Bioremediation Methods for the Recovery of Lead-Contaminated Soils: A Review

Abstract

Currently, the pollution of soils by heavy metals is a problem of paramount relevance and requires the development of proper remediation techniques. In particular, lead is a frequently detected soil contaminant that poses adverse effects to the environment and human health. In this review, we provide an overview of the bioremediation treatments promoted by plants (phytoremediation), fungi, or bacteria that could be applied to areas polluted by lead. These restoration processes have the advantage of being environmentally friendly and cost-effective solutions that exploit plants to immobilize and extract contaminants from soil and water, and fungi and bacteria to degrade them. Phytoremediation is an extensively studied and mature practice, with many in-the-field applications where numerous plant species have been employed. In contrast, bioremediation processes promoted by fungi and bacteria are very promising but, up to now, studies have been mostly performed at a laboratory scale with only a few implementations in real-world situations; therefore, further research is needed.

Unraveling the Underlying Heavy Metal Detoxification Mechanisms of Bacillus Species

“…Its exposure occurs by food, water, and inhalation, which affects the circulatory, gastrointestinal, reproductive, neurological, muscular, kidney, and genetic systems [ 123 ]. Dose and exposure time are prime factors [ 247 ]. The permissible level of Pb in drinking water is <10 µL/L [ 230 ].…”

Microbial Resources, Fermentation and Reduction of Negative Externalities in Food Systems: Patterns toward Sustainability and Resilience

“…[38,39] Beneficial plant-microbe interactions to breed 'microbe-optimized plants' [32] Microalgae and new application in food, feed, and nutraceuticals chains [40,41] Microbial-based tailored solutions for sustainable feeding regimen [42] As reported in the scientific literature, it is possible to find so many examples as to suggest a potential systemic application of microbes as mitigating agents in the primary production. In several cases, the target is the 'remediation' of negative trends: microorganisms selected to reduce carbon dioxide [19,22], bioconversion of pollutants in water via microbial [19,26,27], microbial-driven bioremediation of soil [28,29], and microbial-based decomposition of endocrine disruptors from trophic chains [22]. In addition, we can find 'green' microbial alternatives to standard solutions, such as substitute to antibiotic [35][36][37], pesticides [32,34], fertilizers/stimulants [32,33], feeding regimen [42], nitrogen sources [19], protein production [19,25], and to make water potable [30,31].…”

Bioremediation of Lead in Water by Two Pure Microorganisms and Bacteria-Yeast Consortium

“…The continuous environmental pollution by heavy metals is a problem of high importance at international level, they are chemical elements that have a density greater than 5 g/cm 3 and are not biodegradable. They are found naturally in the earth's crust at low concentrations, some of which are nutrients for flora and fauna, but at high concentrations under certain conditions can severely degrade the environment, affecting people (Caviedes et al, 2015;Rigoletto et al, 2020;Shaban et al, 2016).…”