Air Quality Criteria for Lead Volume II of II - (NEPIS)(EPA) - US ...

Fish
The general symptoms of Pb toxicity in fish include production of excess mucus, lordosis,
anemia, darkening of the dorsal tail region, degeneration of the caudal fin, destruction of spinal
neurons, ALAD inhibition, growth inhibition, renal pathology, reproductive effects, growth
inhibition, and mortality (Eisler, 2000). Toxicity in fish has been closely correlated with
duration of Pb exposure and uptake (Eisler, 2000). The following presents information on the
toxicity of Pb to fish in fresh and marine waters. Table AX7-2.4.2 summarizes the effects of Pb
on freshwater and marine fish.
Freshwater Fish
Many of the toxicity modifying factors described above and in Section AX7.2.3.5 (e.g.,
pH, DOC) for invertebrates are also important modifying factors for Pb toxicity to fish species.
The effects of pH on Pb bioavailability and subsequent toxicity have been well-studied (Sayer
et al., 1989; Spry and Wiener, 1991; Schubauer-Berigan et al., 1993; Stouthart et al., 1994;
MacDonald et al., 2002; Rogers and Wood, 2003). Schubauer-Berigan et al. (1993) exposed
fathead minnow to Pb-chloride over 96 hours. The reported LC50 ranged from 810 to
>5400 µg/L at pH 6 to 6.5 and pH 7 to 8.5, respectively.
Water hardness also has a strong influence on the effects of lead to fish. Chronic
exposure of rainbow trout fry to Pb in soft water resulted in spinal deformities at 71 to 146 µg/L
after 2 months of exposure (Sauter et al., 1976) or 13.2 to 27 µg/L (Davies and Everhart, 1973;
Davies et al., 1976), after 19 months of exposure. When exposed to Pb in hard water, only 0 and
10% of the trout (Oncorhynchus mykiss) developed spinal deformities at measured Pb
concentrations of 190 and 380 µg/L, respectively. In soft water, 44 and 97% of the trout
developed spinal deformities at concentrations of 31 and 62 µg/L, respectively (Davies et al.,
1976). The maximum acceptable toxicant concentration (MATC) for rainbow trout fry in soft
water was 4.1 to 7.6 µg/L (Davies et al., 1976), while the MATC for brook trout was 58 to
119 µg/L (Holcombe et al., 1976). Histological reproductive abnormalities were noted in mature
male rainbow trout at 10 µg/L Pb-nitrate (Ruby et al., 1993).
Schwartz et al. (2004) examined the influence of NOM on Pb toxicity to rainbow trout
exposed for 96 h in a static system. The pH of the exposure system ranged between 6.5 and 7.0,
temperature was maintained between 9 and 11 ΕC, and Pb was added as PbCl2. NOM from a
AX7-189