Dugesia dorotocephala

ORGANIC MERCURY Freshwater Planarians Flatworm, Dugesia dorotocephala Adult LCO (10 d) 200.0 12... 

Best, J.B., M. Morita, J. Ragin, and J. Best, Jr. 1981. Acute toxic responses of the freshwater planarian, Dugesia dorotocephala, to methylmercury. Bull. Environ. Contam. Toxicol. 27 49-54. 

Levy, R. and T.W. Miller, Jr. 1978. Tolerance of the planarian Dugesia dorotocephala to high concentrations of pesticides and growth regulators. Entomophaga 23 31-34. 

L.R. Johnson, R. Davenport, H. Balbach, D.J. Schaeffer (1994). Comparative toxicity of trinitrotoluene and aminodinitrotoluenes to Daphnia magna, Dugesia dorotocephala, and sheep erythrocytes. EcotoxicoL Environ. Saf, 27, 34-49. 

Coexposure of D. magna to nitroaromatic compounds (TNT, 2-A-4,6-DNT, or 4-A-2,6-DNT) and near-ultraviolet radiation (near-UV 312-354 nm), after an initial 12-h exposure to the chemicals in the dark, promoted a significant toxicity increase (four- to fivefold) of the three chemicals [64], Similar experiments with the planarian Dugesia dorotocephala only exhibited increased toxicity of 2-A-4,6-DNT (tenfold) with near-UV coexposure, but not of the other two chemicals [64], In the absence of organisms, TNT was phototransformed, that is, transformed into breakdown products, by near-UV exposure (from 336 to 400 nm), whereas 2-A-4,6-DNT and 4-A-2,6-DNT remained stable. Therefore, photoactivation would be the likely cause of the enhanced effect of the ADNTs, whereas phototransformation products may have contributed to the increase in toxicity exhibited by simultaneous exposure of the organisms to TNT and near-UV. Alternatively, it is possible that the phototransformation products were photoactivated. Coexposure to near-UV for 30 min, but not for 15 min, also enhanced toxicity of these chemicals to the bacterium V. fisc fieri (Microtox test) [38], It is not clear if this is a result of the formation of a new, more toxic TNT metabolite in 30 min, but not 15 min, or if 30 min would be the minimum time for a sufficient amount of the chemicals to be bioaccumulated to enable the occurrence of the photoactivation process within the cells. 

Meyer, F., Meyer, H. and Bueding, E. (1970) Lipid metabolism in the parasitic and free-living flatworms Schistosoma mansoni and Dugesia dorotocephala. Biochim. Biophys. Acta 210 257-266. 

In the planarian Dugesia dorotocephala, asexual fission was suppressed at 0.03-0.1 xg organomercury/L at 80.0-100.0 xg methyl-mercury/L, behavior was modified and regeneration retarded. 

According to Perkins and Fried 102 free sterols and fatty acids may have pheromonal activity in planaria such as Dugesia tigrina and D. dorotocephala. 

Perkins, C., and B. Fried Intraspecific Pairing of Planaria, Dugesia tigrina and D. dorotocephala (Platyhelminths Turbellaria), and Observations on Lipophilic Excretory-Secretory Worm Products. J. Chem. Ecol. 8, 901-909 (1982). 

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