Yes, Algin is really used as protection against redistribution of mercury. This is because 90% of mercury excretes via the liver which dumps it into the colon, which is all too happy to reabsorb it. Algin travels in the colon (it is a non-digestible polysaccharide) and absorbs mercury very efficiently preventing reabsorption and encouraging elimination, which is—of course—very important because if you're detoxing or simply are mercury toxic, any reabsorbed mercury is redistributed which means more symptoms and more damage.