Ceramic safety in the U.S. Is measured with a 4% acetic acid leach test, basically strong vinegar against glaze. It has a way of telling the truth that a glossy surface can hide.
That simple fact collides with a popular search query: are handmade mugs food safe. The truthful answer lives in glaze chemistry, not marketing copy. Fired to cone 6, about 2232°F, a silica-rich glaze can lock up metals tightly. But underfire it by 50°F, or pair it with a clay that encourages crazing, and acids find pathways. Sounds fussy. It is. So how do you tell, before you sip?
Here’s the honest guide I wish more potters published, pulled from studio tests and failure notes at Fernwick Pottery Studio. And yes, we’ll talk about lab standards and the at-home tells that actually matter. No scare tactics. Just what studio data and glaze formulas actually say. Bring your curiosity and your favorite mug.
What “Food‑Safe” Really Means for Handmade Mugs
Food-safe has two parts that must both be true. First, the surface touching food is intact and not porous, no crazing or exposed clay. Second, the glaze shows low risk of harmful leaching under acidic conditions. Think chemistry plus surface integrity, working together.
So what do all those labels actually mean?
| Term | What it means | About chemistry? | Durability/use signal |
|---|---|---|---|
| Food-safe | Low leach risk on intact surfaces | Yes | Implies safe for contact |
| Dinnerware-safe | Smooth area where food touches, no texture traps | Partly | Often a studio promise |
| Dishwasher-safe | Withstands cycles without damage | No | Mechanical and thermal durability |
| Microwave-safe | No arcing, spalling, or overheating | No | Heat tolerance, not leach proof |
In the U.S., most functional studios avoid lead in glazes, especially since the 1990s. But “lead-free” doesn’t equal safe in every body and firing combo. Copper greens or manganese blacks can still leach if underfired, crazed, or unbalanced, as any potter reading the Seattle Pottery Supply guide on food‑safe glazes learns. And glaze chemistry folks keep reminding us that “no lead” isn’t a free pass, it’s glaze stability that matters per this Ceramic Materials Workshop explainer.
What changes outcomes over time? Layered glazes that create interfacial mismatch. Underfiring or overfiring that shifts melt. Crackle and crazing that open highways for acids. Coffee, tea, and tomato are repeat offenders, especially hot and left standing see this practical checklist. Still think a glossy mug can’t leach?
Glaze Chemistry, Plainly: Why a Stable Glass Surface Matters
Glaze is a thin glass fused to the pot. Silica builds the network; fluxes drop the melt point; alumina adds viscosity and lasting strength. At maturity the glaze bonds to clay, making a vitrified, low-absorption skin that resists coffee and tomato acids see this practical checklist. Miss the window, behavior shifts. What does maturity look like in practice? Clue by clue.
And the core ingredients are simple.
- Fluxes: Na, K, Ca, B; they melt silica at the chosen cone.
- Alumina: adds kiln viscosity and strength on cooling.
Here’s a quick walk-through of low-fire versus high-fire, plus what “dinnerware-safe” means.
| Firing state | Visual cues | Risks | Notes |
|---|---|---|---|
| Underfired | Matte when meant glossy, pinholes, powdery | Leaching, staining, crazing in acids | Short on flux or heatwork |
| Mature | Even gloss or tight satin | Low absorption, strong bond | Match clay and schedule |
| Overfired | Runs, thins, bare rims | Exposed clay, weak edges | Too much heatwork, trapped bubbles |
Vitrified Clay + Glaze Fit: How the Body, Glaze System Affects Safety
A mature stoneware body is tight. At cone 6 to 7, good recipes hit under 1% water absorption, which blocks wicking and odors, plus freeze-thaw damage, and supports hygiene for food contact. That density resists sourdough acids and coffee tannins, and it’s why cleanup stays easy. So what actually locks in long-term cleanliness?
