Page 920 - The Toxicology of Fishes

900 The Toxicology of Fishes

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9 Reference *
8 7 ConA 11
Stimulation Index (SI) 6 5 4 10 10

*
*

2 3 10
10 10 10 9
1
0
Day 3 Day 7 Day 15 Day 32
Time (days) after injection
FIGURE 22.15 Stimulation indices of splenic leukocytes from English sole injected with Eagle Harbor Sediment extract
( ) or with the carrier acetone/Emulphor EL-620 ( ). The LP response of the sole to the mitogen, concanavalin A, was
determined on days 3, 7, 15, and 32 after injection. The stimulation index was determined for each individual fish. The
asterisk (*) signifies that the EHSE-injected fish produced a significantly different leukoproliferative response than that
produced by fish injected with acetone/Emulphor EL-620. The vertical bars represent 1 SE above and below the mean.
Mean tritium disintegrations per minute (±SE) of splenocytes from control cultures (without mitogen) ranged from 130 ±
20 to 520 ± 200. (Adapted from Clemons, E. et al., Mar. Env. Res., 47, 71–87, 2000.)

6
nmols O2 Produced/2 × 106 MO 5 *
*

4
3
2
1

0
1 day 3 day 7 day 14 day
Days Post Treatment Injection
FIGURE 22.16 Amounts of superoxide produced (mean + SD) by elicited peritoneal macrophages from uninjected English
sole ( ), sole injected with acetone/Emulphor EL-620 ( ), or sole injected with sediment extract ( ) stimulated with opsonized
zymosan (OZ) in vitro at 1, 3, 7, and 15 days after exposure to PAHs. Six fish per treatment per day are represented, except at
day 3 there are 5 fish from the sediment-extract-injected group and at day 14 each treatment group is represented by 7 individuals.
The asterisk (*) signifies that the sediment-extract-injected group is significantly different (p < 0.05) from either the uninjected
group or the group injected with acetone/Emulphor EL-620. (Adapted from Clemons, E. et al., Mar. Env. Res., 47, 71–87, 2000).

corresponding hatcheries or from nonurban estuaries. Furthermore, concentrations of plasma hormones
involved in the regulation of growth in fish, such as thyroxine (T ), triiodothyronine (T ), and insulin-
4
3
like growth factor (IGF), were altered in salmon from urban estuaries in comparison with hormone levels
in hatchery or non-urban fish (Casillas et al., 1995, 1998a, unpublished data). These findings suggest
that exposure to PAHs and other organic contaminants may interfere with the endocrine modulation of
growth in juvenile salmon, resulting in impaired overall growth.
Laboratory exposure experiments with model compounds and sediment extracts from contaminated
Puget Sound sites also indicate that exposure to PAHs may suppress growth or alter the metabolism of