Showing papers on "Zinc toxicity published in 1972"
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TL;DR: Tissue hypoxia appears to be a major physiological change preceding death once the gas exchange process at the gills is no longer sufficient to supply the oxygen requirements of the fish.
Abstract: Acute heavy metal toxicity to fish has been attributed to the coagulation or precipitation of mucus on the gills and/or to cytological damage to the gills The physiological mechanism of death by either of the above causes is related to a breakdown in gas exchange at the gills This study of acute zinc toxicity to rainbow trout (Salmo gairdneri) supports an earlier hypothesis that modification of the gas exchange process at the gills creates hypoxia at the tissue level Tissue hypoxia appears to be a major physiological change preceding death once the gas exchange process at the gills is no longer sufficient to supply the oxygen requirements of the fish
125 citations
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TL;DR: Levels of zinc from 3,000 to 12,000 ppm were fed to domestic mallard ducks (Anas platyrhynchos) in their diet to determine the hazard of zinc as an environmental pollutant to waterfowl.
Abstract: Levels of zinc from 3,000 to 12,000 ppm were fed to domestic mallard ducks (Anas platyrhynchos) in their diet. Food intake and body weight both showed closely parallel decreases as the level of zinc in the diet increased. In ducks fed zinc, the pancreas and gonads underwent reductions in relation to body weight, whereas ratios of adrenals and kidneys to body weights increased significantly. No significant change occurred in liver:body weight ratios in ducks fed zinc-supplemented diets. The gonads were so reduced in size that the reproductive function was probably lost. In birds fed zinc-supplemented diets, partial paralysis of the legs, diarrhea, and weight loss were noted within 1!0 days. Severe paralysis, with some ducks unable to waLk, was noted after 20 days. Only slight anemia was present in some ducks after 30 days, but by day 45, extreme anemia (5-13 grams Hb per 100 cc of blood) was evident in most ducks. Normal hemoglobin concentrations averaged 18.6 grams per 100 cc of blood. Significant increases in concerltrations of zinc were found in the liver, kidneys, pancreas, gonads, and breast muscle. High mortality was observed in all groups treated with zinc-supplemented diets; all but 2 of 24 ducks died within 60 days. Paralysis of the legs, high concentrations of zinc in the pancreas and kidneys, and yellowish-red kidneys may be used for diagnosing zinc toxicosis in mallards. Heavy metals such as lead, mercury, copper, and zinc have long been known for their toxicity to animals. Copper and zinc are required as trace elements in the diets of animals, but when they occur in relatively high levels, they become toxic. In this particular set of experiments, toxicity of zinc was studied in domestic mallard ducks to determine the hazard of zinc as an environmental pollutant to waterfowl. This study stems from 70 years of observations, summarized by Chupp and Dalke (1964), of dead and dying ducks, geese, and swans in the Coeur d'Alene Lake area in northern Idaho where zinc is found in high concentrations. The Coeur d'Alene area has been actively mined for at least 70 years and effluents from mines and smelters have been poured into the river systems of the area. These wastes then flow downstream, settling in 1 This investigation was supported by the Society of the Sigma Xi and the senior author's National Defense Education Act Fellowship. 2 Present address: Institute of Arctic Biology, Fairbanks, Alaska. the rivers and lakes, where the aeeumulation of metals beeomes high. Lewis and Deneeke (1923) found 2.86 pereent lead in a sediment sample eolleeted in the Coeur d'Alene valley. Ellis (1940) found a range of 5 to 12 pereent zine in soil enerustations. Chupp and Dalke ( 1964 ) analyzed 12 soil samples (type not stated) and obtained from 150 to 9,600 ppm lead, 240 to 7,700 ppm zine, and 31 to 320 ppm eopper. Three samples of emergent aquatie plants (species not stated) mrere analyzed from which an average of 2,530 ppm lead, 1,930 ppm zine, and 115 ppm eopper were found. As a result, waterfowl that feed in these areas eonsume larger amounts of heavy Inetals than waterfowl feeding in areas of naturally low ( normal ) eoncentrations. Die-offs of dueks, geese, and whistling swans (Olor colaznbianus) have been noted in this area sinee the early 1900's (Chupp and Dalke 1964); however, these die-offs have been variable, oeeurring only in some years. Chupp and Dalke indicated that their tissue analyses for heavy netals and the early studies by the Bureau
102 citations
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TL;DR: A review of the medical toxicology of cadmium, cobalt, selenium, arsenic, nickel, copper, manganese, tellurium, vanadium, molybdenum, zinc, and tin; emphasis is on industrial sources of these metals.
Abstract: A review of the medical toxicology of cadmium, cobalt, selenium, arsenic, nickel, copper, manganese, tellurium, vanadium, molybdenum, zinc, and tin; emphasis is on industrial sources of in...
70 citations
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TL;DR: Experimental haemodialyses of dogs against small concentrations of zinc showed a disproportionate rise in plasma zinc and possible uptake of zinc by the liver, and a country patient on home haemmodialysis was found to have severe anaemia with raised plasma and erythrocyte zinc concentrations.
Abstract: A country patient on home haemodialysis suffered acute nausea, vomiting, and fever during dialyses when she used water stored in a galvanized tank. She subsequently was found to have severe anaemia with raised plasma and erythrocyte zinc concentrations. Intercurrent hospital haemodialyses and subsequent home dialyses with deionized water were symptom-free. Experimental haemodialyses of dogs against small concentrations of zinc showed a disproportionate rise in plasma zinc and possible uptake of zinc by the liver.
69 citations
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01 Feb 197223 citations
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TL;DR: Replacing increments of sucrose in a sucrose-fish meal ration with ground corn caused a linear decrease in zinc toxicity, and similar dietary effects were not found for toxic levels of selenium, fluorine or molybdenum.
7 citations