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Biology and Biotechnology of Environmental Stress Tolerance in Plants, Volume 3

incineration, catalytic destruction, adsorbent use, physical removal, and

eventual pollutant destruction. There is, however, a distance between labora­

tory research developments and commercial field applications. Therefore,

the present chapter focuses on the use of various soil microorganisms and

nematodes as a possible strategy that can contribute very effectively and

in an eco-friendly way for bioremediation and amelioration of polluted

soils. Further, it also delineates the challenges and limitations hindering the

widespread application of these clean green approaches involving microbes.

1.2 SOURCES AND TYPES OF POLLUTANTS IN THE

ENVIRONMENT AND THEIR FATE

The present scenario of high anthropogenic activity affected the environ­

ment which is the primary issue of the society. The pollutant that is natu­

rally occurring and foreign matter significantly affected the environment

and created adverse conditions for soil and water bodies. They all attract

substantial attention due to the environmental impacts they trigger. There

are many pollutants in soil, therefore the main pollutants in the soil can be

broadly categorized as of three types, i.e., organic, inorganic pollutants, and

biological.

1.2.1 ORGANIC POLLUTANTS

The accrual of organic pollutants in the environment has an immense impact

on the solidarity of both land and marine habitats, creating more detrimental

effects on human health (UNEP, 2015). The wastes from the kitchen and

garden are generally categorized as biodegradable waste and mostly are of

organic types. However, the waste from the factories and agricultural runoff

are categorized as persistent organic pollutants (POPs). Stockholm conven-

tion classified 12 POPs into:

1. Industrial Chemicals: Polychlorinated biphenyls (PCBs) and

hexachlorobenzene.

2. Pesticides: Endrin, Heptachlor, Hexachlorobenzene, Mirex, Aldrin,

Chlordane, DDT, Dieldrin, Toxaphene.

3. By-Products: Polychlorinated dibenzofurans (PCDD/PCDF), hexa-

chlorobenzene, polychlorinated dibenzo-p-dioxins and PCBs.