ABSTRACT
The microscopic planktonic algae are a critical food or different filter-feeding planktonic bivalves, such as shellfish (oyster, mussels, scallops, and clams), also for larvae of commercially important crustaceans and finfish. Moreover, among the 5000 existing marine algal species, approximately sometimes a significant number of these creatures can occur in such a high number (blooming) that they obviously discolor the surface of the lagoons, coastal areas, and the contaminated shore of seas. The term “Bloom” usually is used to indicate massive growth of any of these organisms, which they are may vary in color from the commonly cited red so they called “Red tides” for different shades of blue, brown, green, and yellow depending on the type of algae, their depth, and concentration. The conditions of the algal bloom are not fully elucidated yet but the phenomenon probably is influenced by hydrographic circumstances and climate change. Sometimes, the massive growths appear during changes of weather conditions but an important contributing cause may be variations in upwelling’s temperature, transparency, turbulence or salinity of the water, concentrations dissolved nutrients, illumination of the surface, and the wind. But the importance of this case is there are many species of planktonic algae can produce toxins, such as Paralytic shellfish toxins, namely Diarrheic shellfish toxins, Amnesic shellfish toxins, Neurotoxin shellfish toxins, and Azaspiracid shellfish toxins. These toxins are called marine biotoxins and there were other different types of toxins in the freshwater ecosystem; however, marine biotoxins can impact the health of human and 418his food resources in seas. Actually, this phenomenon needs efforts to face the real challenge of Marine (biotoxins). Different phytoplankton species can produce different types of toxins or else different species can produce one type of toxin, for example, toxic plankton as a species Dinophysis sacculus and as a genus Gyrodinium, protoperidinium and Prorocentrum. All these toxins are producible from phytoplankton mostly in warm time especially in spring, therefore, many countries depend on early mentoring to keep people safe especially at summer when they spend time on the beaches, but unfortunately knowledge about phytoplankton is day by day increasing and it is found that the range of its spreading in the world via trade ships as one of probable factor which can clarify toxic phytoplankton as exotic species may be in noneffected shores or aquatic basin and lagoons in coastal areas. Several projects on aquaculture and bivalves’ cultures have a threat of toxicity by marine toxins when they import mothers of bivalves and larvae of wild fish to develop them and produce seafood, actually by valves are accused to transfer toxic phytoplankton from effected basin or bivalves farm to noneffected one. The answer is why these creatures are toxic? Or is it not nontoxic before activities, here we can say we need rearrangement or reducing the quantity of pollutants inputs which were and are increasing day after day to at least to control managing real solutions of this global phenomenon, because it is one of the bioresources at this planet.
