Methamphetamine smoke: An emerging environmental health challenge

Smoking methamphetamine (MA) creates a potential risk of environmental (second-hand) exposure to others. Despite the public health concerns, essentially no data are available on the health effects of smoked MA. Using a unique rodent inhalation exposure system, our laboratory has previously published that acute inhalation of relevant doses of MA vapor is associated with significant injury in the lungs of mice.

The purpose of this study was to determine if MA is directly toxic to lung epithelial cells and whether other components in the MA smoke contribute to this toxicity. We also sought to characterize MA smoke to find previously unidentified compounds in the MA smoke that may contribute to the toxic effects of MA. We hypothesized that MA smoke contains compounds that contribute to MA toxicity in lung epithelial cells.

In vitro studies were conducted utilizing mouse lung epithelial cells to determine toxicity of compounds by LDH release. Fourier Transform Infrared Spectroscopy, Aerosol Mass Spectrometry, and Ultra-high Sensitivity Aerosol Spectrometry were employed to measure trace gases, major smoke constituents, and aerosol contribution to MA emissions.

MA was not directly toxic to mouse lung epithelial cells. However, the MA pyrolysis product trans-phenylpropylene oxide dose-dependently caused cell death. When heated, MA vaporized into very small particles that likely are able to deeply penetrate the lung. In addition, we found unidentified components of MA smoke that will be characterized in future studies.

We conclude that environmental exposure to MA smoke may present a potential health concern and that further studies are warranted.