Modern Chemistry 2020; 8(3): 33-39 http://www.sciencepublishinggroup.com/j/mc doi: 10.11648/j.mc.20200803.11 ISSN: 2329-1818 (Print); ISSN: 2329-180X (Online) Effects of Heavy Metals Pollution on Some Fish and Mollusc Species from Port Sudan, Sudan Issra Mohammed Osman Mahjoub 1, * , Mohamed Elamin Hamza 2, 3 1 Department of Fisheries, College of Natural Resources and Environmental Studies, University of Bahri, Khartoum, Sudan 2 Department of Chemistry and Biology, Faculty of Science and Technology, Merowe University of Technology, Merowe, Sudan 3 Institute of Marine Research, Red Sea University, Port Sudan, Sudan Email address: * Corresponding author To cite this article: Issra Mohammed Osman Mahjoub, Mohamed Elamin Hamza. Effects of Heavy Metals Pollution on Some Fish and Mollusc Species from Port Sudan, Sudan. Modern Chemistry. Vol. 8, No. 3, 2020, pp. 33-39. doi: 10.11648/j.mc.20200803.11 Received: June 24, 2020; Accepted: November 4, 2020; Published: November 16, 2020 Abstract: The effects on fishes Lethrinus harak and Cephalopholis minata and on the mollusc Tridacna maxima exposed to different concentrations of heavy metals vanadium, nickel, and copper were investigated. The study indicated that the LC50 for nickel were 198.200 ppm, for L. harak, 196.041 ppm for C. minata and 198.200 ppm for T. maxima. The LC50 for copper were 197.175 ppm for L. harak, 272.932 ppm for C. minata and 272.841 ppm in T. maxima. However, LC50 for vanadium recorded 131.836 ppm for L. harak, 164.769 ppm for C. minata and 164.037 ppm for T. maxima. On the other hand, LT50 due to nickel exposure recorded 74.815, 47.963, and 95.116 hours, for L. harak, C. minata and T. maxima, respectively. LT50 due to copper recorded 35.041, 47.681, and 71.835 hours for L. harak, C. minata and T. maxima, respectively. However, LT50 for vanadium were 11.989, 47.511 and 5.792 hours for L. harak, C. minata and T. maxima, respectively. In this study no response was detected in lower concentrations of nickel and copper i.e. 4 ppm and 32 ppm, however a high response was detected with the same concentrations of vanadium. The study indicated that T. maxima, was more tolerant for heavy metals pollution than L. harak and C. minata. Nickel concentrations detected in tissues analysis were 0.561-0.04 ppm, 0.421-0.02 ppm and 0.871- 0.03 ppm for L. harak, C. minata and T. maxima, respectively. While copper concentrations recorded 1.1030-0.09 ppm, 0.4060-0.02 ppm and 1.35-0.03 ppm for L. harak, C. minata and T. maxima, respectively. However, vanadium concentrations, recorded 0.010-0.00 ppm, 0.04-0.014-0.01 ppm and 0.042-0.00 ppm for L. harak, C. minata, and T. maxima, respectively. Keywords: Heavy Metals, Fish, Mollusca, Pollution, Red Sea, Sudan 1. Introduction Marine pollution is a global environmental problem mostly attributed to human activities on land, water and air. Sediments and organisms releasing potentially toxic substances into the water also contribute to the level of contamination. Contaminants can stay in the water in dissolved form or they can be removed from the water column through sedimentation [1]. On the other hand oil pollution was dangerous from its discovery throughout stages of production, transportation, refining, processing, storage, marketing and even disposal of used products. This was resulted in bioaccumulation and physical contamination of beaches. The seas and oceans were polluted by millions of tons of oil annually since most of the factories and refineries were built along the coast [2]. In Japan, as a result of discharge of waste water containing mercury in Port Minamata bioaccumulation in tissues of marine organisms occurred and led to cases of poisoning in 1952 known as Minamata syndrome [3]. The marine biota and habitat of Port Sudan area were negatively affected by discharge of harmful substances into the marine environment or indirectly from land based activities [4]. However, assessment and effects of heavy metals pollution at the Sudanese Red Sea coast were also studied [5, 6]. Sudan has become an oil exporting country since 1999 and two ports (Bashayer I and Bashayer II) were constructed for oil export and import. Approximately 400,000 barrel were exported per day since the mid of 2006. However, few and