| Abstrakt: |
Water pollution has been increased by the discharge of several polycyclic aromatic hydrocarbons including Benzo (a) pyrene (BaP), which may affect aquatic animal lives and threaten human health. Common sole, Solea solea was selected as a bioindicator benthic fish to monitor pollution from El-Maadeya (one of the industrially polluted areas in Egypt). Concentration of "BaP" in collected samples of water, sediments and some organs of sole was detected using HPLC. A detected level of 21 μg ″BaP″/L was reported in water samples from El-Maadeya. Analysis results of ″BaP″ in El-Maadeya water, sediment, and biota exceeded the permissible limits. In a new trial for water remediation from ″BaP″, chitosan (Cs) was experimentally applied. Moreover, the impact of ″BaP″ alone or in combination with Cs for two weeks on water quality, sole fish brooders and histopathological changes in their ovaries was studied. Fifteen fish/tank were randomly classified into five groups in triplicates exposed to: GI) sea water only, GII) sea water with "DMSO", GIII) 21 μg ″BaP″/L (equivalent to the level detected in El-Maadeya), GIV) 50 μg ″BaP″/L, GVa) 21 μg ″BaP″/L & 0.5 g ″Cs″/L for 24 hrs and GVb) 21 μg ″BaP″/L & 0.5 g ″Cs″/L for one week. Obtained results showed that ″BaP″ accumulated in the liver and ovary of fish resulting in a negative impact on the reproduction due to the alteration of the ovarian architecture, atresia, and gonadosomatic index. Western Blot analysis showed also that ″BaP″ disrupted steroidogenic enzymes, upregulated the expression of Hsp-70, and forced the degradation of ERα. The addition of 0.5 g Cs/L has showed its efficiency against BaP toxicity, since it plays a role in ″BaP″ elimination by fast adsorption from water and sediments in timedependent manner, improved fish health, restored reproductive characteristics, decreased the percentage of atretic oocytes and reduced fish mortality. [ABSTRACT FROM AUTHOR] |
