Lab Testing Policy

1. Scope of this policy

This policy explains how the goods sold through this store are tested, what they are tested for, and how you can check the result for the exact batch you received. It applies to every cannabinoid and hemp-derived product listed on the site: flower, pre-rolls, extracts and concentrates, vape hardware filled with cannabinoid material, edibles, tinctures and topicals.

The policy describes a testing programme. It is not a specification for any individual product, and it says nothing about the legal status of any product in any country. Analytical limits differ between markets. Where a destination market applies a stricter limit than the one described here, the stricter limit governs release of that batch to that market.

Nothing in this policy is a medical or therapeutic claim. Test results describe composition and purity. They describe nothing else.

2. Laboratories and accreditation

All release testing is performed by third-party laboratories accredited to ISO/IEC 17025 for the specific methods used. Accreditation to the standard in the abstract is not enough. Each method we rely on — potency, pesticides, metals, solvents, microbiology, mycotoxins — must appear on the laboratory's published scope of accreditation, issued by an accreditation body that is a signatory to the ILAC Mutual Recognition Arrangement.

We do not operate our own release laboratory. In-house instruments are used for process monitoring only, and their output never appears on a certificate of analysis or supports a release decision.

We hold the current accreditation certificate and scope for every laboratory on our panel, re-verify them at least annually, and re-verify them again whenever a laboratory notifies a change of scope. [TESTING LABORATORIES] are named on each certificate of analysis together with their accreditation number.

• ISO/IEC 17025 accreditation, with the relevant method on the accredited scope
• Validated methods with documented limits of detection and quantification
• Participation in proficiency testing or inter-laboratory comparison for each analyte class
• Measurement uncertainty calculated and available on request
• A quality manual, a deviation and out-of-specification procedure, and a named authorised signatory

3. Laboratory independence and conflicts of interest

The laboratories on our panel are independent of us and of our suppliers. There is no common ownership, no cross-directorship, no consultancy arrangement and no revenue share between a laboratory and any party with an interest in the outcome.

Laboratory fees are fixed per method. They are never tied to the result of a test, to pass rates, or to the volume of product released. Nobody on the commercial side of the business may contact a laboratory about a pending result, and cultivation and production staff have no access to the submission portal.

We do not shop for a favourable number. Once a batch has been submitted, it may not be withdrawn and re-submitted elsewhere: the first valid report is the report of record. Blind duplicate samples go to a second accredited laboratory on a rolling basis, and material disagreement between two laboratories opens an investigation rather than a choice between reports.

4. Sampling methodology

A result is only as good as the sample behind it. Sampling is carried out by the laboratory, or by a trained sampler working to the laboratory's written procedure, and never by the person who produced the batch.

Samples are drawn as multiple increments from different positions across the batch — commonly the square root of the number of units, rounded up — then combined and homogenised into a single composite laboratory sample. Flower is ground and mixed before subsampling. Extracts are warmed and stirred to uniformity. Edibles are sampled as whole finished units, so that dose per unit is measured in the form it is sold in.

Every sample travels under chain of custody: unique sample identifier, batch code, matrix, mass, sampler, date and time, seal condition and transport temperature. A broken seal or an unexplained gap in custody voids the sample, and sampling starts again.

5. The standard test panel

Every batch is screened against the panel below before it is released for sale. Product type determines which parts apply: residual solvents apply to solvent-processed goods, water activity to flower and other dried plant material, dose uniformity to edibles.

• Cannabinoid potency — acidic and neutral forms, by HPLC with UV or diode-array detection
• Terpene profile — by headspace GC-MS or GC-FID
• Residual pesticides and plant growth regulators — by LC-MS/MS and GC-MS/MS
• Heavy metals — lead, cadmium, mercury and arsenic, by ICP-MS after acid digestion
• Residual solvents — by headspace GC-MS, for extracts and any solvent-processed material
• Microbial contaminants — total aerobic count, yeast and mould, bile-tolerant Gram-negative bacteria, Escherichia coli and Salmonella
• Mycotoxins — aflatoxins B1, B2, G1 and G2, and ochratoxin A
• Water activity and moisture content — for flower, pre-rolls and other dried material
• Foreign matter and visual inspection — stems, seeds, insects, visible mould, packaging debris

6. Cannabinoid potency, terpenes and label tolerance

Potency is measured by liquid chromatography without decarboxylation, so acidic and neutral cannabinoids are reported separately. Totals are then calculated with the molar conversion factor of 0.877 — total THC equals THCA multiplied by 0.877, plus delta-9-THC — because the acid form loses a carboxyl group when it is heated. Results are reported as per cent by weight for solids and as milligrams per unit or per millilitre for edibles and liquids. Anything below the limit of quantification is reported as such, never as zero.

