How Plastic Quietly Became a Health Risk

Out of Mind out of Sight

We don’t usually think twice about plastic. We microwave leftovers in plastic containers. We drink bottled water. We unwrap food, toss the packaging, and move on.

But over the past few years, something uncomfortable has become clear: plastic doesn’t just disappear. It breaks down into microscopic fragments — and those fragments are ending up inside us.

Microplastics have now been found in human blood, lungs, placentas, and even brain tissue. And while this is still an emerging area of research, scientists are increasingly concerned about what chronic exposure to these particles is doing to our bodies.

So today, I want to break down three questions:

1. What exactly are microplastics, and how are they getting into us?

2. Why are researchers worried about their link to cancer and chronic disease?

3. And why something as common as microwaving plastic plays a bigger role than most people realize.

In the Body

Microplastics are tiny plastic particles — smaller than 5 millimeters — created when larger plastics degrade or when plastics shed fibers and fragments during everyday use.

They come from:

• Plastic food containers and packaging

• Bottled water

• Synthetic clothing fibers

• Plastic kitchenware and utensils

  
  

Once they exist, they don’t biodegrade. They persist in air, water, soil — and eventually, in us.

We inhale them. We ingest them. And unlike many toxins, our bodies don’t have an efficient way to break them down or remove them. That’s what makes microplastics fundamentally different from short-term chemical exposures.

Why Scientists Are Concerned About Cancer

Let’s be precise here: microplastics have not been officially declared a direct cause of cancer in humans.

But that doesn’t mean they’re harmless.

Microplastics have been shown to:

• Trigger chronic inflammation

• Cause oxidative stress

• Damage DNA

• Disrupt hormone signaling

  
  

Those mechanisms should sound familiar — because they are the same biological pathways involved in cancer development.

Recent studies have also found higher concentrations of microplastics in certain tumor tissues compared to healthy tissue. 

Everyday Behavior

This is where everyday behavior matters.

When plastic is heated — especially in a microwave — it doesn’t just get warm. It sheds. Studies show that heating plastic containers can release millions to billions of micro- and nano-plastic particles directly into food.

That means the food itself becomes a delivery system.

This is exactly the point highlighted in a recent Instagram reel by Paul Saladino, where he emphasizes avoiding plastic food containers during heating because heat accelerates plastic breakdown and exposure.

Important clarification: microwaving plastic is not “one of the leading causes of cancer” on its own. But it is one of the most controllable and repeatable ways people dramatically increase microplastic intake — often daily.

And over years? That adds up.