The effect of Pb and Cd uptake on Zn and Cu levels in hard and soft tissues of rats†

This paper is a follow‐up of the paper entitled “Lead and Cadmium in the Teeth, Bone and Kidneys of Rats with a Standard Pb‐Cd Supply.” (Intern. J. Envir. Studies, in press.)

Abstract

Male Wistar rats received a combination of 25 ppm PbCl₂ and 5 ppm CdCl₂ in drinking water at different developmental stages. Zn and Cu levels of incisors, molars, epiphyses, diaphyses and kidney cortex were recorded by atomic absorption spectrophotometry. Pb‐Cd uptake in rats, either via the mother through placenta or mammae, or directly in growing rats resulted in an overall decrease in Zn content of epiphyses. This may cause a decreased growth rate. There was a significant negative correlation between Pb and Zn in epiphyses. In addition, an increase in the Zn level of kidney cortex was found in the animals receiving Pb‐Cd from weaning until sacrifice, and through all stages there was a significant positive correlation between Zn and Cu in this tissue. Pb‐Cd administration during pregnancy and/or lactation resulted in an increased storage of Cu in hard as well as soft tissues of the offspring. This storage did not take place if Pb‐Cd were given after termination of the lactation period. There was a positive significant correlation between Pb and Cu in incisors and molars, and between Cd and Cu in incisors, molars, epiphyses and diaphyses. It was not possible in this study to determine whether the effect on Zn and Cu tissue levels was a result of Pb or of Cd, or if the effect was caused by the supply of the two elements in combination.

Notes

This paper is a follow‐up of the paper entitled “Lead and Cadmium in the Teeth, Bone and Kidneys of Rats with a Standard Pb‐Cd Supply.” (Intern. J. Envir. Studies, in press.)