Cadmium Accumulation by Meadow Voles (Microtus Pennsylvanicus) from Crops Grown on Sludge‐treated Soil

Abstract

AbstractThis investigation was conducted to measure the accumulation of cadmium (Cd), zinc (Zn), and copper (Cu) in the tissues of the meadow vole (Microtus pennsylvanicus) fed organic and inorganic cadmium. Corn (Zea mays L.) and sorghum (Sorghum bicolor L. Moench) plants were grown on soils fertilized with either inorganic or sludge fertilizer. Corn herbage fertilized with sludge was found to contain 1.82 ppm Cd and sorghum herbage contained 4.59 ppm Cd. Herbage from inorganic fertilized plots contained 0.17 ppm and 0.38 ppm Cd, respectively. Eight diets and a synthetic control diet were formulated to study these herbages. Cadmium sulfate was added to four of the diets to evaluate the effect of organic plant Cd and soluble Cd on accumulation in vole tissue. Each diet was fed to 10 animals for a period of 40 days and kidney, liver, and muscle tissue were analyzed for Cd, Zn, and Cu.Significant accumulation of Cd occurred in kidneys and livers, but not in muscles of voles fed sludge‐fertilized corn diets with 1.09 ppm Cd or sorghum diets with 2.76 ppm Cd. The form of Cd, whether organic or soluble, had little influence on tissue accumulation. Zinc and Cu accumulation in these tissues was, in most cases, nonsignificant and not associated with Cd accumulation. Weight gain, food intake, and diet digestibility were not influenced by Cd accumulation in the tissue, but the daily intake of Cd was a function of the concentration of Cd and fiber in the diet. It was concluded that diets containing 1.00 ppm Cd may cause significant accumulation of Cd in animal tissues.