James Gottofrey

Tissue disposition of 109cd2+ in the brown trout (Salmo trutta) studied by autoradiography and impulse counting †

Brown trouts, Salmo trutta, were exposed to 109Cd2+ in concentrations of 0.1, 0.5, 1.0 and 10.0 μg/1 in aquarial water during 1 or 2 weeks. The disposition of the 109Cd2+ in the tissues was then examined by whole‐body autoradiography and gamma spec‐trometry. The tissues accumulating the highest levels of 109Cd2+ were the olfactory apparatus, the gills and the trunk kidney. The autoradiography showed that in the olfactory apparatus there was a labelling of the epithelium of the olfactory rosette, the olfactory nerve and the anterior part of the olfactory bulb of the brain. The cadmium is probably taken up in the nerve cells in the olfactory epithelium and transported via axonal transport to the axonal terminations in the olfactory bulb of the brain. The 109Cd2+ in the gills comprised from about 75% to about 40% of the total body burden of the metal, the highest proportions being present at the lowest cadmium concentrations in the water and at the 1 week exposure interval. The 109Cd2+ in the kidney, which w...

Effect of lipophilic complex formation on the uptake and distribution of Hg2+ and CH3-Hg+ in brown trouts (Salmo trutta) : studies with some compounds containing sulphur ligands

Brown trouts, Salmo trutta, were exposed via aquarial water to 203Hg2+ or to CH3−203Hg+ alone or together with one of the following S-containing substances: sodium dimethyldithiocarbamate (SMC), sodium diethyldithiocarbamate (SEC), potassium ethylxanthate (PEX), sodium isopropylxanthate (SIX), sodium diethyldithiophospbate (SEP), sodium diisopropyldithiophosphate (SIP) or sodium pyridinethione (SPyr). The distribution of the 203Hg2+ and the CH3−203Hg+ in the fishes were then studied by whole-body autoradiography and gamma spectrometry. The results showed that the examined complexing substances can induce increased uptake of both 203Hg2+ and CH3−203Hg+ by the fishes: for 203Hg2+ most of the complexing substances induced a similar increase in various tissues; for CH3−203Hg+ marked variations were seen for different substances. Determinations of chloroform/water partition coefficients showed that the examined substances are able to form lipophilic complexes both with Hg2+ and CH3−Hg+. A facilitated penetration of the lipophilic complexes over the membranes of the gills and other tissues may underly the increments of the tissue-levels of the Hg. It is possible that increased uptake of Hg2+ and CH3−Hg+ induced by complexing substances of this type may have toxicological implications for fishes and for other aquatic organisms.

Effects of some chelating agents on the uptake and distribution of 203Hg2+ in the brown trout (Salmo trutta): studies on ethyland isopropylxanthate, diethyl- and diisopropyldithiophosphate, dimethyl- and diethyldithiocarbamate and pyridinethione

Brown trout, Salmo trutta, were exposed to water containing 0.1 μg/l 203Hg2+, alone or with potassium ethylxanthate (PEX), sodium isopropylxanthate (SIX), sodium diethyldithiophosphate (SEP), sodium diisopropyldithiophosphate (SIP), sodium dimethyldithiocarbamate (SMC), sodium diethyldithiocarbamate (SEC) or sodium pyridinethione (SPyr), respectively. After 1 week the uptake and distribution of the 203Hg2+ in the fish were examined by gamma spectrometry. SIX, SIP, SMC, SEC and SPyr induced 2–3 times higher 203Hg2+ concentrations in most tissues in comparison with trout exposed to 203Hg2+ only. In the trout exposed to PEX slightly enhanced 203Hg2+ levels were found only in some tissues, and after exposure to SEP a few tissues showed decreased 203Hg2+ concentrations. Determinations of chloroform/water partition coefficients showed that lipophilic chelates are formed between all the examined substances and the 203Hg2+. However, SIX, SIP, SMC, SEC and SPyr, which induced markedly increased tissue levels of the metal, formed 203Hg2+ complexes with higher lipophilicities than SEX and SEP. A facilitated penetration of the lipophilic 203Hg2+ complexes over the gill membranes may underly the increment in the tissue levels of the metal, and the relative lipophilicity of the complexes may be of importance for this effect. In some instances, as with SEP, the 203Hg2+ chelated in complexes with low lipophilicity may even be less able to acumulate in some tissues than the non-complexed metal.

Effect of sodium isopropylxanthate, potassium amylxanthate and sodium diethyldithiocarbamate on the uptake and distribution of cadmium in the brown trout (Salmo trutta)

Abstract Brown trout, Salmo trutta , were exposed to water containing 1 μg/l of 109 Cd 2+ , alone or with sodium isopropylxanthate, potassium amylxanthate or sodium diethyldithiocarbamate, respectively. After one week the uptake and distribution of the 109 Cd 2+ in the fish were examined by whole-body autoradiography and gamma spectrometry. Sodium diethyldithiocarbamate was found to enhance the uptake of the 109 Cd 2+ in several tissues of the fish and this effect increased with increasing concentration of the carbamate. Potassium amylxanthate induced increase in the levels of 109 Cd 2+ in several tissues, whereas the brain was the only tissue with increased concentration of 109 Cd 2+ in the presence of sodium isopropyl-xanthate. A likely mechanism for the enhanced uptake of the 109 Cd 2+ may be a facilitated penetration over the gill membranes of the lipophilic complexes formed between the studied compounds and the cadmium. A facilitated passage through cellular membranes may also be important for the increased uptake of the metal in other tissues. An elevated uptake of cadmium by the xanthates or the diethyldithiocarbamate may constitute an increased risk for noxious effects of the metal.