But glaze fit decides the story after the kiln cools. A mismatch in thermal expansion creates two failures that matter.
| Fit issue | What you see | Safety impact | Typical cause |
|---|---|---|---|
| Crazing | Fine crackle lines that darken with tea | Higher surface area, stain and odor traps, can raise leaching in unstable glazes | Glaze expands more than clay |
| Shivering | Razor-like flakes at rims or edges | Flaking and sharp chips; exposed clay | Clay expands more than glaze |
Practical checkpoints makers use, drawn from clear studio guides and consumer-focused advice:
- Surface integrity: no pinholes, crawling, bare spots, or rough patches. Fully glazed interiors. Smooth, rounded rims.
- Glaze stability: passes vinegar or lemon-slice sit tests; no matte-to-gloss change or off-odors after contact.
Studio stress tests keep it honest. Fernwick Pottery Studio targets under 0.5, 1.0% body absorption, runs the ice, boil cycle, then inspects under bright light. And mugs go through repeated dishwasher and microwave runs, with a loupe check for new craze lines. Sensible. Backed by materials-first teaching.
A Buyer’s Checklist for Safe, Everyday Stoneware Online
Shopping online hides the tactile clues you rely on in person. So treat product pages like lab notes. What should they actually say?
Start simple. Compare claims with what they must imply.
| Claim | What it must mean online |
|---|---|
| Lead-free | A clear statement that finished pieces are suitable for food contact, not just a materials note. |
| Food-safe glaze | Stability on this clay body, firing range, and any glaze layering documented; a material label alone isn't proof (practical studio guidance). |
| Vitrified stoneware | Low absorption listed, often under 1 to 2 percent, with firing maturity noted, like cone 6 or 10 (consumer checks). |
And then look hard at the details.
- Scan photos for fully glazed interiors, smooth rims, and clean surfaces without pits, pinholes, or visible craze lines.
- Skip intentional crackle on food-contact areas, especially mug interiors.
- Ask about glaze layering and fit on that specific clay body, plus simple acid tests the maker runs.
- Read care policies; dishwasher and microwave guidance signal how the surface holds up in real use (care examples).
- Trust signals matter: maker transparency, testing notes, and references to reputable education.
Fernwick Safety Notes: Materials, Firing, and How We Evaluate Glazes
Materials and firing
Fernwick Pottery Studio fires stoneware to maturity, targeting under 1, 2 percent absorption at cone 6, 10 consumer checks. No intentionally added lead in any food-contact glaze, aligned with current lead and glaze safety context. Why does that matter? Stable bodies and glassy surfaces resist leaching and staining practical studio guidance.
- Glaze approach: stable base recipes; no intentional crackle inside; smooth, well-melted finishes.
- Fit and finish: fully glazed interiors and lips; we cull pinholes, crawling, and craze lines before listing.
Our food-contact claims rest on these practices.
| Test | Pass if |
|---|---|
| Thermal cycling, ice to boil, ×10 | No new craze lines or dunting; sheen unchanged |
| Utensil-mark and 24 h acidic soak | Minimal marks; no matte bloom or color bleed |
Batch notes record clay, glaze, and firing schedules by date. And our quarterly glaze-of-the-season cards state why each surface suits food contact. If we run third-party leach tests, we'll note it on the product page.
Care and Use for Longevity (Without Confusing Durability with Safety)
Dishwasher or sink? Both are fine for most stoneware, but hand-washing cuts long-term abrasion on matte or satin finishes, which can haze over time care guide insights. Avoid thermal shock. Don’t move a chilled mug straight into a microwave or pour boiling water into a fridge-cold bowl.
| Topic | OK? | Notes |
|---|---|---|
| Dishwasher | Yes | Top rack preferred; avoid gritty detergents on satin/matte. |
| Hand-wash | Yes | Soft sponge, mild soap; skip scouring pads. |
| Microwave | Yes, if no metallic luster | Never microwave metallic-luster surfaces. |
| Fridge to microwave | No | Let it warm at room temp first. |
- Acidic or salty liquids are harsher; wipe or rinse after use to cut contact time studio guidance.
