Search

This study aims to monitor physico-chemical parameters and heavy metal (HM) levels in the water, HM levels, and haemato-biochemical changes in parasite-infected and non-infected catfish, Clarias gariepinus, in wild and cultivated origins. The outcomes of physico-chemical properties and heavy metal (HM) levels in water revealed significant variations between the two selected sites, except for cadmium metal (p< 0.05). HM concentrations in both water and organs of the two catfish origins decreased as the following decreased: Fe < Zn < Pb < Cu < As < Cd. Furthermore, the concentration of vital HM was significantly lower in wild catfish as compared to cultivated catfish, whereas non-vital HM was significantly higher in wild catfish. However, the HM accumulation in the different organs of catfish is ranked in ascending order: liver > gills > intestine > muscles. The hematological and biochemical investigations revealed a significant decline in the hemoglobin value, packed cell volume, number of red blood cells, albumin, total protein, and globulin while total aspartate aminotransferase activity, white blood cell count, alanine aminotransferase activity, glucose, and urea levels were all significantly higher in parasitic-infected catfish from two origins compared to uninfected catfish. Human health hazards, as evaluated by non-carcinogenic risk (hazard index and target hazard quotient), estimated daily intake, and carcinogenic risk, were all below the benchmark's allowable range. Nonetheless, the outcome of the health risk assessment suggests that consumption of the muscles of catfish from wild and cultivated origins cannot pose considerable health risks for children and adult consumers. Additionally, the prevalence of parasites can be used as a surrogate indicator to predict the possible impact of metal pollution and bioaccumulation. Consequently, this study suggests that Egypt's environmental management conducts routine HM monitoring in the studied sites to reduce potential health risks. [ABSTRACT FROM AUTHOR]

Over the last three decades, the Egyptian Red Sea shorelines had seen significant growth. In this short period, the Gulf of Aqaba's coastline has been turned into a lengthy belt of tourism settlements and hotels. Due to scarcity of information about this area, herein, a first-time ultimate remote sensing time-series change detection in the region. Landsat satellite data collected over the Gulf of Aqaba during the period from 1985 to 2020 and analysed to estimate urban expansion and shoreline changes in the study area, in addition, from 1995 to 2020 to monitor changes in the coral reef and benthic habitats coverage over time. Landsat 5-TM, Landsat 7-ETM+, and Landsat 8-OLI imagery were used to create a time series of satellite observations. The results showed that the urban development had a large scale increase in the past three decades by about 4.1 km2 and 2.8 km2 at Dahab and Nuweiba'a sectors respectively. While shoreline changed on a smaller scale than the urban development in a regular way without harm to natural resources. Changing - urban and shoreline - came along with tourism intensity. Concerning key environmental factors results of Time Series Analyses showed high variance in time especially during the period from 1993 to 2003, while the sea surface temperature had a stable trend. Benthic habitat mapping at Dahab showed stability of the coverage area of the most benthic habitats except for an increase of both corals and macroalgae between 1995 and 2005, whereas there is a fluctuation in coral coverage at Nuweiba'a area over time. [ABSTRACT FROM AUTHOR]