Leading ink manufacturers in Europe like Sun Chemical, Flint Group and Siegwerk, together with many medium and small producers, have been continuing their development work on increasing the safety of inks for food packaging. They have been stepping up their efforts to ensure their low-migration inks meet the quality standards of conventional inks.
Some of them are also tackling new safety concerns, such as hazardous by-products from UV curing, which can pass through the packaging materials into foodstuffs.
Measures have also been taken by some ink makers to deal with worries about the components of non-packaging inks threatening the safety of recovered papers used in packaging. Despite de-inking treatment during paper recycling, mineral oils from publication inks which could be hazardous to human health are migrating from carton board into packaged food.
However, a major challenge for ink companies that have been investing heavily in the development of low-migration inks and safer inks in general is an apparent indifference among a large proportion of European food packaging converters to the possible dangers of certain chemicals in conventional inks. They are not acknowledging the need to use safer inks whose chemicals are highly unlikely to move through the packaging material into food products.
Furthermore, most regulatory authorities are not exerting much pressure on converters and printers. Many of them are downplaying public fears about the hazards of chemicals from printing inks and packaging materials, such as mineral oils, entering into foodstuffs.
There is still no European Union regulation focusing on controls of printing inks in food packaging by, for example, setting specific migration limits (SMLs) on ink components and mineral oils.
Instead, general requirements have been made by a 2004 EU regulation covering packaging materials, including printing inks and mineral oils. This stipulates that “under normal and foreseeable conditions of use,” the components of packaging materials must not move into food at levels which would endanger human health; bring about an “unacceptable” change in the composition of food; or cause a deterioration in the organoleptic characteristics – texture, taste, aroma – of the food.
The only European regulation applying specifically to food packaging inks is a national ordinance on food contact materials in Switzerland, a non-EU country, which came into effect three years ago. It sets out a positive list of chemicals which can be used in packaging inks with SMLs.
With the absence of specific regulations elsewhere in the region, the Swiss ordinance has been adopted as an international standard by some brand owners for application in their packaging supply chains. The German government has been working on a similar draft ordinance, which once approved, may be used in a similar way by international food companies.
Some multinational brand owners are laying down detailed specifications to packaging suppliers to curb the dangers of migration. But generally, most European food companies are not yet requiring packaging converters to use low migration inks, although a growing number are demanding that they use virgin instead of recycled paper and board.
Supermarkets, most of which operate nationally, appear reluctant to make specific requirements on packaging producers. Possibly, this is because they contract out the manufacturing of their own branded food products, so that in the event of a dangerous migration incident, they believe they would be exempt from legal liability.
“We are finding that supermarkets will not lay down specifications for food packaging such as the use of low-migration inks,” said Paul Regan, technical director at the UK subsidiary of Zeller+Gmelin, the German ink maker which showed at the international Drupa printing exhibition at Dusseldorf, Germany, a full comprehensive low-migration range.
“The great majority of food packing companies in the UK are still using standard inks, and the demand for low-migration inks is growing only slowly,” Mr. Regan continued. “We have warned our customers that the use of standard inks runs a risk of producing non-compliant packaging which would result in expensive product recalls.”
Lack of interest by supermarket chains is considered to be one of a number of reasons for weak demand for low-migration inks in countries like the UK. Another is the higher prices for the inks – as much as 30% more than conventional ones. Converters are also worried about the expense of setting up separate production lines for low migration printing.
Among UK converters who print packaging labels, less than 1% are currently using low-migration inks, according to estimates by the British Printing Industries Federation (BPIF). This compares with proportion of a quarter to a third in countries such as Germany.
“Among label printers, the primary reason for the poor demand is ignorance,” said John Bambery, chairman of BPIF Labels, which represents label printers. “They don’t realize that there’s a danger of chemicals from standard inks on labels migrating through the packaging into food products. Once they become aware that there is a problem with the conventional inks, they may take a different attitude to low-migration inks.”
