Documents
Resources
Learning Center
Upload
Plans & pricing Sign in
Sign Out

Recycled Paper – Appropriate for Food Packaging?

VIEWS: 3 PAGES: 9

Packaging material made from recycled fibers contains unwanted substances that can contaminate food. A research project provided a plethora of information on these substances and their possible migration into foods.

More Info
									20.03.2013




Recycled Paper – Appropriate for Food Packag-
ing?

A research and “decision support” project of the Federal Ministry for
Food, Agriculture and Consumer Protection




                          Scrap paper as raw material for food packaging.


Packaging material made from recycled fibers contains unwanted
substances that can contaminate food. A research project provided a
plethora of information on these substances and their possible mi-
gration into foods.



                 Info Box
                 Report
                 Presentation of the results can be found in the final report of the „Altpapier-
                 Projekt” (Recycled Paper Project) (http://download.ble.de/09HS012.pdf)
                 as well as in the appendix to the report „Untersuchung von 119 in Karton




E                verpackten Lebensmitteln“ (Analysis of 119 Foods Packaged in Pa-
                 perboard Cartons) (http://download.ble.de/09HS012.pdf, from pg. 205).
                 Both reports can be downloaded free of cost as pdf data files from the
                 homepage of the Federal Office for Agriculture and Food (BLE). With your
                 understanding, however, the report will not be made available as printed
                 matter. Due to the confidential nature of some information within the appen-
                 dices, the data can´t be made available either in electronic or printed matter
                 form.



 ADDRESS Schaflandstraße 3/2 70736 Fellbach           E-MAIL Poststelle@cvuas.bwl.de
 PHONE +49 711 3426 - 1234                            INTERNET www.cvua-stuttgart.de
 +49 711 3426 - 1727 (Diagnostics)
 FAX +49 711 588176 +49 711 3426-1729 (Diagnostics)
Seite 2 von 9




Summary
For environmental and economic reasons, over 70% of paper is recycled
and turned into, among other things, recycled paperboard cartons. Ninety
percent of paperboard is produced with the addition of recycled paper.
(See “How my Cornflakes Box is Created from Recycled Paper”
http://www.cvuas.de/pub/beitrag.asp?subid=1&Thema_ID=3&ID=1767&la
ng=EN&Pdf=No). Many paperboard cartons used for food packaging are
also made of recycled paper. They contain unwanted substances such as
printing inks or adhesives that find their way into paper circulation. In the
project „Ausmaß der Migration unerwünschter Stoffe aus Verpackungsma-
terialien aus Altpapier in Lebensmitteln“ (“Extent of migration of unwanted
substances from packaging materials made of recycled paper and board
into food” http://download.ble.de/09HS012.pdf), the presence of 250 po-
tentially migratory substances were detected in recycled paperboard. Nei-
ther the choice of raw material nor the recycling process seems to be able
to reduce the amount of unwanted substances to an acceptable level. In
warehouse investigations mineral oil hydrocarbons, softeners, and printing
ink ingredients were found to have migrated from recycled paperboard
boxes into food. Boxed foods from the supermarket at the end of their
shelf life were markedly tainted with mineral oil hydrocarbons, softeners,
and printing ink ingredients. Introducing an inner barrier with plastic pack-
aging or layering the box could reduce such migration to a safe level.



Present Situation
Our food is often packaged today. The packaging is supposed to protect
the contents from contamination from outside influences, prevent microbial
spoilage and avoid mechanical damage. It also provides important infor-
mation, such as the manufacturer, content, nutritional value, or shelf life of
the food. It makes a significant contribution to ensuring food safety for
consumers.

Safe, non-hazardous food also requires safe packaging material. This
material is scrutinized by official food controllers to the same extent as
food itself. Whether plastic, wood, glass, ceramic, silicon, rubber or paper;
every material that comes into contact with food interacts with it. Especial-
ly the small, so-called low-molecular substances < 1000 Da can migrate
from packaging into food. This can occur via direct, wetting contact or
through the vaporization of volatile substances from the packaging that
recondense on the food (so-called gas phase transfer). An equilibrium
between the food and the packaging ensues, whose condition is deter-
mined by the speed of the molecular migration (kinetics) and the differ-
ence in concentration between the food and packaging (diffusion) [1].
Seite 3 von 9




                                      migration

                                     printing inks, varnishes, adhesives

                                     paperboard carton made of recycled paper

                                   inner bag

                              food stuff


Principle of Migration of Substances into Food. As example, a food product with an inner
plastic bag inside a paperboard carton made of recycled paper.


