TABLE 1. — Residues of benzene and toluene and/or metabolites (mean nl/g±SE) accumulated during and after a 48-h 

 exposure to 100 nl/liter (ppb) 14 C benzene or 100 nl/liter (ppb) 14 C toluene in the tissues of Clupea harengus pallasi. 

 Number of samples in parentheses. 



Gallbladder: 

 Benzene 



Toluene 



Intestine: 

 Benzene 



Toluene 



Pyloric caeca: 

 Benzene 



Toluene 



Gill: 



Benzene 



Toluene 



Brain: 

 Benzene 



Toluene 



Liver: 

 Benzene 



Toluene 



Muscle: 

 Benzene 



Toluene 



Kidney: 

 Benzene 



Toluene 



Gonad: 

 Benzene 



Toluene 



0.37±0.075 2.1-0 71 3.1 ±0.48 



(4) (5) (5) 

 4.6±3.4 30 ±11 27±15 



(5) (5) (5) 



2.7+1.5 



(3) 



34±17 



(5) 



0.83±0.78 0.42±0.28 0.61 ±0.55 0.16 



(4) (5) (5) (1) 

 3.9±2 4 2.3±2.1 2.1 ±1.7 0.70±0.7 



(5) (4) (5) (5) 



0.56±0.30 0.92±0.79 0.60±0.14 0.61 



(3) (4) (4) (1) 



19±9.0 1.7±095 0.24-0.49 6.0 ±4.9 



(5) (5) (3) (2) 



— 2 0.087 0081 



(D (1) 



0.09±0.014 0092±0013 .1 1 ±0.025 0.13±070 



(2) (3) (2) (3) 



058 ±0 34 63 ±0 38 64 ±0 38 095 ±0 039 — 056 — — 



(5) (5) (5) (3) (1) 



3 6±3 6 1.8±0.32 2.4±1.4 0.77 ±0.46 0.23 ±0.94 0.13±0.03 0.11 ±0.037 0.16±0.081 



(5) 



(5) 



(5) 



(5) 



(5) 



(5) 



(5) 



(4) 



0068 



(1) 



0.51 ±0.12 0.61 ±0.33 0.73±0.46 073 



(5) (5) (5) (2) 



1.8 ±0.58 1 2 ±1.2 1.0±0.96 0.20±0 12 



(5) (5) (5) (5) 



0.742:0.11 075±014 0.62±0.052 59 



(5) (5) (5) (2) 



2.1 ±0.19 2.0±0.28 1.5±0.18 0.13±0.073 



(5) (5) (5) (3) 



0.45 ±0.070 0.53 ±0.096 0.50 ±0.067 — 



(5) (5) (4) 



1.5±044 1.4±0.44 1.2±0.13 0.36±0.15 0.23±005 



(5) 



(5) 



(5) 



(5) 



(4) 



0.41 ±0 22 0.63±0.36 0.44±0.33 035 



(5) (5) (4) (1) 



1.3 ±0.80 52±0.28 0.66±0.71 0.33 



(5) (5) (5) (2) 



0.32±0.066 0.32±0.066 0.40±0 .12 — 



(5) (5) (5) 



13±0 50 1.1 ±0.40 0.75 ±0.33 18±0099 



(5) (5) (5) (4) 



0.15±0.021 0.24±0.062 0.21 ±0.10 — 



(5) (5) (5) 



0.43 ±0.24 0.44±0.21 0.44 ±0.28 16 



(5) (5) (4) (1) 



066 



(1) 



'Exposure terminated after 2 days; then fish remained in flowing seawater for 5 days 

 2 — = nondetectable levels 



Residues were depurated rapidly, with most tis- 

 sues having nondetectable amounts after 3-4 days 

 (1-2 days after termination of exposure). The 

 gallbladder, intestine, and pyloric caeca retained 

 residues through the duration of the study (7 

 days). 



In the experiment in which gas chromato- 

 graphic analyses were performed on the gallblad- 

 der, no detectable benzene (<0.1 nl/g) was mea- 

 sured. Gas chromatography analysis resulted in 

 only 0.56-1.5 nl/g toluene. This indicates that 

 most or all of the radioactivity measured by liquid 

 scintillation in the gallbladders offish exposed to 

 benzene is not the parent compound, but one or 

 more metabolites. Fish exposed to toluene had a 

 small amount of the parent compound as opposed 



to metabolites (1.5 nl/g toluene maximum, com- 

 pared with 27 nl/g expected [Table 1]). 



The above result and the occurrence of delayed 

 depuration in the gallbladder, intestine, and 

 pyloric caeca supports the contention that benzene 

 and toluene are metabolized in the liver, stored in 

 the gallbladder, then passed into the intestine and 

 are excreted with the feces. This agrees with 

 Roubal et al. (in press) who found high levels of 

 benzene metabolites in the liver and gallbladder of 

 salmon which had previously received in- 

 traperitoneal benzene injections. This also agrees 

 with our previous results with benzene in other 

 fishes (Korn et al. 1976), results of Neff (1975), and 

 with work by Lee et al. (1972) who demonstrated 

 metabolism of polycyclic aromatics in the liver 



635 



