Assessment of Pb, Cd, Cr and Ni in Water and Water Hyacinth (Eichhornia crassipes) Plant from Woji Creek, Rivers State, Nigeria

Abstract

This study evaluates the levels of Pb, Cd, Cr and Ni and the potential ability of water hyacinth (Eichhornia crassipes) plant to bioaccumulate these metals in Woji Creek, Rivers State, Nigeria by collecting water and water hyacinth samples along a 1.3 km stretch of the creek between 2018 and 2019 for analysis. Water samples and plants were collected from five stations across the creek from June to October of both years. The trend of metal concentration in the surface water is Pb > Cr > Ni > Cd in 2018 and Pb > Ni > Cr > Cd in 2019. In 2018, metal concentration in the root are in the order: Cr > Ni > Pb > Cd, while the trend for the shoot is Cr > Pb > Ni > Cd. In 2019, Cd was detected in the roots ranging from 1.009 ± 0.001 to 9.545 ± 0.006, while Pb ranged from 0.298 ± 0.006 mg/kg to 121.006 ± 0.005 mg/kg. There was substantial bioaccumulation of Pb, Ni and Cr in the roots with most plant roots having BCF > 1. In the shoot, BCF was > 1 for Pb and Cr only, while Ni had BCF < 1. The findings from this research also assert that the E. crassipes can be used in the application of rhizofiltration as phytoremediation technique in Woji creek.

Keywords: Metal accumulation, phytoremediation, Translocation, Bioconcentration, Woji creek