The degree of migration is determined by various factors:
      Type of chemical substance:
      Polarity, i.e. whether the substance is more hydrophilic („water-
      loving“) or lipophilic („fat-loving“);
      Molecular weight and steric requirements: the less space the mol-
      ecule needs, the more mobile it is;
      Vapor pressure: this is dependent on the chemical structure; the
      higher it is, the faster the molecules vaporize and redeposit them-
      selves on the food.
      Type of food: fatty foods, e.g. lipophilic („fat-loving“, non-polar) ab-
      sorb molecules more easily than watery foods.
      Duration of contact between the food and packaging: the longer
      the contact, the more substances that migrate into the food.
      Temperature during the filling and storage of the packaging: the
      warmer the surroundings, the faster the molecules move, and the
      faster the equilibrium is achieved, thereby causing their migration
      into the food.

Therefore, it is necessary to know exactly what the packaging material is
made of in order to choose the material most protective for a specific food
and under what conditions the least amount of migration will occur. Of
course, one must also know exactly which unwanted substances with po-
tential risk of migration the packaging contains, in order to gauge and ana-
lyze their behavior upon contact with the food (analysis of migration).



The Genesis of Recycled Paper Projects
Substances can also migrate from recycled food packaging paper into
food. Well-known cases from the past include diisopropylnaphthaline
(DiPN) or diisobutylphthalate [2]. Lawmakers enacted specific measures
to regulate the passage of these unwanted substances.

The sources of contamination that find their way into the recycling cycle
are varied: low-molecular chemicals migrate from, e.g., printing inks, ad-
hesives or production aids, into paper pulp, then into the recycled paper
and paperboard cartons made for food contact.

However, it is still a long road toward identifying all these different sub-
stances, evaluating their risk for human health, and then enacting regula-
Seite 4 von 9




tion. EU Regulation Nr. 1935/2004 stipulates that no food contact material
substance may migrate into food in a quantity that proves harmful to one’s
health or that changes the food in an unacceptable way. To test whether
this law is also kept for food packaging made of recycled paper, the Fed-
eral Ministry of Food, Agriculture and Consumer Protection (BMELV)
(www.bmelv.de) called for a „decision support“ project. From 2010 to
2012 a joint study was conducted by CVUA Stuttgart, Kantonales Labor
Zürich (www.klzh.ch), Landesuntersuchungsanstalt Sachsen Dresden
(www.lua-sachsen.de)        and     Technische     Universität   Dresden
(http://www.chm.tu-dresden.de/lc2/).




On the basis of the results, the BMELV is now investigating the need for
action regarding risk management, enforcement measures and/or specific
legal provisions for food packaging made with recycled paper.

Goals of the Recycled Paper Project
Using a systematic approach to the recycled paper project, the following
questions were to be answered:
       Which chemical substances are present in food packaging made
       from recycled paper?
       Is there a main source of entry in the paper cycle, so that a differ-
       ent choice of raw materials could reduce the amount of unwanted
       substances in the end product?
       Is there a timing and regional difference in the assembly of the un-
       processed food cartons?
       Which substances migrate from recycled cartons into food?
       What is the situation regarding contamination of food on the mar-
       ket?
       What possibilities exist to hinder the contamination of food from re-
       cycled paperboard packaging?



Most Important Insights from the Recycled Paper Project
Several problematic and therefore unwanted substances in recycled paper
were already known before the beginning of the project. Thus, specific
quantitative analyses were conducted on the project samples (raw materi-
al, pulp, unprocessed cardboard) in terms of the following substances:
mineral oil hydrocarbons ((mineral oil saturated hydrocarbons (MOSH),
mineral oil aromatic hydrocarbons (MOAH)), polycyclic aromatic hydro-
carbons (PAK), diisopropyl-naphthalene, softeners (e.g. phthalate), printer
ink ingredients (e.g. photo initiators, acrylate), pigment contaminants (e.g.
primary aromatic amines), ingredients of thermo paper (bisphenol A/S, 2-
phenylmethoxynaphthalene, 4-benzylbiphenyl), optical brighteners (stil-
bene derivatives), metabolites (e.g. diethylhexylmaleate), preservatives
(e.g. isothiazolinone, benzoic acid) as well as inorganic ingredients. Com-
prehensive and elaborate screening analyses were carried out in order to
identify further potentially migratory substances.
Seite 5 von 9




Investigations into Raw Materials Used in the Recycling of Scrap Pa-
per




                  Scrap paper as raw material for paper recycling.


Raw material used for the recycling of newspapers, magazines, adver-
tisement fliers, brochures, and special papers such as thermo paper or
glued products such as cartons have different quantities of unwanted sub-
stances and, therefore, different levels of contamination. Newspapers are
the most common source of mineral oil (MOSH < C24 to approx.
8,000 mg/kg; MOAH to approx. 1,600 mg/kg), sticky cartons for softeners
(total phthalate here approx. 35 mg/kg), thermo paper for BPA derivatives
or 2-Phenylmethoxynaphthalene (each over 10 g/kg), and magazines for
certain printing ink ingredients like photo initiators.

