Mussels toxicity studies

ProrocerUrum lima also produces OA and its derivatives (44,45) and is distributed in mussel farming areas (Fraga, Lee and Yasumoto, unpublished data). Contribution of P. lima to mussel toxicity awaits further studies. 

In response to the concern expressed by the shellfish farmers operating in the Ebro River delta about the potential positive role of pesticides on the oyster and mussel mortalities observed in the area, our group, commissioned by and with the collaboration of the Catalan Water Agency (ACA), carried out a comprehensive study in which chemical and toxicity data were combined to assess potential toxic presures present in the delta. To this end, a combined approach scheme integrating the measurement of various general physicochemical parameters in water, quantitative chemical analysis of pesticides in water and biota, and ecotoxicity assays in water was applied to a series of samples collected at springtime (between mid-April and mid-June 2008) from six selected sites of the delta the two (northern and southern)... 

Hietanen, B., I. Sunila, and R. Kristoffersson. 1988. Toxic effects of zinc on the common mussel Mytilus edulis L. (bivalvia) in brackish water. I. Physiological and histopathological studies. Annales Zool. Fennici 25 341-347. 

Disposition of Toxic Substances in Mussels (Mytilus califorianus) Preliminary Metabolic and Histologic Studies... 

Quantitative estimation of ventilation by indirect methods in mussels requires four assumptions (16) a) reduction of concentration results from uptake, b) constant ventilation (pumping) rate, c) uptake of a constant percentage of concentration (first order process), d) homogeneity of the test solution at all times. Our transport studies have utilized antipy-rine (22, 23) a water soluble, stable chemical of low acute toxicity to mussels. It is readily dissolved in ocean water or Instant Ocean and is neither adsorbed nor volatilized from the 300 ml test system. Mussels pump throughout the 4 hour test period and this action is apparently sufficient to insure homogeneity of the solution. Inspection of early uptake and elimination curves (antipyrine concentration as a function of time) prompted use of Coughlan s equation (16) for water transport. 

Despite this progress, the evidence linking cysts to shellfish toxicity remains circumstantial and care should be exercised before attributing toxin increases to this mechanism. The major problem is that it has yet to be demonstrated that shellfish can remove toxin from cysts. The feeding studies mentioned earlier (which do not yet include scallops 35) indicate that many viable G. tamarensis cysts can be isolated from the fecal pellets of mussels and soft-shelled clams fed cyst suspensions. There is certainly some cyst mortality as well (Figure 5), but whether this is also associated with toxin retention by the shellfish has yet to be demonstrated. It is reasonable to expect that the assimilation of toxin from cysts will not be a highly efficient process. 

This chapter provides a comprehensive review of the studies on persistent toxic substances (PTS) in the Philippines environment. Available information on PTS in the Philippines was compiled on the basis of investigations conducted within the framework of multilateral cooperative research between Japan and the Philippines through the Core University Program of the Japan Society for the Promotion of Science (JSPS) and the Asia-Pacific Mussel Watch Program. Results from other laboratories were likewise included to derive greater insights into the... 

Biological indicator species such as fresh water sponges, clams, mussels, insect larvae that sorb water-borne pollutants are difficult to assess over time periods of years. The lanthanides may be used as indicator species utilizing the adventitious roots of stream-side trees [204-206]. The ability of tree roots to sorb both chelated and non-chelated lanthanides from water indicate that aquatic roots accumulate, concentrate and retain lanthanides to such an extent that the roots can be used as indicators of aquatic pollution, and that lanthanides can be studied as analogues of toxic elements and compounds. 

The consumption of shellfish (scallops and mussels) harvested during late spring to early summer fiom the northeastern region of Japan quite often results in what is commonly known as diarrhetic shellfish poisoning. An initial chemical investigation of the toxic mussels resulted in the identification (86) of okadaic acid [108], dinophysistoxin 1 (DTXj) [109] and two toxins of unknown structures. In a later study (87), chemical structures of three new polyether toxins, dinophysistoxin- 3 (DTX3)[110], pectenotoxin-1 [111 ] and pectenotoxin-2 [112] were reported. 

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