The returnable pots we use for our Refill products are professionally cleaned between each order to ensure that they are food safe and fit for reuse (see how here). These are checked again for cleanliness at the point of packing. This process does not, however, guarantee that they will be free from traces of the previous item they contained.
We keep the handling of our Refill and packaged products to a minimum to reduce the risk of cross-contamination. However, we do handle products covering all major allergens, along with our suppliers, and we pack orders in as few boxes as possible to save both plastic and carbon. This means we cannot guarantee that no cross-contamination will occur.
If you do suffer from major allergies, we would advise you not to order from Dizzie, as much as that saddens us to say so.