Spatiotemporal trends of heavy metal concentrations in fish of the River Morava (Danube basin)

Abstract

The aim of this study was to assess mercury (Hg), cadmium (Cd) and lead (Pb) contamination in muscle tissue of fishes over the longitudinal profile of the River Morava (Czech Republic, Danube basin) and to detect any temporal trends over the past 18 years. Fish samples were collected in 1992, 1998, 2000, 2003 and 2009 at 6 study sites situated just downstream of important pollution sources. Chub (Leuciscus cephalus L.) were selected as indicator species at 5 sites, and brown trout (Salmo trutta m. fario L.) at the uppermost site where chub do not occur. In total, muscle tissue of 175 specimens of chub and 19 specimens of brown trout were analysed. Concentrations of heavy metals ranged as follows: mercury 0.015-0.369 mg/kg; cadmium 0.001-0.254 mg/kg and lead 0.006-1.505 mg/kg. Mercury levels did not exceed the maximum allowed concentration in the Czech Republic (0.5 mg/kg). Content of cadmium and lead in fish muscle exceeded the maximum allowed levels (0.05 and 0.3 mg/kg respectively) in 11 and 4 samples, respectively. On average, the order of metal concentration in fish muscle was: Hg>Pb>Cd. No significant differences were found between sites along the longitudinal profile of the river. Significant differences were found, however, for the interannual comparison of cadmium and lead (but not mercury) at different sites (P < 0.05). A catastrophic flood in 1997 resulted in an increase in metal concentrations, especially cadmium and lead, in the following 1998 season. Our results indicate that the Morava river basin does not represent a threatening source of mercury, cadmium or lead for the River Danube downstream.

No relationship found between mercury and lead concentrations in muscle and scales of chub Squalius cephalus L.

“…2). These values are in accordance with the studies of Valová et al (2010;River Morava) and Spurný et al (2009;River Jihlava), in which total Hg concentrations in chub muscle tissue varied between 0.015 and 0.369 mg/kg and 0.040 and 0.133 mg/kg, respectively. Kružíková et al (2008) also found low Hg concentrations in chub muscle from the rivers Morava and Dyje in their study of 10 Czech rivers.…”

“…Dušek et al 2005;Houserová et al 2006;Havelková et al 2008;Kružíková et al 2008;Radnák et al 2009;Spurný et al 2009;Valová et al 2010). The chub Squalius cephalus L., a common freshwater cyprinid species, is considered the most suitable model fish species for such studies in rivers of the Czech Republic as they inhabit both clean and polluted waters (Baruš and Oliva 1995), occur along most of the longitudinal profile of Central European rivers, are omnivorous and have a body large enough for taking analytical samples of muscle tissue.…”

Studies on heavy metal contamination in Godavari river basin

“…Many countries in the world have experienced menace of metal pollution in water, and a large number of people have been affected. Causes of this pollution have been well documented by (Voutsa et al 1995;Newchurch and Kahwa 1984;Tariq et al 1993;Chukwujindu et al 2012;Samanidou and Papadoyannis 1992;Sharma et al 1992;Valová et al 2010). However, the primary sources of metal toxicity in surface water have been thought to be the natural occurrence and subsequent degradation of the environment (Jessica et al 2011).…”

An Ecological Assessment of the Pollution Status of the Danube River Basin in the Galati Region—Romania

“…Prepare and propose projects on priority hotspots in this aquatic system. Strengthen the capacities of environmental organisations and improve the international cooperation on sustainable management of the hydrosystem on trophic and sanitary basis as expressed by the findings of [20,21].…”