What comes out of a chemical conversion
These compounds start in a plant and finish in a reactor. A cannabinoid extracted from hemp is chemically converted into a different molecule, which is why the category is called semi-synthetic rather than natural or synthetic.
Every chemical conversion produces the intended product alongside by-products, unreacted starting material, and traces of whatever made the reaction happen. Routine analytical panels are built to look for the first of those.
This page covers what the conversion is, what it produces besides the target, what the analytical gap actually is, how the regulatory position has moved, and what a buyer cannot verify.
⚠️ Scope. This page describes a process and what can be verified from documents. It does not describe what a product does to a person, gives no amounts, and does not replace a healthcare professional.
🔴 What semi-synthetic means
The starting point
A cannabinoid extracted from hemp, most often the abundant one, which is inexpensive and available at scale.
The conversion
A chemical reaction transforming that molecule into a different one, using reagents and generally a catalyst.
Why it is done
Because the starting material is cheap and the products are not otherwise available in useful quantities from the plant.
What the term encodes
Plant origin, chemical transformation. Neither half on its own describes the category accurately.
What a conversion produces
The target compound
The intended product, at whatever yield the process achieved.
Isomers and epimers
Structurally related forms produced alongside the target, sometimes in substantial proportion, with their own distinct properties.
Unreacted starting material
Whatever did not convert, which remains in the mixture unless it is separated out.
By-products and residues
Compounds formed by side reactions, plus traces of reagents and catalyst. Both are process-specific.
🔴 The analytical gap
What routine panels look for
A defined list of cannabinoids, quantified against reference standards. The list is what the method was built around.
What they do not look for
Compounds not on that list, including by-products specific to a conversion process. A method does not find what it was not asked to find.
Why that matters here
Because the by-products are exactly what distinguishes a well-run conversion from a poorly run one, and no routine certificate addresses them.
What would address it
A method developed for the specific process, looking for its specific by-products and residues. It exists in principle and is rarely commissioned.
The catalyst question
What a catalyst does
Makes a reaction proceed that would otherwise be slow or not occur. It is not consumed and it is present in the reactor.
What is used
Metal catalysts are common in reactions of this type. Which metal depends on the process.
Why that matters
Because catalyst traces can remain in a product, and heavy metal panels are built around environmental contamination rather than process residues.
What a panel would need to cover
The specific metals used in that conversion, at limits appropriate to the route. A standard panel may not include them.
The isomer question
What happens
Many conversions produce a mixture of structurally related forms rather than a single one.
What that means
The proportions vary between processes and between batches, and the mixture is what is sold.
Whether it is reported
Where a certificate reports a total for the compound, it may not distinguish between the forms present.
Why it matters
Because the forms are different molecules with different properties, and a total conceals the composition.
The regulatory position
Where it started
Products of this kind appeared in the European market from around 2022, initially outside any specific control.
What the monitoring found
The European Union Drugs Agency has reported on such compounds through its early warning function, which is what the system exists to do.
What member states did
Many introduced national controls, at different times and with different scope. The position now differs substantially between countries.
What that means practically
Legality is country-specific and it has changed repeatedly. Anything written about it dates quickly, including this page.
The novel food dimension
The separate framework
Foods without significant consumption history in the Union before the reference date require authorisation before being placed on the market.
How it applies here
A compound produced by chemical conversion, without a consumption history, sits squarely within that description.
What that requires
An authorisation, which involves a safety assessment. That process exists and has not been completed for these compounds.
The consequence
Sale for ingestion without authorisation is not compliant with the food framework, independently of any national control.
What is not known
The safety profile
These are recent compounds with limited study. Absence of evidence of harm is not evidence of absence.
The by-product profile
Which compounds a given process produces, in what quantities, and what is known about them. Rarely published.
The long-term picture
Non-existent by construction. The compounds have not been in use long enough for one to exist.
Why this belongs on the page
Because it is the honest state of the evidence, and it is what a buyer is actually deciding under.
What a certificate for one of these would need
The target compound
Quantified, with the isomeric composition stated rather than a single total.
