Seasonal Variations of Polycyclic Aromatic Hydrocarbons in the Muscle Tissue of Silurus triostegus Heckel, 1843 from Derbendikhan Reservoir

Abstract

Derbendikhan reservoir is located on the southeast of Sulaimani city 35° 6' 35" N, 45° 41' 20" E, it is the second largest reservoir in the Iraqi Kurdistan region at an altitude of 485 m above sea level. It was formed when the dam was constructed in1956–1961. The area is about 114.30 km2 with the maximum depth of 75.0 m. Silurus triostegus is one of twenty genera of fish that are endemic to Derbendikhan reservoir, Seasonal sampling for 64 samples of fish for 11 sites was carried out from November 2018 to August 2019, Fishing was performed with gill nets of 18, 25, 33, 40, and 55 mm inner mesh sizes. The goal of this research is to determine the level of PAHs in, fish muscle of Silurus triostegus, because fish as an important food source for man and it’s the primary indicator of the toxification of streams and lakes, on the other hand, PAH will cause many health problems including cancer, in addition, this information may be used as a database for any environmental modeling in the future, this study was carried out. Results indicate increasing in PAH in the spring season, although, as a result of fishing activities using old boats and ships at a high rate, in addition to the changes of water temperature in different season. PAH in the muscle of fish (0.098–1.271 μg/g) were above the WHO maximum permissible limit of 0.001 μg/g. The main conclusion is that the fish muscle contains high amounts of PAHs through bioaccumulation and biomagnifications. Finally, the lake needs immediate attention to reduce improper waste disposal and improve on measures against indiscriminate dumping of petroleum products and domestic waste in the water, which are the major sources of petrogenic and pyrogenic PAHs should be minimized, and the treatment of the sewage before its discharge into the reservoir.