Lab Results

One With Tea is committed to transparency and purity. Founded by Christian Mauerer, a Naples, Florida-based importer who personally selects every supplier in Japan, the brand was built on one principle: no result, no release.

The U.S. matcha market generated $164.2 million in revenue in 2024 and is projected to reach $340 million by 2033, according to Grand View Research. As that market grows, so does the risk of adulterated or mislabeled products.

This page explains exactly what we test for, how we test it, and what every certification on our label actually means.

Why We Test Our Matcha Regularly

Key Facts:

• Third party tested matcha ensures lab-tested purity.
• Comprehensive screening covers heavy metal contamination, pesticide residues, microbial contaminants, and radiation.
• USDA Organic and JAS certifications guarantee organic matcha certification.
• Strict heavy metal testing minimizes lead exposure for a safe beverage.
• Complete chain-of-custody from tea plantations to the final beverage.

Our matcha undergoes third-party lab evaluation for heavy metals, pesticide residues, microbial contamination, and radiation before it reaches you.

The reason is simple and specific to matcha. Unlike brewed tea, where you steep and discard the leaves, matcha is made by whisking the entire powdered leaf into your drink. Any contaminants absorbed from the soil, including lead, cadmium, arsenic, and mercury, are fully consumed.

This process also keeps our USDA organic certification active, a standard managed by Quality Certification Services (QCS) through yearly audits. Our founder, Christian Mauerer, visits Japanese tea farms personally to verify authentic farming practices at the source.

Pro Tip: When evaluating any matcha brand, ask to see a Certificate of Analysis (COA) measured in parts per billion (ppb), not just parts per million (ppm). A ppb-level report reveals far more about trace metal content and is the standard used by serious independent labs.

Clean matcha powder matters most to those who prioritize transparency.

What We Test For

Our independent labs screen our batches against four core contaminant categories. Each category represents a real, documented risk in the global matcha supply chain.

Heavy Metals (Lead, Arsenic, Cadmium, Mercury)

Heavy metal testing is the most critical screen we run. Tea plants are hyperaccumulators, meaning they pull minerals and contaminants directly from the soil through their root systems.

Our labs use Inductively Coupled Plasma Mass Spectrometry (ICP-MS), the gold standard for this analysis.

Our batch is regularly confirmed to remain well below the official safety thresholds set by the FDA and the requirements of both USDA organic standards and the Japanese Agricultural Standard (JAS).

• Lead (Pb): A primary concern because tea plants absorb it from contaminated soils. Matcha is consumed whole, not steeped and discarded.
• Arsenic (As): Regulated with strict limits. Geographic location and proximity to industrial activity are key risk factors.
• Cadmium (Cd): Accumulates in soils from agricultural practices and is tightly regulated under both US and Japanese standards.
• Mercury (Hg): Controlled with very low tolerance levels due to its neurological toxicity at small doses.

With HS code 0902.10 guiding import compliance, we document all screenings to clear FDA prior notice. Our testing covers those who care about what goes into their cup, whether sipping ceremonial-grade matcha or using it in wellness supplements or toddler milk formulas.

On farms in Japan, we have seen firsthand how soil composition affects green teas, reinforcing why ongoing heavy metal screening matters for matcha purity testing.

Pesticide Residue Screening

After confirming heavy metal levels, we screen the batch for pesticide residues. This covers our USDA Organic Matcha Latte Powder, Strawberry Matcha Latte, and all other products in our line.

Pesticide residue testing is required for USDA organic certification and for JAS organic equivalency managed by Quality Certification Services.

To put the scope of this in perspective: according to AGQ Labs, a full organic compliance screen tests against up to 605 pesticide compounds, combining both the USDA National Organic Program (NOP) banned substance list and a broad conventional residue panel.

• Testing labs use methods including GC-MS and LC-MS/MS to detect pesticide residues at very low concentrations.
• We source directly from certified organic farms in Japan, reducing risk tied to agricultural practices that use synthetic pesticides or fertilizers.
• All documentation confirms compliance with both US and Japanese standards.

Wholesale buyers receive traceable lab results upon request. Passing these checks allows continued access to the US market while honoring Japanese matcha quality traditions.

Microbial Contamination

Microbial testing runs in parallel with every pesticide screen. Our tests cover bacteria, yeast, and mold to ensure each product meets FDA label compliance before release.

Direct farm relationships let us control post-harvest handling. Contaminated soil, poor drying conditions, or spoilage organisms like toxic mold can threaten product safety and nutrient quality in ways that no amount of organic certification will fix after the fact.

• We follow USDA organic audit standards by analyzing both loose leaf teas and powdered blends.
• Microbial analyses continue throughout storage and import to keep small-batch imports fresh.
• Periodic third-party tested matcha reports confirm our products are safe for all consumers, including toddlers who might drink matcha milk formulas.

Radiation Testing

The matcha we import is screened for radioactive materials by third-party labs before it leaves Japan or arrives in the United States.

We source from farms in Uji, Nishio, Shizuoka, Kagoshima, and Miyazaki. These regions sit hundreds of miles from the Fukushima Daiichi nuclear disaster site.

As a 2024 FDA review confirmed, after ten years of sampling Japanese food products, the agency found a very low risk to American consumers and deactivated its import alert.

Christian traveled through Japan's tea-producing areas to document traditional farming methods and witnessed the steps farmers take to preserve soil safety.

Radiation screening results are available to all wholesale partners and are part of our transparent documentation for customers seeking safe options in organic foods, matchas, gummies, and infant formulas.

How Our Testing Process Works

The batch moves through a documented, multi-stage process.

Third-Party Independent Labs

To ensure unbiased matcha lab results, we contract experienced independent laboratories that specialize in tea and botanical analysis.