Label claims are matched to the batch result within the tolerance stated on the product page and within the tolerance the destination market allows. Plant material is not a manufactured chemical: potency varies between harvests, and between the top and the bottom of a single plant. A batch outside the label tolerance is relabelled to its measured value or held. It is never sold under a claim it does not meet.

Terpenes are volatile and are lost to heat, light and time, so we profile them per batch. The panel covers the terpenes commonly present at measurable concentrations, including myrcene, limonene, beta-caryophyllene, linalool, alpha-pinene, beta-pinene, terpinolene, humulene and ocimene, reported in per cent by weight or milligrams per gram. Terpene content is descriptive information about composition. It is not a safety parameter, it carries no pass or fail limit, and no effect is claimed from it.

7. Pesticides and heavy metals

Pesticide screening covers the residues relevant to cannabis cultivation, including the plant growth regulators and systemic fungicides that survive drying and are concentrated by extraction. Analysis is by tandem mass spectrometry, which detects residues far below the level at which they could be seen, smelt or tasted.

Heavy metals are measured by ICP-MS after microwave-assisted acid digestion. Cannabis is a known hyperaccumulator: it draws metals out of soil and irrigation water and holds them in plant tissue. Lead, cadmium, mercury and arsenic are therefore tested on every batch, whatever the grower says about the medium. Vape hardware is tested with its contents, because metals can also migrate from a coil or a cartridge.

Limits are the strictest of the destination market's statutory limit, the limit in the applicable pharmacopoeial monograph or in Regulation (EU) 2023/915 and Regulation (EC) No 396/2005 where those apply, and our own internal specification. Inhaled products are held to tighter metal limits than ingested products, because vaporisation and combustion deliver metals to the lung far more efficiently than digestion delivers them to the bloodstream.

8. Residual solvents in extracts

Any product made with a solvent — butane, propane, ethanol, a hydrocarbon blend, or carbon dioxide with a co-solvent — is tested for what remains after purging. Rosin, dry sift and other solventless goods are tested only where a solvent was used elsewhere in their process chain.

Analysis is by headspace gas chromatography with mass-spectrometric detection. Limits follow the ICH Q3C solvent classes as applied in Ph. Eur. chapter 5.4 and USP chapter 467. Class 1 solvents such as benzene are unacceptable at any practical level and carry limits in the low parts per million. Class 2 solvents such as hexane, methanol and toluene carry defined permitted daily exposures. Class 3 solvents such as ethanol, acetone and ethyl acetate are controlled by a general threshold.

A batch above any solvent limit cannot be fixed by repackaging. It goes back for further purging and is retested from a fresh sample, or it is destroyed.

9. Microbial contaminants, mycotoxins and water activity

Dried plant material is an agricultural product and carries an environmental microbial load. Testing covers total aerobic microbial count, total combined yeast and mould count, bile-tolerant Gram-negative bacteria, Escherichia coli and Salmonella species, using the culture methods of the applicable pharmacopoeial chapters or a validated qPCR equivalent. Products intended for inhalation are additionally screened for the pathogenic Aspergillus species — flavus, fumigatus, niger and terreus — because spores that are unremarkable on a surface behave differently when they are drawn into a lung.

Mycotoxins are the toxic metabolites certain moulds leave behind, and they persist after the mould itself is gone. Every batch of flower, and every extract made from flower, is tested for aflatoxins B1, B2, G1 and G2 and for ochratoxin A by LC-MS/MS.

Water activity measures the free water available to microorganisms and predicts microbial growth far better than moisture content does. Flower is released at a water activity at or below 0.65 aw, with moisture content typically between 10 and 12 per cent. Below that range the material becomes brittle and the terpenes are lost; above it, mould is a question of time rather than of chance.

