Ecotoxicological effects of anthropogenic pressure in semi-enclosed artificial lagoon ecosystems in the Gulf of Aqaba

Heavy metals are considered to be among the most potent environmental contaminants, and their release into the environment is increasing rapidly since the last decades from various sources and activities and may enter into the environment by a wide range of pathways and processes. They can be translocated, disperse in the environment, and bio-concentrate in aquatic organisms, causing increase ecosystem degradation and leading to biodiversity loss. Furthermore, they may enter the food chain, creating health risks for both humans and animals. This study aimed to evaluate the ecotoxicological effects of anthropogenic pressure in semi-enclosed artificial lagoon ecosystems in the Gulf of Aqaba, Red Sea. Our findings with regard to heavy metal contamination showed that the area is contaminated by significant amounts of several potentially toxic heavy metals (such as Cd, Cr, Cu, and Fe). The anthropic intervention in the area impacted heavily the natural environment. We found that the biological test (lipid peroxidation) was a useful assay for assessing the overall health condition and response (stress level) towards natural and anthropogenic forces in the studied areas. The selected marine organisms (Holothuria atra, Tripneustes gratilla, Ulva lactuca and Halophila stipulacea) have the ability to accumulate several levels of heavy metals in their tissue with different trends of bioaccumulation. Therefore, they can be used as promising bioindicators for such research. The results obtained permit to assess the environmental effects of anthropogenic pressure and can be a useful basis for planning possible remediation projects.