ALAD and anemia (phenotype): Lead is more likely to interact with δ-aminolevulinic acid dehydratase (ALA-D), xanthinogen oxidase (XOD) and iron chelatase (FC) by inhibiting the synthesis of heme and cytochrome [26–28] thus leading to the decrease of hemoglobin, the phosphatidylserine exposure of membrane surface, the shrinkage of erythrocyte [29] and decrease of volume, as well as the appearance of anemia-like morphological changes [27, 28], eventually causing a significant increase of the characteristic frequency (f1, f2, and f0) of RBCs [30].