Here’s something that’s been bugging me lately: the fracas over tane. “Tane” is how hash makers usually refer to Butane; but the term may also be applied to other chemical solvents like Hexane, Pentane, Propane, etc. Pretty much any solvent derived from a hydrocarbon can be called “tane.” Those solvents are some of the best used for extracting essential oils from plants. And they have been found to be safe for multiple applications. Hydrocarbon-based solvents have been used for decades in both the cosmetics and food industries. Here’s what my cursory investigation turned up (bear with me, it’s kinda technical).
Butane, Isobutane, Propane, Isopentane and the like are unpredictable substances developed from petroleum and other natural gases. Butane, Isobutane and Propane have been used to make shaving cream, cleansing products, hair conditioners, and other cosmetics. Butane, Isobutane, and Propane are compressed gases also commonly used as aerosol propellants. Isopentane can be used as either an aerosol propellant or as a solvent. These ingredients are used in cosmetics and personal care products as replacements for chlorofluorocarbons, or CFC propellants, which are known to have long-term negative environmental effects.
For cosmetics, the hydrocarbon solvent of choice is primarily Butane. This substance is known to be organically friendly and non-toxic. This solvent has also been used in the food industry for decades because its evaporative qualities leave no trace.
Butane can liquefy and remove waxes, oils, and fragile aromatics most effectively while maintaining the integrity of any particularly evaporative floral compounds. Extracted components using Butane will closely match the aroma, flavor, and taste of the original substance without being lost or destroyed during the extraction, evaporation, or recovery of the solvent. Moreover, Butane has been shown NOT to react with the food products that are being extracted. Butane is a “non-polar” solvent that has a linear molecular structure made up of hydrogen and carbon atoms that allow it to dissolve oils very effectively without reacting and creating other unwanted products. This is important to know because some people have been talking about BHO being somehow molecularly bound to the Butane used in its extraction—creating a new molecule or some other chemical. But this actually can’t happen.
As another example, Butane is commonly used as the propellant in cooking oil spray canisters because it is safe, non-toxic, evaporates completely and dissolves the oil readily so it can be sprayed out of the low pressure canister. It also provides the pressure to do so.
In a recent report entitled, Final Report of the Safety Assessment of Isobutane, Isopentane, n-Butane,and Propane, the American College of Toxicology maintained Isobutane, Isopentane, n-Butane, and Propane are non-mutagenic. The report points out that Isobutane caused very slight iridial and corneal inflammation in eye irritation studies in rabbits. And showed that n-Butane and Propane were only mildly to moderately irritating to the skin of rabbits. The report further showed that Isobutane, at 22% in a hair spray, was not toxic to rabbits in an acute inhalation study. Subchronic inhalation of Isobutane and Propane produced no toxicity in animals. In addition to these findings, the report goes on to state that “no significant systemic abnormalities occurred in human subjects during an acute inhalation study of Isobutane, n-Butane and Propane.” According to the report, Propane caused no human mucosal irritations. Furthermore, a Propane-Isobutane mixture, present at 64.5% and 70.0% in two different cosmetic formulas, caused no skin irritation in 125 human volunteers. The report concluded “on the basis of the available information that Isobutane, Isopentane, n-Butane and Propane are safe as cosmetic ingredients under present conditions of concentration and use.”
The majority of vegetable oils sold in bottles or used as other food ingredients in our grocery stores and conventional food industries are also solvent extracted oils, though most are not required to be labeled as such. Solvent extractions are largely considered more efficient than mechanical separations and have become the most common form of oil removal. However, while efficient and less expensive, these methods tend to deliver the least expensive and subsequently the lowest quality food-quality vegetable oils.
Solvent extraction of seed oils (for example olive or canola) is generally accomplished through a multi-stage process. First, the seeds are ground. The ground seeds are then purged or washed with a solvent—usually petroleum derived (the most common of which is Hexane), which releases the oil in the seed. The solvent is then “flashed off” by heating the oil in a sealed chamber. The oil and solvent blend is next heated to 212º F (100º C) to purge off the solvent. If properly done, this process leaves effectively no detectable levels of solvent in the oil. However, minute quantities (up to 25 parts per million) of solvent can remain in the meal and the finished oil. Commercial oil companies are quick to claim that the solvent is completely removed in the recovery phase of their extraction cycle. But this is difficult to verify because of the differing manufacturing practices and quality control standards employed by each processor.
