By Rick Scarpello, CEO of Medically Correct
Let’s discuss cannabis extraction methods with facts and not religion. I’m pro-faith, but let’s call it what it is. When someone has faith in their opinion and not scientific evidence, it’s a religious endeavor. I will try to stay with what we know and let religious zealots scream from the rooftop about co2 being better.
- Hydrocarbon extractions are the most widely used method in the world for consumables.
- CO2 extracts are hardly used for consumption products, estimated at 2 percent (2%).
- Hydrocarbons have been used in the food chain for 50 plus years.
- Hydrocarbon extractions are being done every day, in almost every state for food and ingredients.
- Everyone is consuming hydrocarbons everyday while they eat from things flavor extracted oils like sunflower and canola.
- You breathe in butane through the air, even if you don’t like it. According to the National Institute of Health (NIH), “The average daily intake of n-butane via air is 183mg.”
Extraction methods use a solvent to run through the plant material and squeeze out the much desired oil, or errl as industry folks call it. The solvents range from; water, co2, ethanol (alcohol), and hydrocarbons. Solvents aren’t inherently bad, thanks to science, remember?
Yes, I gave away the ending with the title of this article, but it is still a fun read for pro- and anti-butane people. It will make some of you applaud, and others curse. You will win either way because we are talking about cannabis being more legitimate than the previous 100 years—and we are all pro-cannabis.
Comparing Extractions Methods
Let’s talk about each extraction method and try to conclude which is best. Since it is imperative to the conversation, I will define ‘best’ for this exercise.
To be the best you have to do few a things for me. As a for-profit business operator, you want to ensure your extract is as pure as possible without much post-process, as that costs more money. When making medicine for children and the elderly, as is the case for my business, I need more good quality constituents and clean results. I want less waxes and fatty acids, and more flavonoids, terpenoids, cannabinoids, and trichome heads.
Cannabis Extraction with Water
The basic principle is that plant material (either dry or fresh-frozen generally) is mixed with cold water and ice, then agitated manually or mechanically in order to break off the now-brittle trichome heads. Then, the solution is filtered through specifically-sized screens.
Using water at home is by far one of the easiest methods; however, this method results in a less pure medicine and leaves more plant matter behind. It can also mold if dried improperly. It is an issue when molds and microbes remain on the plant matter after the process.
Toxicity Summary: Accidentally consuming too much water under normal circumstances is exceptionally rare. Nearly all deaths related to water intoxication in normal individuals have resulted either from water-drinking contests, in which individuals attempt to consume large amounts of water, or from long bouts of exercise during which excessive amounts of fluid were consumed.
Cannabis Extraction with Ethanol (alcohol)
Ethanol is heavily used in the food industry for extractions. Most flavors or edible extractions use alcohol. A lot of machine companies lean this way, and you can find dozens in a quick Google search or on Linkedin. Alcohol is very clean, easy to remove, and easy to retain after the extraction. This is a simple way to extract and should be a commonly used extraction method for home use. This method has the potential to over extract polar and non-polar undesirables. It is very flammable and combustible but less volatile than Butane.
Toxicity Summary: Ethanol is a 2-carbon–chain alcohol; the chemical formula is CH2 CH3 OH. It is ubiquitous throughout the world and is a leading cause of morbidity across cultures. Ethanol is the most common psychoactive drug used by children and adolescents in the United States and is one of the most commonly abused drugs in the world, according to Medscape.
Cannabis Extraction with CO2
CO2, also known as carbon dioxide, is odorless and colorless. Since leaks are undetected and can lead to asphyxiation fatalities, it has been recognized as a workplace hazard for a century. Highly compressed bottles are rarely used in extractions as a whole. CO2 is less pure of an extraction since it can be over-extracted and create more lipids and wax. The H2O content in the extract after processing is a concern as well. For the first time in history, patients are potentially smoking water into their lungs that could result in pneumonia.
The food industry hardly makes big machinery for this purpose. The Cannabis industry has embraced this method and it’s winning big time. The number 1 method to extract cannabis (according to the Cannabist) is CO2. This process has a lot of money behind it and all of the big players touting its ways. Many new companies are making small scale machinery for Cannabis.
Toxicity Summary: Carbon dioxide (CO2) is a toxic gas at high concentration, as well as an asphyxiant gas (due to reduction in oxygen). Irritation of the eyes, nose, and throat only occur at high concentrations. Gas masks may have limited use in high CO2 concentrations due to the lack of oxygen. Thus, it has been recommended that working or living areas should be immediately evacuated when concentrations exceed 1.5% by volume (the occupational short-term exposure limit value). Ambient guidelines for CO2 do not exist.
Cannabis Extraction with n-butane (hydrocarbons)
The #1 extraction method in the world is hydrocarbon extraction for food and ingredients. Many companies are making large equipment—some are the size of a truck and some are two stories tall—but in a variety of versions. Since the 1970s, several different hydrocarbons have been used. From propane to hexane, we consume them in restaurants and at home everyday. It is volatile and flammable. There are some concerns about residual solvent if not properly purged.
Many small new companies are making machinery for butane or propane extractions in cannabis. It can be done 100% safely with proper personnel and proper SOPs (Standard Operating Procedures). There are now engineer’s and industrial hygienists involved in peer reviews for this equipment. You can find Class 1, Division 1 extraction environments so there is nothing safer to use.
Toxicity Summary: n-Butane is a colorless, flammable gas at room temperature. It occurs as a component in natural gas from which it is refined. n-Butane is used as fuel, refrigerant and aerosol propellant. The acute toxicity of n-butane has been studied after inhalation exposure in experimental animals. LC50 (4h) was 658 mg/l in rats and LC50 (2h) was 680 mg/l in mice. In dogs, lethal concentrations ranged from 474 to 592 mg/l. A concentration of 308 mg/l caused light anesthesia in mice within 25 minutes, and an exposure to 521 mg/l had similar effect within one minute.
There is no evidence that butane is more dangerous to use than co2, water, or ethanol. In fact, the evidence may actually be the contrary. CO2 companies are at the forefront of the complaint, and I know their motives since we saw it in paper mills versus hemp 100 years ago.
We have safely used hydrocarbon extractions since the 70s in most canola and corn oils. Butane is in the air we breathe. So many products in our daily life include butane or hydrocarbons; consider that TBHQ (tert-Butylhydroquinone) is in mayonnaise, peanut butter, corn oil, canola…it’s everywhere.
For my money, hydrocarbon extractions are better. It’s the political battle that is the real concern.
Footnote: “Almost all corn oil is expeller pressed, then solvent extracted using hexane or 2-methylpentane (isohexane). The solvent is evaporated from the corn oil, recovered, and re-used. After extraction, the corn oil is then refined by degumming and/or alkali treatment, both of which remove phosphatides. Alkali treatment also neutralizes free fatty acids and removes color (bleaching). Final steps in refining include winterization (the removal of waxes), and deodorization by steam distillation of the oil at 232–260 °C (450–500 °F) under a high vacuum.”