Marble industry effluents cause an increased bioaccumulation of heavy metals in Mahaseer (Tor putitora) in Barandu River, district Buner, Pakistan.

The present study was conducted to evaluate the impact of marble industry effluents on the accumulation of heavy metals in selected tissues of mahaseer (Tor putitora) in Barandu River. Fish samples were collected from three selected sites (upstream (US), effluents/industrial (IS), and downstream (DS) sites) on monthly basis for 8 months. Heavy metal concentrations were determined in fish tissues using Atomic Absorption Spectrophotometer. Liver accumulated the highest level of metal concentrations while the lowest concentrations were found in muscles in T. putitora. Among metals, Fe was reported in the highest amount whereas the lowest was Cd in all the fish organs. In all the months, the metal concentrations were significantly higher (P < 0.05) at IS than the other two selected sites and also very often the metal concentrations at DS were found significantly higher (P < 0.05) compared to the US. The obtained results revealed that discharging industrial effluents caused an increased accumulation of heavy metals in fish tissues at IS compared to US and DS. Furthermore, in many cases, the concentrations at DS were also found significantly higher (P < 0.05) compared to US. It is further confirmed by skewness z-score which was found to be higher than 1.96 suggesting the hazardous effects of marble industries on the collective health of the river. It is therefore recommended that all these industries either should be moved away from the bank of River Barandu or must be bound to properly treat their effluents prior to discharge into the river in order to protect the biota of River Barandu from the pollution caused by these marble industries.