**1. Introduction**

In the world, about 33% of the industrial wastewater and 70% of the household sewage are untreated and directly discharged into rivers and lakes, while 80% of China cities have no sewage treatment facilities and water supplies in 90% of the cities, the water being contaminated [1]. There are 20 classes of categorized EPs accordingly with their origin; the prominent categories are pharmaceuticals (urban and protein production), pesticides (agriculture), disinfection

© 2016 The Author(s). Licensee InTech. 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. © 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.

by-products (urban and industry), wood preservation, and industrial chemical manufacturing. Different types of EPs show different properties as the organic substances divided in PBT for persistent bioaccumulative and toxic substances as POPs and persistent organic compounds. The EPs with more polarity are the pesticides, pharmaceuticals, and industrial chemicals. The inorganic compounds as poisonous metals are also found in polluted waters and finally the newly developed particulate contaminants as nanoparticles and microplastics [2].

systems as water column, sediment (mostly organic matter), and biota (lipids and proteins). It addresses single compound or mixtures reaching the equilibrium. The chemical activity relies on partition coefficients which are only available as experimental values. There are some models calculating partition coefficients from octanol–water systems (Kow-based models), and they were used for decades to estimate the concentration in different compartments.

Nowadays, the relationship of the polyparameters linear-free energy is used to calculate the partition coefficients of biological and nonbiological matrices including lipids and different proteins [4, 5]. The model helps to describe the diffusion and partitioning processes and estimate when an environmental compartment acts as an EPs source or a sink for a single con-

Two of the main topics of growing concern in analytical chemistry are the development of

cleanup applications; they have efficiently decomposed and removed a variety of pollutants promoting the generation of OH radicals using oxidation reactions with in situ active oxygen generated upon light irradiation. In water purification, photodegradation of contaminants in

There are some studies using electrocoagulation process to decompose EPs compounds. The process is an electrochemical introducing coagulants and removing suspended solids, colloidal material, and metals as well as other dissolved solids from water and wastewater eliminating pollutants, pesticides, and radionuclides. A direct current is applied, and one electrode

The environmental chemistry is the base for many treatment technologies of these pollutants, and the application of the adsorption process is one of the most used techniques. The results and comparison of different treatment technologies usually consider the initial concentration and the final concentration. The adsorbent materials are graphene oxide, clay mineral and biochar, nanocrystalline mineral, and arsenite using an enhanced coagulation process [6, 7]. The pharmaceuticals used iron chemical reduction reaction, and the advanced oxidation performed by ozone/UV also was used. The pharmaceuticals uses iron chemical reduction reaction, and the advanced oxidation performed by ozone /UV. The study of micropollutants biodegradation uses also a membrane.

The most common material used for EPs adsorption is the activated carbon (AC) with high porosity and surface area, and the use of AC shows the removal percentage higher than 90% for a wide variety of compounds bringing the residual concentration below the regulation limit. Other materials need more contact time for the same results. The advanced wastewater reclamation plant often uses the AC [5]. Many authors point out the high importance of the AC origin, depending on the initial crystalline structure of the biomass, the AC obtained from wood, vine, and olive waste, and coal showed the removal percentage always higher than 80% for antibiotics. There are some adsorbents used for pharmaceutical removal as biochar, clay minerals, zeolites, Fe-Mn-binary oxide, graphene oxide, alumina, nanoscale iron, molecularly imprinted

real water samples has become an important topic of research in the recent years.

is soluble into a solution which finally precipitates as oxides or hydroxides.

has emerged as a promising photocatalyst for environmental

EPs Antibiotics: Photodecomposition and Biocarbon Adsorption

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taminant or a multi-compartment system.

**2. EPs photodecomposition**

polymer, and carbon nanotubes [5, 8].

green water treatment. TiO2

The EPs monitoring and control are a huge problem, and the solution represents a significant challenge in sampling procedures and analytical techniques. The monitoring procedures do not cover all EPs with a potential concern being the highly known hazardous controlled, and the newly discovered contaminants as nanomaterials and microplastics are virtually analytically nonexistent. In the study, the EPs presence and toxicity are studied using bioindication; the most common organism is the *Gammarus pulex* as a model invertebrate from water and sediment.

The properties such as absorption behaviors of pharmaceuticals, for example, can vary vastly in different soil types on ionized and nonionized form, affecting the interaction of soil. Little information is available about the EPs dynamics in the water column, sediments, and the accumulation in the aquatic food chain and the loads from the agro-environment through diffuse pollution or from urban and industrial areas [3, 4].

The EPs decomposition products detection includes enantiomeric distribution of chiral compounds found in the environment, and their possible toxicological differences between enantiomers that are of concern. Such information for the risk assessment analysis is also considered [3].

Worldwide, the regulatory framework is under development to control the production and the discharge of the EPs into water resources, a complex set of regulations governing the production, commercialization, and emission to control the EPs presence in the environment and the drinking water (quality standards and monitoring specification). The European Union (EU) has a regulation plan to register, evaluate, authorize, and restrict the use of almost all EPs substances manufactured or imported to EU.

The agricultural activity is one of the most critical contributors to diffuse pollution in Europe, and such emissions are predicted to increase in the future. The agriculture activity is considered an essential business for regulating the chemical EPs use and emission discharge into the environment. Some research projects are under development, trying to treat, decompose, and remove those pollutants from the water resources.

The emerging pollutants are considered the potentially toxic chemicals present in low concentrations and many environmental compartments. They include pesticides, biocides, pharmaceuticals, industrial chemicals, and personal care products. The common entrance of these compounds in surface water resources is via untreated sewage discharge, the effluents of wastewater treatment plants (WWTPs), and from agricultural, urban, and street runoff. The organic pollutant water inputs usually occur continuously in low dosages or as peaks trigged by emission or runoff events. Such a behavior is particularly harmful to antibiotics environmental contamination, providing the optimized conditions for microorganism adaptation and increase in resistance.

The concept of chemical activity helps to understand the EPs environmental fate, distribution, quantification, and prediction of the ecological partitioning theory of the chemicals in aquatic systems as water column, sediment (mostly organic matter), and biota (lipids and proteins). It addresses single compound or mixtures reaching the equilibrium. The chemical activity relies on partition coefficients which are only available as experimental values. There are some models calculating partition coefficients from octanol–water systems (Kow-based models), and they were used for decades to estimate the concentration in different compartments.

Nowadays, the relationship of the polyparameters linear-free energy is used to calculate the partition coefficients of biological and nonbiological matrices including lipids and different proteins [4, 5]. The model helps to describe the diffusion and partitioning processes and estimate when an environmental compartment acts as an EPs source or a sink for a single contaminant or a multi-compartment system.
