Science, Tech, Math › Science Resiniferatoxin Is 1,000 Times Hotter Than Pure Hot Pepper Heat It's the hottest chemical known to science Share Flipboard Email Print DEA / C. SAPPA / Getty Images Science Chemistry Basics Chemical Laws Molecules Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. our editorial process Facebook Facebook Twitter Twitter Anne Marie Helmenstine, Ph.D. Updated January 13, 2019 The hottest hot pepper is no match for the spicy heat of the resin spurge Euphorbia resinifera, a cactus-like plant native to Morocco. The resin spurge produces a chemical called resiniferatoxin, or RTX, which is a thousand times hotter on the Scoville scale than pure capsaicin, the chemical that produces heat in hot peppers. Law enforcement-grade pepper spray and the hottest hot pepper, the Trinidad Moruga Scorpion, both pack a punch of about 1.6 million Scoville heat units. Pure capsaicin comes in at 16 million Scoville units, while pure resiniferatoxin has 16 billion—yes, billion—Scoville heat units. Both the capsaicin from hot peppers and the resiniferatoxin from the Euphorbia can give you chemical burns or even kill you. Resiniferatoxin makes the plasma membrane of sensory neurons permeable to cations, especially calcium. Initial exposure to resiniferatoxin acts as a strong irritant, followed by analgesia. Even though the chemicals may be painfully hot, both capsaicin and resiniferatoxin can be used for pain relief.