Detectable interactions between NOEL (No Observed Effect Level) doses of Pb, Hg and
Cd in general toxicological, hematological, and immune function parameters were investigated.
The metals (Pb-acetate, 20 mg/kg; HgCl 2, 0.40 mg/kg; CdCl2, 1.61 mg/kg) were combined.
First, the rats received the combination Pb + Hg + Cd for 4 weeks per os. Significant
difference vs. control was found only in the weight of lung and popliteal lymph node
(PLN). The Pb + Hg and Pb + Cd combinations significantly decreased the PLN to 100
g body weight and PLN to brain weight ratio, and Pb+Hg also decreased the relative
adrenal weight. After 12 weeks treatment with the same doses, effects on the thymus,
kidney, and adrenal weights in the Pb + Hg, and thymus weight in the Pb + Cd, combination
were seen. Pb + Cd also affected the white and red blood cell count and hematocrit.
Combined with Hg or Cd, NOEL dose Pb showed toxicity, indicating that exposure limits
may be inefficient in combined exposure situations. ÂŠ 2006 AkadĂŠmiai KiadĂł.