Bioaccumulation of Heavy Metals in Water, Sediments, and Tissues and Their Histopathological Effects on Anodonta cygnea (Linea, 1876) in Kabul River, Khyber Pakhtunkhwa, Pakistan

Abstract

The present investigation aimed to assess the concentrations of selected heavy metals in water and sediments and their bioaccumulation in tissues of freshwater mussels and their histopathological effects on the digestive gland, gills, and gonads of Anodonta cygnea. Water, sediments, and freshwater mussel samples were collected at four sites, that is, reference and polluted sites, along the Kabul River, Khyber Pakhtunkhwa. The polluted sites were receiving effluents from the industrial, agricultural, municipal, and domestic sources. The order of metals in the water was Zn > Pb > Ni > Cu > Mn > Fe > Cr > Cd, in sediments the order was Fe > Zn > Cr > Ni > Mn > Pb > Cu > Cd, and in the soft tissues the order was Fe > Zn > Mn > Pb > Cu > Cr > Ni > Cd. Histopathological alterations observed in polluted sites of Kabul River were inflammation, hydropic vacuolation, and lipofuscin pigments (in digestive gland), gill lamellar fusion, dilated hemolymphatic sinus, clumping, and generation of cilia and hemocytic infiltration (in gills), and atresia, necrosis, granulocytoma, hemocytic infiltration, and lipofuscin pigments (in gonads). The histopathological alterations in the organs of Anodonta cygnea can be considered as reliable biomarkers in biomonitoring of heavy metal pollution in aquatic ecosystems.

Land Use and Land Cover Changes in a Human-Wildlife Mediated Landscape of Save Valley Conservancy, South-Eastern Lowveld of Zimbabwe

“…Shivakumar et al (2014) from india and Ahmad et al (2015) from Karachi fish harbor reported higher metal concentrations due to the anthropogenic activities and industrial waste dumping into the natural water bodies. Our findings were also in accordance to the findings of Javed and Usmani (2013), Izuchukwu et al (2017) and Khan et al (2018) who reported that heavy metals bioaccumulate in the fish bodies that may be used as bioindicator of environmental pollution.…”

“…6). Khan et al (2018) reported histopathological alterations in digestive gland i.e atrophy, hydropic vacuolation, necrosis, and lipofuscin which was in accordance of our results. Damage to intestinal tissue, particularly to enterocytes and villi structures, was detected histologically in tilapia by Younis et al (2013).…”

“…Industrialization and urbanization play a major roll in dumping of heavy metals in the environment up to the alarming level (Hussain et al 2014) especially in the Indus River and its tributaries. Fatoki and Mathabatha (2001), Qadir et al (2009), Qadir and Malik (2011), Javed and Usmani (2013), Cardwell et al (2013), Khan et al (2018) and many other researchers have worked on heavy metal contamination but the information are limited. The objective of this study was to investigate the concentration of heavy metals in different organ of Labeo…”

Partitioning of heavy metals in different environmental and biotic components in the coastal waters of the Straits of Malacca, Peninsular Malaysia

“…However, the results of study was comparable to those reported by Yap et al (2002Yap et al ( , 2003 who also noted that sediments in Gula estuary had significantly lower metal concentrations compared to those in Juru area. Accumulation of non-degradable pollutions such as heavy metals in sediments over a long period of time can exceed the concentrations in water columns (Lyons and Fitzgerald, 1980;Barron, 1995;Yi et al, 2008;Khan et al, 2018). Under this condition, sediments can serve as a sink as well as a source of pollutants such as heavy metals.…”

“…Kontas (2008) and Khan et al (2018) suggested that the mobilization of particulates from the bottom layer provided food particles to planktonic organisms, including copepods, although they were not in actual contact with the sediment. In fact, increased phytoplankton and chlorophyll a in the water column formed an important food source for the zooplankton partly due to mobilization of nutrients, especially inorganic nitrogen and phosphorus together with heavy metals from the enriched bottom sediment (Kontas 2008;Khan et al, 2018). In a polluted area, the bottom sediment plays a significant role in accumulation, storage and transport of metals among different environment and biotic compartments (Solomon et al, 1987).…”