Bioaccumulation and Biosorption: The Prospects and Future Applications 57
general objective of this chapter is to look at the biosorption and bioaccumulation potentials for
heavy metal removal from contaminated environments (Singh and Kumar 2020). The most utilized
heavy metal removal technologies from water and wastewater are discussed.
4.1.1 Heavy Metals in the Environment
Recent advances in civilization have resulted in an overabundance of heavy metals entering the
ecosystems. In both aqueous and terrestrial contexts, heavy metals can form indeterminate mineral
and organometallic linkages (Yaashikaa 2020, Abdul Jaffar et al. 2015). Steel mills, plating facilities,
tanning plants, chemical fertilizer, pesticide manufacturing plants, fabric dye plants, electroplating
plants, motor and power engineering plants and battery and accumulator manufacturing plants
produce wastewater (Ahmed et al. 2021). Heavy metals released into the environment have high
mobility. Plants may absorb them, and they wind up in the digestive tracts of animals and humans
(Al-Ansari et al. 2021). Due to their harmful effects on certain elements of the environment and
bioaccumulation in the food chain, heavy metals constitute a significant hazard to living beings
(Arroyo Herrera et al. 2021).
4.1.2 Heavy Metals in Surface Water
Industrial and municipal wastewater carries heavy metals into surface water. Leaching of chemical
pollutants from landfills and deposition of atmospheric specific matter can also pollute surface
water (Bai et al. 2019). Water contamination can also be caused by leaching of mineral fertilizers
and pesticides from the soil. Heavy metals can be found in the following forms in the aquatic
environment:
• Ionic form (the most harmful to living organisms);
• Ion linked with a variety of ligands (complex compounds);
• Precipitated molecules.
In surface water, many heavy metals bioaccumulate. Algae collect significant amounts of
metals (particularly manganese and lead).
4.1.3 Heavy Metals in the Soil
Metal pollutants in the soil are caused by industrial and power engineering, as well as atmospheric
pollutants and landfilling. Metals can be introduced to the soil through fertilizers with sewage
sludge and insecticides. Soil contamination occurs because of transportation along with route
systems (Bai et al. 2016). Metals in the soil can be dissolved, transported and taken up by various
species depending on soil conditions, such as pH. Metals are present in the soluble form at lower
pH—in acidic soils—and hence are more available to plants. High metal concentrations in soils
always cause a disruption in chemical balance, which hinders the functioning of specific ecosystems
(Baselga Cervera 2018). Metals accumulating in soils prevent soil microbes from growing.
Microorganisms’ basic physiological processes associated with the breakdown and modification of
organic compounds are harmed.
4.1.4 Heavy Metals in Atmosphere
Heavy metals in the atmosphere are added mainly by emissions of specific matter from industry,
transportation and power generation (Bindschedler et al. 2017). The pollution of the atmosphere has
a worldwide scope. This is due to the small size of molecules, which allows them to float in the air
for lengthy periods and travel to far-flung corners of the planet (Boriova et al. 2019). The quantity of
heavy metals emitted into the atmosphere is determined by the economic development of a country
as well as pollution control techniques. Airborne contamination by heavy metals has a negative