DishwashersGuide
Is It Safe to Wash Plastic in the Dishwasher?
Most plastics marked dishwasher-safe are safe on the top rack. Heat and harsh detergents can warp or degrade other plastics. Check the resin code and symbol first. Avoid washing thin, single-use plastics. Use low heat and air dry to protect items.
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Check for the dishwasher-safe symbol or resin code before loading plastic.
- Place plastic on the top rack and avoid the heated dry cycle.
- Avoid thin, single-use plastics and those with codes 3, 6, or 7.
- Use a gentle cycle with mild detergent to prevent warping and chemical release.
What Makes Plastic Dishwasher Safe?
Dishwasher-safe plastics are made to withstand heat and moisture. They typically have a resin identification code of 1, 2, 4, or 5. Polypropylene (5) and high-density polyethylene (2) resist heat well. Polycarbonate (7) may contain BPA and is not recommended. Look for a symbol of a cup and plate with water droplets. This symbol means the item passed a dishwasher safety test.
Which Plastics Should You Avoid in the Dishwasher?
Avoid plastics with codes 3 (PVC), 6 (polystyrene), and 7 (other). These can warp or release chemicals at high temperatures. Thin, flimsy plastics like yogurt cups and takeout containers are not safe. They may melt or deform. Also avoid plastic items with glued parts or decorative prints. The heat can cause delamination or fading.
How to Wash Plastic in the Dishwasher Safely
Place plastic items on the top rack, away from the heating element. Use a gentle cycle with lower water temperature. Skip the heated dry cycle; open the door to air dry instead. Use a mild detergent without chlorine bleach. If you see warping or a chemical smell, stop washing that item in the dishwasher.
Dishwasher Safe vs. Top Rack Only: What's the Difference?
Some plastics are labeled 'top rack only' because they cannot withstand the lower rack's heat. The bottom rack is closer to the heating element and gets hotter. Top-rack-only items may include thin containers, lids, and baby bottles. Always follow the label to prevent damage. If there is no label, treat it as not dishwasher safe.
What About Baby Bottles and Food Storage Containers?
Baby bottles made of polypropylene (5) are generally dishwasher safe. Place them on the top rack and use a gentle cycle. Food storage containers with lids often have a dishwasher-safe symbol. Check the base and lid separately; lids may be less heat-resistant. To extend the life of any plastic, hand washing is always gentler.
Common questions
Can plastic melt in the dishwasher?
Yes, plastics not rated for high heat can melt or warp. The heating element and hot water can reach temperatures above 140°F. Thin plastics like takeout containers are especially vulnerable. Always check for a dishwasher-safe symbol before loading.
Is it safe to wash plastic baby bottles in the dishwasher?
Most modern baby bottles are made of polypropylene (5) and are dishwasher safe. Place them on the top rack and use a gentle cycle. Avoid the heated dry cycle to prevent warping. Check the bottle's label for specific instructions.
What does the dishwasher safe symbol look like?
It usually shows a cup and plate with water droplets or spray above them. Sometimes it includes the words 'dishwasher safe.' The symbol may be on the bottom of the item. If you don't see it, assume it's not safe.
Can I wash plastic Tupperware in the dishwasher?
Tupperware brand containers are generally dishwasher safe, but check the label. Many are top-rack only. The lids may be less heat-resistant than the bases. To prevent warping, use a low-heat cycle and air dry.
Is it safe to wash plastic water bottles in the dishwasher?
Reusable water bottles made of polypropylene (5) or Tritan (a BPA-free plastic) are often dishwasher safe. Check the bottom for a symbol. Insulated bottles may have a vacuum seal that can be damaged by heat. Hand washing is recommended for those.
Does the dishwasher cause plastic to release harmful chemicals?
Heating plastics can increase the release of chemicals like BPA, but only if the plastic contains BPA. Many plastics are now BPA-free. Avoid polycarbonate (7) plastics in the dishwasher. Use mild detergents and lower heat to minimize any risk.
What happens if I accidentally wash non-dishwasher-safe plastic?
The item may warp, melt, or become misshapen. It could also release a chemical smell. In some cases, it might ruin other dishes. If you notice damage, remove the item immediately. Check your dishwasher's filter for any plastic residue.
Is it better to hand wash plastic containers?
Hand washing is gentler and can extend the life of plastic items. It avoids high heat and harsh detergents. However, dishwashers are more convenient and can sanitize better. For plastics that are dishwasher safe, both methods are fine. For delicate items, hand washing is safer.
