible application
may be as individuals or a test mixture.
Threshold of no concern:
A concentration of a migrant in a foodstuff which, from a toxicological point of
view, is considered to pose no health risk to the consumer even in case that the
chemical structure of the migrant is unknown. As an example the US FDA
threshold-of-regulation concept according to 21 CFR 170.39 may serve where
-1
the threshold, understood as the daily dietary intake, is set at 0.5 ppb (µg kg
food).
In Europe, this concept is under discussion but a general threshold value has not
yet been adopted. However, specifically for evaluation of the safety of super-
clean processes the purely technical cleaning efficiency criterion (see challenge
test) is applicable. A JECFA task force of FAO/WHO has adopted the utilisation
of a threshold of toxicological concern concept for the evaluation of flavouring
substances in food. The proposed no concern level was 1.5 µg per person per
day [15, 16].
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In general, feedstock materials for PET recycling processes can be divided into
the four quality classes [17, 18]:
Class 1: Materials remaining from production by the manufacturing or
converting industry where their past history is known and which have
always been under the control of the processor. Provided that good
manufacturing practice is followed and contamination can be
excluded, this material is as suitable for direct contact with foodstuffs
as new material.
Class 1 material can be defined as "post industrial recycle PET" and corresponds
to US FDA's Primary Recycling (pre-consumer scrap).
Class 2: PCR PET material which had been used for food packaging for well-
known applications and recollected pure-grade by the recycler, for
instance via a deposit system or material collection. Due to its post-
consumer character, the recycler usually does not have complete
control of the plastics material over the time period from its first use
up to its return.
Class 3: Impurified PCR PET material and possibly commingled with other
plastics which had been used for certain applications also outside of
the food packaging area and enters the recycling feedstream via
mixed plastics collection, for example such ones as operated by the
"green dot" collections. The material could include also food-grade
PET from non-food packaging applications.
Both, class 2 and 3 correspond to US FDA's Category "Physical reprocessing:
Secondary Recycling".
Class 4: Any class 1 to 3 material which had been chemically reprocessed by
depolymerisation into monomers or oligomers from which after
purification a new polymer has been regenerated.
Class 4 corresponds to US FDA's Category "Chemical Reprocessing: Tertiary
Recycling".
From given reasons, class 1 and class 4 feedstock materials can be considered
to be safe and in compliance with the legal requirements and are not anymore
dealt with in the further discussion.
Secondary recycling of class 2 and class 3 materials is economically and from a
mass fraction standpoint of highest interest and challenge with regard to
consumer safety considerations. It must be noted that "eligible" feedstock PET
material must be of "food grade" quality. Furthermore, it should also be noted that
it has been verified by industry that PET produced for both food and non-food
(e.g. personal hygiene products and household cleansers) containers is
compliant with EU Directive 2002/72/EEC as well as 21 CFR 177.1630 and
21 CFR 177.1315 [9, 18, 19].
For further discussion an additional differentiation concerning recycling process
technologies is necessary.
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4.2. Europe
Industry has pressed for the issuance of an EU Directive on recycling since the
early 90s. To-date no such Directive exist. This has necessitated interested
members of industry to seek approval from the individual member states of the
European Union or European country governments. The United Kingdom was the
first country in Europe to issue a letter of no objection for the use of post-
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consumer recycle PET for process via depolymerisation for direct food contact
use in 1992. Since that time both multilayer and monolayer (direct contact/super-
clean processes) have been given clearance via letters of no objection or
approval by a number of the European countries. Multilayer has received
clearances for use in Austria, Belgium, Finland, France, Norway, Sweden and the
United Kingdom. The monolayer direct contact approach has received clearance
for use in Austria, Belgium, France, Germany, The Netherlands, Norway,
Sweden and Switzerland. The heterogeneity in Europe is most clearly indicated
by the fact that in some countries such as Italy or Spain plastics recycling into
direct food packaging application is currently still prohibited.
The continuing need for guidance in assessing the use of PET recycling
technologies in food contact applications resulted in a workshop being sponsored
under the auspices of the International Life Science Institute (ILSI) Europe
Packaging Material Task Force. The workshop participants consisted of
representatives from many of the major European Regulatory/Independent
Industrial Research Laboratories, representatives from major industry companies
and representatives from the European Commission, Directorate – General III.
