206
Crustacea and Molluscs
were subsequently removed from the charcoal column with benzene. Recoveries from
oyster samples were between 68 % (PCBs) and 102 % (heptachlorepoxide). Limits of
detection were between 0.041lg kg- I (lindane) and 6.5 Ilg kg- I (PCBs).
Tanabe et al. [599] used mussels as bioindicators of PCB pollution. When uncontaminated green lipped mussels were transplanted in severely contaminated Hong Kong
Bay waters, total PCB concentrations increased from llllg kg- I wet weight to
560 IlS kg- I wet weiqht in 17 days. When remaining mussels were returned to clean
waters after 17 days, total PCB concentrations decreased from 630 IlS kg- I wet weight
to 12 IlS kg- I wet weight within 32 days. Lower chlorinated PCBs (isomers and congeners containing 2-4 chlorine atoms) were taken up and depurated more rapidly than
the more lipophilic higher chlorinated PCBs (hexa-, hepta- and octachlorobiphenyls).
It was suggested that time-bulking (combining samples collected at frequent intervals
from a single location) in PCB monitoring studies involving bivalves would provide a
more accurate picture of average contamination conditions.
Ya Ma and Bayne [760] discriminated polychlorobiphenyls in clam tissue using
electron capture negative ion chemical ionization mass spectrometry.
8.2.6
Polychlorinated Terphenyls
The presence of polychlorinated terphenyls has been reported in oyster tissue. To
determine polychlorinated terphenyl in oyster, a hexane extract [600] was cleaned on
alumina or Florisil, and the analysis performed using a combination of a mass
spectrometer and a gas chromatograph used in the mass fragmentography mode. Two
m/ e values were selected (m/ e = 436 and m/ e = 470). Approximately 0.151lg kg- I
polychlorinated terphenyl and 0.2 Ilg kg-I PCB were found in oyster tissue.
8.2.7
Polychlorinated Dibenzo-p-dioxins and Dibenzofurans
Taguchi et al. [466] used high resolution mass spectrometry to determine these
substances in crustacea tissue.
Buser [741] determined polychloro-benzothrophenes, the sulphur analogues of
polychloro-dibenzofurans in crab, lobster and worm using various gas chromatographic-mass spectrometric techniques.
8.2.8
Phthalate Esters
The gas chromatographic procedure [409] described under phthalate esters in
Sect. 7.3.3 for the analysis of fish is also applicable to the determination of these
substances in shrimps and crab. Between 3 and 20 IlS kg- I of diethyl hexyl phthalate
was found in crab taken in the Gulf of Mexico, while dimethyl, diethyl and dibutyl
phthalates occurred at concentrations less than the detection limit of the method
(IllS kg-I).
Crustacea and Molluscs
were subsequently removed from the charcoal column with benzene. Recoveries from
oyster samples were between 68 % (PCBs) and 102 % (heptachlorepoxide). Limits of
detection were between 0.041lg kg- I (lindane) and 6.5 Ilg kg- I (PCBs).
Tanabe et al. [599] used mussels as bioindicators of PCB pollution. When uncontaminated green lipped mussels were transplanted in severely contaminated Hong Kong
Bay waters, total PCB concentrations increased from llllg kg- I wet weight to
560 IlS kg- I wet weiqht in 17 days. When remaining mussels were returned to clean
waters after 17 days, total PCB concentrations decreased from 630 IlS kg- I wet weight
to 12 IlS kg- I wet weight within 32 days. Lower chlorinated PCBs (isomers and congeners containing 2-4 chlorine atoms) were taken up and depurated more rapidly than
the more lipophilic higher chlorinated PCBs (hexa-, hepta- and octachlorobiphenyls).
It was suggested that time-bulking (combining samples collected at frequent intervals
from a single location) in PCB monitoring studies involving bivalves would provide a
more accurate picture of average contamination conditions.
Ya Ma and Bayne [760] discriminated polychlorobiphenyls in clam tissue using
electron capture negative ion chemical ionization mass spectrometry.
8.2.6
Polychlorinated Terphenyls
The presence of polychlorinated terphenyls has been reported in oyster tissue. To
determine polychlorinated terphenyl in oyster, a hexane extract [600] was cleaned on
alumina or Florisil, and the analysis performed using a combination of a mass
spectrometer and a gas chromatograph used in the mass fragmentography mode. Two
m/ e values were selected (m/ e = 436 and m/ e = 470). Approximately 0.151lg kg- I
polychlorinated terphenyl and 0.2 Ilg kg-I PCB were found in oyster tissue.
8.2.7
Polychlorinated Dibenzo-p-dioxins and Dibenzofurans
Taguchi et al. [466] used high resolution mass spectrometry to determine these
substances in crustacea tissue.
Buser [741] determined polychloro-benzothrophenes, the sulphur analogues of
polychloro-dibenzofurans in crab, lobster and worm using various gas chromatographic-mass spectrometric techniques.
8.2.8
Phthalate Esters
The gas chromatographic procedure [409] described under phthalate esters in
Sect. 7.3.3 for the analysis of fish is also applicable to the determination of these
substances in shrimps and crab. Between 3 and 20 IlS kg- I of diethyl hexyl phthalate
was found in crab taken in the Gulf of Mexico, while dimethyl, diethyl and dibutyl
phthalates occurred at concentrations less than the detection limit of the method
(IllS kg-I).