**1. Introduction**

Although the contamination of water resources is a widely recognized fact and a critical universal issue, it is still a common occurrence [1, 2]. The major sources of aquatic as well as terrestrial and atmospheric systems contamination are effluent outfalls and gas emissions from industries, agricultural activities and refinery contaminants [2] that end up entering water bodies via rain water, soil and groundwater systems. The contaminants comprise (i) inorganic chemicals such as metals, extensively used in a wide variety of industries, including metal plating, mining, batteries, electroplating, ceramic, chemical manufacturing of paint and coating, health-care

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. © 2018 The Author(s). Licensee IntechOpen. 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.

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products, extractive metallurgy, petrochemical and fine chemistry [3] and (ii) organic chemicals such as industrial solvents, volatile organic compounds (VOCs), pharmaceuticals, insecticides, pesticides, dyes [1] and food processing wastes [2].

similar metals are the two major causes of their toxicity. For instance, lead can replace calcium in the bone and other tissues where it is required, whereas cadmium can replace zinc in some

Biosorption of Multicomponent Solutions: A State of the Art of the Understudy Case

http://dx.doi.org/10.5772/intechopen.72179

53

More recently, the discharge of organic chemicals such as pharmaceutical products [8], volatile organic compounds, aromatic hydrocarbons [9] and dyes [10] has also caught the world attention, due not only to their persistence, toxicity and mobility in the environment but also to their

Despite the fact that every single aspect connected to pharmaceutical efficiency and patient security to be under scrutiny [8], the complete extent and consequences of the presence of emerging pollutants in the environment matrices and on the wellbeing of all forms of life are not yet sufficiently studied in terms of toxicity, degradability and occurrence, allowing it to

Pharmaceutical compounds have been detected at trace concentrations (ng/L levels) in a wide variety of environmental water samples including sewage flows, rivers, lakes, groundwater aquifers and drinking water [11]. Although the concentrations of these pharmaceutical products have been detected at trace concentrations in a broad variety of aquatic environments, their continuous input may compose a potential threat for living organisms. Furthermore, pharmaceutical products are often synthesized in order to remain unchanged during their passage through the human body, which makes them and their metabolites persistent pollut-

The increased use of organic compounds in almost, if not all, industrial sectors as well as in household activities and consequent discharge and accumulation into the environment has increased in an extremely significant way in the past years [2, 12–14]. Most of these compounds are extremely toxic to humans due to (i) their general carcinogenic and mutagenic properties, (ii) their capacity to form intermediates with the same or even the higher level of toxicity [15]

per year, of which about 2% are discharged directly to effluents from manufacturing operations, whereas 10% are discharged from textile and related industries [16]. The dye lost through the practices of textile industry poses a serious problem for wastewater management and treat-

Although chemical precipitation, reverse osmosis, complexation, solvent extraction, ion exchange, adsorption on granular activated carbon, condensation, thermal degradation, oxidation and incineration comprise the conventional abiotic methods usually employed to remove different types of pollutants from effluents [7], biotic methods such as water purification treatments and standard sewage as well as auxiliary reed bed and wetlands approaches [18] have been used for many years. The outstanding ability of microorganisms to detoxify organic and inorganic pollutants [15, 18] and to the downside of the abiotic methods which can be summarized (i) as expensive, (ii) not environmentally friendly and (iii) usually dependent on the concentration of the waste [7]

dyes are currently marketed with an annual production exceeding 7 × 105

tons

tons of dyes are discharged

and (iii) their persistence and mobility into the different environmental matrices [7].

ment, since it can reach loss values as high as 50%. About 2 × 105

makes them an attractive alternative to decontaminate contaminated solutions.

annually into the environment, especially into water bodies [17].

proteins that require it for their structure as well as function [2].

remain unregulated.

More than 1 × 105

ants in environmental matrices [8].

widespread use and discharge as well as their impact on all forms of life.

The non-natural redistribution of these chemicals has culminated first in their increasing discharge and accumulation into the different environmental matrices and second in the development of environmental and health problems (**Figure 1**) [3, 4]. Therefore, there is a constant search for economical, efficient, effective and eco-friendly processes able to not only decontaminate wastewaters but also ensure that the presence of the pollutants discharged into the aquatic systems is below the permissible limits.

In the past decades, great attention and concern have been given to the continuous and increasing discharge of metals such as chromium, mercury, lead [2], cadmium and nickel into the environment. This increasing concern is due to metals' inherent properties, (i) persistence in nature, (ii) tremendous toxicity even at low concentrations and (iii) tendency for bioaccumulation via food chain in living tissues, which may culminate in the triggering of several serious diseases and health disorders [3].

Chromium compounds, for instance, are carcinogenic and nephrotoxic in nature. Exposure to mercury and lead may provoke allergic skin reaction, eventual negative reproductive effects as well as damage to brain function and disruption of the nervous system [2]. Cadmium exposure may cause severe damage in different organs including the testis, lungs, liver and kidneys and even lead to infertility [5, 6]. It also affects the action of enzymes and induces genomic instability through complex and multifactorial mechanisms, such as proteinuria, and an increase in the frequency of kidney stone formation, eventually causing certain types of cancer (group B1) [3]. Besides being listed in the carcinogenic group B2, nickel has been implicated as a teratogen nephrotoxin and an embryotoxin element. Acute and chronic nickel exposure can cause several disorders such as cyanosis, chest pain, tightness, pulmonary fibrosis, skin dermatitis, lungs and kidney damage and renal oedema [7].

