Modulating effects of humic acids on genotoxicity induced by water disinfectants in Cyprinus carpio

The use of chlorinated disinfectants during drinking-water production has been shown to generate halogenated compounds as a result of interactions of humic acids with chlorine. Such chlorinated by-products have been shown to induce genotoxic effects and consumption of chlorinated drinking-water has been correlated with increased risk for cancer induction in human populations. The aim of this work was to test the potential genotoxic effects on circulating erythrocytes of the fish Cyprinus carpio exposed in vivo to well-waters disinfected with sodium hypochlorite (NaClO), chlorine dioxide (ClO2) or peracetic acid (CH3COO2H, PAA), in the absence or presence of standard humic acids (HA). The effects were measured by use of the micronucleus (MN) and the single-cell gel electrophoresis (Comet) assays at different sampling times after a 3-day exposure period. The exposure to chlorine disinfectants without the addition of HA produced a clear toxic effect. Significant cytogenetic damage (i.e. MN induction) was detected in fish populations exposed to both NaClO and ClO2 with humic acids. In the Comet assay, a significant decrease of DNA migration was observed in erythrocytes of specimens after exposure to NaClO-disinfected water without HA. No effects were observed in any other experimental condition. (c) 2005 Elsevier B.V. All rights reserved

Comet assay and micronucleus test in circulating erythrocytes of Cyprinus carpio specimens exposed in situ to lake waters treated with disinfectants for potabilization

The detection of a possible genotoxic effect of surface water treated with disinfectants for potabilization is the aim of the present work. The Comet assay and the micronucleus test were applied in circulating erythrocytes of Cyprinus carpio. Young specimens (20-30g) were exposed in experimental basins, built within the potabilization plant of Castiglione del Lago (Perugia, Italy). In this plant the water of the Trasimeno Lake is treated and disinfected for potabilization before it is distributed to the people in the net of drinkable water. A continuous flow of water at a constant rate was supplied to basins; the water was continuously treated at a constant concentration with one of the three tested disinfectants (sodium hypochlorite, peracetic acid and chloride dioxide), one control basin being supplied with untreated water. Three sampling campaigns were performed: October 2000, February 2001 and June 2001. Repeated blood samplings through intracardiac punctures allowed to follow the same fish populations after different exposure times: before introduction of the disinfectant, and 10 or 20 days afterwards. An additional blood sampling was performed 3h after addition of the disinfectant in other, simultaneously exposed, fish populations. Genotoxic damage was shown in fish exposed to water disinfected with sodium hypochlorite and chloride dioxide. The Comet assay showed an immediate response, i.e. DNA damage that was induced directly in circulating erythrocytes, whereas micronuclei reached their highest frequencies at later sampling times, when a genotoxic damage in stem cells of the cephalic kidney is expressed in circulating erythrocytes. The quality of the untreated surface water seems to be the most important parameter for the long-term DNA damage in circulating erythrocytes. © 2003 Elsevier B.V. All rights reserved

Perturbation of cytochrome P450, generation of oxidative stress and induction of DNA damage in Cyprinus carpio exposed in situ to potable surface water

