Submitted to: Journal of Federation of American Societies for Experimental Biology
Publication Type: Abstract Only
Publication Acceptance Date: 12/10/1999
Publication Date: 3/15/2000
Citation: Reeves, P.G., Chaney, R.L. 2000. Nutrient status affects the absorption of cadmium from sunflower kernels [abstract]. The Federation of American Societies for Experimental Biology Journal. 14:A750. Interpretive Summary:
Technical Abstract: Dietary intake of small amounts of cadmium (Cd) over time can increase the body burden of this element. It has been observed that some human populations that consume subsistence rice-based diets low in calcium (Ca), iron (Fe) and zinc (Zn) seem to be more susceptible to Cd poisoning than populations that consume more nutritious diets. The present study determined the effects of marginal deficiencies of these essential elements on the absorption and organ retention of Cd from sunflower kernels (SFK). SFK contain higher Cd (0.2 -1.0 mg/kg) than most other grains (<0.1 mg/kg); however, they also contain higher amounts of Fe and Zn. Female rats were fed diets with 20% SFK in a 2x2x2 factorial design with marginal and adequate Ca, Zn, and Fe. Zn (11 mg/kg) and Fe (14 mg/kg), and Cd (0.18 mg/kg) were derived solely from 20% SFK. These amounts of Fe and Zn represented 40 and 90% of the NRC requirement for the rat, respectively. Ca concentration (2.5 g/kg) was 1/2 the NRC requirement After 5 wk on experiment, rats were fed 1 g of their respective diets containing SFK extrinsically labeled with 37 kBq 109Cd, and absorption was determined by whole body counting techniques. Rats were then killed and organs collected for 109Cd assay. There was no effect of treatment on weight gain; however, feeding marginal Ca elevated Cd absorption by 50% (p<0.05) over those fed adequate Ca. Marginal Fe elevated Cd absorption 170% (p<0.001) over those fed adequate Fe. In contrast, Zn in SFK that provided 90% of the rat's requirement was enough to deter excessive absorption of Cd. Organ content of 109Cd followed a similar pattern as whole body absorption. These data show that marginal deficiencies of Ca and Fe can readily enhance the body burden of Cd that comes from the diet.