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What is plastic number 5 is it safe for babies

What is Plastic Number 5 (PP) and Is it Safe for Babies?

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Anyone out there looking to avoid plastic has a tough job on their hands – it’s everywhere! Since it’s nearly impossible to get rid of it completely, I thought I should explore which plastics are safe to use and which ones are dangerous for you and your baby. I’ve already covered the first four plastic numbers in previous articles, but today I’m looking at plastic number 5 (PP) to see what it is and check to see if babies are safe using it.

Plastic number 5 (Polypropylene or PP) is a thermoplastic polymer prized for its resistance to heat and fatigue (constant bending), strength, toughness, and flexibility. It is considered one of the safest plastics because it does not leach chemicals. It’s found in yogurt containers, baby bottles, and microwaveable kitchenware.

It’s good to know that we don’t have to worry constantly about every kind of plastic out there and number 5 plastic is one of the good ones. Let’s uncover what polypropylene is, where we will find it, and just how safe it is for babies.

What does plastic number 5 mean?

You’ve probably seen the numbers and triangular recycling symbol on the bottom of plastic containers a million times, but you might not know exactly what they mean.

Those plastic numbers are actually different categories of plastic and they help recyclers figure out what they are dealing with so they will know what to do with it. These resin identification codes (RIC), as they are called, are great because they can also help clue consumers into what exactly they are purchasing and using for their families.

Plastic items with a number 5 on them are made of polypropylene, or PP, which is a combination of propylene monomers and is petroleum-based. Aside from being strong and durable, it also works very well for living hinges (think about the flap on a package of Tic-Tacs) because of it’s resistance to fatigue. It’s frequently combined with other plastics to achieve different characteristics. It’s very stable and resistant to high temperatures, making it ideal for holding or heating hot foods.

The RIC codes that represent the plastic numbers are controlled by the American Society for Testing and Materials (ASTM International) and polypropylene fits into the fifth group. It is important to point out that even though these codes are commonly found on food packaging, they aren’t necessarily required to be listed on anything – they are there as a convenience for recyclers.

This means that you aren’t likely to find a code on certain items, especially large baby toys and accessories.

Examples of plastic number 5

Polypropylene is one of the most common plastics in the world. Since widespread adoption in 1957, it has found its way into packaging, equipment and electrical manufacturing, household appliances, and automotive. Today, there are about 55 million metric tons produced each year.

That’s a lot of plastic.

In general, you’ll find plastic number 5 in:

  • Living hinges
  • Straws
  • Medicine bottles
  • Kitchenware like Rubbermaid and Sterilite
  • Carpets
  • Ropes
  • Electrical wire insulation

Polypropylene is billed as being very safe for humans because it is unlikely to leach any chemicals into any food or beverages that it might hold. Additionally, its high heat resistance means that it’s frequently used in applications in which heat will be applied (such as the microwave). Even if it’s intended to be heated, I wouldn’t get into the habit of heating up plastic as a general rule.

The biggest problem with plastic number 5, as with many other plastics, is simply pollution. Very little polypropylene is currently recycled in the US and more is added to landfills each and every year. It’s also not biodegradable so that plastic will be sitting there for a very long time – hundreds or thousands of years.

Food containers made from polypropylene

Because of its food safety rating, heat resistance, and ability to bend back and forth repeatedly without breaking, you’ll find plastic number 5 all over the grocery store shelves. The coolest example is the so-called ‘living hinge’ that you’ll find on many condiment bottles and containers. They allow you to open and close a product without losing the lid!

Here are some other common examples:

  • Liners for things like cereal boxes
  • Yogurt and butter containers
  • Potato chip bags
  • Syrup bottles

Is plastic number 5 reusable?


Provided that the item is cleanable, you can reuse polypropylene many, many times. In fact, your grandmother has probably been using the same set of Tupperware for a few decades!

Baby products made from polypropylene

Other than some general products and uses, there are lots of baby-specific things that use plastic number 5. Here are a few examples:

  • Disposable diapers
  • Diaper pails
  • Baby food
  • Sippy cups and bottles
  • Toys

Like other plastics, polypropylene works extremely well when you need to keep moisture in check (diapers) or keep an object intact after a raging two-year-old gets ahold of it (toys).