Two years of diligent work resulted in the issuance of guidelines for recycling of
plastics for food contact use in May 1998 [22]. These guidelines contain eight key
recommendations. And for all practical purposes parallel the US FDA guidelines
with the exception of the bases of the end point. US FDA guidelines base their
end point on the concept of the Threshold of Regulation whereas the ILSI
guidelines focus on an end point of demonstrating no detectable migration at the
limit of detection of analytical methodology. It should be noted, however, the final
end point in both instances i.e. the Threshold of Regulation and the non-
detectable migration limit are in fact the same value for PET recycling (10 ppb or
-1
µg kg ).
In 2000, the German BfR (the former BgVV) has issued a statement to ensure
the safe mechanical recycling of plastics made from polyethylene terephthalate
(PET) for the manufacture of articles for direct food contact. This statement which
has been adopted under BfR recommendation XVII for PET [17] introduces
additionally two interesting novelties: (i) the concept of analytical quality
assurance connected with the requirement that PCR PET products must not be
disadvantageously distinguishable from virgin material and (ii) the 10 ppb
migration limit for surrogates as a technical cleaning efficiency criterion for
evaluation of the super-clean process capability and not understood as a
toxicology based end parameter.
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The use of PCR PET in food contact applications must assure for the safety of
the material. The concern is that the consumer may have used the
bottle/container for mixing or storing some adventitious substances prior to
disposal thus generating an unwanted migration potential in the PET material.
Therefore it is necessary to ensure that any recycling process has the ability to
render these materials safe for the food contact application.
The first approach to manage these potential problems was addressed by the
US FDA guidelines of 1992 [21]. At this time the relative incidence of the
contamination rate in the PCR PET feedstreams was not known and
consequently FDA took the position that one must contaminate 100 % of the
feedstock for testing. The test that was recommended is called a "challenge test"
which is used to establish the efficacy of the recycling technology and the
involved cleaning steps. In this challenge test, organic chemicals with varying
chemical and physical properties are introduced into the PET material which is
then carried through the complete washing and recycling process to be
assessed. The organic substances serve as model contaminants or so-called
surrogates. It is important that the contamination must be carried out such that
considerable amounts of chemicals can diffuse into the plastic material. The
initial concentrations of the surrogate contaminants must be sufficiently high
enough to establish a worst-case scenario for the recycling system to be
assessed or, if necessary, the modular cleaning step which is to be checked.
Concerning the question, however, what exactly must be understood by these
worst-case challenge test conditions, there was an enormous increase of
research data in the past decade and particularly in the last three years through
the FAIR-CT98-4318 project as well as other relevant studies [7, 8, 9, 10, 11, 12,
14].
For PET, US FDA originally [21] recommended a set of five surrogate categories
where each set stands for a different chemical polarity and volatility and where
the individual surrogates should represent certain "common" materials which are
accessible to the consumer and therefore potential candidates for misuse or
abuse of plastic containers. One of the five categories should represent heavy
metals but was deleted again for PET challenge testing because, based on new
scientific data, it is not considered to constitute a regulatory issue [18]. The
applicable initial concentrations of these surrogates are defined by the test
protocol through the recommended concentrations of surrogates in the
contamination cocktails and the time and temperature conditions (14 d at 40 °C)
recommended for the soaking procedure. Undoubtedly, this approach represents
more than a worst-case scenario, since it simulates the scenario that all PET
food container material entering the recycling stream is contaminated practically
at maximum possible levels. For inclusion of non-food containers (of initially food
grade PET quality) into the feedstream, FDA has specified the minimum
concentrations of surrogates to be used on the basis of sorption equivalents
achievable after a one year storage at around room temperature. Depending on
the chemical structure of the surrogate the required initial target concentrations
range from 49 ppm (benzophenone) to 1100 ppm (trichloroanisole) with two
exceptions (chloroform and diethyl ketone) set at 4860 ppm each.
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In Europe, the experts from the above-mentioned ILSI workshop came to the
conclusion that for ensuring a sufficient safety margin a factor of 10 should be
applied to both factors influencing the level of surrogates introduced by the
challenge test. These factors are: (i) the concentration of surrogates used to
contaminate the articles and (ii) the number of articles or weight of flakes to be
contaminated (i.e. the amount of contaminated recycled material to be used in
the test). With respect to each factor, the guide sticks on the one hand to the
FDA guidelines recommending the same surrogate concentrations and 100 %
contamination but offers, on the other hand, also relaxed requirements based on
sound evidence of actual likely incidence of the contamination in practice [22]. At
this time, however, typical contamination levels were not known and
consequently the final factor which is the product from both contributions (i) and
(ii) remained undefined. This fact was indeed one of the driving forces to initiate
the EU project [14] in which exactly this open question was resolved.
