Effect of heavy metals in fish reproduction: A review

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.

Section: Developmental Effects Of Cadmium On Freshwater Fishmentioning

confidence: 99%

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

Vinanthi Rajalakshmi,

Liu,

Balamuralikrishnan

et al. 2023

“…Moreover, metals can induce morphological changes in tissues, such as gill damage and liver abnormalities, while also interfering with cellular functions, including enzyme activity and gene expression [22]. Several other studies have indicated that fish exposed to metals experience a decline in various reproductive parameters, including the gonadosomatic index (GSI), fecundity, hatching rate, fertilization success, abnormal shape of reproductive organs, and ultimately reproductive failure [23][24][25]. Moreover, various fish species can serve as effective biological indicators for assessing the extent of exposure to metals and other pollutants [15,16].…”

Section: Effect Of Metals On Fish Due To Exposurementioning

confidence: 99%

Bioaccumulation of Metals in Some Fish Species from the Romanian Danube River: A Review

Cordeli (Săvescu),

Oprea,

Crețu

et al. 2023

The Danube is the second-largest river in Europe and has been subject to pollution in the past. Additionally, in the last few years, the rapid pace of industrialization and urbanization has led to the inevitable pollution of this aquatic ecosystem by certain metals (essential and non-essential elements). This issue is considered the central problem of pollution in the Danube and is gaining increasing attention. Fish is a good source of proteins, polyunsaturated fatty acids (especially omega-3 fatty acids), essential vitamins, and minerals. Fish are often exposed to metals present in their aquatic environment through direct contact with contaminated water or by consuming organisms that have accumulated metals in their tissues; therefore, the elevated concentrations of metals in water and sediments are reflected in the fish flesh. In this context, the safety of fish and fishery products for human consumption is a public health concern. In the last two decades, more and more reports have shown that Danube River fish are contaminated with metals, causing great concern among consumers. The negative perception continues, although recent scientific studies show that metal levels in the edible parts of the fish are below acceptable limits. The objective of this study was to put together a multitude of scientific research studies that investigate the levels of some metals in various tissues of some fish species with high economic value in the Romanian market, as well as the levels of metals in the water and sediments. The collected data were then utilized to assess the potential health risks posed to humans.

“…In the soil, mercury has a long retention time; once accumulated, it continues to be released into surface waters and other environments for prolonged periods [2]. The contamination of the aquatic environment with heavy Fishes 2023, 8, 445 2 of 13 metals threatens the recruitment and survival of aquatic fauna due to detrimental effects on metabolism, growth, and reproduction [3][4][5][6][7].…”

Section: Introductionmentioning

confidence: 99%

Effect of Inorganic Mercury on Semen Quality, Embryo and Larval Development of Bocachico Prochilodus magdalenae

Madariaga-Mendoza,

Marrugo-Negrete,

Atencio-García

2023

The study aimed to evaluate the effect of inorganic mercury (iHg) on the sperm quality, embryos, and larvae of Prochilodus magdalenae. Two experiments were carried out. In experiment 1, semen was activated with contaminated water at different iHg concentrations (0.0, 25, 50, 100 µg/L) and sperm kinetics were analyzed with a computer-assisted semen analysis (CASA) system. In the second trial, 2 g of oocytes were fertilized with 50 µL of milt, activated with contaminated water at different iHg concentrations (0.0, 25, 50, 100 µg/L), and maintained that way during the first hour of incubation. Samples were taken every 3–4 h until hatching to identify embryo deformations. Fertilization and hatching rates were estimated. The survival of newly hatched larvae (1 day) and larvae eight days post-hatching (dph) was also assessed. The results show that the quality parameters of semen treated with contaminated water at different iHg concentrations (25, 50, 100 µg/L) were altered and showed significant differences (p < 0.05) from the control group (0 µg/L). Total motility decreased (9.8–13.2%) and the amount of immotile sperm increased (3-fold) relative to values in the control group. A significant increase in oocyte diameter and a decrease in fertilization and hatching rates were observed with the higher iHg concentrations (50–100 µg/L). Embryo deformations (>40%) such as scoliosis, lordosis, and microcephaly were observed, as well as premature hatchings. The larval survival at 1 dph was reduced between 25% (25 µg/L) and 97.2% (100 µg/L) relative to that in the control group. The results suggest that bocachico semen, embryos, and larvae are sensitive to contamination with iHg from 25 µg/L.