India, Sept. 6 -- You may notice black spots on onions and wonder whether they are dirt or mould. Sometimes, even after you try to scrub them clean, the spots remain. So, what exactly are they? Are the onions safe to clean and use, or could they be dangerous to consume? In today's edition of Everyday Explained, we explore what causes these black spots and whether these onions should be eaten or discarded.ALSO READ: Everyday explained: Why are burgers almost always served with fries?

The US Department of Agriculture's Food Safety and Inspection Service (USDA) discussed mould on food.

Firstly, let us check what mould is. As per the USDA, moulds are microscopic fungi that live on plant or animal matter. So, the ones that you see on onions,...