Ultra Tested Tested For Than More Than 950 Contaminants Heavy Metals- Bacteria- Yeast- Mold- Pesticides & More Casein & Gluten Free Hypoallergenic Dietary Supplement Kirkman offers selenium in 100 mcg hypoallergenic capsules formulated for individuals with special requirements and sensitivities Selenium is an essential trace mineral that functions primarily as an antioxidant in the body. It works synergistically with vitamin E in reducing free radical damage to cell membranes. Selenium is also associated with supporting a healthy immune system. Selenium is antagonistic to heavy metals including lead, mercury, aluminum and cadmium and may offer protection from environmental traces of these contaminants. Kirkman's selenium capsules utilize L-Selenomethionine as the selenium source. This is a biologically active form, which was very effectively absorbed in clinical studies conducted by the Nutrition 21 Corporation.