Abstract The present study was aimed to assess physico-chemical parameters and heavy metals (HM) concentration in marble industrial effluents, and HM bioaccumulation in the workers’ blood employed in the marble industries in Mardan Industrial Estate (MIE) of district Mardan, Khyber Pakhtunkhwa (KP) province, Pakistan. A total of twelve samples were collected from industrial effluents and seven samples of blood were collected from healthy workers of different marble units on volunteer basis. Water samples were collected for analysis of physico-chemical parameters such as electrical conductivity (EC), pH, turbidity, sodium (Na), potassium (K), calcium, hardness, chloride, magnesium (Mg) and heavy metals, that is Copper (Cu), Manganese (Mn), Zinc (Zn) and Arsenic (As), and compared with the National Environmental Quality Standards (NEQS) of World Health Organization ( WHO, 2010 ). Blood samples from the marble industries workers were collected for the analysis of HM i.e. Cu, Mn, Zn and As bioaccumulation. Our results showed that most of the samples showed higher physico-chemical parameters with respect to the permissible limit set by the NEQS of WHO, 2010. Similarly, HM in water as well as in workers blood also revealed higher values than the permissible limit concentrations set by Occupational Health and Safety Act (OSHA), Occupational Health and Safety Division (OHSD) and Agency for Toxic substances and Disease Registry (ATSDR), USA. Therefore, the major findings of the study suggested that higher level of alteration in the physico-chemical parameters and HM in water and workers’ blood will have great impact on freshwater resources and human health in the study area. Therefore, it is highly recommended that wastewater treatment plant should be constructed in the MIE of district Mardan to treat polluted water discharged from the marble manufacturing units prior entering into freshwater courses in the study area. Moreover, an awareness program should be launched to aware the workers of marble manufacturing units, as well as local community, regarding water pollution and heavy metals bioaccumulation caused by marble production units, and its mitigation to protect themselves and aquatic wildlife from the devastating impacts of water pollution occurring in the study area.