Histological Biomarkers in Fish as a Tool in Ecological Risk Assessment and Monitoring Programs: A Review

Abstract

Abstract. Water contamination, both in freshwater and marine ecosystems, has been a serious environmental problem all over the world in the last few decades. One of the most common anthropogenic pollutants, which enter the water bodies are metals and metalloids with no biological functions (As, Cd, Hg, Ni and Pb), pesticides and other persistent organic pollutants such as PAHs, PCBs, tributil tins, dioxins, etc. Most of these pollutants tend to accumulate in biota, biomagnify in the food chains and they are also difficult to break down to less harmful substances. In order to better understand the negative effects on living organisms, and particularly fish, biomarkers at different levels (cell, tissue, organism and population) are applied. In addition, the biomarkers at tissue level such as histological alterations in different fish organs give valuable information about the xenobiotic impact. Thus, they are recommended as useful biomarkers in eco-toxicological research, risk assessment and monitoring programs. In the present paper we aimed to review the use of histological alterations in fish organs such as gills, liver and kidney in ecotoxicological studies, based on collected scientific data from the late 1960's until today.

Toxicity and bioaccumulation of Cadmium, Copper and Zinc in a direct comparison at equitoxic concentrations in common carp (Cyprinus carpio) juveniles

“…Exposure of freshwater fish to elevated metal levels in the aquatic environment, and the subsequent disturbance in iono- and osmoregulatory processes, typically results in morphological changes of their branchial apparatus (Fonseca et al 2016; Yancheva et al 2016). Due to the high plasticity of gill tissue, abovementioned physiological mechanisms can induce tissue damage and/or remodeling.…”

Kidney morphology and candidate gene expression shows plasticity in sticklebacks adapted to divergent osmotic environments

“…Given the species' capacity to acclimatize and adapt to a wide range of salinities -its distribution extends throughout coastal marine and lowland freshwaters of the boreal and temperate northern hemisphere (Bell and Foster, 1994) -it is an ideal model for studies of kidney structure and function. Whilst the kidney has been the target of many physiological studies aimed at understanding the mechanisms of ion transport in various species of marine and freshwater fishes (Yancheva et al, 2016), it has received considerably less attention in sticklebacks. Earlier comparative studies revealed that the renal structures of freshwater sticklebacks are better developed than those from the marine environment (Ogawa, 1968;Wendelaar Bonga, 1973).…”

Toxic effects of copper sulphate pentahydrate on antioxidant enzyme activities and lipid peroxidation of freshwater fish Capoeta umbla (Heckel, 1843) tissues

“…In fish as in higher vertebrates, the kidney performs an important function related to electrolyte and water balance and the maintenance of a stable internal environment. Following exposure of fish to toxic agents such pesticides, histological alterations in the fish kidney were found at the level of the tubular epithelium and glomerulus (Yancheva et al, 2016).…”