Metals concentrations and ecological risk assessments of fish farms sediments in Kafr El-Shaikh, Egypt.

Shaaban, Nashwa A.; Tawfik, Samar; Ali, Tamer El-Sayed

As a result of the freshwater sacristy and growing demands for fish production, the usage of fresh Nile water (Ri-W) for fish cultivation has been banned and replaced by the usage of agricultural drainage water (ADW). The agricultural drains collect wastewater from various sources that pose a potential for metal pollution. Subsequently, affect the quality of water and sediments of the receiving fish farm and poses health hazards to cultured fish and man. Farms' sediments act as a reservoir for metals and an internal source of metal. Thus, the evaluation of its metal contents and their indications are preferred for tilapia culture management. The present study investigates the levels of 7 metals (essential, and non-essential) in the surficial sediments of three fish farms irrigated with two different water sources (RiW, and ADW). Followed by an evaluation of sediment pollution and potential ecological risks using pollution indices (PI) and sediment quality guidelines (SQGs). The results indicated that the mean levels of the metals at the three fish farms follow the decreasing order of Fe (> 50,000 ppm) > Mn (700 ppm) > Zn (110 ppm) > Cr (75 ppm) > Cu (55 ppm) > Cd = Pb (not detected). According to PI, all metals were depleted to mineral levels (enrichment factor (EF) < 2 and showed unpo uted status and a most at ase ine eve s 1) relative to geoaccumulation index (I geo), contamination factor (CF), and pollution loading index (PLI). According to ecological risks, the adverse effects due to Zn and Mn were unlikely to be noticed, in contrast, a slight risk may occur due to Cu, and Cr. There were no restrictions on using ADW for fish cultivation, where sediments were not considered a source of secondary metal pollution. Continuous monitoring and evaluation of the pollution status of farm sediments are recommended.

EGYPT; ECOLOGICAL risk assessment; FISH farming; SEDIMENTS; WATER quality; SCRAP metals; METALS; HEAVY metals; TRACE elements in water

Egyptian Journal of Aquatic Biology & Fisheries, 2022, Vol 26, Issue 4, p377

1110-6131

Academic Journal

10.21608/ejabf.2022.250750