A Comprehensive Monograph on Petrolatum (CAS 8009-03-8): From Physicochemical Properties to Clinical and Cosmetic Applications

I. Executive Summary

Petrolatum is a complex, semi-solid mixture of hydrocarbons derived from petroleum, universally recognized for its exceptional occlusive and emollient properties. This monograph provides a comprehensive analysis of Petrolatum, identified by DrugBank ID DB11058 and CAS Number 8009-03-8, covering its chemical identity, manufacturing processes, mechanism of action, therapeutic and cosmetic applications, safety profile, and global regulatory status.

A central theme of this report is the paramount importance of the refining process in determining the quality and safety of the final product. The analysis establishes a clear distinction between highly refined cosmetic and pharmaceutical grades of Petrolatum, which are demonstrably safe for human use, and less-refined industrial grades that may pose health risks due to potential contamination with polycyclic aromatic hydrocarbons (PAHs). The safety, efficacy, and regulatory acceptance of Petrolatum are therefore entirely contingent on its purity.

In the United States, the Food and Drug Administration (FDA) approves Petrolatum as an over-the-counter (OTC) skin protectant, and it serves as a ubiquitous excipient and active ingredient in a vast array of dermatological, ophthalmic, and anorectal preparations. Concurrently, it is a cornerstone ingredient in the global cosmetics and personal care industry.

This report also details a significant paradigm shift in the scientific understanding of Petrolatum. Long considered a chemically inert barrier, recent clinical evidence reveals it possesses bioactive properties, actively modulating the skin's innate immune response and promoting the expression of key epidermal differentiation proteins. This modern understanding provides a molecular basis for its profound efficacy in treating barrier-deficient skin conditions.