Accumulation trends and patterns of some heavy metals in liver of Wistar rats following exposure to contaminated water

Abstract

Heavy metals are known to cause damage through indirect oxidative effects. A comparative study on the bioavailability and liver accumulation of lead (Pb), cadmium (Cd), and mercury (Hg) in rats following continuous exposures to Hg (10 ppm), Cd (200 ppm) and Pb (100 ppm) in drinking water was carried out for six weeks. The accumulations in the liver were determined using AAS. Analysis gave evidence that the rate of change was not the same for all three metals for all three periods of time; there was statistically (p<0.05) significant interaction between the types of metal and time in their relationship to levels accumulation of the metals. While Hg and Pb showed peak accumulation at the second week of exposure, there was decrease in accumulation by the fourth and sixth week. Cd on the other hand showed a continuous increase in accumulation over the six weeks of study. Results indicate that the heavy metal concentration in the liver is under some physiological control, which may involve the chemistry of these metals resulting in different uptake, accumulation and elimination rates from the liver.

Keywords: cadmium, lead, mercury, liver, accumulation pattern