You Can Put Plastic In The Dishwasher, But Not This Kind - Tasting Table

"Plastics are fine for the most part, but thin plastics, acrylic, and melamine are three things you shouldn't put in the dishwasher. Soft or thin plastics like takeout containers or plastic water bottles are often designed to be single use, and their lightweight construction means they can melt easily. Even of more concern is that they can release harmful chemicals when heated."

"Acrylic dishes won't melt as easily as thin plastics do, but they can still warp. The combination of heat and water pressure can also cause scratches and cracks in the surface which can then harbor bacteria. You might find that the heat also causes the acrylic to turn cloudy. Melamine dishes, on the other hand, are less black and white. Some melamine dinnerware will be labeled dishwasher safe, but there is often a temperature limit."

Thin plastics, acrylic, and melamine require caution around dishwashers because heat and water pressure can damage them or cause chemical release. Thin or single‑use plastics can melt and may emit harmful chemicals when heated. Acrylic can warp, scratch, crack, harbor bacteria, and turn cloudy under dishwasher conditions. Melamine may be labeled dishwasher safe but often has temperature limits and can crack or fade over time. Items without clear labeling should be assumed not dishwasher safe. Hand washing with mild detergent and avoiding very hot water helps protect sensitive plastics and reduce risk of BPA release.

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