Phytoremediation Capacity Assessment of Copper (Cu) and Lead (Pb) Contaminated Soils using Helianthus annuus L. (Sunflower Plant)

Abstract

INTRODUCTION

Heavy metal contamination is an overlooked, dangerous by-product of industrialization that harms human and environmental health. Phytoremediation is a proven cheap alternative to cleaning up heavy metals. To significantly contribute to heavy metal pollutant research, this paper aims to assess the phytoremediating capability of the sunflower plant (Helianthus annuus L.) against two prominent heavy metals, Cu and Pb, using artificially infused and naturally-contaminated soils.

METHODS

Two sets of experiments were performed wherein healthy soil from Trece Martires, Cavite was used for the artificially infused setup and soil was collected from Binakayan, Cavite for the naturally contaminated soil setup. initial AAS analysis for the two setups revealed 2.14mg/ kg Pb and 6.22mg/kg Cu were present in the artificially infused setup while 2.03mg/kg Pb and 5.17mg/kg Cu were present in the naturally contaminated setup. Sunflower seeds were planted on both setups to determine and assess the phytoremediation capability of the specimen.

RESULTS

In the naturally contaminated soil, compared to the pre-analysis (mean of 4.615mg/L, SD 0.085mg/L), the post analysis showed significantly less heavy metal content (mean of 2.265mg/L, SD 0.035mg/L, p<0.005, t>2.132). in the metal-infused set-up, compared to the pre-analysis (mean of 4.18mgL, SD 0.165mg/L), the post analysis showed significantly less heavy metal content (mean of 3.41mg/L, SD 0.1mgL, p<0.035, t>2.132).

DISCUSSIONS

Overall, this study showed that sunflowers can be a promising phytoremediating agent against copper and lead contamination. Further in-depth studies should focus on (1) determining the biomolecular, metal-specific, phytoremediating mechanism of sunflower; and (2) further assess the phytoremediating property of fully-grown sunflowers through optimized experiments.