From what I'm told as long as they're API certified they're all the same.
https://www.api.org/products-and-ser...-exhaust-fluid
According to the following there are no other ingredients and there is no room for them in Blue DEF.
https://asset.productmarketingcloud....b-f8e7ef898b4b
https://asset.productmarketingcloud....2-0448658257d2