The staff at High Times carefully avoided providing step-by-step instructions on how to make Butane Hash Oil, BHO, wax, glass, shatter, or whatever butane-extracted marijuana concentrates are called in a particular region. Instead, they offered excellent tips on refining the finished product by properly purging marijuana concentrates of the solvent used to dissolve the cannabinoids from the plant material.
NSN News must once again remind its readers that home BHO operations are highly dangerous and carry a serious risk of fire, explosion, and criminal prosecution. Only those with an appropriate space and the right equipment should attempt this process.
One of the biggest quality concerns with BHO is the cleaning or purging of any remaining solvent, butane, which is not great to be vaporizing and inhaling. Some states with medical marijuana programs now offer laboratory testing of concentrates to ensure parts per million of butane is below an acceptable threshold.
If CO2 or nitrogen was used in the extraction, the raw extract should be placed in ethanol alcohol (for example, the grape-spirit ethanol available from organicalcohol.com) and then warmed slightly to
approximately 120°F, until you see the extract dissolve into the grape spirits. When using butane, mix one part grape spirits with two parts butane, and the cannabinoids will migrate to the alcohol while the butane is evaporating. For this procedure, start with instrument-grade N-butane as the primary extraction fluid, and then introduce the alcohol.
They go on to outline the process of re-bottling the product (once all the CO2, nitrogen, or butane is absolutely gone) and freezing said bottles for a pure product. The end result is a BHO that should be purged of plant waxes. It is then filtered, strained, and dried. The process is called winterization, and it can be done with anything, including the nasty resin scraped from the inside of pipes.
All in all, the High Times article is not for newbies, but those already established in the concentrate market. In fact, the article argues for higher standards of concentrate production, and advises the use of expensive vacuum pump devices and laboratory testing to ensure the quality of the product.
Concentrates need to be tested for residual solvents and then safe levels established for these as well. Most labs simply do broad-spectrum pesticide/fungicide tests, but better tests are necessary for commonly used insecticides and fungicides such as neem oil, sulfur, and the organic substances commonly used in various insecticides and repellants. Just because a substance is labeled organic doesn’t mean it’s safe at concentrated levels. For consumers, the safest concentrates are produced by vertically integrated
manufacturers — those that grow their own marijuana and can reliably state that no pesticides or foliar sprays were used.
In the concentrate market, much moreso than the flower market, it is important to know and trust the provider selling the product and the person making it. Poorly purged BHO can have a negative health impact on users. Asking questions is one of the best ways to ensure if a BHO manufacturer is following a safe, clean process, but independent laboratory testing for residual solvent is also very important.