Bio-accumulation of some heavy metals in blood serum of residents in Isfahan and Shiraz, Iran.

In this study, some heavy metal (Cd, Pb, Ni, Fe, Co, Cr, Mn, Cu, and Zn) concentrations were measured in the blood serum samples of 25 patients who suffered from the multiple sclerosis (MS) disease living in two industrial regions of Isfahan, Iran, using inductively coupled plasma (ICP) instrument. Also, blood serum levels of heavy metals in 25 healthy people of Isfahan and 25 healthy people of Shiraz were analyzed as controls. In industrial regions, some of the heavy metals were also measured in the soils and food crop samples (wheat, rice, and onion). The results showed that the blood serum levels of Cd, Co, Ni, and Pb of MS patients (0.032, 0.56, 1.60, and 2.90 μg L(-1), respectively) were significantly higher than those of healthy people. These values exceeded the permissible ranges that are 0.08-0.50, 0.14-1.0, and 0.80-2.50 μg L(-1) for the Co, Ni, and Pb, respectively. The mean concentrations of Fe and Zn in the blood serum of MS patients (529 and 547 μg L(-1)) were significantly lower than those in the healthy people and also less than the acceptable ranges (700-1700 and 660-1100 μg L(-1), respectively). The target hazard quotients of Pb (2.23) and Cd (1.25) via wheat and Pb (1.34) via rice consumption were higher than one. Therefore, it is proposed that consumption of local contaminated food crops may have drastically increased the concentrations of heavy metals in the human blood serum of inhabitants of industrial regions.