The mystery surrounding Phar Lap’s death in 1932 in Menlo Park, Calif., has finally been solved: scientists have confirmed that the horse died of arsenic poisoning. Researchers Dr. Ivan Kempson of the University of South Australia and Dermot Henry, manager of Natural Science Collections at Museum Victoria, took six hairs from Phar Lap’s mane and analyzed them at the Advanced Photon Source Synchrotron in Chicago, finding that in the 40 hours before Phar Lap’s death the horse had ingested a massive dose of arsenic.

Poisoning had long been suspected in the gelding’s death. His trainer found him suffering from a high fever and in severe pain. A few hours later, he hemorrhaged to death. During an autopsy, it was discovered that his stomach and intestines were inflamed.

Now the only question that remains is whether it was accidental — notebooks kept by Phar Lap’s handler Tommy Woodcock, obtained by Museum Victoria, show the horse was administered tonics and ointments containing both arsenic and strychnine — or intentional: some believe that U.S. gangsters had ordered his death because they feared that he would impact the winnings of their illegal bookmaking operations.

Certainly, the horse’s death has continued to pique interest. In 2000, a prominent veterinarian studied the autopsy reports and concluded the death was probably caused by Duodenitis-Proximal jejunitis, caused by a bacterial toxin. Since the disease, which matches the symptoms and autopsy results, was not identified until the 1980s, veterinarians would not have recognized it in 1932.

In 2006, Australian Synchrotron Research scientists said it was almost certain Phar Lap was poisoned with a large single dose of arsenic in the hours before he died. Another Australian scientist, Dr. Percy Sykes, disputed the theory because arsenic was quite commonly used in those days. He estimated that 90% of racehorses had arsenic in their systems.

Phar Lap was the “wonder horse” of Australia and New Zealand, winning 37 of 51 starts. At the time of his death, he was the third-highest winning stakes winner in the world. He had been shipped to North America to compete in its richest race, the Agua Caliente Handicap, in Tijuana, Mexico, which he won by two lengths.

Phar Lap is lucky that he didn’t race today, when top horses run only a handful of times and early speed is prized. Australian trainer Harry Telford convinced one of his owners to buy Phar Lap at auction in New Zealand base on his bloodlines. When the colt arrived in Australia, he was so unimpressive that the trainer agreed to train him for free, in exchange for 2/3 of his future winnings — if any!
Phar Lap came last in the first race he entered, and he did not place in his next three races, confirming the trainer’s expectations. He broke his Maiden in 1929 and later that year took second in the Chelmsford Stakes at Randwick. In 1930 he won the prestigious Melbourne Cup, and in 1931 his career took off: he won 14 races in a row.

The big chestnut gelding is still revered in Australia. There was a movie made of his career in 1983, his skeleton is on display at the Museum of New Zealand Te Papa Tonqarewa and his taxidermied hide is on display a the Melborne Museum.