The starting material
How much remained unconverted, which is a straightforward measurement and a real indicator of process control.
Process-specific residues
Catalyst metals and known by-products, at limits appropriate to the route. This is the part that requires a purpose-built method.
The standard panels
Everything that applies to any concentrate: pesticides and microbiology from the input material, residual solvents from the processing.
Why this category is difficult to write about
The pace
Compounds appear and are controlled faster than anything written about them stays accurate.
The vocabulary
New abbreviations arrive constantly, many differing by one character, describing genuinely different molecules.
The claims
Frequently made confidently about compounds with very little published work behind them.
Our position
Describing the chemistry and the regulatory structure, which change slowly, rather than the status of any particular compound, which does not.
What we sell and what we do not
Our position
We do not regard this category as equivalent to plant-derived products, and where such products are offered anywhere it is under national rules that vary.
Why we say so here
Because a page describing an analytical gap should be clear about the writer’s own position.
What we would want before selling anything of the kind
A purpose-built analysis covering by-products and catalyst residues, and a settled regulatory position in the market concerned.
What that amounts to
Not a judgement about the compounds. A statement about what documentation would make them assessable, which does not currently exist.
Why the analytical gap exists
Methods are built for known targets
A chromatographic method quantifies compounds against reference standards. Without a standard for a compound, the method cannot report it even if it is present.
Reference standards are the constraint
They must be synthesised, characterised and made commercially available. For a newly appearing by-product, that lag is years rather than months.
What laboratories do meanwhile
Report what they can measure. A certificate showing only the target compound is an accurate report of what the method covered.
Why that is not the laboratory’s failure
They answered the question asked with the method available. The gap is in what was commissioned rather than in how it was performed.
What a purpose-built method would involve
Identifying the by-products
Requires knowing the process, which is proprietary, and analysing the product by methods that detect unknowns rather than quantifying knowns.
Obtaining or synthesising standards
For each compound to be quantified. It is the expensive and slow part.
Validating the method
Demonstrating that it measures what it claims, at the levels required. Standard analytical practice and a real cost.
Why nobody does it
No requirement, no commercial demand, and a result that would differentiate producers in a way most of them would rather avoid.
Reading a certificate for one of these
What you will generally see
The target compound quantified, sometimes a broader cannabinoid panel, and the standard contaminant panels.
What that establishes
That the target is present at a stated level, and that the input material carried acceptable levels of the usual contaminants.
What it leaves open
Everything specific to the conversion: isomer ratios, unreacted material, by-products and catalyst residues.
The honest reading
A partial answer, accurately reported, to a narrower question than the product raises.
The comparison with plant extraction
What extraction does
Separates compounds that were already present. Nothing new is created and the panels were designed for exactly that situation.
What conversion does
Creates molecules that were not there before, alongside others nobody specified. It is a different kind of process.
Why the same panels do not transfer
Because they were built around a process that adds nothing. Applying them to one that does leaves the additions unexamined.
What that means structurally
The documentation framework in this category has not caught up with a production route that arrived recently.
Where the market is heading
The regulatory direction
Toward control, in most member states, at different speeds and with different scope.
The analytical direction
Slowly toward better methods, as standards become available and as authorities develop reference procedures.
The commercial direction
Difficult to predict, and it has historically involved new compounds appearing as previous ones are controlled.
What that pattern produces
A category where the documentation always lags the product, structurally rather than through anyone’s negligence.
The three questions, if you are considering one
What is the isomeric composition
Not a total for the compound, but the proportions of the forms present. They are different molecules and a total conceals which you have.
What was the catalyst, and was it tested for
A specific metal, and whether the heavy metal panel covered it. A standard panel is built around soil contamination rather than reactor residues.
How much starting material remains
A straightforward measurement, and the clearest single indicator of how well the conversion was controlled.
Why these three
Because they are the questions a conversion raises and an extraction does not, and because none of them appears on a routine certificate.
What this page is not saying
Not that these compounds are dangerous
We have no basis for that claim and it would be a statement about effects. What we say is that the documentation does not currently answer the questions the process raises.
