Background: Nowadays, iron nanoparticles and other nanomaterials are widely used in many fields including industrial and biomedical fields. Yet many concerns remain about their fate and toxicity to living organisms. Objective: The aim of the current study was to evaluate the risk of using iron oxide nanomaterials as food additives for animals to increase its utilization compared to bulk size particles of the same material. Materials and Methods: The study included the effect of two different nano-sized iron oxides (25 nm and 50 nm) at two doses (1 mg/kg feed and 10 mg/kg feed) on some biological and hematological parameters in male albino rats. Results: The results indicate that rat’s performance, growth, feed conversion rates were not affected with no sign of toxicity. Most of the hematological parameters in all treated groups were not affected by IONPs except one group which showed a significant difference in the percent of granulocytes compared with the control. Conclusion: It can be concluded that iron oxide NPs of different sizes and doses did not affect their performance, growth rate, hematological parameters with no sign of toxicity. Keywords: Iron Nanoparticles, Biological and hematological, Rats.

ABSTRACT:2-Hydroxy Chalcone and its derivatives (compounds 1and 2) were used in a toxicity test on the larvae and adults of confused flour beetle Tribolium confusum (Du Val). Mortality tests were done by applying different concentrations (0.01, 0.02 and 0.04 ppm) on2-Hydroxy Chalcone and its derivatives whichwere exposed by topical application with 5 μL of each compound and the data wererecorded after 24 h of treatments. The mortality % of[7-Hydroxy-9-(pyridine-4-yl)-6H-benzo[C]chromen-6-one]in(compound 2) were 26.6, 50 and 76.67% and 16.67, 36.67and 63.3% and 13.3, 23.3 and 36.6 % to 3rd, 5th instar larvae and adults, respectively. While in[ 3-thinyl-1-(2-hydroxynaphthyl) -1-propene] (compound 1), the mortality % were 23.3, 40 and 66.6% and 13.3, 30and 56.6% and 6.6, 16.6 and 26.6 % to 3rd, 5th instar larvae and adults, respectively. The results indicated that (comp.2) was the most toxic one and (comp.1) was the least toxic to confusedflour beetle when applied singly. The calculated LC50 values to (compound 2) were 0.019, 0.028 and 0.074 ppm to 3rd, 5th instar larvae and adults, respectively. While to (compound 1), the LC50 valueswere 0.025, 0.034 and 0.106 ppm to 3rd, 5th instar larvae and adults, respectively. The order of toxicity of the chemical compounds was 2 > 1. These chemical compounds can be used to control confused flour beetle