UPTAKE OF A NON-CALORIFIC, EDIBLE SUCROSE POLYESTER OIL AND OLIVE OILBY MARINE MUSSELS AND THEIR INFLUENCE ON UPTAKE AND EFFECTS OF ANTHRACENE

The fate and potential toxicological effects of a new non-calorific sy nthetic fat, sucrose polyester (SPE), proposed as a fat substitute in human food, was evaluated in aquatic systems. The aims of this investi gation were to assess the persistence of SPE in aquatic systems and to determine: whether SPE is taken up by digestive gland cells of the ma rine mussel; if it is acculmulated; if it induces pathology; and if it enhances the uptake of lipophilic xenobiotics. SPE oil was found to b e only moderately degraded compared to the complete conversion of oliv e oil, thus indicating that estuarine and marine biota could be expose d via sewage effluent. An in vitro study exposed isolated digestive ce lls from the marine mussel to fluorescent (Nile Red), olive oil (diges tible) and SPE oil (non-digestible) at concentrations of 10, 100 and 1 000 ppm for 4 hours. In all cases, there was evidence of endocytic upt ake of the oils, in a concentration-related manner. There was no evide nce of toxicity by either oil or Nile Red based on the lysosomal neutr al red retention assay. Mussels exposed for 3 days to one of various t reatments: (1) control; (2) anthracene 200 ppb; (3) olive oil IO ppm; (4) olive oil 10 ppm+anthracene 200 ppb; (5) SPE oil IO ppm; (6) SPE o il 10 ppm+anthracene 200 ppb, showed no overt evidence of tissue patho logy. However, there were marked subcellular effects in digestive cell s with anthracene, including significant decreases in lysosomal membra ne integrity. Combined treatment with the SPE oil and anthracene resul ted in a doubling in anthracene uptake and significantly greater reduc tion in lysosomal membrane integrity than with anthracene alone. The o verall conclusions are that the SPE oil is taken up by cells of the di gestive system and the implication of this in the longer term is that lysosomal lipid storage disease (lipidosis) could be induced. The SPE oil also facilitates the uptake of a representative lipophilic xenobio tic pollutant (anthracene), thus enhancing toxicity and cell damage. C rown copyright (C) 1997 Published by Elsevier Science B.V.