Genotoxicity of water samples from an area of the Pampean region (Argentina) impacted by agricultural and livestock activities.

The aim of this study was to assess the genotoxic potential of surface waters located in a rural area in the north east of Buenos Aires province (Argentina) using the Allium cepa test. Water samples were collected at four sites located in a drainage channel and two sites on the Burgos stream that receives water from the channel, taking into account the sowing and harvesting months and rainfall periods. Analytical determinations revealed high total concentrations of Cd, Cu, Pb, and Zn (maximum values: 0.030, 0.252, 0.176, and 0.960 mg L-1, respectively), and concentrations of glyphosate and its metabolite aminomethylphosphonic acid (AMPA), with maximum values of 13.6 and 9.75 µg L-1, respectively. Statistically positive correlations were observed between the total metal concentrations and precipitation. No cytotoxicity (mitotic index MI) was observed in A. cepa. However, several water samples showed significant increases in micronucleus (MN) frequencies with respect to the controls. No correlations were observed between MN and the abiotic variables or precipitation. These results showed a state of deterioration in the water quality at the rural area studied in Buenos Aires province, and heavy metal contamination may contribute to the genotoxic activity. A. cepa was shown to be a useful tool for the detection of genotoxicity in water samples from areas with agricultural and livestock activities.

Toxicity and Genotoxicity of Three Antimicrobials Commonly Used in Veterinary Medicine.

The toxicity of chlortetracycline (CTC), oxytetracycline (OTC) and enrofloxacin (ENF) was tested on two green algal species: the international standard Pseudokirchneriella subcapitata and the native Argentine species Ankistrodesmus fusiformis. All three antibiotics inhibited the algal growth. The most sensitive species was P. subcapitata, for which the EC50 for CTC, OTC and ENF were 1.19 ± 0.53, 0.92 ± 0.30 and 5.18 ± 3.80 mg L-1, respectively. The EC50 for A. fusiformis, were 3.23 ± 0.53, 7.15 ± 2.69 and 10.6 ± 1.28 mg L-1, respectively. The genotoxicity of these veterinary antibiotics was also assessed using chromosome aberration (CA) and micronuclei (MN) induction in Allium cepa roots. Three concentrations were tested (0.1, 1 and 10 mg L-1). Only ENF at 1 and 10 mg L-1 showed any significant MN induction. These data revealed that CTC, OTC and ENF could cause toxicity on green algae, whereas ENF could cause genotoxicity on A. cepa plants.

Sewage pollution: genotoxicity assessment and phytoremediation of nutrients excess with Hydrocotyle ranunculoides.

The discharge of sewage effluents into low-order streams has negative effects on water quality. Macrophytes can be efficient in the treatment of this wastewater due to the removal of the main pollutants. The genotoxicity of sewage-polluted water discharging into La Choza stream was evaluated by testing with Allium cepa. Also, a phytoremediation assay with continuous recirculation of the residual water was conducted for 12 days. Three treatments were carried out. One treatment (Hr) was performed with a macrophyte (Hydrocotyle ranunculoides), and two treatments were conducted without macrophytes: with lighting (Ai) and without lighting (Ao). The wastewater was toxic according to all the evaluated indexes (mitotic index, frequency of chromosomal aberrations and micronucleus). High concentrations of ammonium, dissolved inorganic nitrogen (DIN), total (TP) and soluble reactive phosphorous (SRP) and indicators of faecal contamination were determined in the wastewater. The ammonium, DIN, SRP and TP loads at the end of the assay were significantly lower in the treatments with light (Hr and Ai). So, the nutrient removal was due to their absorption and adsorption by the periphyton and H. ranunculoides. Our results lead us to recommend the maintenance and planting of macrophytes in lowland streams subject to sewage pollution.

Toxicity and genotoxicity assessment in sediments from the Matanza-Riachuelo river basin (Argentina) under the influence of heavy metals and organic contaminants.

