Hello!
For those interested in the protein, vitamin Bs and other nutrient profiles of seaweeds, read the following book:
"Sea Vegetables -- Harvesting Guide and Cookbook" by Evelyn McConnaughey.
Published by Naturegraph Publishers Inc.
P.O. Box 1075
Happy Camp, California 96039
ISBN 0-87961-151-0
The author also talks about pollution uptake by sea vegetables.
some sea vegetables have significant quantities of vitamin B12
I recommend this book.
Mahesh