Heavy Metals in Methylene Blue and Everyday Products — What You Need to Know

If you've ever checked the ingredients or lab reports on supplements or health products, you may have noticed references to “heavy metals.” It might sound alarming, but trace amounts of heavy metals are present in many everyday products — including natural supplements, food, and even tap water.

So what does this mean for methylene blue? Let’s unpack what heavy metals are, how much is considered safe, and what to look for when choosing a methylene blue product.

What Are Heavy Metals?

Heavy metals are naturally occurring elements like:

Lead (Pb)
Arsenic (As)
Mercury (Hg)
Cadmium (Cd)

While these elements are toxic at high levels, they are found in trace amounts in soil, water, plants, and animals — and therefore in many of the things we consume daily.

Who Sets the Safety Standards?

To ensure consumer safety, the United States Pharmacopeia (USP) has established strict daily intake limits for elemental impurities in pharmaceutical products, detailed in USP <232> and <233>. These limits are designed to:

Protect sensitive populations
Prevent chronic exposure
Account for cumulative intake from all sources

USP Permitted Daily Exposure (PDE) Limits for Oral Use:

Heavy Metal	Daily Limit
Lead	5 µg
Arsenic	15 µg
Mercury	15 µg
Cadmium	5 µg

These levels are based on total daily exposure, not just from a single product.

Where Else Are Heavy Metals Found?

Even if you don’t take supplements, you’re exposed to trace metals through:

🍚 Rice & grains (may absorb arsenic from soil)
🐟 Fish (especially tuna, swordfish – contain methylmercury)
🍼 Baby food (has come under FDA scrutiny for lead and arsenic)
🍫 Dark chocolate (sometimes contains cadmium and lead)
🚰 Tap water (municipal sources may contain trace lead)

What About Methylene Blue?

We take safety seriously. That’s why we third-party test our methylene blue with accredited labs using USP <233> methods.

✅ In our most recent Certificate of Analysis, we tested a 5 mg dose of our methylene blue and found:

Heavy Metal	Amount per 5 mg Dose	USP Daily Limit	Status
Lead	0.47 µg	5 µg	✅ Compliant
Arsenic	0.005 µg	15 µg	✅ Compliant
Mercury	0.01 µg	15 µg	✅ Compliant
Cadmium	0.066 µg	5 µg	✅ Compliant

Should You Be Worried?

No — not if you're choosing quality-tested products. Heavy metal testing isn’t about eliminating them entirely (which is nearly impossible), but ensuring they remain far below the threshold that could cause harm.

When you see transparency, third-party testing, and USP compliance — that’s a good sign. We share our test results openly, and you can always request raw data from us.