TOXIC EFFECT OF BENZO[A]PYRENE ON SPRING BARLEY (HORDEUM SATIVUM DISTICHUM)

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7408-05-8 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 32, 687-692 pp, DOI: DOI: 10.5593/sgem2017/32/S13.089

ABSTRACT

This article is devoted to the assessment of toxic effect of benzo[a]pyrene (BaP) on spring barley (Hordeum sativum distichum) grown in background control Haplic chernozem and that spiked with various doses of BaP (20, 200, 400 and 800 μg/kg) equivalent to 1, 10, 20 and 40 levels of maximal permissible concentrations (MPC). The experimental soil samples were planted every spring and incubated outdoor during 4 years. During the experimental time (almost 4 years), concentrations of BaP decreased by 80-87% in the soil samples spiked with high doses, while only about 41% BaP degraded in the soil with lowest dose of the pollutant. Concentration of BaP in the background and ACN-control soils decreased finally by about 54 and 60% respectively that is also much less compared to highly contaminated soils. Substantial amounts of BaP were accumulated in the spring barley plants. Its concentrations in roots and vegetative part depended on the initial BaP contamination and reduced simultaneously with diminish of BaP concentration in the related spiked samples. The coefficients BaP bioaccumulation in roots and vegetative part fluctuated within 0.035÷0.065 and 0.015÷0.025 respectively at the 1st season and reduced about twice to the end of the experiment. Meantime those values in control soils vice-versa were low at the beginning (0.03 and 0.01 respectively) but increased twice to the 4th season that is explained by the change of BaP availability in the soils.

Keywords: benzo[a]pyrene, degradation rate constant, bioaccumulation factor, soil contamination, plants