An assessment of the Causes of Lead Pollution and the Efficiency of Bioremediation by Plants and Microorganisms

Abstract

Abstract" rapid increase in mining industries associated with an increase in lead demand has resulted in the problem of lead poisoning. In this study, the initial causes of lead pollution were investigated. The results suggest that soil pollution from lead did not occur in urban and agricultural areas due to the efforts of decreased lead use and an increase in recycling however, serious pollution locally occurred in the areas where metallurgy and mining industries were present. Therefore, remediation must be carried out in the latter areas. Next, the efficiency of lead remediation by plants and microorganisms in the areas with increased lead pollution was assessed. The plants showing high potential have been developed, and phytoextraction is a promising process. However, a more cost-effective method is necessary to achieve widespread implementation. Thus, a novel remediation method the landfarming with immobilized microorganisms LIM method to overcome the problem of cost was proposed. The LIM method combines the immobilized technique with landfarming. "s the treatment period is short and the lead can readily be recycled from the soil, the LIM method may be a better alternative to phytoextraction for lead remediation. Keywords: Lead, Phytoextraction, "ioremediation, Landfarming© 2015 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. . IntroductionPollution by heavy metals has gradually worsened in "sian, "frican, and South "merican countries, partly due to the excessive use of pesticides for growing crops which may in turn lead to the pollution of groundwater and well water. "n investigation by the Food and "griculture Organization F"O /United Nations Environment Programme UNEP /World Health Organization WHO suggests that the number of patients with pesticide poisoning is approximately -million annually, and several thousand cases are fatal. In some "sian countries, wells reserved for drinking water were dug below the acceptable levels to avoid pesticide pollution, and consequently, many inhabitants developed arsenic poisoning [ , ]. Rivers and soils are also polluted by industrial wastes in those countries. In particular, wastes from metallurgy and mining industries contain various heavy metal ions, and wastes from leather industries contain cadmium and chromium. These wastes are typically exhausted and discarded in nearby rivers and in the air due to the lack of posttreatment equipment or strictly controlled landfill sites, resulting in detrimental groundwater and soil pollution."dditionally, environmental pollution by heavy metals has resulted in serious disease. In Japan, four historic cases of metal pollution occurring predominately in the s have been reported, which include ouch-ouch disease and Minamata disease. In , a mining company eliminated cadmium waste into a nearb...

The Strategy and Future of Biotechnology in Protecting the Global Environment

“…Pollution by toxic heavy metals, such as lead, cadmium, mercury, and hexavalent chromium, has also caused health problems [39,40]. For example, the production of lead-acid batteries has increased sharply owing to the increasing demand for automobiles; and the direct discharge of exhaust gases and wastewater containing high concentrations of lead from many metallurgical and mining operations with inadequate pretreatment, low-quality ore, or used sludge left on the soil has caused severe lead poisoning in areas surrounding these operations.…”

Introductory Chapter: Serious Pollution of Soil and Groundwater and the Necessity of Bioremediation

“…Other forms of health damage are caused by pollution from harmful heavy metals such as lead, cadmium, mercury, and hexavalent chromium [30][31][32][33][34]. For instance, contamination by lead and cadmium has recently become serious.…”

“…However, in the event of the removal of harmful heavy metals, microorganisms must be collected from the soil after the absorption of metals. In such a case, immobilization with alginate gels is more prominent than the self-immobilization method because microorganisms immobilized with alginate gel can be easily collected from the soil using a sieve as shown in photo B in Figure 1 [30].…”

Eficiencia en la reducción de Cromo por una bacteria silvestre en un tratamiento tipo Batch utilizando como sustrato agua residual del municipio de Pasto, Colombia

“…Al respecto, se reporta que el género Paenibacillus tiene la capacidad de secretar polímeros extracelulares como, polisacáridos que incrementan la afinidad con metales pesados, un caso relacionado fue descrito por Shiomi 32 en el que P. jamilae presenta un aumento en la afinidad por Plomo atribuida a los polisacáridos que secreta. Por otra parte, Rath, et al, indican que B. amyloliquefaciens aislada de una mina de cromita presenta la capacidad de producir una enzima extracelular (Cromato reductasa) que permite la reducción de Cromo hexavalente a Cromo trivalente cuando se encuentra en condiciones de estrés; por tal motivo se infiere que esta bacteria presenta un gran potencial en cuanto a procesos de biorremediación en ambientes contaminados con metales pesados 32,33 . Paralelamente, Das et al, reportan que B. amyloliquefaciens aislado de suelo de una mina de cromita en la India presentó alta tolerancia a Cr (VI) (900 mg/L) bajo condiciones óptimas, pH 7 y temperatura de 35° C 34 .…”