None of the sufficiently available, quality grade recycled paper is com-
pletely free of potentially migratory substances. A better choice and grade
of raw materials that would avoid the contamination of recycled paper-
boards with unwanted substances, therefore, is out of the question.



Comprehensive Analysis of Recycled Cartons
The attempt of a comprehensive analysis of recycled paperboard cartons
regarding the myriad, sufficiently volatile and potentially migratory sub-
stances therein by means of complex analytical methods and instruments
such as the LC-GC, GC-MS und GC x GC-MS, revealed over 250 sub-
stances with quantities above 100 µg/kg in the cartons. About 2/3 of these
were identifiable via mass spectrometry (see illustration). Quantities
greater than 100 µg/kg per carton could lead to a migration in food of more
than 10 µg/kg – a limit that is often given as a tolerance level for unevalu-
ated substances. The analysis was not so concerned with wood-
containing substances, but rather focused mainly on chemicals that come
along with recycled paper and carton raw materials, as was shown by
comparison of analysis of recycled paper boards boards made of virgin
fibers. Fortunately, no previously unknown migratory substances in con-
centrations above 10 mg/kg in recycled boxes were identified. Because of
the constantly changing technology of non-food papers due to the use of
printing inks, varnishes, coatings, etc. one cannot guarantee comprehen-
sive controls of recycled packaging at every point of production. Over a
two-year period no significant difference in terms of timing or region was
found between the product samples of four different German recycling
factories.
Seite 6 von 9




Two-dimensional gas chromatography (GC x GC) representation of a recycled food pack-
aging box: every shadow corresponds to an organic substance. The darker the spot, the
higher the concentration in the box.




Review of the Recycling Process




Deinking sludge from a flotation for the separation of printer inks in the recycling process

A random sample investigation of the recycling process (see also “How
my      Cornflakes   Box      is    Created    from      Recycled     Paper”
http://www.cvuas.de/pub/beitrag.asp?subid=1&ID=1683&Thema_ID=3&la
ng=DE) showed a slight trend toward the depletion of substances via the
deinking or drying process (e.g. for specific phthalate or bisphenol A).
However, these effects are not significant enough to ensure a completely
safe recycled box, especially in terms of a reduction of mineral oil.
Seite 7 von 9




Investigation Into the Storage of Food in Recycled Cartons




Left: unprinted recycled cardboard for warehouse investigation. Right: rice in polypropylene
trays, wrapped in polyethylene plastic wrap for storage in the recycled cardboard boxes
pictured on the left.

Controlled storage investigations were made regarding the presence of
potentially migratory substances in food samples from unprinted recycled
paperboard boxes at 2, 4, and 9 months. It was found that mineral oil,
phthalates, diisoprophylnaphthalines and photo initiators such as benzo-
phenone had migrated from the recycled cartons into the food. The
amount of butylphthalate detected in the food was greater than the total
migration limit stipulated by the 36th BfR (Federal Institute for Risk As-
sessment) recommendation for butylphthalate [4] in paper and cardboard.
Dibutylphthalate is categorized as being toxic to reproduction [5], and
diisobutylphthalate is a fertility-endangering substance (categorie 1B) [6].
The amount of the controversial mineral oil [7] rose to as high as 52 mg/kg
MOSH and the possibly carcinogenic aromatic hydrocarbons (MOAH) to
9.4 mg/kg. Depending on the type of plastic inserted between the carton
and food, there were either no (polyethylene), little (polypropylene) or
good (polyethylenterephthalate) properties of barrier protection against
migration from the recycled cartons.


Investigations of 119 Cardboard-packaged Foods from Retail
In 2010, 119 samples of food in cardboard packaging were collected from
various German retailers and stored until the end of their shelf life [9,10].
Examinations revealed marked contamination with saturated (MOSH)
and aromatic mineral oils (MOAH) whose toxicological valuations differ by
molecular weight and chemical structure and which, due to missing toxico-
logical data, cannot yet be clarified. Especially worrying is the presence of
aromatic mineral oils MOAH, which could possibly contain carcinogenic
substances [7, 8]. The amount found in food reached values of up to
100 mg/kg MOSH (median value, 17 mg/kg) and 16 mg/kg MOAH (medi-
an value, 3.0 mg/kg). In addition, the food samples were found to contain
the softener butylphthalate (the quantity detected in approx. ¼ of the food
in recycled cartons was greater than the limit value of 0.3 mg/kg [4]) set by
the 36th BfR recommendation for paper and cardboard) and printer ink
ingredients (photo initiators, mainly benzophenone up to 340 µg/kg). For
the food taken from individual retailers, however, it is not possible to de-
termine whether the source of the detected contamination is from the re-
cycled cartons or from another source.
Seite 8 von 9




