Can You Make Polymer Clay Food Safe?

What is polymer clay?

Polymer clay is a modeling and sculpting medium that is popular for arts, crafts, and DIY projects. Unlike normal clay that hardens when air dries, polymer clay requires baking at low temperatures to cure and harden. The term “polymer” refers to the plastic polymers used as a binding agent in the clay.

The main ingredients in polymer clay are:

• Plastic resin such as polyvinyl chloride (PVC)
• Plasticizers such as dioctyl phthalate (DOP) to keep the clay soft and pliable
• Fillers such as kaolin clay or calcium carbonate
• Color pigments

Additional ingredients may be added such as mica powder for shimmer effects. The ingredients are mixed together using an industrial process with machines that knead the material into a uniform clay polymer compound. This compound can then be shaped and molded when raw, and will permanently harden when baked in a regular kitchen oven at temperatures around 130°C/275°F. After baking, polymer clay is durable and can be sanded, drilled, and painted just like wood or ceramic.

Is polymer clay toxic?

Polymer clay is made from a plastic called polyvinyl chloride (PVC). The main ingredients in polymer clay are:

• Vinyl chloride monomer
• Plasticizers such as dioctyl phthalate (DOP)
• Color pigments

During the curing process, the vinyl chloride monomers combine through polymerization to form a solid plastic. However, not all the monomers react and some residual monomers may remain in the clay even after curing.

There has been concern that uncured polymer clay can leach chemicals like phthalates and vinyl chloride, which have been linked to health issues. Phthalates are known endocrine disruptors while vinyl chloride is a known carcinogen. Heating the clay, whether during curing or later during use, may increase the levels of chemical leaching.

FDA Regulations on Polymer Clay

The FDA (Food and Drug Administration) closely regulates and monitors the use of polymer clay for products that come into contact with food. Any polymer clay product intended for food use must meet strict requirements for being non-toxic and food safe.

Polymer clay cannot contain any hazardous materials like lead and must pass specific extraction tests to evaluate the migration of toxic elements into food. The FDA mandates compliance with safety standard CFR 21 part 109 which specifies permissible levels of lead, cadmium, mercury and other heavy metals.

Manufacturers must submit their polymer clay products to the FDA for testing and inspection. Through simulating real-world conditions, the FDA verifies that the polymer clay does not leach concerning levels of chemicals into food when heated, microwaved, or in contact over time.

Most major commercial polymer clay brands like Sculpey and Fimo have undergone this evaluation process and earned FDA approval. However, homemade or no-name polymer clay has not passed the required safety tests in most cases. Using untested polymer clay is risky for direct food contact and consumption.

Methods to make polymer clay food safe

There are a few methods that can be used to make polymer clay safe for food contact and consumption after proper preparation:

Baking/Curing Properly

Polymer clay must be fully cured according to the manufacturer’s instructions, which usually requires baking at 130°C/275°F for 15 minutes per 6mm of thickness. Properly curing the clay will stabilize the polymers and evaporate any residues.

Using Liquid Clay

Applying a layer of liquid clay, then curing can help create a smooth, non-porous surface. Liquid clay fills in any crevices where bacteria could lurk.

Sealing with Resin, Varnish, or Glaze

Coating cured polymer clay thoroughly with a water-safe resin, varnish, or glaze can prevent bacteria from growing in microscopic pores and provide a protective barrier.

Best practices for polymer clay food safety

When working with polymer clay for food-related items, it’s essential to follow proper safety guidelines. Here are some best practices to ensure your clay creations are food-safe:

Proper baking instructions: Always follow the manufacturer’s instructions for baking polymer clay. Pieces must be fully cured at the proper temperature and duration to harden the clay and make it non-toxic. Underbaked clay can potentially leach chemicals.

Recommended glazes/sealants: After baking the clay, additional coatings can provide an impermeable barrier for food safety. Opt for glazes, varnishes or sealants specially formulated for clay use. Avoid paints containing lead, cadmium or other toxic pigments. Allow any finishes to fully cure before use.

Quality ingredients: Purchase polymer clay from reputable brands that disclose ingredients. Avoid cheap clays that may contain higher levels of plasticizers, heavy metals or contaminants. For direct food contact, use clays made specifically for that purpose.

By carefully controlling the clay ingredients, baking thoroughly, and adding food-safe sealants, crafters can create beautiful, durable polymer clay items that are suitable for food use.

Risks of Using Non-Food Safe Polymer Clay

Using polymer clay that is not food safe for projects involving food or drink comes with potential health risks that should not be ignored.

