The present study was carried out to envisage the impact of heavy metal . arsenic on the gut bacterial population of epigeic earthworm species, E. eugeniae. For this purpose, three different doses (, and w/v) of sodium arsenate (Na2HAsO47H2O) were used to treat adult earthworms. | Study to enumerate the alterations in gut bacterial population of eudrilus eugeniae exposed to sodium arsenate