Characterization of major and trace elements in coastal sediments along the Egyptian Mediterranean Sea.

The present study was conducted to provide a comprehensive picture of marine sediment characterization in terms of geochemistry and the extent of pollution. A total of 99 surface coastal sediments were collected from coastal areas along with the Egyptian Mediterranean Sea. The samples were analyzed by neutron activation analysis (NAA) and the mass fractions in mg/kg of 39 trace elements were determined. The normalized mass fractions show significant amounts of Cl (26.4%), Sn (12%), Zr (7.3%), Hf (5.9%), Ti (4.7%), Cr (4.2%), Ca (3.4%), Si (3.1%), Sr (2.9%). The mass fractions of the rare earth elements REEs (La, Ce, Nd, Sm, Eu, Tb, Dy, Yb, and Lu) are almost double compared to literature data. Principal component analysis PCA and positive matrix factorization PMF were used to decipher the sources of pollutions. Sediment quality was quantified using different pollution indices such as enrichment factor (EF), modified pollution index (MPI), pollution load index (PLI) and the new approach to calculate total pollution index (TPI). The results of the study recognized four locations with significant pollution, namely the coastal area along Al Manzalah Lake, the Nile River estuaries at Ras Elbar and its western coastal area, at the outlet of Elbrullus Lake, and finally the Abu Qir Bay. The obtained result can serve as a geochemical background of the sediments of the study coastal area, which allows following the quality of marine sediments along with the Egyptian Mediterranean Sea.

Monitoring of air pollutants using plants and co-located soil-Egypt: characteristics, pollution, and toxicity impact.

The present work was conducted to evaluate the air quality in terms of inorganic pollutants and toxicity impact using two evergreen tree leaves, Eucalyptus globulus Labill (E. globulus) and Ficus microcarpa L.f., Suppl. Pl. 442 (1782) (F. microcarpa) as biomonitors. Thirty tree leaves and an equal number of co-located soil samples from different regions of Egypt (urban Greater Cairo Metropolitan (GC) and rural Menoufia Governorate (MG)) were collected. The concentrations of 34 and 40 elements were determined using instrumental neutron activation analysis (INNA) and atomic absorption spectrometry (AAS) in tree leaves and soils, respectively. Bivariate and multivariate statistical analyses were implemented. The air pollution was assessed using enrichment factor, pollution load index, potential ecological risk, and risk index. In addition, human and ecotoxicity were evaluated based on the ReCiPe method. The mean concentration values of the obtained elements in tree leave in urban Greater Cairo and rural Menoufia Governorate show that the major elements are slightly higher in F. microcarpa than in E. globulus. Likewise, the mean values of elements in soil from GC and MG show no significant difference except for major elements (Fe, Al, Mg, K, Na, and Ti) in MG. The normalized concentrations of tree leave and soil show that the accumulated elements by F. macrocarpa are slightly higher than in E. globulus in GC and MG. While in terms of the investigated area, the concentrations of elements in MG are considerably higher than in GC. Pollution load index (PLI) spatial distribution over investigated areas showed that despite high population density, heavy traffic, and urban pollution, the Cairo samples exhibit significantly lower values as compared to those from Menoufia, which is most likely due to the uncontrolled industrial and domestic waste disposal outside Cairo. Potential ecological risk (PER) was significant for As in soil and for As and Cd in tree species. Human toxicity shows higher values in urban locations. Contrariwise, in the terrestrial ecotoxicity aspect, the rural locations are much higher than in urban ones.

137Cs and K annual fluxes in a cropland and forest ecosystems twenty-four years after the Chernobyl accident.

Biological cycles of the Chernobyl originated cesium-137 (137Cs, radiocesium) and the natural potassium (K) in oak, birch, and pine forest, and wheat cropland in Russian Federation, approximately 500 km northeast of the Chernobyl Nuclear Power Plant, were subject to a multiyear monitoring. By 2010, the annual return of 137Cs from forest vegetation to the soil in dead tree components still exceeds its annual accumulation in the tree phytomass by a factor of 4-6, apparently due to residual surface contamination in the external bark and the ongoing process of tree stand decontamination following the initial fallout. In the cropland, both ascending and descending fluxes of 137Cs are close to the steady state. The annual accumulation of 137Cs in the tree biomass was the highest in the oak forest and the lowest in the pine forest. The annual K accumulation was the highest in the cropland and the lowest in the pine forest.