Abstract: Objective: To study whether dimethyl fumarate was the right substance that caused the food poisoning in Kaiyuan and the determination of its amount. Method: Dimethyl fumarate was abstracted from samples with enthanol, then centrifugated, analyzed by gas chromatographic-mass spectrometric method. Result: A standard curve showing a direct ratio between the concentration and the peak area was obtained, r =0.9961(p<0.05). Dimethyl fumarate was detected in the three samples, as 0.26, 0.20 and 0.11mg/g respectively. Conclusion: It proved that dimethyl fumarate is the right substance that has caused the food poisoning. The method is precise and accurate. The preparation of sample is simple and the assay is quick. The method proves to be satisfactory in dealing with such emergencies.

Key words: dimethyl fumarate, gas chromatographic-mass spectrometric method, food poisoning