2 types of selenium here, one type is brewers yeast caps at 200 mcg -286% DV. The other is L-Selenomethione 200mcg - 280% DV.

DV - daily value

It could be anything you know... mercury, lead, cadmium, arsenic, antimony, the rug in the office, the mold in the basement.. milk... soy products.. the ink jet printer.. chemtrails.. flouride in the water...chlorine... pesticides...

I'd keep detoxing and eat the spirulina and whatever else gives you a lift. I get hammered for it a lot but my cilantro pesto recipe is a wonderful pick me upper. Use lots of parsley or basil with the cilantro for a great pick me up cleansing vitamin A packed punch. It's in the recipe section.