Mineral oil is the collective name for a range of byproducts of crude oil processing and refining. These compounds are mixtures of different weights and grades of hydrocarbons containing between 15 and 40 carbon (C15 to C40) molecules. Mineral oils undergo further distillation to remove contaminants such as sulfur, lead, vanadium and more complex hydrocarbons such as benzene to produce cosmetic-grade, food-grade and pharmaceutical-grade mineral oils. The final products are colorless, odorless liquids or opaque waxes. They are commonly known as paraffin, liquid paraffin, white oil, petroleum jelly or waxes. They have numerous applications in medicine, cosmetics, food manufacture, scientific research, wood conditioning and machinery lubrication.
Drugs and health care products, including pharmaceutical-grade mineral oil, in the United States should adhere to specifications set by the United States Pharmacopeia (USP) standards agency. Manufacturers have to ensure that USP pharmaceutical-grade drugs and chemicals meet the specifications outlined in the most recent USP and National Formulary (NF) standards. The USP verifies that the drugs are tested to ensure compliance with regulations. Food-grade mineral oil can also hold a USP certification, but not all food-grade mineral oils adhere to USP standards.
Pharmaceutical-grade mineral oil is a drug product under Food and Drug Administration (FDA) regulations. FDA rules apply to the sites where the drug is formulated, manufactured and packaged. If mineral oil manufacturers claim that their products are USP, they should ensure that their production processes follow current Good Manufacturing Practice (cGMP) – a quality control system in the pharmaceutical industry — and that the products are tested for purity and potency. The FDA can make unannounced inspections to manufacturing sites.
Under FDA regulations, food grade mineral oils are approved for incidental contact with foods and beverages. These products should not exceed 10 parts per million in any food. The Dietary Supplementary Health and Education Act of 1994 stipulates that food-grade products, among them mineral oil, should be “safe.” Manufacturers, not the FDA, are responsible for a product’s safety.
Food-grade mineral oil with a scent additive is used as baby oil. Food-grade mineral oil lubricants for food machinery contain corrosion inhibitors, foam suppressants and anti-wear agents, even though they are authorized for contact with food. Pharmaceutical-grade mineral oil has to be free of all impurities under USP standards.