Keeping in view the industrial and domestic sewage containing untreated water direct discharge into River Chenab via Chakbandi main drain (CMD), the current research project was planned with the objectives to determine the effect of freshwater pollution on physicochemical parameters, heavy metal determination in the River Chenab water and its effects on fatty acids profile in four muscle zones (dorsal, ventral, ventricha and tail) of wild major carp (Labeo rohita). Fish species were collected from two different sites of River Chenab one as less polluted site (LPS-upstream to CMD) and other as highly polluted site (HPS-downstream to CMD) while control samples were collected from Fish Hatchery, Satiana Road, Faisalabad. Fatty acid (FAs) analysis was performed by Gas Chromatography using Flame Ionization detector. A total of 24 FAs were recorded in this Fatty acid profile/analysis. Out of 24 FAs; there were 7 saturated fatty acids (SFA), 6 monounsaturated fatty acids (MUFA) and 11 polyunsaturated fatty acids (PUFA) in fish muscle. The SFA contents were found at a highest (77.772±0.472%) in dry meat in ventral muscle zone of Labeo rohita harvested from a highly polluted site (downstream) of river Chenab. In contrast, SFA contents were found at a lowest ((26.026±0.033%)) in the dorsal muscle zone of Labeo rohita harvested from commercial fish farmed closely followed by tail muscle zone (26.917±0.030%)and clear difference from upstream and downstream wild fish. The maximum concentration of MUFA contents were found in ventral muscle zone (21.560±0.032%) of Labeo rohia collected from commercial fish farmed as compared to upstream and downstream area of River Chenab. While in the same case of PUFA contents were found at highest (42.140±0.016%) in the ventral muscle zone of Rohu harvested from commercial fish farmed. In contrast the concentration of PUFA profile were found lowest in all muscle zones of wild fish collected from  LPS and HPS of River CenabThere was a significant (P˂0.05) decrease in SFA composition of fish samples downstream of the river than farmed and upstream wild fish. . The fatty acids C8:0, C12:0, C20:0, C16:1(n-7), C16:1(n-9), C18:1(n-9), C20:1(n-9),C18:2(n-6), C22:4(n-6), C20:5(n-3) were not detected in all muscle zones of wild major carp Labeo rohita  collected from HPS of River Chenab.

 Keywords:

Labeo rohita, Water Pollution, Fatty Acids Profile, Saturated fatty acids, Polyunsaturated fatty acids, Monounsaturated fatty acids, Muscle zones