- Stains: try a gentle baking soda paste or a diluted vinegar soak, then rinse well; dry fully before storing.
- See new craze lines, rim chips, or lingering odors? Retire the piece or contact Fernwick Pottery Studio.
Are Handmade Mugs Truly Food Safe? See Proof
Fernwick Pottery Studio formulates silica rich, cone 6 glazes and batch tests with the 4 percent acetic acid leach standard. Shop handmade mugs that lock up metals and publish safety results with every release.
Free returns and safety report link included
Frequently Asked Questions
Are handmade mugs food safe under glaze chemistry standards?
Many are, if the glaze is mature and leach-tested. ISO 6486-1:2019 and ASTM C738 set strict lead and cadmium limits. Worth asking for test data.
What firing temperature matters most for leaching risk?
Underfired glazes at cone 5 or 6 can leach more. But by cone 10, a well-fitted silica-alumina glaze resists acids; crazing from mismatch still invites trouble. Fit between glaze and body matters.
How can makers or buyers check safety at home?
Vinegar or lemon tests hint, but they don't quantify. So send a sample for ICP-MS per ISO 6486, or run a 4% acetic acid, 24-hour soak at 22 C; why guess?
Do colorants like copper or cobalt raise concerns?
Copper above ~3% in low-silica matte cone 6 glazes can leach. And cobalt is often tighter in the glass network, yet acids and salts still pull ions, so recipe and firing matter.
Sources
- A safety question, I see beautiful mugs and dinnerware here that has ..., People often wrongly think if all glazes used are food safe, it is food safe. The reason this is not true is because alone one glaze may be ...What makes food-safe ceramics for dishes and mugs? - FacebookHow to make safe ceramic mugs for use - FacebookMore results from www.facebook.com
- How to Tell If Pottery Is Food Safe?, The term “food-safe” has two components: the fired glaze finishing of the ceramic pieces and the amount of heavy metals that have the potential to leak into ...
- Food safe glazes: how can you tell if your pottery will be food safe?, Skip to Main Content
There has been a lot of chatter recently about food-safe glazes and how to tell if a piece of pottery will be food safe. Generally, a piece of pottery is considered food safe when it meets the following criteria:
- Surfaces that come into direct contact with food or drink must be fired to their full maturity so the clay particles vitrify enough to form a waterproof surface _or_ be covered by a smooth, glassy glaze without cracks or rough spots that could allow food to penetrate through the glaze to the clay body. Note that even when fired, low-fire clay remains porous enough that fluids may penetrate the surface and soak into the clay. Any surface that comes in contact with food or drink on pieces made from low-fire clays must therefore be covered with a food-safe glaze that has been correctly fired.
- Any glaze that comes in contact with food needs to be chemically sound and not leach metal oxides into the food. It is a good best practice to use a transparent or white liner glaze that you know does not contain any harmful elements on the inside of any piece meant to be used with food or drink. Glazes whose surfaces are heavily crystallized or overly melted (runny), brightly colored (without a clear overglaze), or very matte, are the most likely to be unsuitable for food.
Chemical Stability of Glazes
Chemical stability is also very important to food safety. Although a ceramic glaze is considered a glass, it actually can dissolve over time when in contact with liquids if it's not chemically stable. If a glaze contains metal oxide colorants such as barium, lithium, or lead, these compounds can then dissolve into food or drink, especially in the case of acidic foods like lemon juice or coffee.
If the glaze does not contain enough silica there is a good chance a stable glass has not been formed. It is also important to notice high percentages of oxides like BaO, MnO, PbO, or Li2O, which have the potential to leach. High percentages of these oxides or a low percentage of silica would be obvious in the recipe and should warn you that the glaze may not be suitable for food ware.
The absolute limits for all oxides (to prevent leaching) are hard to establish, as glaze chemistry is much more complex than that of regular glass. Still, there is value in being aware of obvious chemistry irregularities like large amounts of metal oxides. In general, any recipe that uses more than 3% of any metal oxide should be tested for leaching before being considered food safe.