Epidemiological evidence suggests a link between consumption of chlorinated drinking water and various cancers. Chlorination of water rich in organic chemicals produces carcinogenic organochlorine by-products (OBPs) such as trihalomethanes and haloacetic acids. Since the discovery of the first OBP in the 1970s, there have been several investigations designed to determine the biological effects of single chemicals or small artificial OBP combinations. However, there is still insufficient information regarding the general biological response to these compounds, and further studies are still needed to evaluate their potential genotoxic effects. In the current study, we evaluated the effect of three drinking water disinfectants on the activity of cytochrome P450 (CYP)-linked metabolizing enzymes and on the generation of oxidative stress in the livers of male and female Cyprinus carpio fish (carp). The fish were exposed in situ for up 20 days to surface water obtained from the Trasmene lake in Italy. The water was treated with 1-2 mg/L of either sodium hypochlorite (NaClO) or chlorine dioxide (ClO2) as traditional disinfectants or with a relatively new disinfectant product, peracetic acid (PAA). Micronucleus (MN) frequencies in circulating erythrocytes from the fish were also analysed as a biomarker of genotoxic effect. In the CYP-linked enzyme assays, a significant induction (up to a 57-fold increase in the deethylation of ethoxyresorufin with PAA treatment) and a notable inactivation (up to almost a 90% loss in hydroxylation of p-nitrophenol with all disinfectants, and of testosterome 2 beta-hydroxylation with NaClO) was observed in subcellular liver preparations from exposed fish. Using the electron paramagnetic resonance (EPR) spectroscopy radical-probe technique, we also observed that CYP-modulation was associated with the production of reactive oxygen species (ROS). In addition, we found a significant increase in MN frequency in circulating erythrocytes after 10 days of exposure of fish to water treated with ClO2, while a non-significant six-fold increase in MN frequency was observed with NaClO, but not with PAA. Our data suggest that the use of ClO2 and NaClO to disinfect drinking water could generate harmful OBP mixtures that are able to perturb CYP-mediated reactions, generate oxidative stress and induce genetic damage. These data may provide a mechanistic explanation for epidemiological studies linking consumption of chlorinated drinking water to increased risk of urinary, gastrointestinal and bladder cancers. (c) 2006 Elsevier B.V. All rights reserved

Comparative pharmacokinetics of a long-acting amoxicillin formulation following its subcutaneous and intramuscular administration to dogs

The influence of the route of administration on the amoxicillin pharmacokinetics in dogs was\ninvestigated following the subcutaneous or intramuscular administration of 15 mg/kg amoxicillin\nformulated as a long-acting aqueous suspension. Serial blood samples were collected at predetermined\ntimes. Pharmacokinetic parameters were calculated from the disposition curves for both routes for\neach animal. Significant differences were observed for the parameters area under the curve (73.8\n± 13.1 mg.h/ml versus 88.3 ± 17.0 mg.h/ml) and mean residence time (6.9 ± 2.8 h versus 10.3 ±\n6.1 h) following the intramuscular and subcutaneous injections, respectively. The subcutaneous\nadministration exhibited higher depot effect than the intramuscular administration. No significant\ndifferences were observed for the time above the minimun inhibitory concentrations for bacteria\nof low (4 mg/ml) and high (0.250 mg/ml) amoxicillin sensitivity. Our data suggest that the tested\nformulation can be used with a prolonged interval of 48 h for high sensitivity bacteria, and that\nboth routes of administration provide similar kinetic profiles and thus, similar clinical outcomes.Fil: Porta, N. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Cátedra de Farmacología; ArgentinaFil: Prados, A.P. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Cátedra de Farmacología; ArgentinaFil: Kreil, V. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Cátedra de Farmacología; ArgentinaFil: Tarragona, L. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Cátedra de Farmacología; ArgentinaFil: Monfrinotti, A. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Cátedra de Farmacología; ArgentinaFil: Rebuelto, M. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Cátedra de Farmacología; ArgentinaSe investigó la influencia de la vía de administración en la farmacocinética de la amoxicilina en caninos,\nluego de la administración por las vías subcutánea e intramuscular de 15 mg/kg de amoxicilina\nformulada como una suspensión acuosa de larga acción. Se tomaron muestras de sangre en tiempos\npredeterminados, y se calcularon los parámetros farmacocinéticos de las curvas de disposición para\ncada animal y para cada vía de administración. Se observaron diferencias significativas para los\nparámetros área bajo la curva (73.8 ± 13.1 mg.h/ml versus 88.3 ± 17.0 mg.h/ml) y tiempo medio\nde residencia (6.9 ± 2.8 h versus 10.3 ± 6.1 h) luego de las inyecciones intramuscular y subcutánea,\nrespectivamente. La administración subcutánea mostró un mayor efecto depot que la intramuscular.\nNo se observaron diferencias significativas para el tiempo sobre la concentración inhibitoria mínima\npara bacterias de baja (4 mg/ml) y alta (0.250 mg/ml) susceptibilidad a la amoxicilina. Nuestros datos\nsugieren que la formulación probada puede ser utilizada con un intervalo posológico prolongado de\n48 h para bacterias muy susceptibles, y que ambas vías de administración proveen perfiles cinéticos\nsimilares, y por ende, similares resultados clínicos. \

