Environmental Distribution and Human Health Risks of Heavy Metals in the River Jhelum, Kashmir Himalaya.

This study investigates the spatial and seasonal distribution of heavy metals in the River Jhelum, evaluates potential contamination sources inferred from spatial trends and metal associations, and assesses the associated human health risks arising from heavy metal contamination in the River Jhelum. Water, sediment, and fish (Schizothorax niger and Cyprinus carpio) samples were collected seasonally from six sites representing upstream, midstream, and downstream gradients. Metal concentrations exhibited a significant downstream increase, with peak levels at Qamarwari due to urban and sewage inputs. Seasonal variation showed higher concentrations during autumn and winter, attributed to reduced dilution. Sediments acted as major sinks, while Cyprinus carpio showed higher bioaccumulation, particularly in liver tissues. Although metal levels in edible muscle tissue remained within permissible limits, transfer factor and health risk indices indicate potential long-term risks. The study highlights pollution hotspots and emphasizes the need for continuous monitoring and improved wastewater management in this fragile Himalayan ecosystem.