People will answer.
Pine sucks, so does any other softwood (aromatic). They are toxic to some degree or another, not to mention the sap is messy. As far as I know, apple is fine. Sealing the wood is a good idea for cleaning and to help keep out pathogens. You can use an exterior urethane or if you wanted to go a full job, an epoxy... epoxy probably isn't necessary unless its a swampy environment.