Lab Testing Explained: How to Read a Certificate of Analysis

A Certificate of Analysis (CoA) is the document a third-party laboratory issues describing what they tested, what they found, and how it compares against thresholds for safety and quality. For kratom, it's the consumer's main mechanism for verifying that a product matches its labelling. This article walks through what's in a CoA and how to read one.

The honest disclaimer up front: lab testing tells you what was true about that batch, at that point in time. It doesn't tell you about the batch in the bag you bought a year later, or about the next batch the same vendor produces. It's a snapshot.

What a CoA is, and what it isn’t

A CoA should be issued by an accredited lab. Most top tier Kratom manufacturers also run their own tests regardless of CoAs from upstream suppliers. The vendor sends a sample from a specific batch to the lab; the lab tests it; the lab issues a document with the results. The credibility of the document depends on the lab being independent and accredited (typically ISO 17025).

What a CoA does tell you:

• Whether the tested sample was free of dangerous contaminants at the limits of the tests used
• What the alkaloid profile of the tested sample was
• Whether the labelled strain matches the alkaloid signature you'd expect

What a CoA can't tell you:

• Anything about the next batch the vendor will sell
• Anything about how the product was stored or handled after testing

Heavy metals

Heavy metals are a significant risk in any plant-derived product because plants accumulate metals from soil. The four routinely tested for are:

• Lead (Pb) — cumulative neurological toxin. No level is "good" — lower is always better. California Prop 65 sets a daily exposure threshold of 0.5 µg/day; the FDA's tolerable intake for supplements is similar. Look for results well below 0.5 ppm in finished product.
• Arsenic (As) — inorganic arsenic in particular is the concern. Look for total arsenic below 1.5 ppm; ideally with the results showing predominantly organic forms.
• Cadmium (Cd) — long-term kidney concern. Look for results below 0.5 ppm.
• Mercury (Hg) — less commonly elevated in kratom but tested for completeness. Look for results below 0.5 ppm.

"Below the limit of quantification" (BLQ or "ND" for Not Detected) is what you want to see for most of these on a clean batch. Trace amounts within the thresholds above are acceptable; results above them shouldn't be.

Microbial contaminants

Kratom is dried plant material processed and packaged in tropical environments — microbial contamination is a real risk if the supply chain isn't controlled. Standard tests:

• Salmonella — must be absent. Any positive test is a failed batch. The 2018 multi-state Salmonella outbreak linked to kratom is the reason this test is non-negotiable.
• E. coli — must be absent for pathogenic strains. Total coliforms below specified limits.
• Total yeast and mould — below industry-standard limits (commonly <10,000 CFU/g, with stricter limits in finished products).
• Total aerobic bacterial count — a general microbiological cleanliness measure.

If a CoA omits Salmonella and E. coli testing, that's a meaningful gap. These are the tests directly relevant to consumer safety.

Alkaloid content

This is the section that tells you whether the product is what the label says it is. Two specific alkaloids matter most:

• Mitragynine (MIT) — the dominant alkaloid in raw leaf. Typical concentration in good leaf is around 1.0–1.8% by weight. Higher concentrations (1.5–2%+) usually indicate quality leaf or selected lots; concentrations below 1% suggest weaker or older material.
• 7-Hydroxymitragynine (7-OH) — a minor alkaloid in raw leaf, typically at 0.01–0.05% by weight. Significantly higher than this suggests adulteration with synthetic 7-OH or a misleadingly labelled extract.

This is part of why kratom.com sells whole-leaf and full-spectrum extracts only and does not sell isolated 7-OH or synthetic alkaloids — the leaf's natural ratio is meaningful, and concentrating one alkaloid out of context produces a meaningfully different product, with a meaningfully different regulatory and safety profile.

Reading a CoA for an extract

Extracts intentionally have higher alkaloid concentrations than raw leaf. A full-spectrum water-extract CoA might show mitragynine in the range of 5–20% by weight, with 7-OH proportionally elevated but still in roughly the same ratio to mitragynine as the source leaf.

What you don't want to see in an extract CoA:

• 7-OH concentrations that are massively out of proportion to mitragynine — suggests isolated or synthetic 7-OH was added
• Solvent residues if the vendor claims water-extraction — a clean water-extract CoA should show no detectable ethanol, methanol, or other solvents
• Missing or absent alkaloid quantification

Is the lab itself credible?

The CoA is only as good as the lab that issued it. Quick checks:

• Is the lab name printed on the document?
• Is it ISO 17025 accredited?
• Does it test botanicals or supplements as a regular practice (some labs primarily test cannabis or food products and have less kratom-specific expertise)?

Established kratom-experienced labs include Eurofins, Tagne, ABC Testing, and others. A vendor who is consistently using a recognised independent lab is likely operating with a high bar.

Batch numbers and traceability

The most important piece of operational information on a CoA is the batch or lot number. That number should appear on:

• The CoA itself
• The product packaging you received
• The vendor's online CoA library

If those three numbers don't match, it's difficult to verify that the CoA you're looking at corresponds to the product you bought. Vendors that take batch traceability seriously make this trivial: scan a code on the bag, see the CoA for that exact batch.

A practical CoA checklist

When you're looking at a CoA for the first time, look for:

• Independent third-party lab name
• ISO 17025 accreditation indicator
• Date of testing
• Batch / lot number that matches the product you have
• Heavy metals: lead, arsenic, cadmium, mercury — all present, all below thresholds
• Microbial: Salmonella absent, E. coli absent, yeast/mould within limits
• Alkaloid quantification: mitragynine % and 7-OH %
• For extracts: solvent residue panel showing absence of relevant solvents

If a vendor's published CoA is missing any of these, ask them about it. The answer is informative either way.