Not that plant extraction is above scrutiny
It has its own residual solvent question, its own contaminant routes, and its own panels for exactly that reason.
Not that the analytical gap is permanent
Reference standards become available, methods get developed, and authorities publish procedures. It is a lag rather than an impossibility.
What it is saying
That in this one category the usual advice runs out. Reading the certificate remains correct and it stops short of the question that distinguishes these products.
A short glossary
Semi-synthetic
Derived from a plant compound and chemically transformed into a different molecule, which is neither natural nor fully synthetic.
Catalyst
A substance making a reaction proceed without being consumed, whose traces can remain in the product.
Isomer
A molecule with the same formula and a different arrangement, produced alongside a target compound and with distinct properties.
Early warning function
The Union mechanism through which new psychoactive substances appearing on the market are reported and assessed.
Novel food
A food without significant consumption history in the Union before the reference date, requiring authorisation before being placed on the market.
The five checks that apply to any product
The batch certificate
Request it with the number printed on the packaging. A general document for the product line does not cover this batch, and those differences are exactly what it should record.
Total THC
Delta-9-THC plus THCA multiplied by 0.877, because THCA becomes THC under heat and the limit applies to the sum, not to either value alone.
Price per milligram
A division, not an opinion. The only figure that makes two products comparable, whatever the format, process and pack size.
The claims
Without an authorisation number in the EU Register these are assertions, not data — and for cannabidiol that register contains no authorised entry to this day.
The seller’s details
Company name, address and contact. Without them there is also no counterparty to turn to if something turns out to be wrong.
How this connects to the rest
With isolates
A purified compound gives no indication of its origin. The question of how it was produced is the same question.
With residual solvents
Conversion processes use solvents and reagents. The panel is relevant and it is built for extraction rather than for synthesis.
With the novel food framework
It applies to these compounds directly, and no authorisation has been completed.
With the certificate
The gap described here is the clearest case in this subject of a document that measures the wrong things.
What this is for in practice
On legality
Country-specific and changing. Check the current national position rather than any page, including this one.
On certificates
A standard panel does not cover what matters here. Ask specifically about by-products and catalyst residues.
On claims
The published work is limited. Confidence in a description is not evidence about a compound.
On the category generally
It is genuinely different from plant-derived products, and the documentation available does not yet reflect that difference.
Frequently asked questions
What does semi-synthetic mean? Derived from a plant compound and chemically converted into a different molecule. Neither natural nor fully synthetic.
Why are they made this way? Because the starting material is cheap and abundant, and the products are not available in useful quantities from the plant.
What does a conversion produce besides the target? Isomers, unreacted starting material, side-reaction by-products, and traces of reagents and catalyst.
Do routine panels find those? No. A method quantifies the compounds it was built around. It does not find what it was not asked to look for.
What about catalyst residues? Heavy metal panels are designed around environmental contamination. They may not cover the specific metals a given process uses.
Are they legal? It depends on the country and it has changed repeatedly. Many member states introduced national controls from 2022 onward.
What about food law? The novel food framework applies and no authorisation has been completed. Sale for ingestion without one is not compliant.
Is there safety data? Limited. These are recent compounds and there is no long-term picture by construction.
What would a proper certificate cover? Isomeric composition, unreacted starting material, process-specific by-products and catalyst residues, plus the standard panels.
Why is this page cautious? Because the documentation that would make the category assessable does not currently exist, which is a factual statement rather than a judgement.
What we check and what we do not
We check what can be checked from documents: official registers, declared contents, certificates of analysis, arithmetic. We test no products, rank nothing, and assert no effects.
Everywhere else in this subject the argument is that a certificate answers the questions a label cannot. Here it does not, and that is the point of the page: the analytical panels in routine use were built for plant extracts, and they measure a conversion product as though it were one.
What is missing is not exotic. Isomeric composition, unreacted starting material, catalyst residues and process by-products are all measurable by established methods. Until somebody commissions them, this is the one category where the usual advice — read the certificate — does not reach the question that matters.