Bardawil Lake is a unique aquatic ecosystem that provides a habitat for various fish and other marine organisms. This study aimed to analyze the quality of fish species to prove that this lake is free of pollution, not other Egyptian lakes, due to the accumulation of some heavy metals (Cd, Pb, Cu, and Zn) in various tissues of fish species that were caught from this lake. Thirty-five fish samples were caught during the Spring of 2018 from seven different species: Mugil cephalus, Liza auratus, Sparus aurata, Dicentrarchus labrax, Siganus rivulatus, Anguilla angilla, and Solae solea. The Association of Official Analytical Chemists methods using a spectrophotometer determined the biochemical composition. In contrast, atomic absorption spectrometry (AAS) was employed to determine the heavy metals expressed by µg/g wet weight. Results exposed that the accumulation of essential micronutrient (Cu, Zn) content was higher than toxic elements (Cd & Pb) in muscles in order to Zn > Cu > Pb > Cd. Muscles < gills < liver in order of all metals except Pb with order muscles < liver < gills. The metals studied in the muscles were lower than those set by the WHO and the EU standards. The carcinogenic risk with lower allowable limits of 1 × 10^–6 to 1 × 10^–4 in both normal and high consumption groups; target and total target hazard quotients (THQ & HI) in muscles were < 1. The biochemical composition level was highest in the liver, except for protein, which was highest in muscle for all fish species. There is no evidence of harmful contaminants in the muscular tissue of the fish sampled from Bardawil Lake, although fishing activity. However, customers should know that health concerns may be associated with overeating fish.

This study aimed to assess the influence of pollution on the quality of sediments and the risks associated with El-Qusier and Safaga Cities, Red Sea, Egypt, during 2021, divided into four sectors, using multiple pollution indices. To achieve that, we evaluated the metal pollution index (MPI), contamination factor (Cf), pollution load index (PLI), contamination security index (CSI), and anthropogenicity (Anp%). Moreover, carcinogenic and non-carcinogenic risks are used for human health hazards. Results indicated that Mn and Fe recorded the highest concentrations, whereas Cd had the lowest. El-Quseir City sediments were found the following metal ions: Fe > Mn > Ni > Zn > Cu > Co > Pb > Cd, where the order in the Safaga City was: Fe > Mn > Zn > Ni > Cu > Pb > Co > Cd. MPI > 1, this is alarming in the study area due to heavy metal pollution. In addition, C_f < 1 in all metals except Cd with contamination degree CD ranged from low to considerable contamination in El-Qusier city. In contrast, contamination ranged from significant to very high in Safaga city. PLI < 1 is lower than the reference at all monitored stations. CSI values ranged from relatively low to moderate. Besides Cd, data reflect each element's low environmental danger (Eri^Me40). This study's risk index (RI) is low to moderate in Sector 1 and high to extremely high in Sector 2. HQ and HI index < 1 means it is safe for human health in order: HI _ingestion > HI _dermal. CSR for different pathways was recorded as dermal > ingestion, in which total CSR for all paths is considered harmful, and the cancer risk is troublesome and higher than the reference ranges of 1 × 10^–6–1 × 10^–4. In conclusion, the examined heavy metals provide environmental hazards across the assessed locations.

The Red Sea’s near-shore zones are considered nurseries and grazing grounds for the various economic fish species. To illustrate the relation between human health and seafloor sediments, the geological and geochemical properties of seafloor sediments were investigated in near-shore zones at Marsa Alam and Hurghada cities along the Red Sea. The obtained data illustrated that the sediment nature at Hurghada is primarily of biogenic origin, as indicated by the high carbonate contents; however, the sediment nature at Marsa Alam is attributed mainly to the terrigenous origin. Accordingly, the studied heavy metals at both localities showed different feeding sources; Marsa Alam sites showed high levels of Fe, Mn, Zn, Ni, and Cu attributed to terrigenous inputs; however, the high averages of Cd and Pb at Hurghada indicating influence from land-based and anthropogenic activities. The calculated risk assessment parameters and carcinogenic risk (ILCR) do not indicate any significant risk. Geochemically and as indicated by the statistical parameters: correlation coefficient, PCA, and Geo-accumulation (Igeo); Mn, Zn, Cu, and Ni were found to be mainly associated with Fe in the same source of accumulation and similar geochemical forms. However, the adsorption over sediment particles and/or assimilation inside the carbonate lattices are possible occurrences of Cd, Pb, and partially Ni. The calculated risk assessment parameters and carcinogenic risk (ILCR) do not indicate any significant risk to marine organisms and human consumption.