Memory foam mattresses commonly have a smell when first opened. This is due to the manufacturing process of the memory foam using polyurethane and other chemicals. The odour is called 'off-gassing'. This is NOT a fault with the product and the smell will go away after a few days. It is not toxic or harmful. We recommend leaving the mattress to air in a well-ventilated area, and use a fabric freshener like febreeze to help dissipate the smell. Other people recommend using vinegar water spray or baking soda to help relieve the smell.