The Waxes Category includes refined/finished waxes, slack wax and petrolatum, also referred to as waxes and related materials (WRM).The members of this category are complex petroleum substances containing hydrocarbons with carbon number ranges predominantly from C-20 to C-85 but may contain a small fraction of smaller hydrocarbons. Waxes are predominantly saturated paraffins which are solid or semisolid at ambient temperature. Refined or finished waxes are typically used in candles or, if adequately refined, as food-grade waxes. Slack waxes are usually the precursors to refined/finished waxes. Slack waxes are frequently produced by de-waxing lubricant base oils during production of the latter so both are derived from the same vacuum distillates. Slack waxes may be just an intermediate stream for production of refined waxes or slack waxes may be used in products such as fire logs and particle board. Petrolatum (also called petroleum jelly) usually refers to a combination of highly-refined mineral oil and refined microcrystalline wax. Petrolatum, however, can also refer to a cruder product which is similar to a slack wax with high oil content.
Waxes are separated from the lubricating oil basestocks by chilling or solvent extraction. The wax molecules may also be catalytically converted to isoparaffin structures by a process called catalytic dewaxing. Crude petrolatums, which are essentially slack waxes, may be derived from less refined feedstock streams or with less processing and may contain polycyclic aromatic compounds (PACs) or other contaminants. Petrolatum which is produced from feedstocks that have undergone extraction or hydrotreatment steps to thoroughly remove PACs and other impurities are referred to as severely refined petrolatum, food or pharmaceutical grade petrolatum, or petroleum jelly. Highly refined petrolatum is used for food, cosmetic and pharmaceutical applications. The soft consistency of petrolatum is due to a gel-like dispersion of mineral oil in a paraffin or microcrystalline wax base.
To meet the HPV Challenge, the Testing Group has thoroughly evaluated the substances within the Waxes category and has made all of the reliable human health and ecological hazard data available to the public. In addition to evaluating hazard studies for the individual substances within this category, the Testing Group also assessed the toxicity of WRM using read-across from data with lubricating oil basestocks. The saturated hydrocarbons in WRM are similar to those in lubricant base oils and are derived from the same streams.