TOXICOLOGY AND APPLIED PHARMACOLOGY 140, 39–50 (1996) ARTICLE NO. 0195 Toxicokinetics and Disposition of Inorganic Mercury and Cadmium in Channel Cat®sh after Intravascular Administration

1988). Numerous studies have described the high toxicity Toxicokinetics and Disposition of Inorganic Mercury and Cad- of these metals to fishes after acute and chronic exposures mium in Channel Cat®sh after Intravascular Administration. (reviewed in Mance, 1990). Uptake and accumulation stud-SCHULTZ, I. R., PETERS, E. L., AND NEWMAN, M. C. (1996). Tox- ies of inorganic mercury and cadmium in fishes have de-icol. Appl. Pharmacol. 140, 39±50. scribed the relatively slow absorption and low bioavailability To better understand the distribution and elimination of inor- of these metals from water or food and the importance of ganic mercury (Hg) and cadmium (Cd) in ®shes, channel cat®sh both administrative routes in determining the accumulation (Ictalurus punctatus) were administered either 6.4. mg/kg 203Hg as of these metals (Olson et al., 1973; Williams and Giesy, HgCl2 or 4.0 mg/kg 109Cd as CdCl2 via a dorsal aortic cannula. 1978; Huckabee et al., 1979; Stary et al., 1981; Norrgren et Blood, plasma, and red blood cells (RBCs) were serially sampled al., 1985; Borg et al., 1988; Harrison and Klaverkamp, 1989;up to 156 (Hg) or 335 (Cd) days. The fraction of the injected dose Glynn, 1991). The disposition of inorganic mercury and cad-remaining in the animal (Xf) was also determined at selected times mium in fishes has been characterized after water, oral, andby whole animal counting. The blood concentration and Xf±time ip administration, with the pattern of tissue distribution vary-pro®les were simultaneously ®tted to a three-compartment toxico-ing depending on the administrative route. Regardless of thekinetic model. The plasma concentration±time pro®le was also separately ®tted to the same three-compartment model for com- exposure route, the liver and kidney tended to accumulate th