A systematic review on assessment of heavy metals toxicity in freshwater fish species: Current scenario and remedial approaches

Background: Heavy metal contamination poses a significant threat to freshwater ecosystems. This systematic review aimed to assess the current status and knowledge regarding heavy metal toxicity in freshwater fish species and remedial approaches for reducing its adverse effects. Methodology: Multiple scientific databases were screened to find peer-reviewed articles published between the years 2000 and 2023 that contained the topic of this study. Heavy metals, freshwater fish species, toxicity, and remedial measures were among the keywords and controlled vocabulary included in the search strategy. Results: As a result of this review 180 eligible studies were found suitable based on inclusion criteria in the systematic review. Maximum freshwater sources have been contaminated with heavy metals like "lead, mercury, arsenic, cadmium, fluoride" which harm freshwater fish species. Due to fish bio-cumulative power, some fish species accumulate higher heavy metal concentrations in their body tissues. Species in higher trophic levels accumulate the most heavy metals, posing a serious health risk to humans. The remedial approaches must be considered to mitigate the negative effects of these heavy metals. Various aquatic macrophytes plants are used for remediation purposes to remove heavy metals from aquatic sources as a green technology for remediation purposes to mitigate metal pollution. Conclusions: In this systematic review, heavy metal toxicity in freshwater fish species is discussed along with remediation approaches to reduce its impact on freshwater fish species. For the prevention of adverse effects on human health and aquatic ecosystems caused by heavy metal contamination, this contamination must be studied and monitored.