76 Proceedings Vol. 83, Number 1 CHEMICAL O F T H E Q UA R T E R Understanding Acetic Anhydride by LT NichoLas Remke Staff Engineer, Marine Safety Center U.S. Coast Guard What is it? Acetic anhydride is a clear, colorless liquid with a pun- gent smell of vinegar, it’s not-too-distant relative. Due to its low cost and effectiveness in acetylation, it has many industrial applications, but its flammable, corrosive, irri- tating properties make it a hazardous material regulated globally. For its role in the synthesis of illicit drugs, ace- tic anhydride is classified as DEA List II precursor and tracked by more than 28 exporting countries. How is it used? Industrial Use Acetic anhydride is primarily used throughout indus- try for converting cellulose from wood pulp to cellulose acetate which is a main ingredient in the production of yarns, plastics, photographic film, coatings, and cigarette filters. Drug Synthesis The pharmaceutical industry uses acetic anhydride to make acetylsalicylic acid, more commonly known as aspirin. On an illicit note, acetic anhydride can be used to process heroin, amphetamine, and methamphetamine. According to a 2024 report, the illicit trade of the chemical peaked in 2018 at almost 200,000 liters seized. Since then, seizures have been minimal due to the rise of synthetic opioids like fentanyl, the Taliban’s ban on opium culti- vation in Afghanistan, and the heroin market shifting to southeastern Asian countries with less tendency to report. Shipping Hazards Acetic anhydride’s corrosive and irritating effects pose significant safety hazards. Special requirements includ- ing vapor detection, chemical protective clothing, and increased ventilation are required for maritime carriage. What is the Coast Guard’s role? The Coast Guard enforces maritime transportation requirements for all hazardous materials in liquid bulk, including acetic anhydride. The Office of Design and Engineering Standards at Coast Guard Headquarters establishes and interprets domestic regulations, includ- ing hazardous cargo classifications. The Marine Safety Center’s Tank Vessel and Offshore Division conducts engineering plan review and creates individual certifi- cates detailing authorized cargoes. Upon completion of successful inspections, local Coast Guard inspectors issue the certificates as authorization for the vessels to operate while carrying liquid bulk cargoes. About the Author: LT Nicholas Remke is a staff engineer in the Marine Safety Center’s Tank Vessel and Offshore Division. A 2019 U.S. Coast Guard Academy graduate, he holds a bachelor’s in marine and environmental sciences and a master’s in chemical engineering from Northwestern University. This office may be contacted at [email protected]. References: CAMEO Chemicals, National Oceanic and Atmospheric Administration https://cameochemicals.noaa.gov/chemical/2276. Visited 20 October 2025 International Maritime Organization. (2020). International Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk. IMO International Narcotics Control Board. (2024). Precursors: chemicals and equipment frequently used in the illicit manufacture of narcotic drugs and psychotropic substanceshttps://www.incb.org/documents/PRECURSORS/ TECHNICAL_REPORTS/2024/E/PRE_Report_E.pdf PubChem, U.S. National Library of Medicine. https://pubchem.ncbi.nlm.nih. gov/compound/Acetic-Anhydride. Visited 20 October 2025 PubChem, U.S. National Library of Medicine. https://pubchem.ncbi.nlm.nih. gov/compound/Cellulose-Acetate. Visited 20 October 2025 United States of America. (2025). Title 21 Code of Federal Regulations: Food and Drugs, Part 1310 – Records and Reports of Listed Chemicals and Certain Machines; Importation and Exportation of Certain Machines. Office of the Federal Register United States of America. (2025). Title 46 Code of Federal Regulations: Shipping, Part 151 – Barges Carrying Bulk Liquid Hazardous Material Cargoes. Office of the Federal Register United States of America. (2012). Title 46 Code of Federal Regulations: Shipping, Part 153 – Ships Carrying Bulk Liquid, Liquefied Gas, or Compressed Gas Hazardous Materials. Office of the Federal Register
