Sponges, often used for hand-washing dishes, are another concern.
Warm, damp, and full of food particles, they provide ideal conditions for bacteria. A 2017 study identified 362 species of microbes in kitchen sponges, with densities reaching up to 54 billion per square centimetre. Yet another study found that only a small proportion of sponges contained harmful bacteria, and even then, the amounts were low.
In other words, sponges are packed with microbes, but most are harmless. To keep them hygienic, replace sponges weekly, or clean them in boiling water with disinfectant. Avoid leaving them in the sink, and squeeze out food and moisture after each use. Alternatively, brushes can be a cleaner option since they dry more quickly and are easier to wash.
Eco-friendly washing-up liquids are also available if you prefer to cut down on chemicals when cleaning by hand.
So, are dishwashers dangerous to your health? The evidence suggests not, as long as you use them properly and keep your machine clean.
