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Occurrence and fate of CECs transformation products
Published in Manish Kumar, Sanjeeb Mohapatra, Kishor Acharya, Contaminants of Emerging Concerns and Reigning Removal Technologies, 2022
Han et al. (2020) studied the degradation of TC and oxytetracycline (OTC) using the photo-Fenton process. Degradation of TC and OTC yielded four and nine TPs, respectively. V. fischeri toxicity test showed that TC degradation produces less toxic TPs, while at the beginning, OTC degradation leads to higher toxicity; further, it yielded nontoxic TPs (Han et al., 2020). Chatzimpaloglou et al. (2021) studied the photocatalytic and photolytic degradation of antineoplastic drug irinotecan. A total of 19 TPs and 32 TPs were identified during the photolytic and photocatalytic processes, respectively. The toxicity of the parent compound was found to reduce drastically during the degradation process due to the formation of TPs that are not easily degraded (Chatzimpaloglou et al., 2021). Han et al. (2019) studied the toxicity of TPs formed due to the chloramination of CBZ, a widely used antiepileptic drug. From previous studies, around 12 TPs are formed during chloramination of CBZ. Three of the TPs exhibited cytotoxicity, chromosome damage, and greater DNA damage. TPs like 9 (10H)-acridone and acridine showed higher genotoxic or cytotoxic effects than the parent compound. These TPs are found to exhibit a greater toxic risk (Han et al., 2019).
Occurrence of Transformation Products of Pharmaceutical and Personal Care Products in the Aquatic Environment
Published in Leo M. L. Nollet, Dimitra A. Lambropoulou, Chromatographic Analysis of the Environment, 2017
Myrsini Papageorgiou, Eleni Evgenidou, Dimitra A. Lambropoulou
CBZ has been detected in influents, in effluents of WWTPs, and in other water matrices. After consumption, 70% is metabolized, leading to the formation of more than 30 compounds (Miao et al., 2005). The main metabolic pathway for CBZ is oxidation, leading to the formation of carbamazepine-10,11-epoxide (CBZ-Ep), which is a pharmacologically active compound with anticonvulsant properties. CBZ-Ep is further metabolized into 10,11-dihydro-10,11-trans-dihydroxycarbamazepine (DiOH-CBZ), which, in turn, leads to the formation of 9-hydroxy-methyl-10-carbamoylacridan. The DiOH-CBZ metabolite is not pharmaceutically active. Another metabolic route involves hydroxylation and production of the hydroxylated compounds 2-hydroxycarbamazepine (2-OH-CBZ) and 3-hydroxycarbamazepine (3-OH-CBZ), while 4-hydroxycarbamazepine (4-OH-CBZ) plays a minor role. Apart from these two major metabolic pathways, traces of acridine, acridone (ADON), iminostilbene, 2-hydroxy-iminostilbene, and 9-acridine-10-carboxaldehyde are formed in a minor pathway. Acridine has also been reported as genotoxic, mutagenic, and carcinogenic (Chiron et al., 2006).
Organic Materials for Green Electronics
Published in Neha Kanwar Rawat, Iuliana Stoica, A. K. Haghi, Green Polymer Chemistry and Composites, 2021
G. Vidya, Saravanan Subbiahraj, Praveen C. Ramamurthy
Głowacki et al. in 2011 informed that anthraquinones, carotenoids, and indigoids are giving charge carrier mobilities in the range of ~10−4 cm2 V−1·s−1 when applied in OFETs.47 Ambipolar indigoids show good semiconductor characteristics because of its long-range order, crystallinity, and very good dielectric features. The conducting polymers especially polythiophene, polypyrrole, polyaniline is used as organic electrodes but their biodegradability is not fully explored till now. But biocompatible metals such as Fe, Mg, and Zn are using in biomedical applications because the metals degrade in a particular biological environment.48 Instead of shellac, natural dielectric materials classified as two categories, first category consist of sugar-related small molecules such as fructose or glucose and the second category contain nucleobases such as adenine, guanine, cytosine, and thymine. These are using in OFETs because of their low dielectric losses, low leakage current, and also high breakdown strength.45,46 For the functionalization of DNA with a cationic surfactant leads to show solubility in polar solvents and also permits to form wet coated thin films. Therefore, it can be easily introduced as electron blocking layers in OLEDs and gate dielectrics in OFETs.49 Hongli Zhu et al. reported a cellulose-related transparent, biodegradable substrate joining either nano paper or a regenerated cellulose film (RCF) for highly flexible OLED applications and the performance should be stable in both the flat and bend direction.50 In 2013, Mihai Irimia-Vladu et al. reported as natural resin shellac applied in OFETs because of its biocompatibility, simple solution processing from ethanol solution, good dielectric breakdown fields, and low temperature crosslinking at 70 0C.51 In a photovoltaic cell, paper seems to be an ideal supporting material having its prize less than that of plastic and glass. The performance reported based on paper photovoltaic cell consists of open-circuit voltage having 50 V and a current of ~10 μA. Furthermore, the photovoltaic arrays should be twistingly bent and folded without loss of function.44 Quinacridone is a less costly natural derivative of acridone and it displays exciting photophysics properties such as highly sensitive toward light, already invented external quantum efficiency should be 10% in the single-layer OPV configuration.44 Organic-bioelectronics need more attention for the further development and industrialization because this field is now in its early stage and the main factors which are required to concentrate such as (1) examine the semiconducting properties of whole natural or nature-inspired materials, (2) understand their processability and film-forming properties, (3) examine electrochemical, optical and charge transport properties, (4) perform biodegradability studies and (5) use all the congregated knowledge to fabricate novel devices, etc.
