INTRODUCTION
I personally enjoy working with clay every day and I would hate to see anybody be scared to work with clay. Over my years of pottery, I found clay to be a wonderful material. Children universally for thousands of years have safely enjoyed making artifacts with the clay in their villages. Hence, if clay is treated with respect and we use common sense, we can get all the fun and benefits of clay without risking our health. A lot of top-notch potters like to take risks in the design and content of their artwork, but when working with their materials and methods, they make enough effort to avoid any risk to their health and the health of their clients. All human actions involve some level of risk or danger. In that respect, yes, pottery can be dangerous. It carries a certain amount of risk.
Pottery clay is different from inelastic soil and fine sand because of its ability. When the clay is wet with the proper amount of water, it forms a solid figure and retains its shape when molded. This quality is said to be the clay’s plasticity. When heated at high temperatures, clay partially melts, resulting in the tight, hard rock-like substance known as a ceramic material.
Clay minerals such as kaolin, smectite, and palygorskite-sepiolite are part of the world’s most important and useful industrial minerals yet their care is not taken it might be hazardous to your health. The smectite component of clay has been proven by scientists that is it toxic especially if sniffed. That is why it is crucial for you to wear a face mask when you are working with clay. In addition, all materials-related health hazards take years of exposure to become a serious problem. You should take the risks seriously and know they are long-term.
TYPES OF CLAY
1. Earthenware Clay:
It is otherwise known as common clay, and it contains many minerals, such as iron oxide (rust), in its raw state may contain a bit of sand or small bits of rock. It is a little bit toxic when inhaled for too long. Because of its many impurities, it is harmful when inhaled or digested. Although, I do not believe anyone in his right senses will eat clay. Earthenware melts at a cooler temperature than other clays. We are going to talk more about this later in this article. Earthenware clay is said to be a low-fire clay because it bakes at a low temperature.
2. Mid-fire stoneware Clay
This is a tough and long-lasting clay that is fired to mid temperatures between 2100 and 2300°F (1205–1260°C). Mid-fire stoneware Clay’s natural colors vary from light and due to the color variations, researchers have found it a little bit toxic if ground and inhaled.
3. High-Fire stoneware clay
It will thrill you to know that the popular Kaolin you have heard and read is known as High-fire stoneware clay. Yes, Kaolin is another name for High-fire stoneware clay. Kaolin or China clay is the purest form of clay in the world. Due to this pre-undiluted form, it is toxic if ingested.
IS POTTERY GLAZE TOXIC?
As we all know, lead is hazardous to breathe, ingest (eat), and can be released from firing into the air. Any container glazed with lead may be toxic to eat or drink from because lead can leach into food or drink stored in the vessel. While new pottery sold today in the United States is generally assumed to be safe from lead, occasionally there are still cases of pottery that are unintentionally sold with dangerous amounts of lead in the glaze. Lead has many very serious effects if ingested. Lead can be absorbed from glazes by acidic food and drink.
Lead oxide is most times a red colorant. Since the white could be part of many tints, lead is very common in old paint. Lead has polluted soil around many long-standing houses where it has been washed down the siding by rain. Children with lead in their blood or system will have lower I.Q and other serious symptoms. Lead is not a pigment but is used to help the glaze melt, so it can be in a low-fire glaze of any shade. One should be especially cautious about old pottery and pottery purchased in countries while traveling.
TYPES OF GLAZE
1. Earthenware Lead-Free Glazes
This is designed to be food and drink safe and there are a large number of colors and special effects to satisfy all tastes. It contains minimal elements of lead, making it very safe to use to eat/drink. You can get yours by clicking here.
2. Earthenware Glazes Containing Fritted Lead
This type of glaze contains a significant amount of white and/or red lead. Thereby it will be toxic if used in the making of dinnerware. This type of glaze is mostly used to decorate and coat flower vases.
3. Stoneware & Mid-fire Glazes
All these glazes are very constant under both dissolving and reducing conditions. Many variations of color and properties can be produced by using different colored and stippled bodies. They contain minimal lead thereby it is a little bit safe. Most artworks coated in Stoneware glaze are dinnerware.
4. Raku Glazes
This is a Chinese type of glaze used on pieces like pots and pans. It is assumed that it does not contain any form of lead thereby making it the safest form of glaze out there.
| GLAZE | TOXICITY |
| Earthenware Lead-Free Glazes | NOT TOXIC |
| Earthenware Glazes Containing Fritted Lead | HIGHLY TOXIC |
| Stoneware & Mid-Fire Glazes | NOT TOXIC |
| Raku Glazes | NOT TOXIC |
SAFETY PRECAUTIONS
1. Keep yourself and your family safe:
You should keep young children out of your work area and far away from work clothes, supplies, brushes, stencils, glazes, or containers. Avoid eating or smoking in the pottery studio. Store glazes that contain lead safely.
2. Minimize your exposure to lead dust
In your studio, try as much as possible to reduce your exposure to lead dust by wearing a mask and working in a well-ventilated area. Your glazing and firing process should be at properly equipped institutions where the specialized equipment you need is properly vented.
3. Stay Clean
Make sure you clean all surfaces in your studio. Clean tools and equipment regularly by wet dusting.
In this article, I have talked about the toxicity of clay, the types of clay, how toxic glazes are, the types of glaze, and the safety precautions needed to minimize health risks.
