Cadmium as an Endocrine Disruptor That Hinders the Reproductive and Developmental Pathways in Freshwater Fish: A Review

Abstract

Cadmium (Cd) is a non-essential element with sub-lethal effects even at low concentrations. The persistent nature of Cd and its tendency to bioaccumulate eventually create harmful effects on water biota, including fish. Cd affects various aspects of hormonal action in fish since it bioaccumulates in the endocrine system and hinders the synthesis, secretion, and metabolic activity of hormones, causing severe damage along the hypothalamus–pituitary–gonadal axis. Linking reproductive and developmental impairments in fish with ecologically relevant concentrations of individual metals can be challenging due to the complexity of aquatic ecosystems. This review deliberated the significant and novel trends of toxicological difficulties and approaches, including elucidating environmental sources’ bioavailability and Cd-induced toxic effects in freshwater fish. Both acute and chronic exposure to Cd can cause a range of adverse effects, such as growth inhibition, impaired reproductive capacity, endocrine disruption, and developmental abnormalities in freshwater fish, as evidenced by the present review. These investigations support the concept of Cd as a naturally available pollutant that causes irreversible damage in fish. These findings will help to understand the etiology of environmental circumstances that pose substantial dangers to fish health and are also crucial for preventing and treating exposure-related reproductive disturbances in freshwater fish due to environmental pollution.

Keywords

• cadmium
• endocrine disruptor
• freshwater fish
• metallothionein
• HPG axis
• reproductive and developmental impairments