Beneficial role of ascorbic and folic acids antioxidants against thyroxin-induced testicular dysfunction in hyperthyroid rats

Environmental Science and Pollution Research - Thyroid hormones play a fundamental role in the regulation of metabolism of almost all mammalian tissue including the reproductive system....     

Contents of heavy metals in marine seaweeds from the Egyptian coast of the Red Sea

Seaweeds belonging to 14 different genera of Chlorophyta, Phaeophyta, and Rhodophyta were analysed to determine the levels of heavy metals in two areas of the Egyptian Red Sea coast. Among the trace metals analysed, Mn and Zn showed the highest mass concentrations in the surface sea waters of the two studied areas. However, algae obtained from the Suez area had higher concentrations of the investigated heavy metals than those collect in the Mars Alam area. Nevertheless, a high variability of the metal levels occurs among the studied algae and also between the investigated areas. Moreover, Zn was the most abundant metal in the seaweeds of the Suez area, while Pb was predominant in the Mars Alam area in red and brown algae. Liagora spp. had the highest average concentration factor of Zn in Suez (29 161-fold), while the average concentration factor in Enteromorpha spp. at Mars Alam was 20 091-fold. The highest Metal Pollution Index (MPI) value was recorded in Liagora spp. (22.0) at Suez. This represents a 4.6-fold higher value than that recorded in Liagora spp. at Mars Alam. Among green, brown, and red algae in Suez, the highest values of MPI were recorded in Cladophora spp. and Halimeda spp. (18.2 and 18.3), Padina spp. (16.2), and Liagora spp. (22.1), respectively; while at Mars Alam, the highest values of MPI were recorded in Cladophora spp. (6.6), Padina spp. (3.4) and Liagora spp. (4.8), respectively.     

Lead Speciation in the Sediments of the Heavily Polluted Western Harbor of Alexandria

The Western Harbor (WH) became under stress in the past decades, following successive increase in population. This study deals with local distribution of total lead and its species in the WH sediments. The lead content was high and there was a relationship between its enrichment and oil dispersed from ships. The lowest total lead value was found in the harbor middle far from direct effects of pollution. A five-step sequential extraction scheme was applied to illustrate the contribution shared by each individual fraction in the total lead concentration in the WH sediments. The exchangeable fraction (F1) was very low. The bound to carbonate fraction (F2), the bound to iron-manganese oxide fraction (F3) and the bound to organic matter—sulfide fraction (F4) ranked fourth, second and third in abundance. Oxygen was the main factor controlling the value of F2. F3 gave a direct relationship with total lead. The high levels of F4 occurred at locations of low salinity and enriched with organic matter. The residual fraction (F5) dominated other lead species, reflecting the sediment composition and the amounts of discharged pollutants.     

Contents of heavy metals in marine algae from Egyptian Red Sea coast

Seaweeds belonging to 14 different genera of Chlorophyta, Phaeophyta and Rhodophyta were analyzed to determine the levels of heavy metals in two areas of the Egyptian Red Sea coast. Among the trace metals analyzed, Mn and Zn showed the highest mass concentrations in the surface seawaters of the two studied areas. However, algae obtained from Suez area had the highest concentrations of the investigated heavy metals than those collected from Mars Alam area. Nevertheless, a high variability of the metal levels occurs among the studied algae and also between the investigated areas. Moreover, Zn was the most abundant metal in the seaweeds of the Suez area, while Pb was predominant in Mars Alam area in red and brown algae. L. farinosa had the highest average concentration factor of Zn in Suez (29161 fold), while it was 20091 fold in E. intestinalis at Mars Alam. The highest value of metal pollution index (MPI) was recoded in L. farinosa (22.0) at Suez. It represents 4.6 fold of that value recorded in L. farinosa at Mars Alam. Among green, brown and red algae in Suez, the highest values of MPI were recorded in Cladophora (mixed sub-species) and H. comuto (18.2 and 18.3), P. pavonia (16.2) and L. farinosa (22.1), respectively; while at Mars Alam, they were recorded in Cladophora (mixed sub-species) (6.6), P. pavonia (3.4) and L. farinosa (4.8), respectively.