5 Questions with Heather Rice, Senior Chemist, Nestle Quality Assurance Center

1. What are Mineral Oil Hydrocarbons?

Mineral oil hydrocarbons (MOH) include a wide range of chemical compounds derived from refined petroleum products. MOH are divided into MOSH (Mineral Oil Saturated Hydrocarbons): open chain branched hydrocarbons with at least 10 carbon atoms; and MOAH (Mineral Oil Aromatic Hydrocarbons): hydrocarbons with mono or polyaromatic rings. It’s important to distinguish between the MOSH and MOAH fractions due to different potential health concerns associated with each.

2. What are the current uses of MOH? How do they enter the food chain?

MOH are widely used in many applications including cosmetics, lubricants, inks, jute batching and the electrical industry. Contamination can occur at all points of the food processing chain, including unintentionally at field level during harvesting and during transport to processing sites. They can also migrate from processing machinery lubrication and from packaging.

3. Why should we be concerned about MOH in food?

While scientific knowledge on toxicological risks of MOH is not fully characterized and still under debate, MOSH accumulation in the body may cause damage to the liver and lymph nodes, while MOAH are suspected genotoxic carcinogens at certain exposure levels. As with any new emerging hazard, food manufacturers should assess risk and integrate control measures to mitigate risk into their overall food safety plan.

4. How do we analyze for MOH?

NQAC Dublin uses LC-GC-FID with automated on-line sample epoxidation and aluminum oxide clean up. In this method, MOSH and MOAH fractions are separated by liquid chromatograph (LC) and then transferred to gas chromatograph (GC) to determine the distribution of MOSH and MOAH according to carbon chain length. Values are quantitated by internal standards with total values and chain length distributions reported.

5. Why is Mineral Oil analysis a challenge?

Certain oil types contain interference that can pose a challenge to accurate integration and reporting of MOSH and MOAH. Analysts must be familiar with interfering biogenic n-alkanes, such as Polyolefin Oligomeric Saturated Hydrocarbons (POSH) and Resin Oligomeric Saturated Hydrocarbons (ROSH), to determine if aluminum oxide treatment is necessary to remove interfering peaks. Additionally, improper sampling or storage may result in contamination.