The German position as laid down by BfR recommendation XVII [17]
recommends as a sufficient initial challenge test concentrations a range from
500 ppm to 1000 ppm per surrogate contaminant for checking the entire process.
This document states also that addition of too high initial concentrations can have
a negative effect on the processability of the contaminated material within the
challenge test and may lead to technical difficulties during the manufacture of the
recycled material and the surrogates containing model article. In addition it says
that the specified concentration range includes a safety factor of 100 to 1000 in
relation to the real maximum occurring initial feedstream concentrations of
foreign substances which are untypical for PET in recycled PET and which do not
come from the previously filled foodstuff.
As an assessment criterion for the sufficient cleaning efficiency of the recycling
process all of the above mentioned documents have in common that the final
measurable migration of the spiked surrogates from a model food contact article
-1
into a food simulant must not exceed of 10 ppb (µg kg ).
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The selected surrogates cover not only a wide spectrum of volatility and polarity
properties but also the full range of migration-relevant molecular weights. Due to
its inherent low diffusivity PET allows under normal food packaging filling and
storage conditions relevant migration of its constituents up to a molecular weight
of around 350 g mol-1. Substances with higher molecular weights do not play a
role anymore in migration and are nearly immobilised in the polymer matrix, if
present. This is illustrated by Figure 1 which models the migration after 10 d at
40 °C from PET in dependency of the molecular weight of a migrant and its
residual content CP,0 (migration model applied as described in [23]). According to
this figure and assuming a CP,0 = 10 ppm for any PET constituent, toluene
(MW = 92) as a surrogate would give a migration value of approx. 7 ppb whereas
methyl stearate (MW = 298) migrates at approx. 2.4 ppb only. Or when defining
the maximum initial concentration (MIC in ppm) of a surrogate in PET which
corresponds to a migration value of 0.01 ppm (10 ppb) in food simulant then the
following ratios of MIC values can be derived for contact conditions 10 d at 40 °C
(see Table 2). It should be noted that two MIC columns have been generated
each with a different AP value where the AP = 1 values are overconservative and
too exaggerating (compare discussion under 7.1).
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developed [7, 11] working with a mixture of the surrogates at higher temperature
(50 °C) and shorter time (7 d). This procedure which is much more convenient
with respect to the handling steps was found to be equivalent to the "classical"
FDA soaking procedure. Furthermore, it avoids production of excessive chemical
waste due to quantitative absorption of the surrogates.
Following this new quantitative absorption procedure the surrogates are applied
to PET flakes such that after the absorption phase the contaminated PET flake
batch should contain approximately 500 ppm to 350 ppm of the above listed
surrogates where the more volatile surrogates such as toluene should approach
the 500 ppm level and the most non-volatile compound (methyl stearate) may be
present rather at the lower 350 ppm level. The so-contaminated PET flake batch
is introduced directly into the super-clean process which is to be assessed.
Therefore, taking cleaning efficiencies of conventional recycling technologies of
20 % to 80 % (achieved by washing and flash-drying) and finally 89 % to 99 %
(achieved by pervasive drying for extrusion) into account [24, 25], this
recommended concentration range of 500 to 350 ppm contains a large safety
margin because it translates to much higher concentrations (at 80 % wash
efficiency: 2500 ppm to 1750 ppm) in comparison to the classical FDA approach
where the soaked PET flakes undergo at first a conventional washing and drying
process before being further deep-cleansed by a super-clean process.
When comparing the above recommended surrogate concentration ranges with
the EU project findings from conventionally recycled PET flakes then the
following safety factors (washing and drying effects are already excluded) can be
discussed. It should be noted that these safety factors do not include the effect of
the super-clean process which reduces the contamination concentrations to non-
detectable levels [12].
With respect to PET unspecific compounds which, however, are food constituents
from the first use, and more specifically for limonene:
• Maximum level found : 20 ppm, i.e. safety factor range from 18 to 25.
• 98 percentile level found: 10 ppm, i.e. safety factor range from 35 to 50.
• Average concentration found: 2.9 ppm, i.e. safety factor range from 120 to
170.
With respect to PET unspecific compounds such as phthalates, adipates,
erucamide etc. which had a technological function (for instance softener or
lubricant) as an additives in the first application and were introduced as external
contaminants from residues of other polymer types, affixed labels, closures and
others. Observed concentrations ranged around the detections limits of
approximately 0.05 to 0.2 ppm with a maximum value of 0.5 ppm found in one
case for dioctyl adipate. Taking the highest, singular observation of 0.5 ppm then
safety factors range from 700 to 1000.
With respect to misuse chemicals, the PET recycling feedstream contains 1.4 to
2.7 ppm. Using 3 ppm as an upper limit value the safety factors range from 120
to 170.
