From a poison to a patent medicine: arsenic in Hong Kong

Abstract

Arsenic has an intriguing relationship with Hong Kong. In 1857, just months after the Second Opium War, arsenic was applied to breads for poisoning the European residents on the island. The so-called Esing poisoning case or the Esing Bakery incident might be a sore point among the expatriate community, but the Hong Kong Chinese had employed arsenic compounds as remedies for a long time. In the first half of the twentieth century, Hong Kong’s medical practitioners adopted arsenic trioxide as the standard anti-leukemic treatment before the introduction of chemotherapy in the 1950s. Although the advent of alkylating chemotherapeutic agents replaced arsenic trioxide for a while, the curative efficacy of arsenic trioxide and the undesirable side-effects of chemotherapy triggered a renewed interest in the remedial promise of the former. Intravenous arsenic trioxide emerged as a drug therapy for treating acute promyelocytic leukemia and oral arsenic trioxide has become a locally produced and patented prescription drug in Hong Kong since 2000. By exploring the vicissitudes of arsenic in Hong Kong, this paper intends to examine ways in which the history of arsenic is intertwined with the colonial and postcolonial history of Hong Kong. The dual toxic and therapeutic effects of arsenic has been recognized in the West in the sixteenth century by Paracelsus who suggested “all things are poisons in the right doses” while the medicinal use of arsenic dated back to Hippocrates in ancient Greece. In pre-modern China, the use of poison to cure sickness was so widespread that led Yan Liu, a historian of science at Harvard University, to draw the conclusion that “Healing in traditional China, then, was inconceivable without poisons.” My interest in the current paper is not to dwell on the dichotomy between toxin and medicine; rather, my aim is to connect the recent pharmaceutical development of arsenic with the recovery of China’s medical heritage on medicinal poisons by examining how the emergence of arsenic therapeutics was informed by a re-imagination of China’s medical traditions coupled with modern Western medical practice.