• Reports are completed before every product release or certification renewal.
• Wholesale clients receive full documentation packages upon request.
• Only matcha that clears all benchmarks for heavy metals, pesticides, microbes, and radiation reaches our shelves as pesticide free matcha.

Interactive infographics and clear visual guides explain the lab testing process. Visual tools break down each stage from tea leaves in tea plantations to the final beverage and help you understand matcha heavy metals and pesticide screening.

Lab reports are available to anyone seeking extra assurance about their cup's purity.

From Farm to Final Product: Chain of Custody

We maintain a documented chain of custody from farm to final product. Christian travels to Japan and personally verifies every step, from matcha harvest through processing, export, import, and packaging.

1. Farm-level verification: Each batch is traced to a specific farm and harvest date using JAS documentation.
2. Export documentation: NOP import certificates are prepared before any product leaves Japan.
3. FDA prior notice: Every shipment follows FDA prior notice protocols as it moves to US distribution.
4. Storage and records: Clear records are maintained for both regulatory use and customer transparency.

This system supports full traceability on all our premium organic Japanese matcha tea products. Thorough chain of custody ensures heavy metal testing for lead, arsenic, cadmium, and mercury covers each stage before lab-tested purity reaches your cup.

Certifications Explained

Each certification on our label represents a real audit process, not a self-reported claim. Here is exactly what they cover and why they matter.

USDA Organic

USDA organic certification covers all our matcha and green teas, including Ceremonial Matcha Powder, Matcha Latte Powder, and Strawberry Matcha Latte. The USDA organic seal appears on every package and in our Shopify, TikTok and Amazon listings.

QCS manages this certification with yearly audits that include:

• Residue testing and Limit of Quantification checks on pesticide residues
• Heavy metal testing for lead and arsenic from soils
• Strict chain of custody documentation
• Prohibition on all synthetic pesticides, herbicides, and GMOs

To meet USDA standards under HS code 0902.10 for imports into the US market, we must confirm no synthetic substances appear in any certified product. Organic was the largest segment in the US matcha market in 2024, commanding a 64.31% revenue share according to Grand View Research.

All paperwork stays current and available for verification. Customers can see the difference compared to conventional Chinese green tea, which is often grown without these safeguards.

JAS (Japanese Agricultural Standard)

Our Japanese Agricultural Standard (JAS) organic status applies to every batch of Japanese matcha and tea we import. JAS certification goes beyond a label. It requires meeting strict limits on pesticide residue, heavy metals including lead and cadmium, and even radiation.

According to the Organic JAS framework established by Japan's Ministry of Agriculture, Forestry, and Fisheries, products carrying the JAS mark have been evaluated for quality, composition, soil management, and appropriate manufacturing processes.

Certification	Managed By	Key Requirements	Renewal Cycle
USDA Organic	QCS (Quality Certification Services)	No synthetic pesticides, herbicides, GMOs; annual audits; heavy metal and residue testing	Annual
JAS (Japanese Agricultural Standard)	Japanese Ministry of Agriculture, Forestry, and Fisheries	Soil management, pesticide limits, heavy metal limits, radiation monitoring	Annual (per Japanese regulatory cycle)

Every shipment from Japan arrives with full JAS documentation that satisfies both US authorities and wholesale customers who need complete traceability. Our farm partners follow all JAS protocols, from soil nutrients including zinc, right down to the final product.

How to Read Our Lab Reports

Each lab report is structured for clarity. You do not need a chemistry background to understand your results.

Every report includes:

• Product name and batch number for full traceability
• Test date and laboratory name that performed the analysis
• Category-specific results for heavy metal testing, pesticide screenings, microbial counts, and radiation levels
• Measured values vs. regulatory safety limits placed side by side for direct comparison
• Clear pass/fail status for required test on each batch

We organize digital documents by product and batch to keep traceability simple. If terms like lecithin, theobromine, or limit of quantification appear confusing in your report, our support team can walk you through the numbers.

One With Tea's Commitment to Transparency

Regular test results, certification, and sourcing detail is available for review before you buy.

According to a 2025 consumer research report by Salsify, 87% of shoppers will pay more for brands they trust. That statistic reflects exactly what we see in our own customer base: people who take their health seriously want proof, not promises.

Each batch of matcha comes with documentation that shows heavy metal testing for lead, arsenic, cadmium, and mercury. Lab reports include pesticide residue screening and microbial contamination checks.

Our approach stands out in the US matcha market where such transparency is rare. Having lived in Japan to study tea culture and quality shapes our mission to empower customers through facts instead of marketing language.

We focus on small-batch imports because this supports traceability from farm to cup while ensuring each product meets strict standards.

Every detail, including the flavor profiles influenced by purity testing, is open for informed decisions about what goes into your body.

FAQs

1. What is heavy metal testing in matcha, and why does it matter?

Heavy metal testing matcha products is essential because tea plants naturally absorb elements like lead and arsenic from the soil. We send our Japanese harvests to independent labs to ensure they fall safely below strict US regulatory limits.

2. How does One With Tea show its commitment to transparency?

Our founder visits farms in Japan's famous tea regions like Uji and Shizuoka, securing traceability from leaf to final cup with documentary evidence. We test our matcha batch for heavy metals, pesticides, microbes, and radiation using third-party labs to exceed CPSC guidelines. 

3. Does heavy metal testing affect the flavor of matcha?

Testing for contaminants has absolutely no impact on the smooth, umami flavor of your tea because the lab simply analyzes a small separate sample from each harvest.

 

Disclaimer: The information provided here is for informational purposes only and does not replace professional medical or nutritional advice.