Is #5 (Polypropylene) Really Safe? The Rising Evidence on Microplastics & Health

This very common plastic is everywhere.

It’s used in food containers, toys, medical devices, automotive parts, etc., if you see a hard plastic, it’s probably polypropylene.

While we know it’s almost impossible to completely stop using plastics, there are some practical steps we use in our own lives to dramatically reduce the use of them.

Either way, we’re here to tell the truth about this plastic commonly deemed “safe” — and in another article, we’ll explore which plastics truly are safer options

So let’s get into it.

TL;DR

Is Polypropylene Safe?

While polypropylene is BPA-free and often deemed safe, this plastic, along with all other plastics, leach microplastics into the air and the food that it touches over time, especially when heated. While research on how microplastics affect our health is still new, recent studies show microplastics, even polypropylene, can stimulate our immune system, giving us reason to believe they are possibly harmful. Aside from polypropylene’s direct effect on humans, it is toxic to our environment due to its energy-intensive production, non-biodegradability, and low recycling rate.

What Is Polypropylene

Polypropylene, also known as “PP” and often identified by the resin identification code labeled “PP5,” is a type of plastic that can be used in many ways.

Of the seven categories of plastics, polypropylene, or number 5, is the second most used behind polyethylene (PE).

Polypropylene is widely used because it’s so versatile.

It’s light but strong, has high resistance to heat and various chemicals, has excellent insulating properties, and is cheap to produce.

Polypropylene Examples In Everyday Life

When we first started cutting down our plastic use, we were shocked to discover how often polypropylene showed up — from the kitchen to the bathroom, and just about everywhere in between:

• Plastic Bottles: ex. condiments bottles, shaker bottles, shampoo bottles, etc.
• Food Containers like Tupperware
• Rugs and carpets
• Toys
• Auto Parts: the console, door panels, bumper, etc.
• Medical equipment: syringes, IV tubing, etc.

Is Polypropylene Toxic?

While polypropylene is BPA-free, we don’t consider any plastics safe, especially ones that touch our food.

Why?

A few reasons.

Polypropylene’s Effect on Health

• Polypropylene, like all plastics, leaches microplastics into your food, especially when heated.
• As plastic wears down over time, it leaches even more microplastics into the surrounding air (and any food it touches).
• One study showed that high concentrations of polypropylene microplastics stimulates the immune system (and not in a good way).
• Another study notes how microplastics are small enough to get inside our cells and possibly disrupt their function but more research is needed to examine if this is true.
• A 2025 Nature Medicine study found micro- and nanoplastics—including polypropylene—in human liver, kidney, and brain, with higher levels in brains of people with dementia.

We are still in the early days of finding out how much of a danger microplastics are to our health, but one thing for sure is it isn’t exactly “healthy”.

And while the debate about whether microplastics are harmful to us continues, no one debates its negative effect on the environment.

Impact on The Environment

Here are the key reasons why polypropylene (and all plastic) is harmful to the environment:

• Production Impact: The production process of polypropylene has been proven to be very energy-intensive .
• Non-Biodegradable: Polypropylene lasts in the environment for very long periods of time.
• Microplastics Formation: Over time, polypropylene products break down into microplastics, tiny particles that are harmful to wildlife and can enter the food chain.
• Low Recycling Rate: Although polypropylene is recyclable, its recycling rates are very low. Many electronics and large items contain polypropylene in various parts, making them harder to separate and recycle compared to something like a simple plastic bottle.
• Toxic Emissions: When burned, polypropylene emits harmful gases into the atmosphere.

Keeping It Real- A Balanced Perspective

While we suggest reducing your plastic use, we are not saying all plastic should be banned.

We recognize that plastic including polypropylene plays a crucial role in places like the medical and automotive fields.

Our goal isn’t to completely eliminate it, but to cut it back in non-essential areas where more sustainable alternatives are easily accessible.

Sustainable Alternatives to Polypropylene

For every polypropylene product, there exists a more sustainable alternative.

For instance, we store our food using containers like glass, stainless steel, silicone, and wax paper.

Here are some other tips to limit polypropylene and other plastics alike:

• Choose natural materials whenever possible. Pick toys, utensils, and household goods made from wood, stainless steel, bamboo, natural rubber, or organic cotton instead of plastic.
• Shop smarter. Buy in bulk or from refill stores to minimize packaging waste. Bring your own containers, cloth bags, and jars
• Be heat-smart. Avoid heating food in any type of plastic container—use glass or ceramic for microwaving or reheating.
• Pick rugs and carpets made from wool, jute, sisal, or cotton rather than synthetic fibers that shed microplastics.
• Invest in longevity. When replacing household items, choose quality over quantity—durable natural materials cost more upfront but last much longer.
• Avoid as much food packaging as possible and learn to cook from scratch
• Also, try not to throw out your plastic containers, but rather repurpose them!

Until next time! Thanks for reading!