Alice Ball invented a method to transform chaulmoogra oil into an injectable treatment for leprosy, making it the most effective therapy for the disease for over two decades. Known as the Ball Method, her technique solved a problem that had stumped doctors for years: how to get a promising but stubbornly oily plant extract to actually work inside the human body. She accomplished this at age 23, while working as a chemistry instructor at the College of Hawaii in 1915.
The Problem With Chaulmoogra Oil
Chaulmoogra oil, pressed from the seeds of a tropical tree, had been used in traditional medicine across South and Southeast Asia for centuries. By the early 1900s, Western doctors recognized it as one of the only substances that seemed to help people with leprosy, a bacterial infection that causes severe skin lesions, nerve damage, and disfigurement. But getting the oil into patients effectively was a nightmare.
Swallowing the oil was the simplest approach, but effective doses made patients violently nauseous. Treatment was essentially limited by how much a person’s stomach could tolerate, which often wasn’t enough to do much good. When doctors in the 1890s started trying injections instead, the nausea went away, but new problems appeared. The thick oil wasn’t absorbed well by the body, and injections produced severe local reactions, fevers, and agonizing abscesses at the injection site. One patient later described being hospitalized multiple times with painful, pus-filled ulcers caused by the injections. The oil’s fatty acids simply weren’t compatible with the water-based chemistry of human tissue.
How the Ball Method Worked
Ball’s breakthrough was a chemical process that converted the fatty acids in chaulmoogra oil into a water-soluble form the body could actually absorb. She used a technique called esterification, reacting the oil’s fatty acids with an alcohol under controlled laboratory conditions to produce compounds called ethyl esters. These modified molecules contained additional oxygen atoms that changed their chemical behavior, making them polar (attracted to water) instead of stubbornly oily.
The result was a preparation that could be injected without the brutal side effects of raw chaulmoogra oil. Because the body could absorb the modified compounds, the treatment was far more effective. Patients at the Kalihi Hospital leprosy ward in Honolulu began receiving injections based on Ball’s method, and some improved enough to be released.
The Ball Method remained the preferred treatment for leprosy worldwide until the 1940s, when a new class of antibiotics called sulfone drugs replaced it. For roughly 25 years, Ball’s chemistry was the best option available for people with one of history’s most feared diseases.
Ball’s Path to the Discovery
Alice Augusta Ball was born in Seattle in 1892. She earned a bachelor’s degree in pharmaceutical chemistry from the University of Washington, then moved to Hawaii for graduate school. At the College of Hawaii (now the University of Hawaii at Manoa), she researched the chemical properties of the kava plant for her master’s thesis, studying the active compounds in the species Piper methysticum. She completed her degree in 1915, becoming the first African American and first woman to earn a master’s in chemistry from the university.
Her skill in plant chemistry caught the attention of Dr. Harry T. Hollmann, a physician at Kalihi Hospital who had been struggling with the chaulmoogra oil problem. He asked Ball to investigate whether she could chemically modify the oil into something usable. She was just 23 when she developed the method, and the university hired her as its first female chemistry instructor.
Stolen Credit and Belated Recognition
Ball never published her findings. She became ill and died on December 31, 1916, at age 24. The cause of her death remains unclear. Without Ball alive to claim her work, Arthur Dean, the president of the College of Hawaii’s chemistry department and a Yale-trained chemist, continued developing her research and published the results under his own name. He called it the Dean Method.
Hollmann, the physician who had originally brought Ball into the project, pushed back. In a 1922 paper published in the journal Archives of Dermatology and Syphilology, he publicly credited Ball as the true originator of the technique and coined the term “the Ball Method.” But Hollmann’s correction didn’t gain much traction during his lifetime, and Ball’s contribution was largely forgotten for decades.
Recognition came slowly. In 2000, the governor of Hawaii proclaimed February 29 as Alice Ball Day. In 2022, Governor David Ige signed a new proclamation moving the date to February 28 so it could be observed every year rather than only during leap years. The University of Hawaii has placed a plaque near a chaulmoogra tree on its Manoa campus in her honor, and the American Chemical Society has designated her work as a national historic chemical landmark.