Table 4.

Research Recommendations: Etiology

1.	Define the devices, and combinations thereof, associated with EVALI.
2.	A complete list of chemicals used by patients with EVALI should be made available to researchers such that rapid testing of top candidates can be done via in vitro and in vivo studies using available models, to identify mechanisms by which they may be causing injury. These studies should include human airway epithelial cell cytotoxicity and response to inflammatory stimuli, airway macrophage cytotoxicity and functional assays, and cytokine release that is tied with neutrophil recruitment to the lung.
3.	Define use behaviors of different products, including the latest THC delivery devices (dabbing, crackle, and waxing), and frequency and length of product use.
4.	Define combined pulmonary exposures (THC vaping plus conventional tobacco, etc.) and study each for evidence of interactions and even synergistic effects.

Definition of abbreviations: EVALI = e-cigarette or vaping product use–associated lung injury; THC = tetrahydrocannabinol.