The rapid spread of SARS-COV-2 Omicron variant in Italy reflected early through wastewater surveillance

The SARS-CoV-2 Omicron variant emerged in South Africa in November 2021, and has later been identified worldwide, raising serious concerns. A real-time RT-PCR assay was designed for the rapid screening of the Omicron variant, targeting characteristic mutations of the spike gene. The assay was used to test 737 sewage samples collected throughout Italy (19/21 Regions) between 11 November and 25 December 2021, with the aim of assessing the spread of the Omicron variant in the country. Positive samples were also tested with a real-time RT-PCR developed by the European Commission, Joint Research Centre (JRC), and through nested RT-PCR followed by Sanger sequencing. Overall, 115 samples tested positive for Omicron SARS-CoV-2 variant. The first occurrence was detected on 7 December, in Veneto, North Italy. Later on, the variant spread extremely fast in three weeks, with prevalence of positive wastewater samples rising from 1.0% (1/104 samples) in the week 5–11 December, to 17.5% (25/143 samples) in the week 12–18, to 65.9% (89/135 samples) in the week 19–25, in line with the increase in cases of infection with the Omicron variant observed during December in Italy. Similarly, the number of Regions/Autonomous Provinces in which the variant was detected increased from one in the first week, to 11 in the second, and to 17 in the last one. The presence of the Omicron variant was confirmed by the JRC real-time RT-PCR in 79.1% (91/115) of the positive samples, and by Sanger sequencing in 66% (64/97) of PCR amplicons. In conclusion, we designed an RT-qPCR assay capable to detect the Omicron variant, which can be successfully used for the purpose of wastewater-based epidemiology. We also described the history of the introduction and diffusion of the Omicron variant in the Italian population and territory, confirming the effectiveness of sewage monitoring as a powerful surveillance tool

The rapid spread of SARS-COV-2 Omicron variant in Italy reflected early through wastewater surveillance

The SARS-CoV-2 Omicron variant emerged in South Africa in November 2021, and has later been identified worldwide, raising serious concerns. A real-time RT-PCR assay was designed for the rapid screening of the Omicron variant, targeting characteristic mutations of the spike gene. The assay was used to test 737 sewage samples collected throughout Italy (19/21 Regions) between 11 November and 25 December 2021, with the aim of assessing the spread of the Omicron variant in the country. Positive samples were also tested with a real-time RT-PCR developed by the European Commission, Joint Research Centre (JRC), and through nested RT-PCR followed by Sanger sequencing. Overall, 115 samples tested positive for Omicron SARS-CoV-2 variant. The first occurrence was detected on 7 December, in Veneto, North Italy. Later on, the variant spread extremely fast in three weeks, with prevalence of positive wastewater samples rising from 1.0% (1/104 samples) in the week 5–11 December, to 17.5% (25/143 samples) in the week 12–18, to 65.9% (89/135 samples) in the week 19–25, in line with the increase in cases of infection with the Omicron variant observed during December in Italy. Similarly, the number of Regions/Autonomous Provinces in which the variant was detected increased fromone in the first week, to 11 in the second, and to 17 in the last one. The presence of the Omicron variant was confirmed by the JRC real-time RT-PCR in 79.1% (91/115) of the positive samples, and by Sanger sequencing in 66% (64/97) of PCR amplicons

The rapid spread of SARS-COV-2 Omicron variant in Italy reflected early through wastewater surveillance