Influence of UV dose on the UV/H2O2 process for the degradation of carbamazepine in wastewater
Published in Environmental Technology, 2019
Purnima Somathilake, John Albino Dominic, Gopal Achari, Cooper H. Langford, Joo-Hwa Tay
The extent of mineralization of CBZ was evaluated by measuring the residual TOC after the completion of each experiment. The extent of mineralization in case of UV photolysis was insignificant as more than 90% of TOC remained in solution after UV irradiation (0.7 J) of 8 h. UV photolysis is reported to result in the formation of acridine and acridone, which are significantly more recalcitrant than CBZ [15]. The degradation pathway of CBZ during UV photolysis present in natural waters and during water treatment has been reported in the literature [15,35,36]. Initially, hydroxylation of CBZ at the 10 position forms a radical intermediate resulting in 10,11-epoxycarbamazepine. Further, breaking of epoxide ring forms an unstable intermediate which suffers facile ring contraction to form 9-acridine-9-carboxaldehyde further decomposing into acridine [37]. Acridine is noted as an air and water pollutant with mutagenic and carcinogenic activities [38]. The formation of recalcitrant by-products of higher toxicity suggests that direct UV photolysis is not a suitable method for the treatment of CBZ.
Antiepileptic drugs in aquatic environments: Occurrence, toxicity, transformation mechanisms and fate
Published in Critical Reviews in Environmental Science and Technology, 2023
Quanzhen Liu, Long Wang, Xiong Xu, Saihong Yan, Jinmiao Zha, Donghong Wang, Dan Zhu
In addition to the parent compounds of AEDs, their metabolites/transformation products have also attracted extensive attention from researchers. There is evidence that more than 30 CBZ metabolites, including pharmacologically active or genotoxic compounds, have been identified in humans (Kaiser et al., 2014; Leclercq et al., 2009; Yin et al., 2017). And these metabolites can have more toxic than the parent CBZ. For example, Heye et al. investigated the chronic toxicity of 10,11-epoxy-10,11-dihydro-CBZ (CBZ-EP) on the nonbiting midge Chironomus riparius. The results showed that the metabolite CBZ-EP was significantly more toxic than the parent CBZ (Heye et al., 2016). Han et al. investigated the changes of the cytotoxicity and genotoxicity for CBZ treated by the processes of chlorination, chloramination and ozonation. The transformation products mixture after chlorination and chloramination processes caused DNA damage effects in SOS/umu test. Acridine, acridone, chlorinated acridone and aridine-9,10(4aH)-dicarbaldehyde were identified and predicted to be the DNA damaging agents. Furthermore, transformation products mixture after ozonation enhanced the cytotoxicity and the chromosome damage effects on CHO-K1 cells (Han et al., 2018). In the study of Li et al., thirteen transformation products of OXC under different water disinfection processes (ozonation, chlorination, and UV irradiation) were identified, including acridine with carcinogenic properties. An increasing acute toxicity was observed during UV irradiation probably because of the accumulation of acridine (Li et al., 2011; Yin et al., 2017). Also, gabapentin-lactam, as a transformation product during biological processes of GAB, were suspected to be more toxic than its parent, and lead to adverse impacts on the zebrafish (D. rerio) embryos (He et al., 2021).
Transformation of PPCPs in the environment: Review of knowledge and classification of pathways according to parent molecule structures
Published in Critical Reviews in Environmental Science and Technology, 2023
Kevin Bonnot, Pierre Benoit, Laure Mamy, Dominique Patureau
Only eight TPs of carbamazepine, which were identified in synthetic media, were also found in non-synthetic matrices: carbamazepine 10,11-epoxide (CBZ-EP), 2-hydroxycarbamazepine (2OH-CBZ), 3-hydroxycarbamazepine (3OH-CBZ), C14H9NO2 (TP223A), 10,11-Dhg-CBZ, acridone, 9-CA-acridine and acridine (Figures 3 and 4). Among them, CBZ-EP was the most frequently identified TP within three different matrices (soils, sediments and natural waters). It is pharmacologically active (Bertilsson & Tomson, 1986) and its presence in water bodies is undesirable (Miao & Metcalfe, 2003). In natural waters, the main observed TPs were CBZ-EP, 2OH-CBZ, and 3OH-CBZ, acridone and acridine (López-Serna et al., 2012) (Figure 3). Some other TPs were identified in drinking water following ozonation treatment (McDowell et al., 2005). In these conditions, the transformation pathways involved cleavage, oxygenation, hydration and rearrangement. In soils, Koba et al. (2016) evidenced a slow degradation of carbamazepine leading to six TPs including CBZ-EP and oxcarbazepine (OXC) found in low amounts (Figure 3). Nevertheless, carbamazepine TPs such as CBZ-EP can contribute to soil and water contamination (Paltiel et al., 2016). Finally, despite carbamazepine appeared to be recalcitrant in a water/sediment system (Löffler et al., 2005), CBZ-EP was detected in sediments (Li et al., 2014). In WWTPs and surface waters, five human metabolites (2OH-CBZ, 3OH-CBZ, CBZ-EP 10,11-dihydroxy-CBZ, 10-hydroxy-CBZ) of carbamazepine were found by screening (Miao & Metcalfe, 2003). These compounds are the same than TPs from biotransformation studies in synthetic media (Jelic et al., 2012; Kang et al., 2008). It could therefore be assumed that the known metabolites of carbamazepine can also be TPs in WWTPs and surface waters, especially because 10,11-dihydroxy-CBZ was found at a concentration three times higher than carbamazepine in all samples (Miao & Metcalfe, 2003).