鎵是元素週期表中屬3A族的過渡金屬，三甲基鎵(trimethylgallium)廣泛應用在半導體與光電產業製程中，對勞工構成潛在的健康危害。本文報告一例罕見的急性中毒，發生在某化工研究學生進行實驗的時候。由於有機金屬化學氣相沈積法的管路外洩，患者吸入三甲基鎵蒸氣而不自覺，暴露當日便感頭暈、疲乏、沒有食慾。第五日就診時症狀已緩解，實驗室檢查與胸部X光並無異常。個案的指導教授亦曾意外吸入三甲基鎵，發生類似的病症，凸顯校園科學實驗室的職業安全衛生問題。本文探討三甲基鎵與相關鎵化合物的理化特性、毒物學機轉；檢討物質安全資料表的正確性，並提供預防性建議。三甲基鎵在我國各科學園區的用量甚大，職業醫學與工業衛生人員宜對此類中毒有所瞭解，以保障勞工的安全健康。

Gallium is a transitional metal belonging to Group 3A in periodic table, while trimethylgallium finds extensive application in semi-conductor and optoelectronic industries, constituting thus a potential occupational hazard. We reported a rare case of acute trimethylgallium intoxication, which took place in laboratory setting in a graduate school. Caused by undetected tubing leakage in metal organic chemical vapor deposition process, the student inhaled trimethylgallium vapor without self-awareness. He felt dizzy, anorexic, and malaise soon afterwards, only to recover fully on the fifth day. Clinical examination was unremarkable by then. His professor had suffered from similar exposure previously. The two accidents exposed the insecurity in chemical safety in campus laboratories. This article addressed clinical manifestation, gallium compound properties, biochemical pathogenesis of acute intoxication, and the discrepancy with Material Safety Data Sheet. In view of the significance of gallium-associated industries in Taiwan, it is deemed appropriate to report the case for the sake of occupational health and safety.