A note on rengas poisoning
This note by W. C. Brown, M.D., documents the toxic properties of Rengas tree sap and its effects on workers in the Straits Settlements, with particular attention to the woodcutting trade in Penang (p. 83).
Summary
Brown describes the Rengas sap as a violent irritant that produces pustular eruptions on contact with skin, and a dangerous internal poison causing vomiting and purging. He notes that the wood retains its irritant properties even after years of seasoning, which seriously impairs its economic value for cabinet-making (p. 84). Treatment involves wrapping affected areas in bandages with dry alkaline powder such as bicarbonate of soda, while vaseline or lard serves as a preventive barrier for woodcutters. Neglected cases, particularly in emaciated subjects, tend to develop into chronic ulceration between the fingers and toes (p. 84).
Brown also records Malay beliefs surrounding the tree, including claims that exhalations from a felled stem cause facial swelling, fever, and blindness, and that elaborate exorcisms against djins and langsyar render woodcutters immune to the sap. On investigation, he found that the so-called “adepts” at Ayer Etam in Penang were in fact simply protecting themselves with coco-nut oil (p. 85).