Article published on 29 May 2026.

Heavy metals, such as lead, cadmium, arsenic, and mercury, occur naturally in the soil. Any plant grown in open ground absorbs some of these metals—including tea, vegetables, grains, coffee, and cocoa. Traces of these metals are therefore found in virtually all teas, and matcha is no exception. No matcha has zero traces of these metals, and that would be impossible anyway.

What matters, therefore, is not their presence, but their level, and the ability to measure it accurately.

Where do the heavy metals in matcha come from?

Heavy metals are neither additives nor treatment products: they are a natural part of the environment. Found naturally in rocks and soil, they are absorbed by plant roots as the plants grow.

The tea plant follows the same principle as spinach, rice, or cocoa, which are among the crops most affected. This is a characteristic of open-field farming, not something unique to matcha.

Why matcha deserves a closer look

Matcha has a unique characteristic: it isn't brewed; instead, you consume the whole leaf, which has been ground into a powder. So everything found in the leaf is also found in the matcha you drink.

That's what makes laboratory analysis far more meaningful than a logo on the packaging: it measures what the finished product actually contains.

What really matters is the dose

What determines exposure to a heavy metal is not its concentration in a food, but the amount actually consumed.

However, matcha is typically consumed in very small quantities—about 2 grams of powder per bowl. A few comparisons can help put these quantities into perspective.

Regarding mercury: our matcha contains less than 0.01 µg per bowl. A piece of tuna sushi contains about 4.5 µg—the equivalent of nearly 500 bowls. A can of tuna is the equivalent of 2,600 bowls of matcha.

As for lead: our matcha contains about 0.19 µg per bowl. A serving of a few squares of dark chocolate (about 30 g) contains roughly 30 times that amount.

Our results

Our matcha is tested by Eurofins Dr. Specht, a world-renowned laboratory specialising in tea. Here are the results for heavy metals (test conducted on 21 April 2026; 2025 harvest sold in 2026).

Independent, open-access analyses

Our matcha is tested by an independent laboratory, and we publish the results in the spirit of full transparency. You can view the complete test results:

In our view, this is the only real answer on the subject of heavy metals: measured, accessible figures rather than a claim on the packaging.

How to Choose a High-Quality Matcha

Before making a purchase, there are a few simple questions you can ask to evaluate a brand. See if it can clearly tell you:

• where the matcha comes from and who produces it,
• whether it undergoes independent testing,
• if these analyses do indeed focus on heavy metals,
• if the results are recent and available.

A reputable brand must be able to answer these questions. If the answer is vague, it often says a lot about the brand as a whole.

Conclusion

Heavy metals come from the soil: they are found in all foods grown in open fields, including matcha. What sets a product apart, therefore, is not an impossible-to-achieve absence of these metals, but the actual measured level, the exposure this represents when calculated per serving, and the brand’s transparency regarding its test results.

Sources

Lead in Tea — FSA / Fera, “Analyses of Lead Levels in Tea” (FS102115, 2015): 51 teas, ranging from 0.125 to 2.56 mg/kg.

Mercury and Fish — ANSES, “Methylmercury: A Health Risk Associated with High Fish Consumption.”

Tolerable Weekly Intake for methylmercury (1.3 µg/kg body weight) — EFSA, Scientific Opinion on Mercury and Methylmercury in Food (2012).

Cadmium, limit for leafy vegetables (0.20 mg/kg) — Regulation (EU) 2023/915.

Mercury in tea, limit 0.02 mg/kg — Regulation (EC) No. 396/2005.

Nickel, content in cocoa powder (~10.7 mg/kg on average) — Food Safety, Luxembourg (nickel fact sheet).