Is Polyurethane Toxic? Everything You Need To Know

Polyurethane is a versatile and durable synthetic polymer used in a variety of applications, from furniture and bedding to clothing and footwear. But with its widespread use, concerns have been raised about the safety and toxicity of polyurethane. In this article, we’ll explore everything you need to know about polyurethane and its potential toxicity, so you can make informed decisions about the products you use.

Polyurethane comes from two main ingredients: isocyanates and polyols. Isocyanates are highly reactive chemicals that can cause allergic reactions, asthma, and even cancer. Polyols are less reactive, but can still cause skin irritation.

When isocyanates and polyols react with each other, they form polyurethane. This process is called “curing” and it is what gives polyurethane its strength and durability.

Polyurethane is said to be toxic because it is made from two toxic chemicals: isocyanates and polyols. However, cured polyurethane is not as toxic as uncured polyurethane. The most common health problems associated with polyurethane are skin irritation, allergic reactions, and asthma. If you are allergic to isocyanates, avoid products that contain them.

If you are allergic to isocyanates, avoid products that contain them.

Polyurethane products are safe to use if you don’t have an allergy to isocyanates. If you do have an allergy, avoid products that contain isocyanates.

What Is Polyurethane?

Polyurethane is a synthetic polymer made from a reaction between a polyol and a diisocyanate. It is known for its versatility, durability, and elasticity, making it a popular material for a wide range of products, including furniture, bedding, clothing, and footwear.

Polyurethane can be made into a variety of forms, including flexible foam, rigid foam, coatings, elastomers, and adhesives. It is also used in insulation, as a protective coating for wood and metal, and in medical applications, such as casting and padding.

Types Of Polyurethane

Is Polyurethane Toxic? Everything You Need To Know

There are two types of polyurethane:

1. Oil-Based Polyurethane

This is the most common type of polyurethane.

It is made by combining an isocyanate (a molecule with two nitrogen atoms) and a polyol (a molecule with more than one hydroxyl group).

The isocyanate and polyol are then mixed with catalysts and other additives to create the final product.

Oil-based polyurethane is usually clear or amber in color and is used for furniture, car parts, flooring, and other objects.

It is also more durable than water-based polyurethane.

2. Water-Based Polyurethane

This type of polyurethane is less common than oil-based polyurethane.

You make it by combining an isocyanate and a polyol but then adding water instead of oil.

Water-based polyurethane is usually white or off-white and is used for furniture, car parts, flooring, and other objects.

It is less durable than oil-based polyurethane.

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Is Polyurethane Toxic?

Now that we know a little bit about polyurethane, let’s explore the toxicity of this chemical compound.

The isocyanate in polyurethane is toxic and can cause respiratory problems if inhaled.

Exposure to isocyanates can also cause:

  • Asthma
  • Pneumonia
  • Bronchitis
  • Skin irritation
  • Eye irritation
  • Headaches

The polyol in polyurethane is not toxic, but it can cause skin irritation if it comes into contact with the skin.

Another compound that makes polyurethane toxic is the Volatile Organic Compound.

VOCs are a group of chemicals that can cause health problems if a person inhales them.

Some common symptoms of VOC exposure include:

  • Headaches
  • Nausea
  • Dizziness
  • Shortness of breath

Polyurethane is also flammable and can cause fires incase of improper handling.

Oil-Based Vs Water-Based: Which One Is More Toxic?

How To Spray Polyurethane, Polyurethane for Table Tops, Is polyurethane toxic

Polyurethane can be made from either oil-based or water-based components. The difference between the two is important when considering the toxicity of polyurethane.

Oil-based polyurethane typically contains higher levels of VOCs and is therefore considered to be more toxic than water-based polyurethane. Oil-based polyurethane releases VOCs into the air as it cures, which can have negative health effects if inhaled. Additionally, oil-based polyurethane is more flammable than water-based polyurethane and can release toxic fumes if burned.

Water-based polyurethane, on the other hand, contains lower levels of VOCs and is considered to be less toxic than oil-based polyurethane. It also has the added benefit of being less flammable and releasing fewer toxic fumes if burned.

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Conditions That Polyurethane Is Toxic In

Polyurethane can be toxic in certain conditions, such as when it is exposed to high heat or flame, or when it is broken down over time and releases VOCs into the air. Additionally, polyurethane products that are manufactured with toxic chemicals, such as formaldehyde, can be hazardous to human health.

Safety Tips

Some safety tips to avoid exposure to isocyanates and other toxic chemicals in polyurethane:

  1. Work in a well-ventilated area
  2. Wear a respirator
  3. Use gloves and protective clothing
  4. Avoid skin contact
  5. Wash hands after use

Incase of exposure to isocyanates, seek medical attention immediately.

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Storage And Disposal of Polyurethane

Proper storage and disposal of polyurethane products can reduce the risk of toxicity and environmental pollution.

  • Store polyurethane products in a cool, dry place, away from heat and flame sources.
  • Dispose of polyurethane products properly, following local regulations.
  • Avoid burning polyurethane products, as this can release toxic fumes into the air.


Is polyurethane food safe?

Polyurethane is not considered to be food safe. It should not come into direct contact with food, as it can leach chemicals into the food and potentially cause harm.

Is polyurethane leather toxic?

Polyurethane leather may contain toxic chemicals, such as formaldehyde, that can be harmful if inhaled or ingested. It is best to choose polyurethane leather products that are free of toxic chemicals.

What Should I Do If I Come into Contact with Polyurethane?

If you come into contact with polyurethane, rinse the area with soap and water. If it is in contact with your eyes, flush them with water for 15 minutes. Seek medical attention if symptoms persist.

Is Polyurethane Flammable?

Yes, polyurethane is flammable and can cause fires if you do not handle it properly.

Can I Store Polyurethane in My Garage?

No, you should not store polyurethane in your garage. It is important to keep it away from heat and flames, and store in a cool, dry place. 

Is Polyurethane Toxic When Dry?

No, polyurethane is not toxic when dry. The toxicity of polyurethane is eliminated by drying. However, it is important to avoid exposure to the vapors that come out during application. Another question people often ask is polyurethane food safe when dry. The FDA classifies polyurethane as food-safe.

Is Polyurethane Toxic to Pets?

No, polyurethane is not toxic to pets. However, it is important to keep it away from them as it can cause respiratory problems if inhaled. Remember, the toxicity of polyurethane is maximum when it is vaporized. This means caution must be taken when the polyurethane is yet to dry.

How long is polyurethane toxic?

Polyurethane is toxic when it vaporizes. Once it dries completely, polyurethane ceases to be toxic.


Polyurethane is a versatile and durable synthetic polymer used in a variety of products, from furniture and bedding to clothing and footwear. While its potential toxicity has raised concerns, it is important to understand the conditions under which polyurethane can be toxic and take appropriate measures to reduce exposure. Choosing water-based polyurethane products, avoiding exposure to high heat and flame, and properly storing and disposing of polyurethane products can all help reduce the risk of toxicity.

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