In conclusion, science and practice have demonstrated that both the US FDA
soaking procedure (14 d at 40 °C) and the above mentioned alternative elevated
temperature contact approach (7 d at 50 °C) are suitable to evaluate
decontamination technologies with respect to their potential of producing
regulatorily acceptable food grade recycled PET qualities. The preferred
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If it is found from the 100 % mass transfer approach that potential migration
would exceed the 10 ppb criterion then mathematical models can be applied for
further evaluations. A generally recognised migration model based on diffusion
coefficient estimation or organic chemical substances in polymers [28] has been
recently finished within the European project SMT-CT98-7513 "Evaluation of
Migration Models in Support of Directive 90/128/EEC" [29]. For migration
estimation of surrogates from PET, however, this migration model turns out to be
overconservative [measured surrogate migration data from 7, 8, 11 in
comparison to calculated ones, 18]. According to [29] the efficient PET diffusivity
at 40 °C is described by a value AP = 1 whereas the more realistic diffusion
behaviour is described by AP = -1. This value is still overestimative and was
therefore used for Figure 1 and included also in Table 2. This table can serve as
an indication whether residual contents of surrogates will lead to migration
exceeding the 10 ppb criterion. It is recommended to allow for a sufficient safety
margin to ensure fulfilling the 10 ppb requirement. Therefore the values found in
the AP = 1 column can be considered as the MIC limits below which migration
tests are totally superfluous. With increasing values above the AP = 1 MIC limits
migration testing is more and more recommended and even necessary when the
AP = -1 MIC limits are approached.
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The assessment criterion to decide whether the challenge test has passed the
crucial requirement of efficient removal of potential contaminants is defined by a
maximum migration rate leading to a concentration of 10 ppb (µg l-1) in the food
simulant. It must be noted that initial surrogate concentrations introduced by a
challenge test into a super-clean process range several orders of magnitude
higher compared to what can be found in reality. Therefore, reduction of these
initially high concentrations to such low levels in the challenge test product or in
the model food contact article which correspond with or lead to migration values
smaller than or equal to 10 ppb demonstrates the deep-cleansing efficiency of
the technology and is not connected to any consumer exposure considerations.
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8. Quality assurance
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9. Acknowledgements
This work was largely funded by the European Union under contract FAIR-CT98-
4318 ("Recyclability of PET, paper&board and plastics covered by a functional
barrier for food packaging"). The findings and the conclusions in this paper are
the responsibility of the authors alone and they should not be taken to represent
the opinion of the European Commission.
The authors gratefully appreciate pleasant cooperation with all of the project
partners involved in section I (PET) of the project. These partners are:
• Dr. Laurence Castle and Mr. Mark Philo, DEFRA Central Science Laboratory,
York, United Kingdom
• Mr. Juha Lahti and Dr. Jari Vartiainen, VTT Biotechnology and Food
Research, Espoo, Finland
• Dr. Catherine Simoneau and Dr. Barbara Raffael, Joint Research Centre for
the European Commission, Institute for Health and Consumer Protection,
Ispra, Italy
• Prof. Christina Nerin, University of Zaragoza, Dept. Quimica Analitica, Centro
Politécnico Superior, Zaragoza, Spain
• Prof. Panagiotis Demertzis, University of Ioannina, Department of Chemistry,
Laboratory of Food Chemistry, Ioannina, Greece
• Mr. Rüdiger Fredl, Dr. Thomas Natter and Mr. Matthias Prebentow, OHL
Apparatebau & Verfahrenstechnik GmbH, Limburg/Lahn, Germany
• Mr. Caspar van den Dungen, ITW Poly Recycling GmbH, Weinfelden,
Switzerland
• Mr. Fritz Kehlert, Texplast GmbH, Wolfen, Germany
• Mr. Juan Carlos Ruiz, Envases de Plastico, Espila, Spain
• Mr. Osmo Bolander, WM Ympäristöpalvelut Oy, Jyväskyla, Finland
Moreover, the authors thank also Mr. Timothy Begley from the US FDA in
Washington for experimental contributions and helpful discussions.
Finally, fruitful cooperation with the Commission project officers from DG
Research, Dr. Alkmini Katsada and D r. Xabier Goenaga is greatly appreciated.
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10. References
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[13] Fritsch, C., Welle, F., Polyethylene terephthalate for packaging, Plast
Europe, 2002, 92(10), 40-41.
[14] Franz, R., Programme on the recyclability of food packaging materials with
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Guide to safe PCR-PET
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