Summary of the Recycled Paper Project
The comprehensive analysis of recycled paper cartons uncovered more
than 250 substances in quantities of over 100 µg/kg that were sufficiently
volatile for a potential migration into food. Monitoring these substances is
neither possible nor economical [11]. The quantity of potentially migrating
substances in recycled cartons cannot be reduced either by choosing
higher quality raw material paper - which is not available in adequate
quantities - or by changing the recycling process itself to an extent that the
safety of products can always be guaranteed. Changes in other non-food
technologies risk the introduction of new contaminants. From the view of
the project participants, a solution needs to be found where such migration
could be reduced by a factor of 100. The use of appropriate plastics as
barriers (e.g. inner bags or layering of the carton) could help. Various ma-
terials could be appropriate here. However, it is necessary to conduct reli-
able tests on these barrier materials in order to ensure the safety of food
and thus the protection of consumers from unwanted substances.



References
[1]       Tehrany, E.A. and S. Desobry, Partition            coefficients in
          food/packaging systems: a review. Food             Additives and
          Contaminants, 2004. 21(12): S. 1186-1202.

[2]       Brauer, B. and T. Funke, Bestimmung von Kontaminanten - Papier
          aus recycelten Fasern und verpackten Lebensmitteln. Deutsche
          Lebensmittel-Rundschau, 2008. 104(7): S. 330-335.

[3]       Bundesverband der Deutschen Entsorgungswirtschaft, Altpapier -
          Liste der europäischen Standardsorten und ihre Qualitäten. 2000.
          2000: S. 1-25.

[4]       BfR, XXXVI. Empfehlung Papiere, Kartons und Pappen für den
          Lebensmittelkontakt. BfR Empfehlungen, 2012. 01.01.2012.

[5]      ECHA, European Chemicals Agency, Evaluation of new scientific
         evidence concerning the restrictions contained in Annex XVII to
         Regulation (EC) No. 1907/2006 (REACH), Review of new available
         information for "dibutyl phthalate (DBP)", Review Report July 2010,
         im Internet unter http://echa.europa.eu/doc/reach/restrictions
         /dbp_echa_review_report_2010_6.pdf

[6]       VO (EG) 1907/2006: Verordnung (EG) Nr. 1907/2006 des Europä-
          ischen Parlaments und des Rates vom 18. Dezember 2006 zur
          Registrierung, Bewertung, Zulassung und Beschränkung chemi-
          scher Stoffe (REACH), zur Schaffung einer Europäischen Agentur
          für chemische Stoffe, zur Änderung der Richtlinie 1999/45/EG und
          zur Aufhebung der Verordnung (EWG) Nr. 793/93 des Rates, der
          Verordnung (EG) Nr. 1488/94 der Kommission, der Richtlinie
          76/769/EWG des Rates sowie der Richtlinien 91/155/EWG,
          93/67/EWG, 93/105/EG und 2000/21/EG der Kommission (ABl. L
          396/1), zuletzt geändert durch die Verordnung (EU) Nr. 412/2012
          vom 15. Mai 2012 (ABl. L 128/1).
Seite 9 von 9




[7]       EFSA, Scientific Opinion on Mineral Oil Hydrocarbons in Food.
          EFSA Journal, 2012. 2012(10(6):2704): p. 1-185.

[8]      http://www.bfr.bund.de/de/presseinformation/2012/41/
         mineraloele_in_schokolade_und_anderen_lebensmitteln_sind_
         unerwuenscht-132174.html, Presseinformation des Bundesinstituts
         für Risikobewertung 41/2012 vom 28.11.2012.

[9]       Vollmer, A., et al., Migration of mineral oil from printed paperboard
          into dry foods: survey of the German market. European Food
          Research and Technology, 2011. 232(1): p. 175-182.

[10]     Biedermann, M. et al., Migration of mineral oil from printed
         paperboard into dry foods: survey of the German market. Part II:
         advancement of migration during storage, European Food
         Research and Technology, DOI 10.1007/s00217-012-1909-2,
         2013.

[11]     Biedermann, M., Grob, K. Is comprehensive analysis of potentially
         relevant migrants from recycled paperboard into foods feasible?
         Journal of Chromatography A, 1272 (2013) 106– 115.




Photo credits:
Dr. Antje Harling




Author:
Dr. Antje Harling

								
To top