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In recent years, there has been a growing demand for high-quality sunscreens that combine high efficacy with ecological characteristics. This trend has led to an increased use of triazine compounds, which represent an emerging class of UV filters. While it is well-established that sunscreens can have significant environmental impacts, there is limited data on the degradation of triazine UV filters, despite available information on their environmental persistence, particularly in relation to disinfection processes. This study investigates the chemical fate of ethylhexyl triazone (EHT) under chlorination conditions, typical of swimming pools. Twelve disinfection byproducts (DBPs) were isolated and fully identified using nuclear magnetic resonance and mass spectrometry, with three of these byproducts being identified for the first time. DBP1-DBP12 were isolated at relative percentages of 1.26, 9.68, 1.05, 0.42, 0.84, 3.37, 3.58, 1.89, 0.84, 1.47, 0.42, and 0.63. Additionally, a mechanism for their formation was proposed. The ecotoxicological assessment of EHT and of byproducts (DBP1-DBP4) was conducted using acute, sub-chronic or chronic toxicity tests in producers and primary consumers of the freshwater trophic chain. The organisms included the alga Raphidocelis subcapitata, the rotifer Brachionus calyciflorus, the crustacean anostracan Thamnocephalus platyurus and the benthic ostracod Heterocypris incongruens. EHT caused a lethal median concentration in rotifers, with values in the range of tens of mg/L. EHT, DBP1, and DBP4 exhibited sub-chronic effects in ostracods at concentrations in the μg/L range, with EC50s of 210, 9, 20 μg/L, respectively. Rotifers were slightly affected by DBP3 with a chronic EC50 of 200 μg/L. Algae were not affected by either EHT or byproducts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

In recent years, the antihypertensive drug Valsartan (VAL) has been detected in surface waters up to concentrations of 6300 ng/L, due to its high consumption and its mostly unchanged excretion. Moreover, wastewater treatment plants fail to completely mineralize/transform it, as evidenced by findings of up to 3800 ng/L in some effluents. In this paper, the possible degradation of VAL was evaluated through Fenton-like reaction with activation of peroxymonosulfate in the presence of Fe(II) under neutral conditions. Fourteen degradation byproducts were isolated and completely identified by both nuclear magnetic resonance and mass spectrometry, five of which were discovered for the first time, and a mechanism of their formation was proposed. Furthermore, the potential acute and chronic toxicity of valsartan and its byproducts in the aquatic environment were evaluated in key organisms of the freshwater trophic chain belonging to producers and consumers, the alga Raphidocelis subcapitata and the rotifer Brachionus calyciflorus, respectively. Acute effects occurred at concentrations in the order of tens/hundreds of mg/L, far from those of environmental concern. As regards chronic effects, algae were not particularly affected by the parent compound and its derivatives, while rotifers were less affected by derivatives (effective concentrations at units/tens of μg/L) compared to valsartan (effective concentrations at hundreds of ng/L)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

The photochemical behavior of etodolac was investigated under various irradiation conditions. Kinetic data were obtained after irradiation of 10(-4) M aqueous solutions by UVB, UVA and direct exposure to sunlight. The Xenon lamp irradiation was used in order to determine the photodegradation quantum yield under sun-simulated condition (ϕsun). The value was determined to be=0.10±0.01. In order to obtain photoproducts and for mechanistic purposes, experiments were carried out on more concentrated solutions by exposure to sunlight and to UVA and UVB lamps. The drug underwent photooxidative processes following an initial oxygen addition to the double bond of the five membered ring and was mainly converted into a spiro compound and a macrolactam. Ecotoxicity tests were performed on etodolac, its photostable spiro derivative and its sunlight irradiation mixture on two different aquatic trophic levels, plants (algae) and invertebrates (rotifers and crustaceans). Mutagenesis and genotoxicity were detected on bacterial strains. The results showed that only etodolac had long term effects on rotifers although at concentrations far from environmental detection values. A mutagenic and genotoxic potential was found for its derivative., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The aim of the present study was to investigate the in vitro estrogenic and the cytotoxic activity of six cytostatics (5-fluorouracil, capecitabine, cisplatin, doxorubicin, etoposide, and imatinib) belonging to the five classes of Anatomical Therapeutic Classification (ATC) detected in wastewater systems. The estrogenic activity was assessed by YES-assay on Saccharomyces cerevisiae-RMY326 and E-screen on MCF-7 cells. The cytotoxic activity was assessed by MTT Cell Proliferation Assay on the MCF-7 and the MDA-MB-231 cells. The results of estrogenic activity, detected by E-screen and expressed as EC50, showed a high potential of imatinib (10(-7) μM) followed by cisplatin and 5-fluorouracil. Capecitabine was poorly estrogenic while etoposide and doxorubicin EC50 values were not possible to determine. Cytotoxicity was found at concentrations far from those detected in effluents. The potential endocrine activity of the most active drugs could be associated with human and wildlife risk when considering their occurrence in the environment., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Caffeine is ubiquitous in surface and ground waters and it has been proposed as a marker of the anthropogenic pressure on the environment. Sewage treatment plants based on active sludges seem to be not very efficient in its complete removal from effluents while additional disinfection treatments by chlorination are able to do it. In a simulation of the chlorination step herein we report that caffeine is transformed in six by-products: 8-chlorocaffeine, 1,3-dimethyl-5-azabarbituric acid, N,N'-dimethylparabanic acid, N,N'-dimethyloxalamide, N-methylurea and N,N'-dimethylurea. The ecotoxicity of caffeine and identified compounds was evaluated on the rotifer Brachionus calyciflorus and the alga Pseudokirchneriella subcapitata to assess acute and chronic toxicity, while SOS Chromotest and Ames Test were used to detect the genotoxic potential of the investigated compounds. Moreover, we assessed the possible antigenotoxic effect of the selected compounds using SOS Chromotest after co-incubation with the standard genotoxin, 4-nitroquinoline 1-oxide. Chronic exposure to these compounds caused inhibition of growth population on the rotifer while the algae seemed to be unaffected. Results indicated that caffeine (1), N,N'-dimethyloxamide (4) and N,N'-dimethylparabanic acid (5) reduced β-galactosidase activity in comparison with positive control, both at 1 and 5mg/L of 4-NQNO with a good dose-response., (© 2013.)

