抄録
Bioaccumulation of di-2-ethylhexyl phtalate (DEHP) and di-n-butyl phtalate (DBP) by a wintering diving duck, Aythya fuligula, was studied by a conventional analysis modified to minimize contamination. The 0.061 μg · g-1 for DEHP and the 0.041 μg · g-1 for DBP were detected in a blank sample throughout whole procedure. Added DEHP and DBP were recovered at 105.2% and 106.3%, respectively. Trophic level of A. fuligula was examined using carbon and nitrogen stable isotope ratios. Nitrogen stable isotope ratios suggested that organic component of the liver of A. fuligula was changed with its food bivalve, Corbicula japonica, by 70 days after duck's arrival. Mean concentrations of DEHP and DBP on basis of fat in the livers of ducks and the flesh of C. japonica were 332μg · g-1 and 7.51μg · g-1 for DEHP, and 12.1μg · g-1 and 6.88μg · g-1 for DBP, respectively. Concentrations of DEHP in the livers of ducks increased towards the middle of December 1994, and decreased afterwards, suggesting that both bioaccumulation and decomposition of DEHP occurred in the liver of ducks. Increase of DEHP concentrations towards the middle of December 1994 was attributed to the backflow of saline water from urbanized area, because carbon isotope ratios and the concentrations of DEHP in the liver of ducks showed positive correlation.
