The present invention relates to compositions and methods for the removal
of toxic metals or radionuclides from source materials. Toxic metals may
be removed from source materials using a clay, such as attapulgite or
highly cationic bentonite, and chitin or chitosan. Toxic metals may also
be removed using volcanic ash alone or in combination with chitin or
chitosan. Radionuclides may be removed using volcanic ash alone or in
combination with chitin or chitosan.