THC is tetrahydrocannabinol, one of the chemical compounds (cannabinoids) found in the cannabis plant. It is primarily responsible for the 'high' experienced by marijuana users. THC is present in both marijuana and hemp, but hemp must not contain more than 0.3% of THC on a dry-weight basis. Marijuana contains higher concentrations of THC (sometimes more than 50%). THC interacts with the body’s endocannabinoid system to produce intoxicating effects. The endocannabinoid system assists with stress recovery, activates the immune system response, and protects the nervous system. Common isomers of THC include Exo-THC, Delta-7 THC, Delta-8 THC, Delta-9 THC, and Delta-10 THC.
THC is legal in Illinois. The Illinois Cannabis Regulation and Tax Act (CRTA) legalized marijuana and its derivatives for adults aged 21 years and older. In addition, Illinois enacted the Illinois Industrial Hemp Act (SB 2298) to allow the cultivation, production, sale, and use of industrial hemp and its derivatives in the state. Hence, both hemp-derived THC and marijuana-derived THC are legal in Illinois. Illinois residents may possess up to 500 milligrams of marijuana-derived THC products, while non-residents may possess up to 250 milligrams. All forms of THC products are allowed in the state.
The THC content in the Cannabis sativa plant varies. Hemp contains 0% to 0.3% THC while some marijuana strains contain over 25% THC. The concentration of THC in marijuana has gradually increased over the years. A study carried out in the 1960s by the National Center for Biotechnology Information revealed that cannabis strains had less than 2% THC. THC content increased to about 4% in the early 1990s. Another study was done by the National Center for Natural Products Research (NCNPR) in conjunction with the National Institute on Drug Abuse (NIDA) on marijuana potency. It was discovered that THC potency in cannabis between 1995 and 2021 increased from 3.96% to 15.34%. The test was conducted on cannabis samples seized by the Drug Enforcement Administration (DEA). THC concentration varies per strain, and marijuana strains with over 20% THC are common in Illinois. Some popular cannabis strains and their THC potency in the state include:
The Godfather: 35% THC
Primus OG: 20 to 28% THC
Bubba Fett: 27% THC
Dale OG: 20 to 27% THC
Light of Jah: 23 to 26% THC
Girl Scout Cookie: 17 to 28% THC
Pineapple Express: 17 to 24% THC
Silver haze: 23% THC
Thai: 22% THC
The potency of marijuana is determined by its THC concentration; the higher the THC concentration, the more potent it is. The THC potency of weed also depends on the part or derivative of the cannabis plant. The flowering part of the cannabis plant typically has the highest THC content. In addition, cannabis concentrates and THC distillates have very high THC contents, sometimes as high as 90%. Marijuana product manufacturers are mandated by law to indicate the THC concentration level on the labels of cannabis products in Illinois. The labels must also indicate the concentration levels of cannabidiol acid (CBDA), cannabinoid (CBD), and tetrahydrocannabinolic acid (THCA). THCA is converted to THC during decarboxylation, and their concentration levels are often different. Other THC compounds found in cannabis in decreasing order of abundance are as follows:
Delta-9 Tetrahydrocannabinol (Delta-9 THC)
Delta-7 Tetrahydrocannabinol (Delta-7 THC)
Delta-8 Tetrahydrocannabinol (Delta-8 THC)
Delta-10 Tetrahydrocannabinol (Delta-10 THC)
THC is legal in Illinois under the state’s Cannabis Regulation and Tax Act. Residents aged 21 years and older may possess up to 30 grams of marijuana, 5 grams of marijuana concentrate, and up to 500 milligrams of THC-infused products. Non-residents in the state may possess half of the residents’ legal limits. Medical marijuana patients in Illinois may possess up to 2.5 ounces (70.87 grams) of cannabis in 14 days.
The 2018 Agriculture Improvement Act (2018 Farm Bill) and the Illinois Industrial Hemp Act allow residents to possess unlimited amounts of hemp-derived THC products, provided their THC content does not exceed 0.3%. Dispensaries and hemp stores may sell all forms of hemp-derived THC products. Online stores in Illinois are also allowed to sell and deliver hemp-derived THC products to consumers.
Illinois considers hemp-derived THC products as low-THC products and marijuana-derived THC products as high-THC products. It is illegal to drive a vehicle while intoxicated with THC in Illinois. In addition, driving or being in control of a vehicle with 5 nanograms or more of THC concentration in the blood or an excess of 10 nanograms in the saliva or urine is illegal. However, registered medical marijuana patients are exempted from these THC limits and may not be prosecuted as long as they do not appear impaired while driving.
THC can be detected by drug tests such as blood, urine, saliva, and hair follicles tests. However, the possibility of detection and detection window depends on a number of factors, including the following:
Type of test: The hair follicle test is the most sensitive test for THC metabolites as it can detect its usage three months after the last use. Blood and urine tests have shorter detection windows
The quantity consumed: The more THC is consumed, the higher the likelihood of detection
Frequency of use: The more often THC is consumed, the longer it remains in the body
Body metabolism rate: Metabolism also determines how long THC metabolites can be detected in the body. The faster the metabolism rate, the harder it is to detect THC in a test
Age: THC can be detected for a longer time in older persons than in younger consumers
Means of consumption: THC consumed by smoking is eliminated from the body faster than other means of consumption
While the ‘high’ effects of THC can last for 5 to 6 hours, its metabolites can remain in the body for up to 3 months. When THC is consumed, the liver breaks it down into metabolites and sends it to some parts of the body, including the brain, where it induces psychoactive effects. Most of the metabolites are eliminated from the body within 48 hours, but some are stored in the body’s fatty tissues.
THC metabolites can be detected in blood and urine samples for up to 48 hours after the last use. They can be detected in saliva samples for up to 4 weeks after the last use and in hair follicles for up to 3 months after it was last consumed.
THC oil is a concentrated marijuana oil extracted from the marijuana plant. It is made when hashish or marijuana is macerated, infused, or percolated, leaving a viscous liquid remnant after evaporation. THC oil is safe to consume and is sold in pens and vape carts. It produces psychotropic ‘high’ effects when consumed. THC oil and CBD oil are different due to their sources. While CBD oil is derived from industrial hemp, THC oil is derived from marijuana.
THC distillate is a purified form of THC derived from marijuana containing only THC molecules. THC distillate is devoid of other compounds, unlike THC oil. It is manufactured by vaporizing THC oil to form a distillate of thick oil. While THC distillate is derived from cannabis plants, CBD distillate is derived from hemp plants. THC distillates induce psychoactive effects in consumers faster than any other form of THC. It is safe to consume but must be ingested moderately due to its high THC potency. It can be vaped, consumed orally, or applied topically.
Illinois residents can get marijuana-derived Delta-9 and Delta-8 THC products from licensed cannabis dispensaries in Illinois. Recreational weed consumers can order THC products online but must physically pick them up from the dispensaries. Only medical marijuana patients can have THC products delivered to their residences. Marijuana-derived THC products available in Illinois include THC gummies, edibles, tinctures, creams, and capsules. All forms of hemp-derived THC products can be purchased from hemp shops, gas stations, and dispensaries in Illinois. They may also be purchased from online stores.