pharmaceuticals in environment depends on various kinds of features such as
inherent physicochemical properties of pharmaceuticals, different environmental
factors like pH, light, temperature, etc. and their presence and biodegradation
potential of microorganisms via metabolic or co-metabolic pathways (Onesios et
al. 2009).
In recent times, terrestrial and aquatic ecosystems have brought about significant
and regulatory concern due to extensive detection of pharmaceuticals in the environment (Zuccato et al. 2010; Cardoso et al. 2014). Predominantly pharmaceuticals
have been detected in WWTP effluent, surface waters like river stream, and less
commonly in drinking water and groundwater (Rivas et al. 2012). Wastewater
treatment processes in WWTPs are not so efficient to remove pharmaceuticals;
thus, the effluent from wastewater treatment plant becomes major source point for
aquatic exposure to pharmaceuticals (Zuccato et al. 2005). Sewage sludge in the
form of biosolids and manure is used as a crop fertilizer, and for irrigation purpose
reclaimed water containing human and veterinarian pharmaceuticals is used which
penetrates to agricultural soil (Topp et al. 2008). Thus pharmaceuticals can leach into
groundwater through soil (Fent et al. 2006). They are also detected in coastal
seawater (Roberts and Thomas 2006). Over the past many decades’ awareness and
concern have grown toward this issue. Pharmaceutical compounds in the wastewater
treatment plants are controlled by various important mechanisms comprising sorption, desorption, aerobic and anaerobic biotransformation, biotic and abiotic degradation, and volatilization. Though some advanced methods like biodegradation
using capable microbes can be useful in the elimination of pharmaceutical
compounds. The use of microorganisms in biodegradation of pharmaceutical
compounds and other xenobiotics has been found as an eco-friendly and costefficient tool for wastewater treatment (Tran et al. 2013). Various microorganisms
like bacteria, fungi, and algae have been proved better degraders for contaminants in
wastewater (Ding et al. 2017; Castellet-Rovira et al. 2018; Woźniak-Karczewska et
al. 2018). Microorganisms have the capability to use target compounds as their
carbon, nutrients, and energy sources to degrade them or change into less harmful
compounds. Various researches have studied bacterial degradation and biotransformation of pharmaceutical compounds intensively in the past few years (Gauthier et
al. 2010; Sharma et al. 2017). In this chapter we will study these biodegradation
methods in detail.
13.2 Occurrence of Pharmaceuticals in the Environment
Pharmaceutical compounds enter in an environment by various routes as shown in
Fig. 13.2.
The major factors for determination of environmental exposure of various
concentrations of pharmaceuticals include the quantity of consumption, extent of
discharge in environment, and degree of persistence in environment. Pathways by
which the pharmaceutical compounds enter to environment can be different
depending on the consumption of pharmaceuticals. Pharmaceutical industries use
13 Pharmaceuticals: An Emerging Problem of Environment and Its Removal. . .
269
inherent physicochemical properties of pharmaceuticals, different environmental
factors like pH, light, temperature, etc. and their presence and biodegradation
potential of microorganisms via metabolic or co-metabolic pathways (Onesios et
al. 2009).
In recent times, terrestrial and aquatic ecosystems have brought about significant
and regulatory concern due to extensive detection of pharmaceuticals in the environment (Zuccato et al. 2010; Cardoso et al. 2014). Predominantly pharmaceuticals
have been detected in WWTP effluent, surface waters like river stream, and less
commonly in drinking water and groundwater (Rivas et al. 2012). Wastewater
treatment processes in WWTPs are not so efficient to remove pharmaceuticals;
thus, the effluent from wastewater treatment plant becomes major source point for
aquatic exposure to pharmaceuticals (Zuccato et al. 2005). Sewage sludge in the
form of biosolids and manure is used as a crop fertilizer, and for irrigation purpose
reclaimed water containing human and veterinarian pharmaceuticals is used which
penetrates to agricultural soil (Topp et al. 2008). Thus pharmaceuticals can leach into
groundwater through soil (Fent et al. 2006). They are also detected in coastal
seawater (Roberts and Thomas 2006). Over the past many decades’ awareness and
concern have grown toward this issue. Pharmaceutical compounds in the wastewater
treatment plants are controlled by various important mechanisms comprising sorption, desorption, aerobic and anaerobic biotransformation, biotic and abiotic degradation, and volatilization. Though some advanced methods like biodegradation
using capable microbes can be useful in the elimination of pharmaceutical
compounds. The use of microorganisms in biodegradation of pharmaceutical
compounds and other xenobiotics has been found as an eco-friendly and costefficient tool for wastewater treatment (Tran et al. 2013). Various microorganisms
like bacteria, fungi, and algae have been proved better degraders for contaminants in
wastewater (Ding et al. 2017; Castellet-Rovira et al. 2018; Woźniak-Karczewska et
al. 2018). Microorganisms have the capability to use target compounds as their
carbon, nutrients, and energy sources to degrade them or change into less harmful
compounds. Various researches have studied bacterial degradation and biotransformation of pharmaceutical compounds intensively in the past few years (Gauthier et
al. 2010; Sharma et al. 2017). In this chapter we will study these biodegradation
methods in detail.
13.2 Occurrence of Pharmaceuticals in the Environment
Pharmaceutical compounds enter in an environment by various routes as shown in
Fig. 13.2.
The major factors for determination of environmental exposure of various
concentrations of pharmaceuticals include the quantity of consumption, extent of
discharge in environment, and degree of persistence in environment. Pathways by
which the pharmaceutical compounds enter to environment can be different
depending on the consumption of pharmaceuticals. Pharmaceutical industries use
13 Pharmaceuticals: An Emerging Problem of Environment and Its Removal. . .
269