Open Access ISSN: 2165-784X
Journal of Civil & Environmental Engineering Research Article
Volume 10:4, 2020
DOI: 10.37421/jcce.2020.10.349
Abstract
Greenhouse assessment of the effect of oil on Chromolaena odorata ability to remove PCB from soil treated with transformer oil co-contaminated
with Aroclor 1260 was done.
Method: Plants were transplanted into one kilogram of soil contained in 1L pots differently containing 100, 200, and 500 ml of transformer
oil (T/O), co-contaminated with 100 ppm of Aroclor. Treatments were done in two microcosms; direct contamination and soil cultured method.
Measured plant growth parameters showed that C. odorata growth was affected by the different concentrations of oil. Inhibition of plant growth by
oil increased with concentrations.
Results: At the end of six weeks, plant growth was affected in T/O amended soil. Plants size was increased by 1.4, 0.46 and -1.0% in direct
treatment and 17.01, 6.09 and 1.08% in soil culture at the 100, 200 and 500 ppm respectively. Untreated control showed a 43.07% increase. Slight
PCB recovery was observed in root tissues of C. odorata but soil PCB was reduced by 66.6%, 53.2%, 41.5% and 77.3%, 74.7%, 58.8% at both
treatments in their respective concentrations of oil. However, unplanted control was reduced by 21.4% and 16.7% in the two treatments at 100
ppm of oil.
Conclusion: This study has shown that with improved agronomic practices, there is a possibility of phytoremediation of soil PCB from PCB
contained transformer oil contaminated soil using Chromolaena odorata, hence it should be optimized in the field.
Keywords: Phytoremediation • Transformer oil contamination • Chromolaena odorata • PCB • Soil remediation • South Africa.
Effect of Oil on Phytoremediation of PCB Co-Contamination in
Transformer Oil Using Chromolaena odorata
Anyasi RO
1
*, Atagana HI
2
and Anyasi Raymond JO
3
1
Department of Environmental Sciences, University of South Africa, Pretoria, South Africa
2
Institute for Science and Technology Education, University of South Africa, Pretoria, South Africa
3
School of Management and Technology, Tshwana University of Technology, Pretoria South Africa
*Address for Correspondence: Anyasi RO, Department of Environmental
Sciences, University of South Africa, Pretoria, South Africa, Tel: + 0504619676;
E-mail: eanyasro@unisa.ac.za
Copyright: © 2020 Anyasi RO, et al. This is an open-access article distributed
under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the
original author and source are credited.
Received 01 July, 2019; Accepted 13 July, 2020; Published
20 July, 2020
Introduction
Advances in science and technology have enabled man to exploit natural
resources largely, generating unprecedented disturbances in global elemental
cycles [1]. The relatively recent introduction of man-made toxic chemicals,
and the massive relocation of natural materials to different environmental
compartments; soil, ground water, and atmosphere, has resulted in severe
pressure on the self-cleansing capacity of recipient ecosystems. Various
accumulated pollutants are of concern relative to both human and ecosystem
exposure and potential impact. There have been efforts by many authorities
in different countries to control the release of contaminants [2], and to
accelerate the breakdown of existing contaminants by appropriate remediation
techniques. Such techniques and technologies are marred by various
disadvantages and usually require relatively high capital expenditure and man
power as well as long term operating cost. Hence, recent interests are geared
towards developing more cost effective approach to treat large volumes of
contaminated natural resources such as soil, ground water and wetlands [3].
Bioremediation is the use of plants and the associated rhizospheric
microorganisms to remove, transform, or contain toxic chemicals located in
soils, sediments, ground water, surface water, and even the atmosphere [4].
This technique is currently used to treat many classes of contaminants including
petroleum hydrocarbons, chlorinated solvents, pesticides, explosives, heavy
metals and radionuclides, and landfill leachates [1]. Biological method has been
used for hundreds of years to treat human waste, reduce erosion, and protect
water quality [5], until about 25 years ago which saw some significant rise in
the use of plants known as phytoremediation in the removal of contaminants
from the environment [6]. In the present study, C. odorata (Siam weed), was
grown in Aroclor 1260 amended transformer oil-contaminated soil in order to
study the effect of oil on the ability of plants in the remediation of soil-PCB
from a transformer oil impacted soil. This is of importance as literatures have
only reported on plants remediation of PCB without considering the impact of
co-contamination of the oil, considering the fact that PCB has not been used
in isolation [7,8].
Polychlorinated biphenyls (PCBs) are a family of anthropogenic organic
compounds that is persistent in the environment causing its bioaccumulative
phenomenon that enables the contaminant to be found in every part of the
environment. PCB is commercially produced by direct chlorination of biphenyls
[9]. A good commercial form of PCB is Aroclor 1254 and 1260, although other
brand names exist [10]. Various negative health effects in humans as well as
the animals are linked to PCB compounds, this call for an urgent action on how
the compound can be removed from the environment [11,12]. The physico-
chemical properties of PCB depend on the congener composition, but generally
they are resistant to acids and bases, resistant to oxidation and hydrolysis,
thermally stable, excellent electrical insulators, sparingly soluble in water and
have low flammability [13]. These characteristics conforms the usefulness
of PCBs in diverse industrial applications, such as liquid components of
transformers, capacitors, heat-exchangers, and vacuum pumps. PCB mixtures
have also been used in open systems, such as plasticizers, drinking solvents,
water-proofing agents, sealing liquids, fire retardants and pesticides [14-17].
Transformer oil also known as insulating oil is a highly refined mineral oil