Cannabis oil consumption has rapidly shifted toward pre-filled vaporizer cartridges, often called “carts,” becoming a highly popular method for cannabinoid delivery. This trend is driven by the convenience, portability, and discretion these devices offer compared to traditional smoking methods. This consumption method bypasses combustion by heating concentrated cannabis extract just enough to create an inhalable aerosol. Understanding the hardware, the chemical composition of the oils, and the associated health implications is necessary due to the growing interest in these products.
Defining Cannabis Vape Cartridges and Their Function
A cannabis vape cartridge is a self-contained unit designed to hold and vaporize concentrated cannabis oil. The typical cartridge is a glass or food-grade plastic cylinder, often utilizing a universal 510-thread connection at its base to screw onto a compatible battery or vape pen. This standardization makes cartridges widely interchangeable across various battery devices. The cartridge itself consists of three main parts: a sealed tank or reservoir for the cannabis oil, an integrated heating element known as the atomizer, and a mouthpiece for inhalation.
The device operates on the principle of vaporization. When the battery is activated, it sends an electrical current to the atomizer, which contains a coil, often made of nichrome or stainless steel, and a wick. This element quickly heats the surrounding oil to a temperature high enough to turn the active compounds into an aerosol—sometimes incorrectly called vapor—but low enough to prevent the material from catching fire. The resulting aerosol is then drawn through the mouthpiece into the user’s lungs, avoiding the creation of smoke and its toxic byproducts.
The Chemical Components of Cartridge Oil
The substance contained within the cartridge reservoir is a concentrated cannabis extract. The primary active compounds in this oil are the cannabinoids, such as tetrahydrocannabinol (THC) and cannabidiol (CBD), which are often present in highly refined forms like distillate, sometimes reaching purities of 90% or more. These cannabinoid concentrations determine the psychoactive and therapeutic effects of the product.
Beyond the major cannabinoids, the oil also contains a variety of terpenes, which are volatile aromatic compounds found naturally in the cannabis plant. Terpenes are responsible for the distinct flavor and aroma profiles of different strains, and they are also thought to modulate the overall effects of the cannabinoids, a concept sometimes referred to as the “entourage effect”. Common examples include limonene for a citrus scent and myrcene for an earthy, musky aroma.
Manufacturers sometimes add diluents or cutting agents to the highly viscous cannabis oil. These agents are used primarily to thin the extract for better wicking in the cartridge and to increase product volume. Historically, these substances have included propylene glycol (PG), vegetable glycerin (VG), polyethylene glycol (PEG) 400, and medium-chain triglycerides (MCT) oil. The illicit market also utilized Vitamin E Acetate as a thickening agent to simulate high-quality oil, though its inhalation when heated proved highly damaging.
Vaping and Potential Health Considerations
The aerosol produced by vaporization carries its own set of health considerations. The inhaled cloud is an aerosol, a suspension of fine liquid and solid particles that can carry chemical residues deep into the lungs. When certain thinning agents are heated, they can break down into toxic carbonyl compounds, such as formaldehyde and acetaldehyde, which are known carcinogens.
A major public health concern arose from the 2019 outbreak of E-cigarette or Vaping Product Use-Associated Lung Injury (EVALI), which resulted in thousands of hospitalizations and dozens of deaths across the United States. The vast majority of these cases were strongly linked to the use of black-market THC cartridges containing the additive Vitamin E Acetate. When heated and inhaled, this oil-based compound can coat the lung’s surfaces, leading to severe respiratory distress.
Another risk involves the hardware itself, where the atomizer’s metal heating coil can leach trace amounts of heavy metals into the aerosol, including nickel, chromium, tin, and lead. The level of these contaminants can depend on the device’s quality and the temperature at which it is operated.
The source of the cartridge is a determining factor in safety, as legal, regulated markets require third-party lab testing to screen for harmful additives, pesticides, and heavy metals. This safeguard is completely absent in the unregulated market. Due to the relative newness of this consumption method, the full long-term effects of chronic cannabis aerosol inhalation remain largely unknown.