10. Action limits, and what a pass looks like

For every safety analyte the certificate shows the measured result, the unit, the limit of quantification and the action limit that applied. A pass means every safety analyte sits below its action limit and the identity and potency results match the batch record. A result reported as ND, or as less than the limit of quantification, means the analyte was not detected above the level the method can reliably measure. It is not a guarantee of absolute absence.

Action limits are set to the strictest applicable value across the markets a batch is released to. A batch may therefore pass for one destination and be blocked for another. The storefront enforces that at checkout rather than at dispatch, so an order is stopped before payment rather than after packing.

Where a result sits close to a limit, measurement uncertainty is applied in the direction that does not favour release. A borderline result is treated as a failure until a fresh sample says otherwise.

11. Failed batches and out-of-specification results

A batch that fails any safety parameter is quarantined immediately and cannot be picked, sold or shipped. The block is applied in the inventory system, not by an instruction to staff.

An out-of-specification result is then investigated. It is first checked for laboratory error — instrument fault, sample mix-up, transcription error, contaminated glassware — and the laboratory's own investigation report is required before any result may be set aside. Repeat testing to obtain a better number, without a documented and identified cause for invalidating the first result, is not permitted. Testing into compliance is falsification, not retesting.

Where the failure is real, the batch is either remediated by a documented and validated process and fully retested from a fresh sample, or it is destroyed against a witnessed disposal record. Every failure is traced back to the harvest lot and forward to sibling batches from that lot, which are held pending their own results. If affected product has already reached customers, we recall it, notify the buyers of record by email, and inform the competent authority where the rules require it.

12. Retesting and shelf-life re-verification

Cannabinoids and terpenes degrade. THC oxidises slowly to CBN, terpenes evaporate, and the potency printed on a label drifts away from the potency in the jar. Testing is therefore tied to time as well as to release.

Any batch still in stock beyond its retest interval is re-sampled and re-tested for potency, water activity and microbial quality before it may be sold again. Stability is monitored on retained samples held under controlled temperature, humidity and light, and the retained sample for a batch is kept until [RETENTION PERIOD] after its best-before date, so that a later question can be answered against the actual material rather than against a memory of it.

Best-before dates are derived from stability data for the product type, not from a default interval. A re-tested batch carries an updated certificate of analysis, and the earlier certificate stays available, so the history of a batch is visible rather than overwritten.

13. Certificates of analysis and how to read one

A certificate of analysis is a laboratory's report on one sample from one batch. Every batch we release has one. It is published on the product page and linked from the batch code as soon as the batch is released for sale, and it stays online for as long as that batch may still be in a customer's hands, and for at least [COA RETENTION PERIOD] after that.

Read the header before the numbers. Check that the laboratory is named with its accreditation body and number, that the batch or lot code on the certificate matches the code on your package, and that the report is the current version and carries an authorised signature. A document without a batch code, an accredited laboratory and a date is not a certificate of analysis. It is a picture of one.

Then read the tables. Each safety analyte has a result, a unit, a limit of quantification, the action limit applied and a status. Watch the units: per cent by weight and milligrams per gram differ by a factor of ten, and milligrams per unit is not milligrams per gram. Ignore any rounded summary figure for total cannabinoids used in marketing material. The analyte table is the record.

• Laboratory name, address, accreditation body and accreditation number
• Sample identifier, batch or lot code, matrix, and the date the sample was received
• Test dates and the method reference used for each analyte
• Results with units, limits of quantification and the action limit applied
• A clear pass or fail per analyte group, and the overall release decision
• Report version, page numbering and the authorised signatory

14. Batch traceability and requesting the certificate for your order

Every unit carries a batch code. That code links backwards through packaging, testing and processing to a single harvest lot or manufacturing run, and forwards to the orders it was shipped in. Given a batch code we can identify the lot, its test reports, its release decision and its shipments. Given an order number we can identify the batches that were in it.

The batch code is printed on the label of every item and repeated on your dispatch note. It is also recorded against your order in your account, so the certificate can still be found after the packaging has gone in the bin.

If a certificate is missing, unreadable, out of date, or does not match the batch code on your package, write to quality@vitalleafrx.com with your order number and the batch code. We reply within five working days with the certificate for your specific batch. If we cannot produce it, you may return the item under the Returns and Refunds Policy. General questions about the testing programme also go to quality@vitalleafrx.com; formal notices go to legal@vitalleafrx.com.