In the mid-19th century shellfish were a major dietary source of protein for the citizens of the United States on both the East and West Coasts. This is no longer the case, largely because of our inability to guarantee that those who wish to eat shellfish can do so safely. Paralytic shellfish poison (PSP) is known to have been the cause of death of at least 32 people in California alone, from 1927 to 1980. During this period some 508 cases of non-fatal PSP were reported in the State. The inability at present to detoxify Shellfish is the major barrier to the development of shellfish mariculture in the U.S. and elsewhere in the world. Neushul Mariculture Incorporated (NMI), has cultured toxic dinoflagellates and measured the kinds of and amounts of toxin in them, using a home-made post-reaction column attached to a high-performance liquid-chromatograph (HPLC). The toxic algal cells were then fed to mussles in varying amounts at varying rates and toxin accumulation was measured, by HPLC and mouse and fly bioassays. Finally the process of natural detoxification was followed over time. This sets the stage for more detailed studies of toxin accumulation and detoxification, the principal goal being to make U.S. shellfish once again safe to eat.