Not Dishwasher Safe: Things You Should Never Put in the Machine
It’s safe and efficient to wash most of your dirty dishes in the dishwasher, but bear in mind that many kitchen tools and serving pieces should never be placed in the machine. If in doubt, keep it out!
For safety’s sake, certain plastics shouldn’t be washed in a dishwasher. A dishwasher’s heat can cause harmful chemicals such as phthalates and BPA to leach from plastics that contain them. If the manufacturer says the plastic is dishwasher-safe, place it on the top rack—away from the heating element. And don’t select cycles that use higher wash or dry temperatures, such as the “sanitize” cycle when washing plastic.
Everything on this list should be washed by hand, at all times:
Acrylic
Adhesive-joined pieces
Aluminum, including anodized aluminum
Antiques
Blown glass
Brass
Bronze
Cast iron
China with metallic decoration
Crystal
Disposable plastics not labeled “dishwasher-safe”
Flatware with bone, plastic, or wood inlays or handles
Gold-plated flatware
Iron
Knives
Many nonstick pots and pans (check manufacturer’s instructions first)
Milk glass
Pewter
Rubber tools
Tin
Wooden spoons
Here are a few more dishwasher “don’ts” to remember:
Don’t spill dishwasher detergent on flatware; it can cause dark spots.
Don’t use detergents containing chlorine, to avoid the release of chlorine fumes in the kitchen while running the dishwasher.
Don’t jam too many pieces into the silverware basket overcrowding can cause items to become scratched.
Don’t mix sterling or silver-plate and stainless-steel in the dishwasher, even when using the Rinse-Hold cycle. If the metals come in contact with each other, a reaction between the two metals can damage both finishes. (Since most knives, including sterling ones, have stainless-steel blades, keep them away from other silver pieces, too.)
make the switch to a biodegradable dishwasher detergent