Bombé, an undetermined substance that caused an outbreak of illicit drug use in Kinshasa, Democratic Republic of the Congo.

Background: Illegal drugs are becoming a public health problem in African cities. In 2021, Bombé, a new drug of unknown composition, caused an outbreak of neuro-psychiatric symptoms in Kinshasa. Bombé was rumored to be based on ground catalytic exhausts stolen from cars.

Methods: The chemical composition of six samples of Bombé obtained from different neighborhoods in Kinshasa was determined by triple quad liquid chromatography-mass spectrometry/mass spectrometry with confirmation by quadrupole time-of-flight mass spectrometry. Metals were determined by inductively coupled plasma-mass spectrometry, and polycyclic aromatic hydrocarbons were measured by gas chromatography-mass spectrometry.

Results: Analysis of the Bombé samples revealed that it contained heroin (2-12% of the total area under the curve of the samples) and opioid derivatives, plus paracetamol (33-72%), caffeine (17-26%), and also benzodiazepines (5/6 samples) and cyproheptadine (2/6 samples). The concentrations of neurotoxic metals were unremarkable. The median (range) concentrations of manganese and lead were 9.4 µg/g (range 3-334 μg/g) and 0.36 µg/g (range 0.1-3.12 μg/g ), respectively. All polycyclic aromatic hydrocarbons were below the level of detection (<0.10 µg/g).

Conclusion: Thanks to international collaboration, Bombé was documented to be a heroin-based drug and its alleged origin from catalytic exhausts was not substantiated. The local human expertise and technical capacity for undertaking toxicological analyses should be increased in Africa.