Learn · Glaze safety

Is My Pottery Food Safe? What Every Buyer (and Potter) Should Know

By Christina Phillips, safety professional and potter · September 2026

It's the most common question potters hear at craft shows — and one of the most misunderstood. A beautiful glaze doesn't guarantee a safe one. Here's how to think about it, whether you make pottery or buy it.

What "food safe" actually means

A food-safe pot is one where the fired, finished surface won't release harmful substances into food or drink under normal use. That depends on three things: the glaze chemistry, whether it was fired correctly to maturity, and the condition of the surface. A glaze that is perfectly safe when formulated and fired as intended can become a problem if it's underfired, crazed, cracked, or badly damaged.

Lead and cadmium: the two metals to know

Lead has been used in glazes for centuries as a flux — it lowers the melting point and gives a brilliant gloss. Cadmium produces vivid reds, oranges, and yellows. In a properly formulated and fully fired glaze, these metals are locked into the glass matrix. But if the glaze is underfired, poorly formulated, or deteriorating, they can leach into food — especially acidic foods.

The FDA is blunt on this point: there is no safe level of lead exposure. Lead is especially dangerous for children and pregnant women, and its effects — including impacts on learning and development — can be permanent.

What the FDA actually requires

The FDA's Compliance Policy Guide (Sec. 545.450) sets the leaching levels at which it considers ceramic foodware to be in violation, measured in micrograms of lead per milliliter of leaching solution:

Two honest caveats. First, these are enforcement thresholds, not safety endorsements — below the action level doesn't mean zero risk. Second, enforcement is limited: imported ceramics are only sporadically tested, and the FDA doesn't routinely screen products already on store shelves. The burden falls on makers and buyers to ask questions.

Acidic foods make leaching worse

Tomato sauce, citrus juice, vinegar-based dressings, and other acidic foods accelerate the leaching of metals from a vulnerable glaze. A mug that's fine for water may not be fine for orange juice. Heat, long contact time, dishwasher abrasion, and thermal shock all add to the wear that can open the door to leaching.

5 questions to ask before you eat off it

1. 1.Was it made with food-safe-formulated glazes? Reputable glaze manufacturers label which of their glazes are formulated to be food safe when fired as directed. Ask the potter.
2. 2.Was it fired to the right temperature? An underfired glaze is the most common reason a "safe" recipe becomes unsafe. The maker's firing schedule matters.
3. 3.Is the surface intact? Crazing (fine cracks in the glaze), chips, and cracks aren't just cosmetic — they expose the clay body and create places for bacteria and leaching.
4. 4.Can the maker answer these questions? A potter who knows their clay, glaze, and firing schedule is a good sign. Vague answers are a red flag.
5. 5.Is it antique, vintage, or of unknown origin? Older ceramics were often made with lead glazes. When in doubt, use them for decoration — not dinner.

What about home lead test kits?

Those swabs you see online detect lead on the surface — they can't tell you whether lead will actually leach into food, or how much. A negative swab doesn't prove a glaze is safe, and a positive swab doesn't measure the real exposure. They're a rough screening tool, not a verdict. If you need certainty, laboratory leach testing is the standard.

The bottom line

Most modern studio pottery made with commercial food-safe glazes and fired correctly is perfectly fine to eat from. The risk lives in the unknowns: mystery glazes, underfiring, damaged surfaces, and vintage ware. Ask the questions, and when you can't get answers, err on the side of decoration.