A new study on how often the migration limits were exceeded and reliable solutions.
June 10, 2014
by Canadian Packaging Staff
Bremen, Germany—Those who continue to rely on PVC seals for the metal vacuum closures see themselves confronted with an acute plasticizer problem as the PVC seals of a metal vacuum closure contain a proportion of between 20 and 40 percent plasticizer.
Plasticizers or dispersants are additives that increase the plasticity or fluidity of a material. The dominant applications—about 90 per cent—are for plastics, especially polyvinyl chloride (PVC), though it can also be used to improve concrete, clays, and related products.
Products containing a high proportion of oil are particularly affected by transfer of plasticizer into the food, since plasticizers are soluble in oil.
Sauces, fish products in oil, pickled vegetables or cheese in oil must therefore be considered particularly at risk.
The European Union (EU) has long set up and developed an extensive set of rules: but the numerous amendment guidelines, positive lists for additives and monomers, specified limit values for individual substances as well as the requisite extensive declarations of conformity represent a major challenge which is not ultimately complied with.
A study across Europe presented by the Cantonal Laboratory of Zürich and the Stuttgart Chemical and Veterinary Research Office found that a majority of the products exceeded the migration limit of 10 mg/dm² according to EU Regulation 10/2011.
The study shows that 30 percent of the glass jars with fat-containing contents exceeded this limit, with about 21 percent of the samples found to exceed the number significantly.
Only 10 percent of the products examined were under the limit.
In 40 cases ESPO was found, 23 cases showed DEHT with an excess of the limit.
ESPO (Epoxidized soybean oil) is a plasticizer used in polyvinyl chloride (PVC) plastics, and as a scavenger for hydrochloric acid liberated from PVC when the PVC undergoes heat treatment
DEHT (Di(ethylhexyl) terephthalate) is a colorless viscous liquid used for softening PVC plastics)
Even forbidden plasticizers were found in some of the examined products.
Despite the fact that there has been a reliable solution available for this quandary since 2011: the innovative Provalin sealant material, PVC, phthalate or other worrying plasticizers are excluded.
This has been confirmed by numerous long-term studies. Concentrating on PVC-free solutions also makes sense considering that not only the maximum limit has to be adhered to for global migration but also exactly defined specific migration limits referring to individual plasticizers listed in the regulation (EU) 10/2011 (PIM)—for example: ESBO, PAD, AMG, ATBC, DBS, DINCH, DOTP, Phthalate and DEHA. If, for example, some of these plasticizers contain a PVC material, the objective is not only to adhere to the respective limit value for the specific migration of individual plasticizers but also to observe the limit value for the sum of all specific migrations.
This is not only a regulatory feature, it can also prove to be an obstacle with a result as indicated in the study referred to above.
With Provalin it is possible to these poor results.
Provalin is a sealing material for glass jars which has been developed and patented by ACTEGA DS. The ACTEGA Coatings & Sealants Product Division develops and produces coatings and sealants for the packaging and graphic arts industries. These products lend an attractive appearance to materials such as paper, paper board, plastic and metal. They also provide clearly defined chemical and physical properties to the materials’ surface.
Provalin is a thermoplastic elastomer (TPE) which does not require any plasticizers and therefore displays extremely low-migration characteristics.
Long-term tests have shown that Provalin is safe and complies with the new EU and USFDA regulations.
This sealing compound is used in Pano Blue Seal closures powered by Provalin, with German food processor Feinkost Dittmann the first food manufacturer to launch it onto the market.
ACTEGA is the market leader in overprint varnishes and is the technological leader in the rapidly expanding sector of water-based sealants for flexible packaging. In this connection, ACTEGA products not only ensure that the packaging will look appealing, but also that the contents will remain fresh longer.
The company says its is the technological leader when it comes to water-based sealants for cans. These products are used to make seals between the contact surfaces, such as glass on metal (bottle closures) or metal on metal (can lids). They ensure that the contents and other substances such as CO² remain inside the packaging, and any contaminants remain outside.