Detection of the Cyanobacterial Neurotoxin β-N-methylamino-L-alanine (BMAA) in Water and Tilapia Fish of a Tropical Fishpond in Egypt

Mohamed, Zakaria A; Vasconcelos, Vitor; Badawye, Hanan

doi:10.21608/sjsci.2023.209977.1079

Detection of the Cyanobacterial Neurotoxin β-N-methylamino-L-alanine (BMAA) in Water and Tilapia Fish of a Tropical Fishpond in Egypt

Document Type : Regular Articles

Authors

¹ Department of Botany and Microbiology, Faculty of Science, Sohag University, Sohag 82524, Egypt.

² CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, Terminal de Cruzeiros Do Porto de Leixões, Av. General Norton de Matos, s/n, 4450-208 Matosinhos, Portugal

³ Department of Biology, Faculty of Sciences, University of Porto, Rua Do Campo Alegre, 4169-007 Porto, Portugal

10.21608/sjsci.2023.209977.1079

Abstract

β-N-Methylamino-L-alanine (BMAA) is a neurotoxic non-protein amino acid and causes neurodegenerative diseases. While the presence of BMAA toxin in phytoplankton communities and its bioaccumulation in aquatic food animals has been demonstrated worldwide, the detection of this toxin has not yet been explored in Egyptian freshwaters. Therefore, the present study determined BMAA levels in phytoplankton samples and edible muscles of tilapia fish sampled from an Egyptian fishpond. BMAA concentrations in phytoplankton samples were higher in summer (227.66 µg L^-1) than in winter (0.15μg L^-1), in association with the dominance of cyanobacteria in this fishpond. BMAA was detected in edible fish tissues at higher levels in summer (73.2 μg g^-1) than in winter (1.16 μg g^-1). Compared to the guideline values (GVs) derived during the present study (9.1 and 2.3 μg g^-1 for adults and children, respectively), BMAA levels detected in edible fish tissues during summer exceeded these GVs by a factor of 8 for adults and 32 for children, but it was below these limits in winter. This may represent a health risk to humans through fish consumption. Therefore, the study suggests monitoring toxic cyanobacteria and their cyanotoxins in fishponds and aquacultures. Additionally, fish edible tissues should be tested for cyanotoxins before marketing.

Keywords

Main Subjects