The capacities of metals to disrupt the function of fundamental biological molecules, such as DNA, proteins and enzymes, and to displace certain metals essential for the cell viability by

**Figure 1.** Sources of pollution by organic and inorganic chemicals, their transport, transformation, fate and impact into the different environmental matrices.

similar metals are the two major causes of their toxicity. For instance, lead can replace calcium in the bone and other tissues where it is required, whereas cadmium can replace zinc in some proteins that require it for their structure as well as function [2].

products, extractive metallurgy, petrochemical and fine chemistry [3] and (ii) organic chemicals such as industrial solvents, volatile organic compounds (VOCs), pharmaceuticals, insecticides,

The non-natural redistribution of these chemicals has culminated first in their increasing discharge and accumulation into the different environmental matrices and second in the development of environmental and health problems (**Figure 1**) [3, 4]. Therefore, there is a constant search for economical, efficient, effective and eco-friendly processes able to not only decontaminate wastewaters but also ensure that the presence of the pollutants discharged into the

In the past decades, great attention and concern have been given to the continuous and increasing discharge of metals such as chromium, mercury, lead [2], cadmium and nickel into the environment. This increasing concern is due to metals' inherent properties, (i) persistence in nature, (ii) tremendous toxicity even at low concentrations and (iii) tendency for bioaccumulation via food chain in living tissues, which may culminate in the triggering of several serious diseases

Chromium compounds, for instance, are carcinogenic and nephrotoxic in nature. Exposure to mercury and lead may provoke allergic skin reaction, eventual negative reproductive effects as well as damage to brain function and disruption of the nervous system [2]. Cadmium exposure may cause severe damage in different organs including the testis, lungs, liver and kidneys and even lead to infertility [5, 6]. It also affects the action of enzymes and induces genomic instability through complex and multifactorial mechanisms, such as proteinuria, and an increase in the frequency of kidney stone formation, eventually causing certain types of cancer (group B1) [3]. Besides being listed in the carcinogenic group B2, nickel has been implicated as a teratogen nephrotoxin and an embryotoxin element. Acute and chronic nickel exposure can cause several disorders such as cyanosis, chest pain, tightness, pulmonary fibrosis, skin dermatitis, lungs and

The capacities of metals to disrupt the function of fundamental biological molecules, such as DNA, proteins and enzymes, and to displace certain metals essential for the cell viability by

**Figure 1.** Sources of pollution by organic and inorganic chemicals, their transport, transformation, fate and impact into

pesticides, dyes [1] and food processing wastes [2].

aquatic systems is below the permissible limits.

and health disorders [3].

52 Biosorption

kidney damage and renal oedema [7].

the different environmental matrices.

More recently, the discharge of organic chemicals such as pharmaceutical products [8], volatile organic compounds, aromatic hydrocarbons [9] and dyes [10] has also caught the world attention, due not only to their persistence, toxicity and mobility in the environment but also to their widespread use and discharge as well as their impact on all forms of life.

Despite the fact that every single aspect connected to pharmaceutical efficiency and patient security to be under scrutiny [8], the complete extent and consequences of the presence of emerging pollutants in the environment matrices and on the wellbeing of all forms of life are not yet sufficiently studied in terms of toxicity, degradability and occurrence, allowing it to remain unregulated.

Pharmaceutical compounds have been detected at trace concentrations (ng/L levels) in a wide variety of environmental water samples including sewage flows, rivers, lakes, groundwater aquifers and drinking water [11]. Although the concentrations of these pharmaceutical products have been detected at trace concentrations in a broad variety of aquatic environments, their continuous input may compose a potential threat for living organisms. Furthermore, pharmaceutical products are often synthesized in order to remain unchanged during their passage through the human body, which makes them and their metabolites persistent pollutants in environmental matrices [8].

The increased use of organic compounds in almost, if not all, industrial sectors as well as in household activities and consequent discharge and accumulation into the environment has increased in an extremely significant way in the past years [2, 12–14]. Most of these compounds are extremely toxic to humans due to (i) their general carcinogenic and mutagenic properties, (ii) their capacity to form intermediates with the same or even the higher level of toxicity [15] and (iii) their persistence and mobility into the different environmental matrices [7].

More than 1 × 105 dyes are currently marketed with an annual production exceeding 7 × 105 tons per year, of which about 2% are discharged directly to effluents from manufacturing operations, whereas 10% are discharged from textile and related industries [16]. The dye lost through the practices of textile industry poses a serious problem for wastewater management and treatment, since it can reach loss values as high as 50%. About 2 × 105 tons of dyes are discharged annually into the environment, especially into water bodies [17].

Although chemical precipitation, reverse osmosis, complexation, solvent extraction, ion exchange, adsorption on granular activated carbon, condensation, thermal degradation, oxidation and incineration comprise the conventional abiotic methods usually employed to remove different types of pollutants from effluents [7], biotic methods such as water purification treatments and standard sewage as well as auxiliary reed bed and wetlands approaches [18] have been used for many years. The outstanding ability of microorganisms to detoxify organic and inorganic pollutants [15, 18] and to the downside of the abiotic methods which can be summarized (i) as expensive, (ii) not environmentally friendly and (iii) usually dependent on the concentration of the waste [7] makes them an attractive alternative to decontaminate contaminated solutions.
