Phytoremediation of Lead Using Common Weeds in Enyigba Derelict, Ebonyi State, Nigeria
Samples of water and soils from Enyigba lead mine derelict is characterized by high levels of lead and other toxic
metals. This is as a result of anthropogenic activities involving extraction and processing of lead. Presence of lead in the
water, soil and plants pose a big threat to man as a member of the ecosystem. Toxicological effects of lead on humans
include inhibition of hemoglobin formation, sterility, hypertension and mental retardation in children, among others.
Remediation of polluted land involves physical methods such as excavation and mechanical separation processes, chemical
method such as extraction, liming, pH stabilization, complexing, oxidation and reducing processes and biological methods
such as bioremediation and phytoremediation. Many of these remediation processes are too expensive and time consuming.
Of all these processes, phytoremediation which employs the engineered use of green plants and their associated micro biota
for the in-situ treatment of contaminated soil and ground water is considered one of the best remedies. It is cost effective,
and aesthetically pleasing as the plants can be easily monitored and metals absorbed by the plants may be extracted from
harvested plant biomass and then recycled. Common weeds were grown in mapped areas of Enyigba derelict mine and they
were monitored for one year. The levels of metals absorbed by the plants were determined using X-ray fluorescence (XRF).
The result reveal accumulation of metals in the plant in the order of Cr > Mn > Cd > Pb. High translocation factors (TF) and
bioaccumulation factors (BAF) obtained from phytoremediation experiments using Chromoleaeceae Odarata, Imperata
cylindrical and Helianthus annus have the potential to clean up Pb, Ni, Mn and Cr from the contaminated soil.
Keywords- Phytoremediation, lead, toxicity, environment, XRF, Enyigba Pb-Zn mine