This kind of plastic is impact-resistant, easy to clean, and strong. Once I started paying attention, I noticed that many of the sippy cups and child-themed utensils and accessories are made out of plastic number 5 (PP). We used this style of cup for years with my little girls and never had any problems with them breaking, cracking, or becoming deformed in the dishwasher. I never detected any ‘plasticky’ smell from them either.

Yes, I smell plastic.

Like I said before, this is very common because making food and beverage containers from polypropylene mean that they are probably dishwasher safe. Other plastics will melt in the dishwasher in a hurry!

Is plastic number 5 (PP) safe for babies?

You won’t have to worry too much about baby toys and accessories that include polypropylene because it’s such a stable plastic and doesn’t leach chemicals, even with warm or hot liquids being stored inside. Other plastics would have a definite problem being heated or even holding hot water inside.

I personally do not worry about my babies using drink cups, toys, or other accessories that are made from polypropylene.

In addition to its stability, number 5 plastic will also be BPA and phthalate-free because of how it’s produced. This fact should provide a lot of peace of mind, in and of itself, because those two chemicals are the real baddies of the plastic world. You should avoid them at all costs! Don’t worry if your container has ‘5’ or ‘PP’ on the bottom, even if it doesn’t say BPA free!

Can you microwave polypropylene?

This type of plastic is literally meant to be microwave-safe, so yes.

However, I personally do not microwave any plastic containers, no matter what the label says.

That could be me overreacting a little, but I think it’s a small price to pay for a little peace of mind. If you want to reheat leftovers, consider buying a nice set of glass storage containers for your kitchen. We use a set like these that we’ve had for many years. They are great because you can put them in the oven, the microwave, the fridge, or the freezer without having to worry about anything happening to your food (just take the top off first!).

If you are careful, they will last forever!

Can you recycle polypropylene?


Polypropylene can definitely be recycled, but you might not be able to do it with your curbside service because many facilities aren’t equipped to handle it. This trend is changing, but it’s estimated that less than 1 percent of this kind of plastic is recycled each year.

One percent.

In a landfill, this particular plastic will take 30 years to break down on its own. While new technologies are being developed to help increase the demand for PP recycling, it’s not here yet.

Finding alternatives to plastic for your baby

Polypropylene is generally safe to use both in the kitchen and in the baby’s room, but there are still lots of downsides.

Like I mentioned before, this plastic is by no means good for the environment as a whole and contributes a lot of extra waste in our landfills. Since they are also made from oil and gas, there are additional chemical by-products from these industries that add pollution to the air and increase carbon emissions. Overall, a lot is sacrificed for the convenience of plastic.

Avoiding plastic altogether is tough, but there are many options for substituting high-quality, long-lasting items for plastic in your home to avoid throwing away disposable plastic all of the time.

Stainless steel cups and utensils

Using stainless steel cups and utensils could be big news for you and your family. By adding stainless bottles, plates, sippy cups, spoons, and forks to your cabinets, you’ll have safe and effective kitchenware that can be used for a lifetime (or multiple lifetimes with more kids!). It will always be dishwasher safe and clean up easily – just don’t put it in the microwave!

Nowadays, there are a ton of options.

Here are a couple of my favorites:

  • Stainless steel divided trays – This set of metal trays have nice dividers to keep food from touching. Great for those picky eaters! They clean up fast and look great! stainless steel plateware
  • Stainless steel utensils – This cute cutlery set includes 4 each of rounded knives, forks, and spoons for your little one to use as she grows.
  • Pura Kiki Stainless steel infant bottle/sippy cups – This is a frequent recommendation of mine. This starter set is a nice value that gets you two of everything: stainless steel bottles, low flow nipples, medium flow nipples, sippy cup spouts, and travel lids. With this system, you can start things off right with the bottle and then work your way up as he grows!

Learn more about the other plastic numbers

I think we’ve covered all we need to know about plastic number 5, but there are seven plastic numbers in total. If you want to check out the next article in this series, check out the next article on plastic number 6. It’s one of the dangerous ones, so inform yourself!

Joshua Bartlett
Joshua Bartlett

My name is Joshua Bartlett I run this blog with my wife Jarah. We have more than 11 years of parenting experience including three girls and one boy. I started this blog in late 2018 when I realized that I was dealing with baby-related issues on a constant basis…please read more about me here!

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