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

M.U Ibezim-Ezeani,O.C Ihunwo

doi:10.4314/jasem.v24i4.26

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

Highlights

Terrestrial heavy metals are usually washed into the aquatic ecosystem through industrial and municipal runoffs and makes estuaries and coastal ecosystems the major recipient and accumulators of aquatic pollutant (McComb et al, 2014)
Previous research on the treatment of heavy metals from water by electro-phytoremediation technique proposed that under electrified condition, maximum amount of Cd and Cu were accumulated in the aerial parts of Eichhornia crassipes (Puthenveedu et al, 2017)
The present work is designed to investigate the accumulation of lead (Pb), nickel (Ni), cadmium (Cd) and chromium (Cr) in surface water and plant, and assess the phytoremediation potential of Eichhornia crassipes

Summary

Introduction

Terrestrial heavy metals are usually washed into the aquatic ecosystem through industrial and municipal runoffs and makes estuaries and coastal ecosystems the major recipient and accumulators of aquatic pollutant (McComb et al, 2014) Human activities such as oil and gas exploration, boat fabrication and maintenance and other industrial activities have led to the input of these elements into the ecosystem (Freije, 2015; Turner, 2014; Turner and Rees, 2016). Some important notes were taken; over 80 % of the total amount of metals removed was accumulated in the roots, of which 30 – 52 %was adsorbed onto the root surface; 73 – 98% of the total metal assimilation by water hyacinth took place in the roots This confirmed the difficulty of translocation of a reasonable amount of metals from the root to other parts of the plant. The present work is designed to investigate the accumulation of lead (Pb), nickel (Ni), cadmium (Cd) and chromium (Cr) in surface water and plant (root and shoot), and assess the phytoremediation potential of Eichhornia crassipes

Methods

Results

Conclusion