Among the cyanobacterial toxins, microcystins are the best-researched group and
probably occur most frequently in fresh waters. Many practical considerations for
the abatement of microcystins apply similarly to the other cyanotoxins (i.e. cylindrospermopsins,
saxitoxins, anatoxin-a and anatoxin-a(s)), with one key difference that
is relevant to the efficacy of their removal in drinking-water treatment: microcystins
are usually cell-bound, and substantial amounts are released to the surrounding water
only in situations of cell rupture (i.e. lysis), whereas the other cyanotoxins may occur
to a larger extent dissolved in water