Comparative effect of water and food-chain mediated cadmium exposure in rats

Abstract

This study sets out to compare the absorption and toxicity of Cadmium (Cd) administered via the food-chain and inorganic Cd administered in drinking water after 1 and 3 months exposure using rats as animal model. The food-chain was mimicked by exposing rats to diet containing Cd pre-exposed fish. The uptake of Cd by the rats after both mode of exposure was calculated by summing up the Cd burden in the liver and kidneys and was expressed in terms of % intake. The toxicity of Cd was assessed by monitoring biochemical indices of liver function in the plasma and liver. Regardless of the mode of exposure of the rats, the Cd load in the liver and kidney was significantly (P < 0.05) higher than the respective controls with the kidney having a significantly higher load than the liver after both periods of exposure. However irrespective of the mode of exposure, more Cd was accumulated in the liver and kidney of the 3 months exposed rats relative to those exposed for 1 month. The uptake of Cd by rats exposed to Cd via the food-chain for 1 and 3 months was significantly (P< 0.05) lower when compared to the corresponding water mediated Cd exposed rats, except for the liver after 3 months of exposure. The liver L-ALT activity of rats administered inorganic Cd in drinking water for 1 and 3 months was significantly (P < 0.05) lower as compared to controls. Parallel analysis of the plasma showed no significant (P > 0.05) difference in L-ALT activity between both groups after the same periods of exposure. The L-AST activity in the plasma of rats similarly exposed to Cd for 1 and 3 months was significantly (P < 0.05) higher as compared to controls with a corresponding reduction in the liver. Conversely no significant (P > 0.05) change was observed in plasma and liver L-ALT and L-AST activities after food-chain mediated exposure to Cd for 1 and 3 months in relation to their respective controls. These findings indicate that Cd incorporated in fish is more easily bioavailable, but less toxic relative to inorganic Cd salts at the end of 3 months of exposure in rats.

Long-term effect of diet amended by risk elements contaminated soils on risk element penetration and physiological parameters of rats

“…The effect of risk element uptake on body weight and weight gain of rats was investigated by Paul et al (2002) in the case of arsenic, Asagba (2010) in the case of cadmium, Smith et al (2008) and Shan et al (2009) and in the case of lead. Whereas animal exposure to arsenic and lead did not result in the animal growth suppression regardless of element rate and experiment duration, suppressed animal growth was observed after dietary cadmium exposure of rats.…”

Protective Effects of Selenium on Hepatotoxicity Caused by Subacute Experimental Combined Exposure to Cadmium and Lead in Rats

“…The lowest water consumption was observed in the case of the Cd+Pb+Se group. Some studies have also reported decreased fluid intake in case of cadmium or lead exposure [8,39], while other studies did not [41,59]. One cause for the decrease in fluid intake, when the drinking water contains cadmium and/or lead can be the alteration of taste.…”