there's no common practice or recommendation for storing bed sheets in the freezer. The freezer is designed to store food and maintain low temperatures to prevent bacterial growth and food spoilage. While some fabrics might survive being stored in the freezer for a short period, it's not an appropriate or typical way to handle bed sheets.
If you're concerned about dust mites or allergens in your bed sheets, the best practice is to wash them regularly using the manufacturer's recommended care instructions. Washing with hot water and drying them at high temperatures can help eliminate dust mites and allergens effectively.
Remember, always follow the care instructions provided by the manufacturer to ensure your bed sheets remain clean, comfortable, and durable. If you have specific concerns or issues with your bed sheets, consulting with a bedding specialist or healthcare professional can be beneficial.