Can I put plastic in the dishwasher?

Plastic comes in all shapes and sizes and is found everywhere in our kitchens. There’s the tough, durable kind that lunchboxes and knife handles are made from; the soft pliable type, which you might use in a collapsible coffee cup; and the slim clear sort that’s often used for food containers or plastic bottles.

But despite how commonplace the material is, whether you can put plastic in the dishwasher will be dependent on the type of plastic item you have.

IS IT SAFE TO PUT PLASTIC IN THE DISHWASHER?

Whether or not it’s safe to put your plastic items in the dishwasher will depend on the type of plastic it is.

There are some plastic items that have been designed to withstand the heat and cleaning action of detergents in a dishwasher cycle - these products will generally be labelled as ‘dishwasher safe’. But, if you’re still unsure, here are some common types of plastic, and how suitable they are for dishwashing.

REUSABLE PLASTIC CONTAINERS

If a plastic bottle or container has been marked as reusable, it should be safe to go in your dishwasher – under certain conditions. When washing these kinds of products, always put them on the top rack (far away from the heating component) and avoid using deep clean or sanitising cycles¹.

TABLEWARE AND CUTLERY

Outdoor plates and cutlery, babies’ bottles, plastic chopping boards and acrylic glasses should all be made of dishwasher safe plastic, but again, certain precautions should be taken when washing. No matter how robust the plastic may be, high temperatures are likely to impact it.

DISPOSABLE PLASTICS

Disposable plastics (such as food containers and water bottles) are not dishwasher safe. Not only are they made from a type of plastic that is not designed to withstand heat, meaning they will warp and become unusable, they also often feature an ingredient (BPA, or BPA alternatives) that could be harmful to your health.

CAN BPA-FREE PLASTIC GO IN THE DISHWASHER?

If a plastic is labelled as BPA-free it means it does not include the chemical ingredient bisphenol A (BPA), a compound that hardens plastic. Unfortunately, BPA has been found to affect the food and beverages that the container holds, and evidence suggests that it can be damaging to our health when consumed.

The heat from your dishwasher could cause BPA to leach from the plastic containing it, so plastic with BPA should NOT go in the dishwasher².

Products labelled BPA-free should still be considered before using in the dishwasher, however. Some companies claim their products are BPA free, yet use similar compounds (such as BPS, BPF and BPAF) that may have similar health effects to BPA.3 As such, it’s best to check if the product is truly BPA free before putting it in the dishwasher.