Preliminary investigations on the influence of suspended sediments on the bioaccumulation of two chlorobenzenes by the guppy (Poecilia reticulata)

Uptake of 1,2,3-trichlorobenzene (TCB-125 ug per litre) and hexachlorobenzene (HCB-1.5 ug per litre) by the guppy (Poecilia reticulata) from sediment-free water and from water containing suspended sediment was studied in 3 simultaneous experiments involving 30 fish and 2450 mg (dry weight) of sediment (A), 2450 mg (dry weight) of sediment only (B), and 30 fish only (C) during a 290 h period. Experiment B was a control for the loss of chemicals by volatilization or degradation by micro-organisms. TCB uptake was not significantly influenced by the presence of suspended sediment (20 and 23 mg per g fish for experiments A and C, respectively), due to the large amount of TCB dissolved relative to the amount present in the sorbed state. HCB concentration was significantly higher in fish from the system with suspended sediment (0.5 ug per g after 290 h compared with 0.2 ug per g fish in experiment C).