Are Mylar Bags Harmful or Safe?

When it comes to packaging, Mylar bags are a popular choice thanks to their durability and ability to keep products safe from moisture, air, and light. But if you’re using them for food storage or other sensitive items, you might be wondering: are Mylar bags toxic? It’s a valid question that comes up often, especially when it comes to the safety of long-term food storage.

In this blog, we’re going to clear up any confusion about Mylar bags and their safety. We’ll take a close look at what they’re made of, the myths surrounding them, and whether they’re really safe for storing food and other products. By the end, you’ll have all the facts you need to make informed decisions about using Mylar bags safely.

What Are Mylar Bags?

Mylar bags are a type of flexible packaging that’s become really popular for storing and protecting all kinds of products. You’ve probably seen them used for food storage, like dried foods or snacks, but they’re also commonly used for packaging electronics, medicines, and even some collectibles. The reason they’re so widely used is because they do a great job of keeping moisture, air, and light out three things that can spoil or damage products.

But what makes Mylar bags work so well? Let’s break it down.

Mylar bags are made from a material called PET (Polyethylene Terephthalate), which is a tough plastic film that provides a lot of strength and flexibility. On top of that, there’s a layer of aluminum foil, which acts as a barrier to light and oxygen—things that can cause food or other items to deteriorate. Finally, the inside layer of Mylar bags is usually a food-safe polymer, ensuring that the contents are protected and safe from any chemical reactions. This combination of materials gives Mylar bags their awesome ability to keep things fresh and secure.

Are Mylar Bags Toxic? The Short Answer

The short answer is no, Mylar bags are not toxic. High-quality, food storage Mylar bags are perfectly safe for storing food and other products. These bags are made with materials that have been thoroughly tested and certified by food safety regulators, including the FDA. In fact, Mylar bags are specifically designed to keep your food fresh by protecting it from air, moisture, and light, without any harmful chemicals leaching into the contents.

As long as you’re using food-grade Mylar bags and not cheap, low-quality alternatives, you can be confident that they’re safe to use for long-term food storage or packaging.

The Science Behind Mylar Bag Safety

Mylar bags are made up of several layers, each playing a key role in making them safe and effective for storage. Let’s break down the layers to understand why Mylar bags are safe to use:

Outer Layer (PET):

The outer layer of Mylar bags is made from PET (Polyethylene Terephthalate), a strong, flexible plastic that’s commonly used in food packaging. This layer is safe, durable, and resistant to heat and moisture. It provides the structure of the bag and helps protect the contents from physical damage, like punctures or tears, while also allowing the bags to be easily printed with branding or other information.

Middle Layer (Aluminum Foil):

The aluminum foil in the middle layer serves as a barrier against light, air, and moisture—three things that can spoil food and products over time. It’s non-reactive, which means it won’t interact with the contents inside the bag. This makes it a safe material for use in food storage and ensures that your items remain fresh and protected from environmental damage.

Inner Layer (Polypropylene):

The innermost layer of Mylar bags is made from polypropylene, a food-safe polymer. This layer is crucial because it’s the part of the bag that’s in direct contact with your food or products. Polypropylene is inert, meaning it doesn’t react with food, ensuring there’s no chemical contamination. It’s also heat-sealable, which is essential for creating airtight packaging that keeps your items fresh for longer.

Together, these layers make Mylar bags a safe and effective choice for packaging and storing food, ensuring that the contents stay protected and fresh without any risk of harmful reactions.

Common Myths About Mylar Bags: Fact vs. Fiction

There are a lot of myths floating around about Mylar bags, so let’s set the record straight and separate fact from fiction.

Myth 1: Mylar Leaches Harmful Chemicals into Food

Some people worry that Mylar bags might release harmful chemicals into food. The truth? Food-grade Mylar bags are perfectly safe. They’re made from materials that are tested and approved by food safety authorities, like the FDA. The inner lining of these bags is specifically designed to be non-reactive, which means it won’t break down or leak harmful chemicals into your food.

Myth 2: Mylar Bags Release Aluminum into Food

Another common concern is that the aluminum foil in Mylar bags could leach into food. But this is just a myth. The aluminum layer in Mylar bags never directly touches the food. Instead, it’s sandwiched between two other layers (the PET and the food-safe polymer lining), so it’s completely sealed off. This ensures that the aluminum stays safely away from your food.

Myth 3: Mylar Bags Are Unsafe When Exposed to Heat

People often think Mylar bags can’t handle heat, but that's not true. Mylar bags are actually heat-resistant, but like any material, they do have their limits. They’re perfect for things like storing food in cool, dry places. However, you should avoid subjecting them to direct heat for long periods, as that can weaken the seal or damage the bag. But don’t worry, they’re fine with normal storage conditions.