Many polymer clay products contain chemicals likephthalates and heavy metals that can leach out of the clay, especially when heated. Phthalates are endocrine disruptors that can negatively impact hormones and the reproductive system. Heavy metals like lead, cadmium and antimony are toxic and have been linked to cancer and organ damage with long-term exposure.

These harmful chemicals can transfer from the polymer clay into food and beverages when used improperly for cups, plates, bowls and other serving dishes. The risk increases when polymer clay comes into contact with acidic foods and drinks that can more readily leach chemicals from the clay.

In addition to health risks, using non-food safe polymer clays can also impact the taste and smell of foods. Chemicals leaching into the food can leave unpleasant odors and flavors behind that ruin the eating experience.

For these reasons, non-food safe polymer clay should never be used to create bakeware, dinnerware, utensils or anything else intended to come into direct contact with food or drinks for serving. Polymer clay labeled as food safe should always be used for these types of projects to limit potential harm.

Suitable Polymer Clay Projects for Food

While polymer clay is not food safe in its raw form, with the proper sealing methods it can be used for some food-related projects that do not involve direct contact with food. Some of the most common suitable uses of polymer clay for food items include:

Jewelry – Polymer clay jewelry such as beads, pendants, and earrings can make beautiful and unique additions to your table settings. As long as they are properly sealed, polymer clay jewelry pieces are considered safe for use around food.

Decorative Bowls, Plates, and Mugs – Polymer clay can be sculpted into stunning decorative bowls, plates, and mugs. As long as a food-safe sealer like resin is used, these items are safe for holding and serving food, even though the clay itself remains porous.

Non-Cooking Utensils – Polymer clay utensils like butter knives, spreader sticks, and spoon rests are suitable for tabletop use after sealing. Since they don’t involve direct food contact or heat, sealed polymer clay utensils can make charming decorative additions to a table setting or kitchen.

The key for all polymer clay food projects is proper sealing with a food-safe product. As long as the clay itself does not come in contact with food during use, sealed polymer clay items are generally considered safe in food-related applications.

Unsuitable polymer clay food projects

While polymer clay can be made food safe with proper sealing, there are certain types of polymer clay projects that should always be avoided for direct food contact.

Polymer clay cooking utensils like spoons, spatulas, and mixing bowls should never be used. The clay could start to soften and leach chemicals when exposed to heat from stovetops or ovens. Even if sealed properly, there is too much risk of the polymer clay degrading during prolonged heat exposure when used as cooking tools.

Baking pans, muffin tins, and other polymer clay bakeware are also unsuitable for actual baking. The direct heat from ovens can potentially cause chemicals in the clay to leach through any sealants. Polymer clay also runs the risk of softening and deforming when exposed to baking temperatures for extended periods.

In general, any polymer clay items with direct and sustained contact with food or heat should be avoided. Things like drinking cups, plates, and servers have a strong chance of degrading over time, especially if washed frequently. The porous nature of polymer clay makes it prone to absorbing liquids and oils that can break down the material.

For these reasons, polymer clay is best suited for decorative food items rather than functional cooking utensils or dishes. Care should be taken to use polymer clay for display foods only, not anything involving direct food or heat contact for consumption.

Alternatives to polymer clay for food

While regular polymer clay is not food-safe, there are some good alternatives if you want to use modeling clay for food-related projects:

Sculpey III – This is a dedicated clay made by Sculpey that is certified non-toxic and specifically designed for baking and food use. It comes in a variety of colors and can be hardened in a regular oven.

Resin – Two-part resin like epoxy resin can be used to coat polymer clay to seal it and make food-safe. The resin provides a protective barrier between the clay and food.

Food-safe glazes – Certain ceramic glazes rated food-safe can be applied to cured polymer clay pieces to create a non-porous surface for food use. Be sure to use lead-free glazes specifically made for this purpose.

Testing clays and sealants is recommended to ensure they do not interact with foods. Proper baking and curing is also key to food safety. While regular polymer clays pose risks, the right materials can allow clay food projects safely.

Conclusion

In summary, polymer clay can potentially leach toxic chemicals and cause health issues if used improperly with food. The main concerns are phthalates and lead that may not be fully polymerized during baking. While the FDA does not approve polymer clay as food safe, steps can be taken to reduce risk such as thorough baking and sealing. The safest option is to avoid polymer clay with acidic or fatty foods and use alternate materials where suitable. For low-risk foods, polymer clay can be used if properly prepared. Test batches before serving and inform consumers. Ultimately, exercise caution when deciding which polymer clay projects are appropriate around food.

The key recommendations are to thoroughly research and test any polymer clay item before allowing food contact, use high-quality clays and sealants, display awareness of risks, and seek alternate materials if safety is uncertain. While polymer clay can produce beautiful and creative works, food safety should take priority.