BPIF Labels has already distributed among label printers a brochure on the issue of migration. It is now publishing a 55-page guide to Good Manufacturing Practice (GMP) in the production of food packaging labels, with an emphasis on ways to avoid migration problems.
“We’re warning the printers that future health scares about incidents of contamination of packaged food due to migration could have an impact on their businesses,” said Mr. Bambery. “GMP involves making risk assessments of possible migration problems with food packaging jobs so that printers can show they are complying at least with the EU 2004 regulation. They will then not have to worry about the effects of health scares.”
The latest migration scare in Europe stemmed from a study late last year by the German consumer organization Stiftung Warentest of chocolates in Xmas Advent calendars. It found that chocolates in 24 calendars it tested had been tainted with mineral oils presumed to have come from the cardboard packaging.
The calendars were re-examined by the paper technology and mechanical engineering unit of Darmstadt Technical University in Germany, which found that 23 out of 24 of them were made from virgin fiber. Instead, the source of the mineral oils was considered to be packaging materials and printing inks, and/or additives or chemicals used in the production of the chocolates.
The case has highlighted the increasing use in Europe of virgin fiber in paper and board packaging because of fears that de-inking processes in paper recycling are not eliminating all potentially hazardous traces of mineral oils.
It also reinforced the view that regulatory organizations are not getting anxious about migration incidents. After studying the evidence from the tests of the Advent calendars, the German Federal Institute for Risk Assessment (BfR) concluded that only a “very low additional quantity” of aromatic mineral oils, which are the most dangerous of the oils, would have been consumed daily.
In a survey conducted around a year ago, the UK Food Standards Agency (FSA) found that out of 350 samples of packaged food tested, 84, or 24%, contained printing ink components. The photoinitiator benzophenone, which has been considered to be a potential hazard to health since the early 2000s, was detected in 37, or 11%.
In an analysis of samples of carton-board packaging among the 350 samples, all had one or more mineral oils present.
After a risk assessment of its findings, the FSA concluded that it did not raise any specific safety concerns. “There is no need for consumers to change their eating habits to food that has been packaged in virgin or recycled carton-board,” it said.
The agency complained about the limited toxicological data available on many of the substances covered in the survey. With mineral oils, it explained that the lack of toxicological data on many of them meant there was “uncertainty in assessing the risk to consumers from the results of this study.”
In a study of mineral oils in foods, the European Food Safety Authority (EFSA), the EU’s main food safety agency, also stressed the uncertainties about the chemical composition of the oil and as a result their impact on human health. It recommended that more data should be collected for analysis and monitoring to make proper risk assessments.
Mineral oils “comprise a diverse group of mixtures of hydrocarbons containing thousands of chemical compounds of different structures and size, derived mainly from crude oil but also produced synthetically from coal, natural gas and biomass,” EFSA said. “The chemical composition of most (mineral oil) mixtures is unknown and usually varies from batch to batch.”
Printing inks are only one among a number of sources of the oils in packaging, with others being the packaging material, particularly carton-board, food additives, food processing aids and lubricants, it pointed out.
Meanwhile, ink producers are having to respond to new concerns about migrating substances in packaging inks, which previously had not been recognized as being potentially dangerous to health. These include chemicals formed in the inks during UV curing, which can trigger reactions creating by-products.
“UV curing is producing chemicals as by-products which were not in the original ink formulation,” said Steve Millen, head of the technical department at Mirage Inks, Radstock, England. “These by-products can differ depending on the components of the formulation. We try to ensure that our low-migration inks do not produce potentially hazardous by-products. It does mean additional development work and testing but it reinforces the safety of our inks.”
As research into the hazards of chemicals used in food packaging printing inks and materials intensifies over the next several years, new dangers to the public will be highlighted. But it looks likely that the ink companies in Europe that have been specializing in the development of safe packaging inks will be able to respond quickly to these new risks.
European Editor Sean Milmo is an Essex, UK-based writer specializing in coverage of the chemical industry.