Myth 4: Mylar Bags Cause Food Contamination

Some people believe that Mylar bags might somehow cause contamination, but this simply isn’t the case. As long as you use high-quality, food-safe Mylar bags, they actually protect food from contamination by creating an airtight seal that prevents exposure to moisture, air, and light—three main causes of spoilage. If anything, Mylar bags help preserve food, rather than contaminate it.

When Can Mylar Bags Become Unsafe?

While Mylar bags are generally safe, there are a few situations where they can pose a risk. Let’s take a closer look at these potential issues and how to avoid them.

1. Poor-Quality or Counterfeit Bags

Not all Mylar bags are created equal. Low-quality or counterfeit bags can be a serious concern. Some manufacturers use non-food-grade materials that haven’t been tested for safety, which means they could release harmful chemicals or break down over time. Always make sure you're buying from a reputable supplier who guarantees that the bags are food-grade and safe for storing consumables.

2. Damaged or Creased Bags

Mylar bags are designed to be tough, but extreme handling or repeated folding can cause damage. If the bag gets creased or punctured, it may let in air or moisture, which can lead to spoilage of the contents inside. The risk here is not toxicity, but rather that the quality of the food could be compromised. So, it’s important to handle Mylar bags with care and avoid any physical damage.

3. Misuse of Non-Food-Grade Bags

Another risk comes from using Mylar bags intended for non-food applications, such as industrial or static shielding bags. These bags may not meet the same safety standards as food-grade Mylar bags, and using them for food storage can introduce harmful chemicals or contaminants. Always verify that the bags you choose are specifically marked as food-safe.

4. Storing Improper Foods

Mylar bags are best for storing dry foods with a moisture content of less than 10%. Storing wet foods or items with high oil content (like nuts or grains) in Mylar bags can lead to issues like rancidity or bacterial growth, especially if oxygen absorbers aren’t used properly. Always make sure you're storing foods that are appropriate for Mylar bags and use oxygen absorbers to create a proper seal.

The Importance of Using Certified, Food-Grade Bags

To avoid these risks, it’s crucial to use certified, food-grade Mylar bags. These bags are made with materials that are safe for food contact, have passed rigorous safety tests, and are designed to maintain the freshness of your items for long periods. Make sure to always check that the bags you purchase are BPA-free, FDA-approved, and intended for food storage.

Best Practices for Using Mylar Bags for Food Storage

Using Mylar bags for long-term food storage can be a great way to keep your food fresh for years. But to get the best results, it’s important to follow a few simple steps. Let’s break it down:

1. Properly Fill the Bags

When filling Mylar bags, don’t overfill them. Leave a little space at the top to make sealing easier and ensure an airtight closure. It’s also important to only store dry foods in Mylar bags. Foods with moisture, like fruits or oils, aren’t ideal because they can cause spoilage. Make sure your food is completely dry before packing it into the bags.

2. Use Oxygen Absorbers

One of the best ways to preserve the freshness of your food is by using oxygen absorbers. These little packets help remove oxygen from the bag, which can extend the shelf life of your food and prevent the growth of bacteria or mold. Make sure to use the right size oxygen absorber for the amount of food you’re storing—there are different sizes for different bag volumes.

3. Sealing the Bags

Sealing Mylar bags properly is key to keeping everything fresh. The best way to seal the bags is with a heat sealer, but if you don’t have one, you can also use a household iron or even a hair straightener! Just be sure the seal is tight and there’s no air left inside. For extra security, you can double-seal the bag, especially if you plan on storing it for several years.

4. Store in the Right Conditions

Once your Mylar bags are sealed, it’s important to store them properly. Keep them in a cool, dry, and dark place to avoid exposure to heat or light, which can damage the bags and affect the quality of your food. You can also store the bags in plastic bins or vacuum-sealed containers to add an extra layer of protection from moisture or pests.

Conclusion: Are Mylar Bags Toxic or Safe?

So, are Mylar bags toxic or safe? The answer is clear—Mylar bags are not toxic. When you use high-quality, food-grade Mylar bags, they’re perfectly safe for storing food and other products. These bags are made from materials that have been tested and approved for food safety, and when used properly, they’re an excellent choice for long-term storage.

It’s important to remember that the safety of Mylar bags depends on the quality of the bags you choose. Low-quality or counterfeit bags can be a risk, so always make sure you’re using certified, food-safe Mylar bags from trusted suppliers.

At Roylo Globe, we specialize in providing high-quality, food-safe Mylar bags that meet strict safety standards. Whether you're looking to store food, preserve valuables, or package products, we’re here to help you make the right choice for safe and effective packaging.