Glaze Crazing and Food Safety
Crazing is often seen as an interesting visual element, but from a food safety point of view, crazed ware is unacceptable. Crazing can severely weaken a piece and provide space where water can enter and saturate the clay if it's not completely vitrified. The cracks may also harbor bacteria if not sanitized regularly. Crazing happens when glazes are under tension because the clay and the glaze have different shrinkage rates. Simple awareness of crazing is a strong measure anyone can take to improve the safety of the ware they produce.
Of course, it is worth noting that even though crazing is considered not food-safe, people have been using crazed wares for centuries without experiencing negative health issues. There have even been scientific studies that show that as long as you wash pieces with crazed surfaces with soap they are just as healthy as non-crazed glazes. That said, if you have crazing, it is always a best practice to add a glossy, clear food-safe liner glaze over the food surfaces.
How to test if a glaze is food safe
There are a few easy tests that anyone can perform to test if a glaze is chemically sound.
A simple visual inspection will reveal crazing or shivering. If a piece of functional ware is used and put in the dishwasher every day crazing will almost certainly appear if the glaze is under stress. By placing a piece in ice water, then in boiling water repeatedly, you can reveal if these problems will happen over time from thermal shock.
A simple lemon test can also be performed to test if a glaze will leach over time:
- Squeeze the juice of one lemon and put one slice of the lemon onto a horizontal, glazed surface and leave it out overnight.
- The next morning, remove the lemon and rinse the piece. If you see or feel any change in the color of the glaze, this indicates that the acid in the lemon juice was able to leach other materials out of the fired glaze.
If a glaze that fails this test were to be used for functional work, like a cup of coffee, the acid in the coffee could cause similar leaching of unwanted and potentially hazardous materials. If your glaze fails this test, don’t use it on functional work.
It’s important to note that if your glaze passes this test, it doesn’t necessarily mean that materials aren’t leaching out of the glaze at all, just that they aren’t leaching badly. If ever in doubt, use a clear or white liner glaze on all surfaces that will come into contact with food and drink, and save any questionable glazes for the outside of your work. Seattlepotterysupply.com
- Chill Out, It's Just Lead: A Sensible Look at Glaze Safety, # Chill Out, It’s Just Lead: A Sensible Look at Glaze Safety
Handmade and small-batch functional ceramics made in the United States do not use lead in their production.
This practice has been in place for decades, ensuring that your handcrafted mugs, bowls, and plates are lead-free and safe for everyday use.
Even major dinnerware companies in the US, like Fiestaware, stopped using lead in their products way back in 1986.
It’s all about how it’s used and, most importantly, how much actually leaches out into your food or drink.
Mythbusters: Debunking the Lead Scare
- Myth: All ceramic glazes, especially handmade ones, contain dangerous levels of lead.
- Fact: Handmade and small-batch functional ceramics produced in the United States have largely eliminated lead from their production processes. This has been the standard for decades, ensuring safer pottery for everyday use.
FDA Regulations: Keeping You Safe
- Flatware (plates, bowls): 3 milligrams per liter (mg/L).
- Holloware (Bowls): Slightly lower limits than flatware.
- Cups, mugs, pitchers: 0.5 mg/L.
Why the Difference in Limits?
The varying limits reflect the duration of contact between food/drinks and the ceramic surface.
Knowledge is Power: Your Takeaways
- Modern manufacturing and strict regulations have significantly mitigated lead risks in US-made ceramics.
Success!
CMW is on YouTube!
- New questions on glazes and food safety - Forums, # New questions on glazes and food safety
Recommended Posts
terraforma
Posted July 15, 2012
First question: I'd like the simplest and most straightforward explanation of food-safe and non-food-safe glazes—an explanation that those who purchase my ceramics will understand. I want them to understand, but I don't want to scare them off if I have a piece with a non-food-safe glaze. I never use these kinds of glazes on anything intended for food, but I may make a bowl that could, for example, hold fruit.