Chlorination experiments on two drugs (sildenafil and tadalafil) were performed mimicking the conditions of a typical wastewater treatment process. The main transformation products were isolated by chromatographic techniques (Thin Layer Chromatography (TLC), Column Chromatography (CC), High Performance Liquid Chromatography (HPLC)) and fully characterized employing Nuclear Magnetic Resonance (NMR) and Mass Spectrometry (MS) analyses. The environmental effects of the parent compounds and transformation products were evaluated using an overall toxicity approach that considered aquatic acute and chronic toxicity on Brachionus calyciflorus and Ceriodaphnia dubia as well as mutagenesis and genotoxicity on bacterial strains. The results revealed that both parent drugs did not show high acute and chronic toxicity for the organisms utilized in the bioassays while, chronic exposure to chlorine derivatives caused inhibition of growth population on rotifers and crustaceans. A mutagenic potential was found for all the compounds investigated., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Nicotine, the main alkaloid of tobacco, is a non- prescription drug to which all members of a tobacco-smoking society are exposed either through direct smoke inhalation or through second-hand passive 'smoking'. Nicotine is also commercially available in some pharmaceutical products and is used worldwide as a botanical insecticide in agriculture. Nicotine dynamics in indoor and outdoor environments as well as the human excretions and the manufacturing process are responsible for its entry in the environment through municipal and industrial wastewater discharges. The presence of nicotine in surface and ground waters points out that it survives a conventional treatment process and persists in potable-water supplies. Complete removal of nicotine is instead reported when additional chlorination steps are used. In this paper a simulation of STP chlorination of nicotine and a genotoxic evaluation of its main degradation products are reported. Under laboratory conditions removal of nicotine seems not to be due to mineralization but to transformation in oxidized and chlorinated products. The by-products have been isolated after fractionation by diverse chromatographic procedures and their structures determined using mass spectrometry and (1)H and (13)C NMR spectroscopy. Preliminary genotoxic SOS Chromotests with Escherichia coli PQ37 evidence no toxicity of the products., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The occurrence of pharmaceuticals in the environment is of great concern and only few data are available about the adverse effects of such molecules and their derivatives on non-target aquatic organisms. This study was designed to assess the toxic potential of Naproxen, a nonsteroidal anti-inflammatory, Naproxen Na, its freely water soluble sodium salt and their photoproducts in the aquatic environment. Bioassays were performed on algae, rotifers and microcrustaceans to assess acute and chronic toxicity. Furthermore, possible genotoxic effects of photoderivatives were investigated using SOS chromotest and Ames fluctuation test. The results showed that photoproducts were more toxic than the parent compounds both for acute and chronic values, while genotoxic and mutagenic effects were not found. These findings suggested the opportunity to consider derivatives in ecotoxicology assessment of drugs.

The ecotoxicity of the following six antibiotics on aquatic organisms was investigated: Erythromycin, Oxytetracyclin, Sulfamethoxazole, Ofloxacin, Lincomycin and Clarithromycin. Bioassays were performed on bacteria, algae, rotifers, microcrustaceans and fish to assess acute and chronic toxicity, while SOS Chromotest and Ames test were used to detect the genotoxic potential of the investigated drugs. For risk assessment, the environmental impact was calculated by MEC/PNEC ratio using the available data from the literature regarding their occurrence in the aquatic environment and the toxicity data obtained from the bioassays performed. The ecotoxicological results showed that acute toxicity was in the order of mg/L while, for the chronic data the antibiotics were bioactive at concentrations in the order of microg/L, mainly for the algae. Drugs investigated were one or two order of magnitude less active against rotifers and crustaceans. Ofloxacin was the only genotoxic compound and Sulfamethoxazole, Ofloxacin and Lincomycin were mutagenic. As for environmental risk, the macrolides were found to be the most harmful for the aquatic environment.

The application of a battery of toxicity and genotoxicity tests on pore water in parallel and in combination with physico-chemical analyses and benthic macroinvertebrate community investigations is discussed as a tool to assess the environmental quality of the Volturno River in South Italy. Toxicity testing was performed on the rotifer Brachionus calyciflorus and the crustacean Daphnia magna. Genotoxicity was determined by the SOS chromotest and Mutatox system. The biotic index used for macroinvertebrates was the extended biotic index that was developed to verify if the observed benthic community accords with the expected one for an identical environment without anthropic contaminations. The physico-chemical characterization of the surface waters showed a declining trend from up-river to down-river for dissolved oxygen and conductivity. Also, chemical variables showed a worsening along the river axis showing an increase in ammonium, phosphates, sulfates, and heavy metals. The assessment of macro-invertebrates reflected the general ecological deterioration occurring to chemical as well as toxic and genotoxic pollution. Furthermore, benthic community composition and the sediment contamination of toxic and genotoxic substances were shown to be correlated. We concluded that investigations on pore water, integrated with benthic macroinvertebrate communities, could provide the basis for a robust monitoring of rivers.