Here is something I found on zeolite from the same website someone recommended on this forum, interesting reading:

Zeolite clay is natural, inert, non-toxic, environmentally friendly substances that is known to remove toxic metals from waste water, land, septic systems and the air. Zeolites can adsorb huge amounts of materials such as ions or gas molecules. Zeolite clay has an unusual crystalline structure and is tetrahedral in shape, similar to a honeycomb appearance. The channels and holes in the sponge-like structure of zeolite have a uniform shape and size. It is this unique crystalline structure that gives zeolite clay such unusual capabilities of filtering, mineralizing, and absorbing toxic wastes. In one gram of zeolite, the channels in its structure provide up to several hundred square meters of surface area on which adsorption and chemical reactions can take place. Its unique structure acts like sieves, or ?shape-selective catalyst,? catching only molecules small enough to fit into the cavities, while excluding larger molecules.


There are around 50 different kinds of natural zeolites and about 150 synthetic versions with varying physical and chemical properties. Natural zeolites were discovered as major constituents of numerous volcanic tuffs in saline-like deposits. Zeolite contains the minerals potassium, calcium, silicon, hydrogen, oxygen, aluminum and sodium. Zeolite clay has been beneficial in remineralizing and re-establishing pollution control in the soil and for use in hydroponic plant growth. The high purity of the natural deposits has aroused considerable commercial interest in the United States and abroad. The name ?zeolite? literally means ?boiling stones.?

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Zeolite clay has been a medium for air filters, water filters, and odor control. It is environmentally friendly for waste dump sites and has been used as a filter medium for the removal of radioactive wastes and for the removal of heavy chemical toxins and heavy metals such as iron, zinc, cadmium, lead, and copper, deemed hazardous by the government, from individuals as well as from mining and water waste sites. Zeolite clay has been used successfully for the extraction of radionuclides from human beings and animals.

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The natural zeolites can absorb up to 30% of their dry weight of gases, such as nitrogen or ammonia. Toxic gases, chemicals, mold, mildew, formaldehyde, and other toxins are drawn by the natural negative electrical charge into the crystal micro pores of the clay. The odors and gases are removed, not merely covered up. Research is now being done by several companies for its use as an absorbent of excess moisture, molds, and fungi. ?Pouches? of zeolite clay are now available for, not only odor control, but the elimination of toxic gases and chemicals, smoke, and radioactive gases. These ?pouches? are placed in a room, and act like a magnetic sponge.

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The British Nuclear Fuels (BNF) uses this specific type of zeolite to remove radioactive strontium and cesium and, therefore, reduces the radioactivity of liquid waste discharged into the Irish Sea . The Hanford , Washington nuclear weapons facility, uses this same kind of zeolite to prevent contamination. This type of zeolite also had a role in the cleanup after the atomic energy plant accident at Three Mile Island . A Swedish study showed another kind of zeolite could decontaminate live animals and meat affected by the Chernobyl disaster.