Question two: it seems to me that whole bananas, oranges, avocados, etc. Would not pose any problems just sitting in a bowl with non-food-safe glaze.There don't seem to be leaching issues. Right or possibly wrong?
Guest JBaymore
First question: I'd like the simplest and most straightforward explanation of food-safe and non-food-safe glazes—an explanation that those who purchase my ceramics will understand. I never use these kinds of glazes on anything intended for food, but I may make a bowl that could, for example, hold fruit.
Question two: it seems to me that whole bananas, oranges, avocados, etc. Would not pose any problems just sitting in a bowl with non-food-safe glaze.There don't seem to be leaching issues.
As a bowl that looks like a functional bowl, food function is implied to any person who might see or purchase it. Therfore, uless there is a FIRED ON label (non-removable) "not for food service use" ....... You have a potential problem there.
NO... A banana sitting is such a bowl is not an issue.... But the above factor is.
The simple answer to the first one is simply the statement "food -safe". But be sure it IS when you make such claims.
There has been a lot of discussion of this subject on these forums and a lot of info already posted.
For the two actually regulated oxides in glazes in the USA (lead and cadmium), see the FDA website and the State of California websites. If you use lead or cadmium compounds there are laws that you need to comply with. Best,
TJR
Terraforma;
If you are making any type of functional pottery and selling it to the public, you should not be using non-food safe glazes as in lead glazes.John is correct as always-cadmium is not safe, nor is barium carbonate.
I make stoneware and porcelain pots, so chances are pretty good that the glazes are safe. I avoid all lead glazes.Many commercial low-fire glazes in jars may be labelled not food safe.
There is that old story about the boy who made a mug for his dad in art class and gave it to him for Father's Day. The dad drank a cup of Coke-a Cola out of his pottery mug every night. Turns out the mug was glazed with lead and the dad got lead poisoning.I also avoid the purchase of mugs from Mexico, as many of the glazes involve car batteries.You can't be too careful.
Marcia Selsor
Toggle Quote On 7/15/2012 at 8:36 PM, TJR said:
Terraforma;
If you are making any type of functional pottery and selling it to the public, you should not be using non-food safe glazes as in lead glazes.John is correct as always-cadmium is not safe, nor is barium carbonate.
I make stoneware and porcelain pots, so chances are pretty good that the glazes are safe. I avoid all lead glazes.Many commercial low-fire glazes in jars may be labelled not food safe. I would stay away from them.
There is that old story about the boy who made a mug for his dad in art class and gave it to him for Father's Day. The dad drank a cup of Coke-a Cola out of his pottery mug every night. Turns out the mug was glazed with lead and the dad got lead poisoning.I also avoid the purchase of mugs from Mexico, as many of the glazes involve car batteries.You can't be too careful.
TJR.The dad recovered.
So when you daughter or grand children use this fruit bowl for lemonade punch and it leaches. You won't be around to tell them oops ? you can't control what buyers will use a bowl for.DO NOT USE toxic chemicals for anything that can potentially hold food.
yedrow
Posted July 16, 2012
Toggle Quote On 7/15/2012 at 7:40 PM, JBaymore said:
First question: I'd like the simplest and most straightforward explanation of food-safe and non-food-safe glazes—an explanation that those who purchase my ceramics will understand. I want them to understand, but I don't want to scare them off if I have a piece with a non-food-safe glaze. I never use these kinds of glazes on anything intended for food, but I may make a bowl that could, for example, hold fruit. This leads to...
Question two: it seems to me that whole bananas, oranges, avocados, etc. Would not pose any problems just sitting in a bowl with non-food-safe glaze.There don't seem to be leaching issues. Right or possibly wrong?
When the bowl leaves your hands, you cannot control the way the consumer uses it. As a bowl that looks like a functional bowl, food function is implied to any person who might see or purchase it.
This is an excellent point, if I may help by emphasizing it.
