Content of zinc and lead in water and in algae from selected Black Sea bays near Sevastopol

Abstract

For many years there has been intensified human pressure in the region of Sevastopol, arising out of its strategic role as the main city in the region as well as a port where the Russian or Soviet Black Sea fleet was stationed. The industry in Sevastopol, municipal sewage as well as agriculture are important sources of pollutants that enter the Black Sea in the region of this city. In terms of shaping the environmental protection policy (not only in the research region but in the whole basin), it is important to conduct monitoring research connected with the pollution of the Black Sea in regions with different levels of human pressure. The aim of this study was to assess the content of zinc and lead in water and in algae from selected Black Sea bays near Sevastopol. The samples of water and algae were collected in August 2012 from eight bays of Sevastopol (Galubaja, Kozacha, Kamyshova, Kruhla, Striletska, Pishchana, Pivdenna and the Sevastopol Bays) as well as one sample from the open sea near Fiolent. Cystoseira barbata and Ulva rigida algae were taken from the same places. The collected water samples were conserved in situ and after being brought to the laboratory their zinc and lead contents were determined. The collected algae were rinsed in distilled water, dried, and then homogenized and mineralized. The lead content was determined in mineralisates by AAS method with electrothermal atomization, and the zinc content was determined using the ICP-OES method. The zinc content in water ranged from 36.43 to 233.3 g Zn dm, and the lead content was between 1.32 and 38.32 g Pb dm. Considerable differences in contents of the studied elements in water of individual bays were found. Variability of zinc and lead concentration in the studied water samples was 69 and 112%, respectively. The highest zinc contents were found in water from the Striletska, Kozacha, and Sevastopol Bays, and the highest lead contents from the Kozacha and Kruhla Bays. Their lowest concentration was found in the water collected in the open sea. Moreover, the lower zinc concentration was in water from Pivdenna and DOI: 10.2428/ecea.2016.23(1)1 ECOL CHEM ENG A. 2016;23(1):7-19 1 Department of Agricultural and Environmental Chemistry, University of Agriculture, al. A. Mickiewicza 21, 31–120 Kraków, Poland, email: niemiecm@tlen.pl, rrkielia@cyf-kr.edu.pl, komorowska.monika@interia.pl 2 Institute of Biology of the Southern Seas of Ukrainian National Academy of Sciences, Sevastopol, Ukraine, email: kunast@rambler.ru * Corresponding author: rrkielia@cyf-kr.edu.pl Pishchana Bays, and the lowest lead concentration was found in the Galubaja and Pishchana Bays. The zinc content in the algae ranged between 6.517 and 30.21 mg kg. The Cystoseira barbata algae contained over twice more zinc than the Ulva rigida. The lead content in the algae ranged between 0.567 and 7.692 mg Pb kg. Compared with the Ulva rigida, almost a half more lead was found in the Cystoseira barbata. No statistically significant correlation between the content of the studied elements in water and the algae biomass was observed. However, a significant positive correlation between the content of these metals in both species of algae was found. The values of the zinc bioaccumulation coefficient varied from 32 to 642, and of lead from 30 to 1,273.