One major difference is how the oil is made—specifically, the solvent used to pull compounds from the plant material.
This guide focuses on solvent safety: why ethanol is widely used for FECO, why isopropyl alcohol appears in some traditional RSO instructions, and how to evaluate product safety using lab reports.
What are FECO and RSO?
FECO (Full Extract Cannabis Oil) is a broad term used for a concentrated cannabis extract that aims to retain a wide range of plant constituents. It is frequently produced using ethanol extraction, followed by solvent removal to create a thick oil.
RSO (Rick Simpson Oil) refers to a style of full-spectrum cannabis oil popularized online and in patient communities. Historically, some RSO instructions referenced solvents such as isopropyl alcohol (and, in older sources, other hydrocarbons). In regulated markets, producers often use methods and solvents aligned with modern safety expectations and testing requirements.
Internal resources:
Learn more about our extraction methods and
view our lab reports.
How solvent extraction works (and why “residual solvent” matters)
Solvents dissolve cannabinoids and other compounds from cannabis. After extraction, producers remove (“purge”) the solvent using controlled heat, vacuum, and time.
If the process is incomplete—or if equipment and procedures are inconsistent—small amounts of solvent can remain in the finished oil as residual solvent.
In regulated cannabis programs, residual solvent limits are typically defined by state or national rules and verified through third-party testing. Because limits vary by jurisdiction, the most practical consumer step is to review a recent COA that includes a residual solvents panel.
Ethanol in FECO: safety profile and practical considerations
Ethanol is the same type of alcohol used in beverage and food applications, and it is widely used in botanical extraction.
In the U.S., ethanol is commonly described as acceptable for certain uses in foods and pharmaceuticals when manufactured and used appropriately.
For general reference, the FDA maintains information on substances “generally recognized as safe (GRAS).”
(FDA GRAS overview).
In cannabis extraction, ethanol is often preferred because it has a more favorable toxicology profile than many industrial solvents—as long as it is properly removed and the final product is verified by testing.
- Common “safer-choice” context: ethanol is widely used in consumable product manufacturing.
- Main risk: inadequate purging or poor process controls can leave avoidable residue.
- What to look for: a COA with a residual solvents panel showing ethanol within your jurisdiction’s allowed limits.
Additional reading on cannabis science and product testing appears in peer-reviewed venues such as the
Journal of Cannabis Research.
(Journal of Cannabis Research).
Isopropyl alcohol in traditional RSO: risks and why it’s discouraged
Isopropyl alcohol (isopropanol, IPA) is a common industrial and household solvent. It is not intended for ingestion.
If residual isopropyl alcohol remains in an oil meant for oral use, it can pose avoidable health risks.
Occupational and toxicology references note that isopropanol exposure can be harmful, and ingestion can lead to poisoning.
For an overview, see the CDC/NIOSH topic page on isopropanol:
CDC/NIOSH: Isopropanol.
Why this matters for consumers
- DIY variability: home processes often can’t reliably confirm complete solvent removal.
- Testing access: most consumers don’t have analytical testing to verify residual solvent levels.
- Regulatory mismatch: unregulated products may not follow required limits or testing protocols.
If you see “RSO” sold in a regulated market, check the COA for the extraction method and residual solvents results rather than relying on legacy terminology.
Benefits of choosing ethanol-extracted, lab-tested oils (from a safety perspective)
This article is not claiming FECO is “better” for every person or condition. From a solvent-safety standpoint, consumers often prefer ethanol-extracted oils because:
- Lower ingestion concern than IPA: ethanol is generally considered more compatible with consumable manufacturing than isopropyl alcohol.
- Strong testing norms: ethanol-extracted products in regulated channels commonly include residual solvent testing.
- Process transparency: reputable brands can document inputs, procedures, and COAs batch by batch.
Who this is for (and who should be extra cautious)
This guide is for adults comparing FECO/RSO-style oils and trying to understand solvent-related safety considerations.
You should be especially cautious—and consult a licensed clinician—if you are:
- Pregnant or breastfeeding
- Managing liver disease or significant chronic illness
- Taking medications with known interactions (for example, drugs metabolized by CYP enzymes)
- New to oral cannabis products or sensitive to THC
If you’re shopping for full-spectrum oil, start with transparency:
review COAs and
browse our FECO products.
How to choose safer FECO or RSO-style products (step-by-step)
- Confirm the source is regulated and reputable.
Buy from licensed dispensaries or verified providers whenever possible. - Request a recent COA for the exact batch.
Look for a residual solvents section, plus pesticides, heavy metals, and microbials. - Check the extraction solvent listed.
Prefer products extracted with ethanol or other methods supported by robust testing and compliance. - Avoid DIY solvent extractions.
Without proper ventilation, fire safety controls, and analytical testing, DIY extraction can be unsafe. - Start low and go slow.
If using orally, begin with a very small amount and wait long enough to assess effects.
FAQs
- Is ethanol-extracted FECO safe to consume?
- It can be, if it’s produced under controlled conditions and verified by a third-party COA showing residual solvents within allowed limits. Always review the COA for the batch you’re buying.
- Is isopropyl alcohol safe in RSO?
- Isopropyl alcohol is not intended for ingestion. If residue remains in an oil meant for oral use, it may be harmful. This is a major reason many consumers avoid DIY “RSO” recipes that use IPA.
- What should I look for on a COA for solvent safety?
- Look for a Residual Solvents panel with pass/fail status (or measured values) and the lab’s name, date, batch/lot number, and testing method. Also review pesticides, heavy metals, and microbial results.
- Are there solvent-free alternatives to FECO or RSO?
- Yes. Rosin is commonly made with heat and pressure (no added solvents). It may differ in texture, composition, and use-cases compared with ethanol extracts.
- Does “full-spectrum” mean it’s safer?
- Not necessarily. “Full-spectrum” describes the range of compounds present, not the safety of the manufacturing process. Safety is more closely tied to quality controls and verified lab testing.