So there you have it. Hydrocarbon solvents have been used to make food and skin products for a long time now. And this group of solvents has been determined to be safe for both use and consumption. So why all the trash-talk about “tane” in your erl? I think most of it is market competition; that mixed with a bit of ego.
Recently, I’ve had a few conversations with people who didn’t want to share dabs. Let me be clear here, it’s not that they didn’t want to share their dabs with me. Quite to the contrary, they refused to take dabs from me. Let me tell ya, I usually have some pretty good dabs. The dispensaries I go to carry some of the best and I am pretty particular myself. In addition, I’m friends with some of the BEST hash makers in Denver and the World, eh? Sometimes they give me things…wonderful things. And I always like to share.
When pressed as to why these people didn’t want anyone else’s dabs they routinely claimed it was due to a fear of residual solvents. I personally think a little fear is a healthy thing (pretty sure I’ve said this before), but when it drives you to repeatedly commit social faux pas perhaps it is best to more closely examine it. And that’s what I’m trying to do here. I’m trying to help a few people correct their behaviors by providing them with a little information.
It wasn’t too long ago that most dabs were created outside using open blasting techniques. In the professional community in Denver those practices have all but disappeared. But they were standard operating procedures for many years here in Colorado and before in California, where the practice originally came from (thanx Big D!). In all those years if a problem with solvent extractions was going to surface it never did. Perhaps that is due to the care of the pioneers who learned to purge their products in a vacuum oven before they learned to co-opt a vacuum-sealed closed loop conversion system.
Today most BHO extraction companies here use a closed-loop system. These provide a much safer environment in which to work while maximizing conversion rates and recycling the solvent. Afterwards, they still purge their products in a vacuum-sealed oven. This amount of care results in the almost total obliteration of any residual solvents in the final product. But this too can vary, especially since no two hash makers do it exactly the same.
But just how much solvent are we talking about here? Here it is: usually on the magnitude of 17-50 ppm on average according to the testing I’ve seen. That is not a whole-heck-of-a -lot. What does the Occupational Safety and Health Administration (OSHA) have to say about it?
From the Material Safety Data Sheet (MSDS) for Butane (source Vector Butane Gas Refill Cartridge):
• It is composed of Butane (synonyms include n-Butane, Tetrane), iso-Butane (synonyms include 2-Methylpropane, Trlmethylethane), and Propane (synonyms include LPG, Dimethylmethane, Propylhydride).
• HEALTH HAZARD DATA:
o Personal Protective Procedures: None required under normal use.
o Health Hazards: Inhalation: 1% vapor concentration may produce anesthetic effects.
o Non-toxic, but may displace oxygen causing asphyxiation.
o Eye or Skin Contact: Vapors are not irritating; liquid may cause freeze burns.
o Ingestion: Freeze burns to mucous membranes, and central nervous system depression.
In addition, OSHA notes that the vapors of Butane are not irritating. However, contact with the liquid or cold vapors may cause frostbite, freeze burns, and permanent eye damage. OSHA further notes that while ingestion is unlikely, contact of mucous membranes with liquefied butane may cause frostbite and freeze burns. Butane is considered to be non-toxic by inhalation. Inhalation of concentrations over 10,000 ppm may cause central nervous system depression such as dizziness, drowsiness, headache, and similar narcotic symptoms, but there are no known long-term effects. Acute inhalation is measured at approximately 270,000 ppm for Butane and 22,000 ppm for Isobutane. No expected chronic effects or carcinogenicity are noted.
So again I ask, why all the hub-bub? As far as I can see, practically no one’s BHO is going to be toxic even if it has a bit of butane in it. So what are we squabbling about? Look, there is nothing wrong with a bit of good clean competition. It drives innovation. But when people’s egos lead them to disparage another’s diligently processed product out of sheer spite, no one benefits; least of all the one throwing the stones.