Posted July 16, 2012
The "Mastering Cone 6 Glazes," is a great book. There are interstitial cavities and exposed 3d surfaces that exaggerate the effects of acids and bases on the glaze: Caustic fluids have more access to surface constituents. Ron and John also point out that not only will your food leech out, but the pot will discolor from alkalies in the dishwasher or even acid rain.
Raku
I never use these kinds of glazes on anything intended for food, but I may make a bowl that could, for example, hold fruit.
Question two: it seems to me that whole bananas, oranges, avocados, etc. Would not pose any problems just sitting in a bowl with non-food-safe glaze.There don't seem to be leaching issues. Right or possibly wrong?
Maybe another question you should be asking is, "How do you know what the customer will use the bowl for" maybe use only food safe in all items which COULD be used for food. Maybe the Fruit bowl for examle, might be used for Salad.
Important Information
- Caring for your Ceramics - The Kind Earth Witch, This is by far the most asked question, and we completely get it! 100%.
I always get asked if mugs and ceramics are dishwasher safe and the answer is- no.
The insides of ceramics have glaze on them, and glaze is more than just paint. When fired to the right temperature, glaze basically forms a fine layer of glass over the raw clay, making it food safe and liquid resistant.
This is also that reason why some glazes and firing strategies are not considered food safe, even when they are glazed.
Not only can water and moisture get into the clay but the chemicals in the clay can leech out into food or drinks over periods of time.
The answer is yes, pottery is microwave and even oven safe. All of the pottery on this site has been fired up to cone 6 (^6) which is 2200 degrees F (1200 degrees C) or higher.
You’ll know it because its SUPER shinny and normally made of metals like gold, silver or bronze.
It will also retain heat longer than glass so if you are using it to cook (A pie plate, brei cooker, ect) be aware of this so that your food doesn’t get over cooked.
- What makes food-safe ceramics for dishes and mugs? - Facebook, For food-safe ceramics, both base and glaze must be safe, and vitrified clay with low absorption rate is key to prevent water soaking.How to test if handmade clay cups are food safe?How to make safe ceramic mugs for useMore results from www.facebook.com
- How to Tell If Pottery Is Food Safe?, # How to Tell If Pottery Is Food Safe?
_Updated 2024_
This is not the case anymore. Paints and glazes are now heavily regulated for lead and cadmium content, especially those that will be directly in contact with food.
The United States Food and Drug Administration (FDA) closely monitors trace amounts of lead and cadmium in crockery. Makers must guarantee their products never go above a set safety standard, to be allowed to sell their products in the US. These pieces are categorized as cadmium and lead-safe.
You probably noticed that it doesn’t say lead-free but lead-safe, and there is a reason for that. Even if all the materials and associated processes used to make pottery are lead- and cadmium-free, there is always a chance for naturally occurring heavy metals to be present in trace amounts. This means there is no such thing as 100% lead-free ceramics.
However, you can certainly find pottery that is non-toxic and perfectly safe for everyday use.
How to tell if pottery is food safe?
The term “food-safe” has two components: the fired glaze finishing of the ceramic pieces and the amount of heavy metals that have the potential to leak into your food if the glaze coating is broken.
The FDA performs leach testing to classify pottery dishware as food safe. Even if the glaze contained lead or cadmium before firing the piece, it can still be marked as food safe if it meets the FDA standards. The maximum allowable tolerance for lead contamination in food wares can be viewed here and the maximum allowable tolerance for cadmium contamination in food wares can be viewed here. Read more about determining if pottery is food safe on the U.S. Food and Drug Administration website here.
It’s important to note that food-safe and non-toxic are two different certifications and are not interchangeable. While food-safe is a regulated designation of finished pottery which grants the use for human food consumption, non-toxic refers only to the absence of known human toxins and is not regulated.
Here are some things you can look out for when purchasing your home’s pottery dishware.
Watch out for imported pottery
You should always be wary of imported ceramics. This is especially true if they come from South America or Asia, and if they display particularly colorful and bright designs.
