The present study was performed to have knowledge of hydrocarbon compounds pollution status in the water (dissolved and particulate fractions), sediments, two species of aquatic plants (Ceratophyllum demersum and Paspalum pespaioides), two species of fishes (Liza abu and Carassius auratus) and one species of molluscs (Pseudodantopsis euphraticus). The samples were collected monthly for the period November 2012 to October 2013 from four different stations (Al-Magideh, Treatment unit, Al-Husaichi and Al-Zubair) distributed along Al-Kahlaa River in Missan province, in addition to Reference...