Heavy Metals in Matcha: How to Check

A packet of matcha may be a beautiful green without telling you what is in that batch. If you're looking for data on heavy metals in matcha, first ask which substance was measured and in which sample. A published analysis doesn't automatically describe the powder you have at home.

We'd prefer a result tied to a batch over a general promise. Without one, the question remains open; its absence doesn't prove contamination. If you're asking because you felt unwell after a cup, possible reactions to matcha are a separate question from a contaminant measurement.

What do analyses of aluminum in matcha measure?

Matcha is drunk with the powder suspended in water. In 2024, a Bavarian analysis of 29 samples measured 330 to 2,661 mg of aluminum per kg of product. Carried out by the state office for health and food safety (LGL), it found an average of 1,149 mg/kg. These figures concern the samples studied. They give neither the content of another packet nor the number of milligrams absorbed from a bowl.

Keep the unit with the value. “mg/kg of powder” and “mg consumed” answer different questions. We wouldn't turn this range into a dose per cup without knowing the powder used and its own concentration.

Lacking data on actual consumption in Germany, the Bavarian assessment assumed one to three servings a day, made with about 1/2 to 1 tsp (1 to 2 g) of powder as the products indicated. Under those conditions, it expects no harm to health from aluminum for the 29 samples. This conclusion depends on those assumptions and those products; it covers neither heavier consumption nor another batch.

Is a concentration enough to judge risk?

No. The measured concentration, the weight of powder added, and how often you drink it all matter. Other sources of aluminum exposure may also contribute. A German assessment by the Federal Institute for Risk Assessment (BfR) covers three samples with high levels. It states that such a small number doesn't allow conclusions about typical aluminum levels in matcha.

We'd start with the weight actually used, because two bowls of the same size may hold different amounts of tea. Even if weighed, a cup doesn't give a numerical exposure when its batch's aluminum content is unknown. If you're asking how much matcha to drink daily, start with the amount in each bowl, without setting an aluminum threshold here.

What about lead or cadmium?

To investigate lead or cadmium, you need a measurement of the element in question. The publications cited here deal with aluminum; they give no value for the packet you're using. We prefer to say “content unknown for this batch” when no report is available to read. That means neither zero nor a demonstrated presence.

These elements are present in the environment. Soil, water or air can contain them, and the tea plant takes up part of them as it grows. An organic label governs how the tea is grown; it doesn't replace measuring a batch. Neither does the grade or the color. Our matchas come from Japanese producers certified to the Japan Agricultural Standard (JAS), on carefully chosen land. That choice matters, and it still doesn't replace analyzing a batch.

How do you read a matcha lab report?

Look for the batch number, the substance tested, the measured value, its unit, and the date. A screenshot that cuts off the unit or batch removes exactly what you need to interpret the number. We'd ask for the complete report; even that describes only the substances tested.

Also look at who carried out the analysis. A complete report names the laboratory and its method, then gives for each element a limit of quantification, the smallest amount the method can put a figure on. A result written, for example, as “< 0.01 mg/kg” falls below that limit without necessarily being zero. The uncertainty, shown as “±”, is a reminder that a measurement remains an estimate.

If a laboratory result worries you in your particular situation, have a health professional interpret it.