The EcigAero Aerosol Exposure Apparatus (patent pending) provides an important tool for studying the acute effects of vaping electronic cigarettes (E-Cigs) and the chronic effects of multiple E-Cigarettes a day for long periods of time by repeatedly exposing rodents to E-Cig aerosol in a home cage-like environment. Our system provides a powerful toolkit for in vivo studies of E-Cig effects on cardiovascular, respiratory and nervous systems, metabolism and carcinogenesis as well as facilitating new therapeutic discovery. E-Cig addiction studies will have important implications in nicotine replacement therapy (NRT) for smoking cessation.
As electronic cigarettes are a relatively new product, studies are needed to determine their long-term detrimental effects. E-Cigs may contribute to nicotine addiction and are unlikely to discourage conventional cigarette smoking among youths. Thus, E-Cigs could generate a new market for nicotine dependence.
E-Cigs generate aerosol, not simple nicotine vapor as incorrectly claimed by the E-Cig industry. Mainstream and second-hand E-Cig aerosols not only contain nicotine and propylene glycol and/or glycerin, but also detectable levels of toxins including carcinogens and heavy metals such as formaldehyde, benzene, nitrosamines, cadmium and lead. Therefore health risk and toxicology studies on animal models exposed to E-Cig aerosol, not limited to nicotine, are urgently needed.
In order for drug abuse studies with animal models to be relevant to humans, it is necessary that the routes of drug administration, the physical properties (vapor or aerosol) the pharmacokinetics (PK) and target tissue concentrations of the drug are comparable between humans and animals.
Direct delivery for ideal aerosol
No tubing, bends, mixing chambers, fans, or pumps between the ECig and the rodent chamber. Aerosols deteriorate rapidly during transport and dilution when passing through tubing and chambers due to droplet coagulation, condensation and vaporization. We have characterized the particle size distribution of the ECig aerosol in our chamber†. The EcigAero maintains consistent aerosol characteristics to those at the mouthpiece where humans inhale ECig aerosol. The pulmonary distribution of the aerosol generated in this device correlates with that generated by ECigs during typical human use.
Multiple “real” electronic cigarettes
The EcigAero will accommodate up to (4) four:
- First generation blu PLUS+ E-Cig (battery powered)
- Second generation JUULpods or myblu Liquidpods
- Third generation “mod” tanks with universal “510” industry-standard threads
- Can be used along with any aerosol via nebulizer (optional)
The aerosols are delivered at a highly regulated pressure with a flow rate between 0 and 4 liters per minute (LPM). Pods and tanks are precisely energized with 0.01V accuracy. The EcigAero tests the inhalation exposure of REAL ECigs rather than de novo generated mixtures of nicotine + E-liquid. The exposure doses of our rodent models were verified by plasma nicotine levels/PK and can be well controlled by varying the number of ECigs simultaneously activated, puff duration, inter-puff intervals and frequency of puffs with our software.
The capacity for multiple ECig allows for:
- Longer experiments than a single ECig battery or tank would last
- Higher concentrations of aerosol if multiple Eigs are delivered simultaneously
- Side-by-side testing of different ECig flavors or nicotine concentrations
For chronic intermittent ECig aerosol exposure with animals, there should be fresh air flow between aerosol deliveries (when ECigs are not activated) which removes the residual ECig aerosol and provides fresh air for normal breath of rodents. Proper air flow is important for consistency of ECig exposure and for the health of the rodents during chronic experiments in the exposure chamber, as it more closely mimics human behavior of ECig devices. The EcigAero delivers fresh air at 0 to 5 LPM for up to 40-50 air changes per hour (ACH).
The ECig aerosol, nebulizer aerosol and fresh air can all be independently programmed with 10 millisecond accuracy to regulate the dose of aerosol exposure and simulate the vaping pattern of ECig users. Programs can last up to 72 hours allowing researchers to coordinate aerosol delivery with simulated wake-sleep, day-night schedules at their convenience. In human vapers, exposure to e-cigarettes is chronic and intermittent with episodic inhalations during wakefulness and abstinence during sleep leading to circadian fluctuations of blood nicotine levels. As with conventional cigarette smoking, the episodic inhalation patterns of ECig users can induce cycles of activation, desensitization and resensitization of nicotinic acetylcholine receptors (nAChRs) in body systems that may contribute to a number of different aspects of nicotine effects, e.g. addiction and cardiovascular effects.
The EcigAero can hold a short-range antenna below the chamber for implanted telemetry systems such as the DSI PhysioTel® Implantable Telemetry that remotely measures blood pressure, ECG and other physiological parameters of the freely-moving rodent and continuously during acute or chronic exposure experiments. Our electronics and valves are isolated from the antenna and have been tested to avoid interference with the ultra-low power transmissions from implantable devices.
- The EcigAero accommodates 5 unrestrained, unanesthetized, freely-moving mice or 1 rat. It comes equipped with a water reservoir and removable tray for easy cleaning.
- Replaceable HEPA filter for use in a fume hood or lab bench.
- Small, light footprint. Device dimensions: 16 x 10 inches (footprint), height 12 inches, recommended table space 18 x 18 inches.
- Learn more about the included ValveLink 8.2 Controller
† A mouse model for chronic intermittent electronic cigarette exposure T exhibits nicotine pharmacokinetics resembling human vapers. Xuesi M.Shao, T. Friedman, et al. Journal of Neuroscience Methods, Vol 326, October 2019.