Mineral-Oil Residues in Food: TÜV SÜD

11-08-2017

The acronyms MOSH & MOAH refer to mineral-oil components that enter into our food and environment through various pathways. While consumers can do very little to prevent MOSH and MOAH residues, the food industry has responded by introducing minimisation strategies. TÜV SÜD's food experts explain the current measures that strengthen preventive consumer protection.

Not only mineral oil itself but also its individual components can be detected in food products. MOSH and MOAH residues can be found in both raw products and convenience food. The likely pathways by which they can get into food are many and varied. 

MOSH and MOAH stand for the chemical groups of saturated mineral-oil hydrocarbons and mineral-oil aromatic hydrocarbons. Next to unsaturated hydrocarbons, MOSH and MOAH are the main components of mineral oil. Mineral oil and its derivatives are common in printing inks used in newspaper printing or the print on packaging materials. From there the MOSH and MOAH compounds find their way into recycled materials. In addition to the above, mineral-oil fractions for example in lubricants, used in the food and packaging industry, or in exhaust gases and consumables needed for the operation of harvesting machinery, get into food products.

As mineral oil and its components are used in a wide-range of applications, MOSH and MOAH are quite common.

Nevertheless, in food products their residues are definitely undesirable. Animal studies have shown that these substances pose potential health hazards. However, as the available studies in humans are inadequate and not considered significant by international standards, no upper limit has yet been defined for food products. Consequently, the migration of mineral-oil components to food products should be prevented as far as possible.

Organisations which learn that their products are contaminated by mineral-oil residues have various options to respond – all of them involving major efforts.

  • One possibility is to limit the use of recycled paper in food packaging, which has in fact recently been implemented. Packaging for food with large surface areas, such as rice, breadcrumbs or cereals, specifically, is increasingly made from virgin fibres.
  • Adhesives used in cardboard food boxes also include MOSH and MOAH which migrate directly into the food product. Additional PET film or specially coated inside bags may be a solution in these cases. They form a mechanical barrier, hindering the mineral-oil substances from migrating directly to the product. However, this solution is only open to dried food.
  • A third possibility is to change to printing inks free from mineral oil. This option helps to reduce the migration of mineral-oil residues to food and has been adopted by parts of the packaging industry, food industry and some food retailers. The success of MOSH and MOAH reduction measures also depends on further manufacturers of print products replacing the mineral oil in their products with vegetable oil.
  • To lead the MOSH and MOAH reduction measures to success, companies also need to be highly alert and must engage in a lot of specific residue analysis.

The problem of MOSH and MOAH residues in food products is a complex one. Consumers have little influence. Like with acrylamide, the reduction of MOSH and MOAH, i.e. a sustainable reduction of mineral-oil residues in food products, requires joint efforts from all industries involved (e.g. the printing ink industry, newspaper printing, paper industry, packaging industry, food packaging).