Marine pollution caused by heavy metals has emerged as a significant environmental concern, garnering increased attention in recent years. The accumulation of heavy metals in the tissues of marine organisms poses substantial threats to both marine ecosystems and human populations that rely on seafood as a primary food source. Fish and crustaceans are effective biomonitors for assessing heavy metal contamination in aquatic environments. In this study, we determined the concentrations of several heavy metals, including cadmium (Cd), lead (Pb), nickel (Ni), mercury (Hg), and tin (Sn), in four fish species (Mugil cephalus, Mugil capito, L. aurata, and Morone labrax) and five crustacean species (S. rivulatus, Cerastoderma glaucum, Paratapes undulatus, R. decussatus, Callinectes sapidus, and Metapenaeus Stebbingi) from Temsah Lake during both winter and summer seasons. To evaluate the potential ecological and health risks associated with consuming these fish and crustacean species, we calculated the metal pollution index (MPI), weekly intake (EWI), target hazard quotient (THQ), and carcinogenic risk (CR) values. The results revealed a noticeable increase in metal levels during the summer compared to winter in the studied samples. Moreover, the concentration of heavy metals in the muscles of the species generally exceeded those in the liver and gills. The MPI values indicated that Morone labrax exhibited the highest values during winter, while L. aurata showed the highest values during summer. Mugil cephalus demonstrated the lowest MPI values in both seasons. The EWI values for the studied metals were found to be lower than the corresponding tolerable weekly intake (TWI) values. Additionally, under average exposure conditions, the THQ and HI data were generally below one for most study species in the area. The calculated CR values for investigated metals in the studied species indicated acceptable carcinogenic risk levels. Therefore, this suggests that consuming studied species within Temsah lake does not present any potential health hazards for consumers.

This study investigated seasonal variation, spatial distribution, sources, composition and potential ecological risks of 16 polycyclic aromatic hydrocarbons (PAHs) in Red Sea coastal water. Surface seawater samples were collected at fourteen different locations. The sum of 16 PAHs concentrations in Red Sea showed clear variation between seasons, ranged from 1.08–6.10, 0.79–50.86, 1.37–54.47 and 0.21–7.18 μg/L in summer, autumn, winter, and spring respectively. PAHs levels in Red Sea coastal waters were relatively high at certain sites during autumn and winter seasons. They could be classified as highly polluted by PAHs contaminants (>10 μg/L). According to the diagnostic ratios measured, the majority of PAHs in this study originated from pyrogenic sources, while minor amounts originated from petrogenic sources. Four rings PAHs accounted for more than 64% of the total PAHs studied. PAHs pose a high ecological risk along the period of study, according to the ecological risk assessment by Risk quotients (RQNCs and RQMPCs).

This work investigates the prospective usage of dried date palm residues for eosin Y and eosin B (ES-Y and ES-B) dye removal from an aqueous solution. A green synthesis route is utilized to prepare carbon nanofibers (CNFs) from date palm residues. We study the characteristics of carbon nanomaterials based on their composition and morphology. The characterization includes different types of instruments such as a Fourier-Transform Infrared Spectroscopy (FTIR), Brunauer Emmett Teller (BET), and Scanning Electron Microscopy (SEM). Batch mode experimentations are conducted and studied utilizing various significant factors such as the dose of the adsorbent, solution pH, contact time, and the initial quantity of eosin molecules as a pollutant. The dye adsorption capability improves with an increasing adsorbent dose of up to 40 mg of CNFs. The adsorption of dyes onto CNFs achieves equilibrium in around 60 h, whereas the optimal starting dye concentration in this study is 50 ppm. Further, to study the under-investigated toxic molecules’ adsorption process mechanism on the nanomaterials’ active sites, we introduce kinetic models involving pseudo-first-order, pseudo-second-order, and models based on intra-particle diffusion. Langmuir and Freundlich’s isotherms are considered to study the equilibrium isotherms, and the Langmuir isotherm model deals considerably with the attained experimentation results.

Acid volatile sulfide (AVS) has been proposed as a possible indicator of metal toxicity since it can effectively react with metals and make them unavailable to biota.[1] Several divalent transition...