Subject(s)
Bivalvia/metabolism , Cadmium/metabolism , Edetic Acid/metabolism , Zinc/metabolism , Absorption , AnimalsABSTRACT
The concentration of PCB, as Aroclor 1254, accumulated from sandy sediment by Nereis virens is directly related to PCB concentration in sediment and to exposure time, and is inversely related to worm size. There was no indication of equilibrium concentrations being attained during 32 days' exposure. Concentration factors at 32 days ranged from 10.8 for 0.6-g worms to 3.8 for 4.7-g worms. There was no obvious excretion of PCB by N. virens during 26 days' post exposure. Accumulation of PCB by Crangon septemspinosa is directly related to PCB concentration in sediment and inversely related to animal size. Concentration factors at 32 days ranged from 3.5 for 0.1-g shrimp to 1.9 for 2.9-g shrimp. Field collected N. virens ranging in weight from 1.3 to 20.0 g were analyzed for PCB, sigma DDT and dieldrin. Smaller worms had accumulated more per unit weight of each compound than larger worms.
Subject(s)
Decapoda/metabolism , Polychaeta/metabolism , Polychlorinated Biphenyls/metabolism , Animals , Body Weight , Particle Size , Time FactorsABSTRACT
Cadmium uptake rates in various tissues of Pandalus montagui exposed to sea water containing 37 micrograms Cd/L for 14 days ranged from 0.002-0.06 microgram/dry tissue/hr. During depuration for 57 days, the levels in most tissues decreased slightly, but continued to rise in the hepatopancreas indicating Cd redistribution. Exposure to 65 micrograms Zn/L produced no substantial change in Zn content of the tissues. An increase occurred in eggs and hepatopancreas during the first six days of depuration. During exposure to Cd and Zn combined (40 micrograms Cd/L + 70 micrograms Zn/L), tissue Zn levels responded as with Zn alone. In the presence of Zn, Cd concentration was doubled in the hepatopancreas, depressed by one-third in the carcass, and did not change in the other tissues. Increased amounts of Zn (up to 410 micrograms Zn/L) had not effect on the Cd levels of the tissues except that the Cd level in the hepatopancreas was depressed, although the level was still greater than in the case of exposure to Cd alone. The possible role of metallothionein is discussed.