The SARS-CoV-2 Omicron variant emerged in South Africa in November 2021, and has later been identified worldwide, raising serious concerns. A real-time RT-PCR assay was designed for the rapid screening of the Omicron variant, targeting characteristic mutations of the spike gene. The assay was used to test 737 sewage samples collected throughout Italy (19/21 Regions) between 11 November and 25 December 2021, with the aim of assessing the spread of the Omicron variant in the country. Positive samples were also tested with a real-time RT-PCR developed by the European Commission, Joint Research Centre (JRC), and through nested RT-PCR followed by Sanger sequencing. Overall, 115 samples tested positive for Omicron SARS-CoV-2 variant. The first occurrence was detected on 7 December, in Veneto, North Italy. Later on, the variant spread extremely fast in three weeks, with prevalence of positive wastewater samples rising from 1.0% (1/104 samples) in the week 5-11 December, to 17.5% (25/143 samples) in the week 12-18, to 65.9% (89/135 samples) in the week 19-25, in line with the increase in cases of infection with the Omicron variant observed during December in Italy. Similarly, the number of Regions/Autonomous Provinces in which the variant was detected increased from one in the first week, to 11 in the second, and to 17 in the last one. The presence of the Omicron variant was confirmed by the JRC real-time RT-PCR in 79.1% (91/115) of the positive samples, and by Sanger sequencing in 66% (64/97) of PCR amplicons. In conclusion, we designed an RT-qPCR assay capable to detect the Omicron variant, which can be successfully used for the purpose of wastewater-based epidemiology. We also described the history of the introduction and diffusion of the Omicron variant in the Italian population and territory, confirming the effectiveness of sewage monitoring as a powerful surveillance tool

Performance of different biotic indices and sampling methods in assessing water quality in the lowland stretch of the Tiber River

The lowland stretches of rivers are usually the ones where a macroinvertebrate species collection is more difficult to obtain because of the depth and turbidity of the water. Since the choice of the index and of the specific sampling technique is critical for the final result, there is a strong interest into setting up reliable methods for assessing the biological water quality. The aim of this paper is to elucidate the performances of four biotic indices and the influence of four sampling methods on the water quality assessment of a deep and turbid stretch of a river. We collected macroinvertebrates seasonally at 10 sampling sites along the final stretch of the Tiber River using four sampling methods (including hand net, wood and plastic artificial substrates). At the same time, chemical, physical, and bacteriological variables were recorded monthly along the same river stretch. Considering those variables, sampling sites were grouped into three clusters with different water quality, using the chronological clustering method. The same result was obtained from macroinvertebrate data using the same method. We then examined the ability of four biotic indices widely used in Italy to discriminate between the three clusters. The indices are: BMWP' (British Monitoring Working Party, modified for Spain), ASPT' (Average Score Per Taxon, modified for Spain), EBI (Extended Biotic Index) and IBE (Indice Biotico Esteso). BMWP' and ASPT' showed the best results. BMWP' and ASPT' scores - but not those of EBI and IBE - were sensitive to the different sampling methods utilised. We concluded that in this type of river stretch, BMWP' and ASPT' could be more useful than EBI and IBE although the relative efficiency of the chosen sampling method should be taken into account

Effet de differentes methodes d'echantillonnage sur les valeurs d'indices biotiques de la qualite de l'eau du cours inferieur d'un fleuve mediterraneen : Le Tibre

This paper aims to test the performance of two different biotic indices and the effect of four different sampling methods in assessing the water quality of the final tract of the River Tiber. One sampling methods involves use of a hand net for 3 minutes, the others use articial substrata left in water for all the study period. Our results showed a different performance of the two biotic indices and a significant effect of the sampling method on scores of the biotic indices

Effect of different sampling methods on the biotic indices values of the water quality in the lower part of the mediterranean River Tiber

This paper aims to test the performance of two different biotic indices and the effect of four different sampling methods in assessing the water quality of the final tract of the River Tiber. One sampling methods involves use of a hand net for 3 minutes, the others use articial substrata left in water for all the study period. Our results showed a different performance of the two biotic indices and a significant effect of the sampling method on scores of the biotic indices