Aftereffects of ferromagnetic screening on the hematological and toxicogenomic parameters in rats were traced over 45 days. Two-day ferromagnetic screening of male and female rats (reducing permanent constituent of magnetic field induction by 4-10 μT) led to leukopenia observed on day 14 of the experiment. Life-time evaluation of the toxicogenomic effects was carried out by rapid method for measurement of blood nucleotide DNA by fluorescent indication. In male blood leukocytes, increased aneuploidy and polyploidy were observed after 48 h of ferromagnetic screening and remained high on days 12 and 28 after screen removal. In contrast to males, leukocyte apoptosis in females was increased only 48 h after the start of ferromagnetic screening.