I think Nodularia species also produces a hepatotoxin nodularin, which is similar in structure and activity to the cyanobacterial heptapeptide toxins, microcystins.
Hope you find the papers enclosed helpful.
1.Effect of salinity on growth and toxin production in cultures of the bloom-forming cyanobacterium Nodularia spumigena from Australian waters, SUSAN I. BLACKBURN, MALCOLM A. MCCAUSLAND, CHRISTOPHER J. S. BOLCH,STUART J. NEWMAN' AND GARY J. JONES,Phycologia (1996) Volume 35 (6), 511-522
2. Preliminary Characterization Of A Toxin Isolated From The Cyanobacterium Nodularia Spumigena,J. E. Eriksson, J . A. O. Meriluoto,Z H. P. Kujari, K. Österlund,K. Fagerlund And L. Hällboms,Toxicon ,1988