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Yes, you can put plastic in the dishwasher, but it depends on the type of plastic and how you load it.
Many plastics are labeled dishwasher-safe, meaning they can endure the heat and water pressure without melting or warping.
However, other plastics may be damaged or even leach chemicals if exposed to high dishwasher temperatures.
In this post, we’ll explore when and how you can safely wash plastic in the dishwasher, which plastics to avoid, and tips to protect your plasticware.
Let’s dive in!
Why You Can Put Some Plastic in the Dishwasher
If you’re asking, “Can plastic go in the dishwasher?” the short answer is yes—if it’s the right kind of plastic.
1. Dishwasher-Safe Plastics Are Designed for Heat
Many plastic items, like plates, cups, and food containers, are made from dishwasher-safe plastics such as polypropylene or certain types of polyethylene.
These plastics can handle the hot water and drying heat without warping or breaking down.
Look for a dishwasher-safe symbol on the bottom of your plasticware—it’s usually a little plate or cup with water droplets or a dishwasher icon.
2. Plastics Tested for Chemical Safety
Dishwasher-safe plastics are usually tested to ensure they won’t release harmful chemicals when heated.
This makes them safer for you and your family compared to plastics not intended for hot water cleaning.
3. Convenience and Hygiene
Putting plastic in the dishwasher can save you time and effort compared to hand washing.
Dishwashers use hot water and detergents that clean plasticware more thoroughly and sanitize them better.
This is especially useful for baby bottles, snack containers, and reusable plastic cups.
Which Plastic Items Should You Avoid Putting in the Dishwasher?
While the answer to “Can plastic go in the dishwasher?” is yes for some plastics, you should avoid putting certain types of plastic in the dishwasher to prevent damage and potential health risks.
1. Thin or Delicate Plastics
Thin plastics like disposable plastic cups, takeout containers, or lightweight lids often can’t withstand the dishwasher’s heat and pressure.
They may warp, melt, or crack during the wash cycle.
2. Non-Dishwasher-Safe Plastics
Some plastics are explicitly marked as “hand wash only” or lack any dishwasher-safe marking.
These plastics might discolor, degrade, or leach chemicals when exposed to dishwasher heat.
Common examples include some types of polystyrene (Styrofoam) or certain food storage containers.
3. Plastic Items with Adhesives or Decorations
Plastic items with stickers, decals, painted designs, or glued parts often don’t hold up well in the dishwasher.
The heat and water jets can peel or fade these decorations, ruining the look of your plasticware.
4. Older or Worn Plastic
Plastic items that are scratched, cracked, or worn down can be more susceptible to damage during dishwashing.
They might crack further or absorb dishwasher detergent chemicals, which is not safe.
Tips for Safely Washing Plastic in the Dishwasher
Even if your plasticware is dishwasher-safe, following some simple tips will help extend its life and keep your dishwasher working well.
1. Place Plastics on the Top Rack
The top rack of the dishwasher is usually farther from the heating element located at the bottom.
Placing plastics on the top rack reduces exposure to intense heat, preventing warping or melting.
2. Use a Gentle or Plastic Cycle
Many dishwashers have a cycle specifically designed for plastics or delicate items.
These shorter, cooler cycles protect lightweight plastics while ensuring cleanliness.
3. Avoid Overcrowding the Dishwasher
Crowding plastics tightly can block water spray and prevent thorough cleaning.
Make sure your plastic items have enough space so all surfaces are rinsed well.
4. Let Plastics Cool Before Removing
After the dishwasher finishes, plastic items can still be hot and soft.
Allow your plasticware to cool inside the dishwasher for a few minutes before handling to avoid deforming.
5. Check Manufacturer Recommendations
Always read the care instructions provided with your plastic items.
If the manufacturer says not to wash in the dishwasher, it’s best to follow that advice to protect your investment.
What Happens if You Put Non-Dishwasher-Safe Plastic in the Dishwasher?
You might be wondering what the consequences are if you put plastic that isn’t dishwasher-safe in there.
1. Warping and Melting
Heat is the biggest culprit.
Non-dishwasher-safe plastics can warp, melt, or lose their shape when exposed to hot water and drying heat.
2. Chemical Leaching
Some plastics release harmful chemicals when heated, especially if they’re made from lower-quality materials.
This can contaminate your dishes and potentially your food later on.
3. Dishwasher Damage
Melted plastic can stick to your dishwasher’s racks, heating element, or interior, causing damage or expensive repairs.
4. Poor Cleaning Results
Warped or cracked plasticware won’t wash properly and may end up with leftover food particles or detergent residue.
Are All Plastics Safe to Use in the Dishwasher?
No, not all plastics are dishwasher safe, and knowing which types to check for is important if you want to keep your items intact.
1. Look for Recycling Codes
Many plastics have recycling codes (numbers inside a triangle) that give clues about their dishwasher safety.
Plastics labeled 1 (PET), 2 (HDPE), 4 (LDPE), and 5 (PP) are often safer for dishwasher use.
Plastics carrying codes 3 (PVC), 6 (PS), and 7 (Other) can be less heat resistant and not recommended.
2. Consider BPA-Free Plastics
Bisphenol A (BPA) is a chemical once commonly used in plastics that can leach out under heat.
Many modern dishwasher-safe plastics are BPA-free, making them preferable for your kitchenware.
3. Plastic Thickness Matters
Thicker, solid plastic items generally tolerate the dishwasher better than thin or flimsy plastics.
Think reusable plastic plates or cups versus single-use items.
So, Can Plastic Go in the Dishwasher?
Yes, you can put plastic in the dishwasher, provided it is marked dishwasher safe and you use proper precautions.
Dishwasher-safe plastics handle the heat and water jets without damage and clean effectively.
Avoid washing thin, delicate, or non-dishwasher-safe plastics in the dishwasher because they may warp, melt, or release harmful chemicals.
Placing plastic on the top rack, using gentle cycles, and allowing them to cool before handling helps maintain their shape and safety.
Always check the manufacturer’s instructions and recycle codes to confirm if your plasticware can safely be washed in the dishwasher.
By following these tips, you can enjoy the convenience of washing plastic in your dishwasher without worries.
So go ahead—load up those dishwasher-safe plastic items and free yourself from extra hand washing!