Even though there are strict governmental policies regarding the establishment of mulberry plantations near industry processes and irrigating plantations with the wastes from these industrial processes, most rural industrial sources and farmers in China but more particularly in India evade the policies. Due to these industry processes, large quantities of micro-pollutants such as chromium, cobalt and nickel are discharged into the environment and can ultimately have significant adverse biological and ecological effects on the leaves of mulberry plantations that are fed to silkworms. This research was carried out in an effort to study the hazard assessment of a micro- pollutant on two mulberry silkworm races. From the results obtained it was revealed that both silkworm races were susceptible to the form and quantity of chromium species used. The mean susceptibility index of -16.77 and ?2.61 for Qiufeng X Baiyu and Qingsong X Haoyue respectively showed that both silkworm larvae were more susceptible to Cr (VI) ions than Cr (III) ions. Cr (III) species reported values of ?0.56 and ?.14 for Qiufeng XBaiyu and Qingsong X Haoyue respectively. Based on growth and development of both silkworm races, the influence of form and quantity of chromium species on the RGR, RG1 and death rate indicated that larvae development was slower and mortality was higher as the concentration of Cr(III) and Cr (VI) ions increased. Even at low concentrations of 400mg/L of Cr (III) and 400mg/L of Cr (VI) ions in the diet, both species significantly depressed growth. Reduced RGR values of 14% and 21% was reported for Qiufeng X Baiyu and Qingsong X Haoyue respectively when 800mg/L of Cr (III) was applied. Depression in the RG1 with increasing concentration indicated that the form and quantity of chromium ions acted as growth inhibition in both silkworm races. Through linear regression analysis, the EC5(, (concentration of the compound that caused 50% reduction was in terpolated for both tested compounds. EQ0 (mg/L) of Cr (III) ions for Qiufeng >< Baiyu and Qingsong / Haoyue was 800 and 600 respectively. EC50(mg/L) of Cr (VI) ions for Qiufeng / Baiyu and Qingsong / Haoyue was 600 and 316 respectively. VI Blood catalase activity of 5th instar larvae of chromium poisoned Qiufeng X Baiyu larvae showed that day 6 had the highest blood catalase activity of 2.729, 2.940 and 3.014 mg.min~, mL?for control, Cr (III) and Cr (VI) species respectively. Qingsong>( Haoyue larvae also had the highest blood calatase activity on day 6 with 2.899, 3.746 and 3.907mg.rnin? m[?for control, Cr (III) and Cr (VI) respectively. Significant differences were observed in cocoon shell rates for both species irrespective of the tiom and quantity of Cr ions used. The control groups of both races gave higher cocoon shell rate of2l.08% and 21.07% for Qiufeng X Baiyu and Qingsong X Haoyue respectively. 800mg/L of Cr (VI) ions drastically reduced the cocoon shell rate in both silkworm races. 11.13% and 9.01% of cocoon shell rate was reported for Qiufeng)< Baiyu and Qingsong X Haoyue respectively. No significant differences were observed between fresh silk gland weights as well as fatbody weight for both silkworm races at p ~0.05 Turkey抯 HSD test. However standard error bars delineate observable differences in silkgland and fatbody weights of both races. QiufengXBaiyu had the highest silkgland and fatbody weights of 134.04 and 36.12mg respectviely. QingsongXHaoyue had