It is well known that alginates from kelp and rockweed can bind heavy metals. It is also a scientific fact that some seaweed in your food protects your body against absorbing such heavy metals as we are increasingly taking in with our food. You can see if your vegetables are fresh, but you cannot see if they have grown so close to a road with heavy traffic, that they are contaminated with lead from car exhausts. You cannot see if they have been fertilized with sludge and contaminated with cadmium or mercury.
What we know is that today everybody gets quite small amounts of heavy metals. Hopefully the quantities are below toxic levels. Certainly all healthy, strong and thriving people do not take in more than their kidneys can excrete. When you feel out of form, limp, powerless, ask your doctor, you might be ill. If you are not, try Rörö Seaweed cure! You might have too little of som trace elements or too much of heavy metals.