Chapter 10

Metal(loid)s Toxicity

and Bacteria Mediated

Bioremediation

Sushant Sunder,¹ Anshul Gupta,¹ Mehak Singla,¹

Rohit Ruhal² and Rashmi Kataria^1,*

10.1 Introduction

Pollutants are impurities that enter the natural environment beyond permissible limits and have

a notable negative impact on the inhabitants. These chemical compounds could be new to the

environment or present naturally, such as metal pollution in mining regions, volcanic eruptions, air

fallout, sea salt particles, etc. Industrialization and aggressive utilization of natural resources have

produced a number of contaminants or pollutants that are either biodegradable or non-biodegradable

in nature. Contaminants including toxic metals, heavy metals, insecticides, herbicides and

radioactive compounds are among the pollutants that have caused significant environmental and

health problems. It has been observed that pollutants are being continuously released from industrial

waste and anthropogenic sources to the environment, and this waste circulates from the physical

environment to plants, plants to animals, and so on enter the food chain to reach humans.

10.2 Toxic Metals

The metabolic processes in plants, animals and humans are impacted by different toxic metals.

Copper (Cu), Cobalt (Co), Zinc (Zn), Nickel (Ni) and Chromium (Cr) are examples of potentially

hazardous metals, and some of these serve both as micronutrients and essential components of redox

reactions. These metals are important for regulation, electrostatic interactions and cofactor’s stability

in many compounds and reactions. Trace components, also known as heavy metals, are necessary

for the smooth functioning of the human body metabolism; however, their harmful effects cannot be

neglected if present in excessive quantities. The high-density metallic elements are toxic in nature,

even in relatively smaller quantities. The detrimental effects of these toxic metals are discussed in

Table 10.1. Any amount of lead (Pb) may have a negative impact on the body. In some cases, lighter

1 Department of Biotechnology, Delhi Technological University (DTU), Bawana Road, Delhi 110042.

2 Department of Biological Sciences. 1250 W Wisconsin Avenue, Marquette University, Milwaukee, Wisconsin 53233,

USA.

* Corresponding author: rashmikataria@dtu.ac.in