As noted above, lead makes the paint and glazing brighter and gives ceramic products a beautiful glossy finish. Even if these lead-based materials are no longer allowed in the U.S., they might still do so in countries where regulations are not as progressive.
However, you don’t have to test everything. What is one easy way to know how to tell if pottery is food safe? Plain white dishes rarely test positive for lead making them a very low risk.
1 How to Tell If Pottery Is Food Safe? 2
Thanks to readily available non-toxic dyes and color pigments, Emerson Creek is able to craft brightly colored glazes, like our American Blue pictured above, which easily exceed both FDA regulations and California Prop 65 requirements.
Other characteristics that make pottery food safe
Besides being lead-safe, there are other things to consider when buying food-safe pottery. These include being chip-resistant, microwave-safe, oven-safe, and dishwasher-safe. These features make the pieces very durable, and the glaze won’t break or crack easily, minimizing the potential for lead exposure.
Reducing your family’s exposure to lead from ceramic cook- and dinner-ware
When food-safe ceramic dishware is used normally, the probability of food being exposed to these heavy metals is extremely low. But, if acidic foods are stored for long periods in porous containers, the amount of dangerous substances leaching into the food can reach harmful levels.
A good way to minimize exposure is not to use pottery that you are unsure about.
As you are determining how to tell if pottery is food safe, if you don’t know if a piece is food-safe, the safest option is not to use it for everyday meals or drinks. This is particularly important for children, nursing mothers, and pregnant women, as they are more susceptible to the consequences of lead poisoning.
Buying pottery made in the United States is another way to ensure it’s compliant with FDA regulations.
If you want to feel even safer, buy ceramics that are compliant with California Proposition 65. The Golden State has gone above and beyond by establishing the strictest regulation ceramic serveware. Read more about how ceramics and tableware are directly regulated by California Proposition 65 on the California Department of Health website here.
Don’t use items that might have a high leaching potential to heat food or drinks. Heat exposure, be it via microwave or stove, accelerates the leaching process.
Don’t use the dishwasher unless you are sure it is dishwasher-safe like all Emerson Creek Pottery is. The machine could damage the glazed surface and increase the probability of leaching. It can also cause cross-contamination of other dishware.
Don’t store food or drinks for long periods in ceramic containers, especially if what you are saving is acidic. Some examples of acidic food include tomatoes, citrus fruits, apples, soy sauce, fruit juices, soft drinks, coffee, tea, and alcoholic drinks.
Never use crockery with corroded glaze or if you notice a grayish residue on the glaze after washing it. These damages increase the probability of the heavy metal leaching into your food.
Carefully select pottery to avoid hazardous materials. Emerson Creek pottery allows you to achieve safety while creating a unique table setting. Emerson Creek in your home instills peace of mind.
8 Responses
- Hi Steve! Thanks for your comment. We believe the food-safe designation applies to all foods, not just foods with liquids. Log in to Reply
- Drinking hot coffee from a glazed frankoma brand mug from the 1967 is probably a bad idea it sounds like. Is there really no point to test lead content for an item like that?
- It really depends on what you want to do. If the mug is one of your favorites and makes you happy to drink out of it, it could be worth testing the lead content because there’s always a chance that it could be non-toxic. But more likely than not it contains toxins. Log in to Reply
- What is the maximum content of Lead and Cadmium content accepted by FDA and under what norm or standard ?
- Hi Efren! Thanks for your comment. Here are a few documents that will answer your questions. [https://www.fda.gov/media/71764/download](https://www.fda.gov/media/71764/download) [https://www.fda.gov/media/71762/download](https://www.fda.gov/media/71762/download) Log in to Reply
- Hi Gail! All of our pottery, whether it is intended for food or other household use, is nontoxic and lead-safe. All of our products are safe to use with food. You can also put any piece of Emerson Creek Pottery in the microwave, dishwasher, or oven. Hope this helps! Log in to Reply
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