This study intends to quantify the tolerance of six bacterial strains to chromium (Cr⁶⁺) and cadmium (Cd²⁺) in three different soils (sandy loam, silt loam, silty clay loam). In this experiment, chromium and cadmium were selected as the heavy metals since these metals are generally discharged from industries like tannery, textiles, dying factories etc. in the city of Dhaka. The six bacterial strains, named as A1, A2, A3 were collected from agricultural soil and C1, C2, C3 were procured from industrial contaminated soil which were acquired from the stock of soil microbiology laboratory at University of Dhaka, and identified at molecular level by Tanu and Hoque (2013).Among the six bacterial strains, five samples were belonged to the Bacillus species; whereas, the remaining one fell into Micrococcus species. Three representative agricultural soil samples which were tested for heavy metal tolerance under different intervals of incubation, were collected from Dhamrai, Khustia and Gopalgonj. Bacterial tolerance to Cr⁶⁺ and Cd²⁺ in different soils exhibited different trends with varying incubation periods. Test results indicate that both Bacillus (A1), and Micrococcus(C3) showed the highest tolerance to heavy metals in silty clay loam soil.

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