Thorvin used to sell Human Grade & Animal Grade in different colored 55 lb. bags. One Red & one Green, I believe. The label wasn't in English, so you had to go by the color.
I'd ordered a bag from a company and when I got it, it had been re-bagged and was actually only 50 lbs. -- so I returned it, because I wasn't sure what I was actually getting.
I think that to be sure one is getting People Grade, you'd have to get it in the original package, otherwise you don't really know what people are marketing.
Also, I think one is the Laminaria and the other is Ascophyllum.
Frustrating to have to do so much research just to find a good one!
Would appreciate anything you find out.