alkylphenol polyethoxylates is a group of estrogenic compounds. natural or synthetic types of these compounds react with the endocrine system by binding hormone receptors, resulting in interference with their action, which is why they are called endocrine disrupting chemicals. among their hydrolytic products are nonylphenols (np), which are considered pollutants of aquatic environments. the objective of this study was to evaluate the pathological alterations on liver tissue of fish exposed to these compounds for long durations, starting from beginning of life and during the period of sexual maturity. tilapia fish were obtained from abhur fish farms, reared in the laboratory in special basins, and divided into two groups. the first maternal group was untreated and their larvae were divided into three sub-groups: control; exposed to 15μg/l; and exposed to 30 μg/l. the second maternal group was divided into 2 sub-groups: with larvae exposed to 15μg/l; and with their larvae exposed to 30 μg/l. larvae and mother exposed to different concentrations of np (15 and 30 μg/l) showed an increased accumulation of np in both livers and muscles compared to the control group due to bioaccumulation. tissue section examinations of the treated group (15 μg np /l) showed disruption of liver architecture, with lyses, loss of nuclei, necrosis, and fatty infiltration. the changes were more marked in tissues exposed to (30 μg np /l). although this pollution was not lethal, its effect may be reflected in vital activities and in the economy.