Platyhelminthes, Nematoda, Nemertini and Minor Phyla

Nothing, or virtually nothing, is known about the metabolism of organic xeno-biotics in marine organisms of these phyla, or the various smaller phyla such as Brachiopoda, Gastrotichia, Rotifera etc. The limited information available is mainly for freshwater or parasitic species of the phyla and, therefore, can only be taken as an indication of the situation in marine species. 

Organochlorine compounds are taken up from the water column by freshwater planarians (free-living platyhelminths). Aldrin was taken up by Dugensia sp. (Khan 

269 nmol g ) (Kouyoumijan and Villeneuve 1979). Aliphatic and aromatic hydrocarbons were taken up from oil-contaminated marine sediments by the sipunculid Phascolosoma agassizii (Roesijadi et al. 1977). Animals exposed in the field to Prudhoe Bay crude oil (443 to 887 pg total hydrocarbons g sediment) accumulated, after 40 days, 0.73 to 1.90 fig g wet weight Cig-Cgg aliphatics (= 2.6 to 6.7 nmol g av. mol. wt. of282 used) and 0.16 to 0.83 fig g naphthalenes (=1.0 to 5.5 nmol g ). 

expansa was cytosolic and conjugated CDNB but not bromobenzene or chlorobenzene (Douch and Buchanan 1978). Similarly, glutathione-S-transferase activity in H. contortus was observed only with CDNB as substrate and not with DCNB or l,2-epoxy-3-(p-nitrophenoxy)propane (Kawalek et al. 1984). Neither M. expansa not A. suum produced glucuronides with 4-nitrophenol, 2-aminophenol or 4-methylumbelliferone (Douch and Blair 1975), or possessed measurable DDT-dehydrochlorinase activity (Douch and Buchanan 1978). Various specific (cholinesterase) and non-specific esterases have been detected in trematodes, e.g. using a-naphthyl acetate as substrate, in A laria marcianae (Dickinson and Johnson 1978) and Schistosoma mansoni and Schistosoma haematobium (Coles 1970). 

MFO activity was not detected in the sipunculid worms, P. agassizzii (Lee 1981) and Sipunculus spinifer (Batel et al. 1983). 

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