Used in products ranging from BPA-free water bottles to silicone molds and more, this tough and pliable material is made without Bisphenol-A, a dangerous chemical that's common to plastics. Let's do a deep dive into silicone and look at why it's far superior to BPA plastic, answering some common questions like “What does BPA free mean?”
Silicone 101
A non-toxic polymer, food-grade silicone is largely made from silica, also known as silicon dioxide (SiO2), a naturally occurring compound that's composed of silicon (Si) and oxygen (O2). You find silicon dioxide almost everywhere on the planet — in water, the ground, plants, and in animals. It's in the quartz sand on the beautiful beaches we love, is most of the material in common rocks, and silicon dioxide makes up nearly 60% of the earth's crust. It's even in us; the tissues of human bodies have naturally occurring silicon dioxide.
Silicon Dioxide in Foods
We know that silicon dioxide is safe for food-related products because it's already in a lot of the healthy foods that we eat. Brown rice, oats, beets, and leafy green vegetables (just to name a few foods) all contain natural silicon dioxide. Plus it's also widely used as a food additive, popular for its anti-caking properties, which are particularly useful when making food supplements; silicon dioxide prevents powdered materials from sticking together. As you may have assumed, silicon dioxide is determined to be safe by the U.S. Food and Drug Administration.
Are silicon and silicone different?
Yes, and not just because one of the words has an "e" on the end of it. With no "e," the word silicon refers to the basic naturally occurring element (Si). Silicone, however, is the word that applies to the wide spectrum of synthetic substances that contain silicon, which is rarely found on its own in nature. Silicon bonds easily with oxygen and so it more commonly occurs as silicon dioxide, aka silica.
What is BPA and why should I worry about it?
You may wonder — what does BPA stand for? Short for Bisphenol-A, BPA is an industrial-grade chemical that's been used in the production of plastics and various resins since the dawn of the plastic industry boom in the 1950s. One of its greatest dangers to consumers lies in packaging, namely the BPA in plastic water bottles and a variety of food containers such as the linings of metal cans. This BPA can, and does, seep into the food and beverages inside the packaging. And the science on this is settled: BPA is bad.
How bad? BPA studies stretching back decades have shown that BPA is linked to pregnancy loss, and can have a negative impact on developing fetuses, responsible for different placental diseases, affecting the prostate glands and brains of unborn children. After birth, the problems continue with a range of behavioral issues attributed to BPA. These include hyperactivity, depression, aggression, and higher than normal levels of anxiety. Research has also suggested links between BPA and cardiovascular disease, type 2 diabetes, and high blood pressure in adults.
All BPA-Free Products Are Not Equal
BPA-free means you’re safe, right? Not so fast. You might want to be wary of BPA-free plastics. You may come across a plastic product in a store that's labeled BPA-free and assume that it's safe since it doesn't contain the dangerous chemical. But maybe not. The BPA substitutes that manufacturers of plastics use can be just as harmful to human health.
What is Bisphenol-A getting replaced with? As the evidence of the dangers of BPA have become more clear over the past decade, some manufacturers have moved to substitute BPA with BPS: Bisphenol S. But this close cousin of BPA may be even worse! Studies on BPS have shown that it can have serious detrimental effects on human health, and may be linked to obesity issues, reproductive defects, and even cancer.
How is silicone made?
Making silicone begins with sand. Quartz sand, to be exact, which is largely made up of silicon dioxide. Often in huge amounts, quartz sand is heated to temperatures as high as 3,000 degrees Fahrenheit, similar to the way you make glass. This heating leaves you with pure silicon, which is ground into a fine powder after it cools. The silicon powder is then combined with the organic compound chloromethane and heated again, creating a mix of compounds.
This is done with machines that are often referred to as "dough mixers" — the process of making silicone has been likened to making a cake or crafting bread from scratch. The process continues with a delicate balancing act of distillation, separating different components in the mix by heating it at different temperatures. The end result is silicone.
Silicone Stands Up to Pressure
Heat? Not a problem. Cold? Bring it on! Silicone is strong, made to take on extreme temperatures, beyond heat of 200 degrees Fahrenheit and down to around minus 80 degrees Farenheit without succumbing to deforming. All without the hazardous off-gassing or leaching of dangerous chemicals — often the problem when plastics are subjected to extreme temperatures. You may have experienced this if you've ever left plastic in a hot car; that acrid smell you notice is off-gassing.
Easy-to-clean silicone products such as silicone baking mats can go from the freezer to the dishwasher without fear of damage. Plus silicone is pliable, flexible enough to take twists, squeezes, pulls, drops, and even some smashing without getting knocked permanently out of shape. Add in hypoallergenic qualities, stain- and odor-resistant properties and you've got a material that's superior to plastic in a host of different ways.
Silicone Products Are All Around Us
How do we use silicone in our everyday lives? Well, that's a long list! Silicone uses include adhesives, lubricants, sealants, electrical insulation, and much more. But perhaps the best use of silicone is with silicone molds for food — oven-safe, microwave-safe, freezer-safe, and a wonderful way to form foods to your exact desires.
Now that you understand the true BPA-free meaning, the wise choice is to steer clear of Bisphenol-A; BPA is best left in the past. Instead, look to the future of silicone and gummy molds.