The aim of this study was to investigate the parameters of chemical extraction associated with the detection of toxicity and genotoxicity in sediment sample extracts. Quantitative analysis of metals and polycyclic aromatic hydrocarbons (PAHs), together with a battery of four bioassays, was performed in order to evaluate the extraction efficiency of inorganic and organic toxicants. The extracts were carried out using two inorganic solvents, two organic solvents and two extraction methodologies, making a total of five extracts. Two toxicity tests, the algal growth inhibition of Pseudokirchneriella subcapitata and the root elongation inhibition of Lactuca sativa, and two genotoxicity tests, the analysis of revertants of Salmonella typhimurium and the analysis of micronuclei and chromosomal aberrations in Allium cepa, were performed. According to the chemical analysis, the acidic solution extracted more heavy metal concentrations than distilled water, and dichloromethane extracted more but fewer concentrations of PAH compounds than methanol. Shaker extracts with distilled water were non-toxic to P. subcapitata, but were toxic to L. sativa. The acidic extracts were more toxic to P. subcapitata than to L. sativa. The methanolic organic extracts were more toxic to the alga than those obtained with dichloromethane. None of these extracts resulted toxic to L. sativa. Mutagenic effects were only detected in the organic dichloromethane extracts in the presence of metabolic activation. All the inorganic and organic extracts were genotoxic to A. cepa. This study showed that the implementation of different extraction methods together with a battery of bioassays could be suitable tools for detecting toxicity and genotoxicity in sediment samples.

Evaluación genotóxica de sedimentos de la cuenca Matanza-Riachuelo bajo la influence de distintos usos del suelo / Genotoxic evaluation of sludge from Matanza-Riachuelo basin under the influence of different uses of land

El Río Matanza-Riachuelo y sus afluentes atraviesan zonas con diferente grado de contaminación generada por las actividades agrícola-ganaderas, urbana e industrial. Los contaminantes que llegan al agua y son depositados en los sedimentos pueden ser liberados nuevamente al agua generando efectos tóxicos y/o genotóxicos sobre los organismos acuáticos. El objetivo de este trabajo fue analizar la genotoxicidad de muestras de sedimentos de la cuenca Matanza-Riachuelo obtenidas de zonas con diferentes usos del suelo. Se seleccionaron cuatro sitios de muestreo. Se utilizaron 2 métodos de extracción de contaminantes (agitación y sonicación), 2 solventes orgánicos (metanol y diclorometano) y 2 solventes inorgánicos (agua y solución ácida), obteniéndose un total de 5 extractos para cada muestra. Se realizaron mediciones de metales pesados e hidrocarburos aromáticos policíclicos (HAPs) mediante espectrofotometría de absorción atómica y CG/MS, respectivamente. La genotoxicidad se evaluó mediante el test de Ames con 2 cepas de Salmonella typhimurium (TA98 y TA100), con y sin fracción microsomal S9, y el test de Allium cepa. De los cuatro sitios estudiados, los sedimentos del Riachuelo mostraron mayores concentraciones de metales pesados y HAPs. Para el test de Ames, sólo los extractos obtenidos en diclorometano resultaron genotóxicos para la TA100 +S9 mix. Tanto los extractos inorgánicos como los orgánicos fueron citotóxicos y genotóxicos para A. cepa. Se observó una correlación negativa entre algunos compuestos HAPs y la frecuencia de micronúcleos, indicando la presencia de efectos antagónicos con otros compuestos genotóxicos. Los extractos con mayor efecto tóxico y genotóxico fueron los obtenidos con diclorometano y solución ácida. Este estudio mostró que los contaminantes orgánicos e inorgánicos extraídos de muestras de sedimento de la Cuenca Matanza-Riachuelo, con diferente grado de impacto, presentan un potencial riesgo tóxico y genotóxico para el ecosistema acuático.

The Matanza-Riachuelo River and its tributaries traverse areas with different degrees of contamination due to farming, urban and industrial activities. The pollutants entering the water are deposited in sediments, and can be released back into the water producing toxic and/or genotoxic effects on aquatic organisms. The aim of this study was to analyze the genotoxicity of sediment samples from the Matanza-Riachuelo Basin with different land uses. Four sampling sites according to the characteristics of land use were selected. Two methods of extraction (stirring and sonication), two organic solvents (methanol and dichloromethane) and two inorganic solvents (water and acid solution) were used, yielding a total of 5 extracts for each sample. Measurements of heavy metals and polycyclic aromatic hydrocarbons (PAHs) by atomic absorption spectrophotometry and GC/MS, respectively were performed. Genotoxicity was assessed using the Ames test with 2 strains of Salmonella typhimurium (TA98 and TA100) with and without S9 microsomal fraction, and the Allium cepa test. Taking into account the four sites, sediments from Riachuelo showed higher concentrations of heavy metals and PAHs. Only the dichloromethane extracts were genotoxic to the Ames test using the TA100 strain +S9 the mix. Both organic and inorganic extracts were cytotoxic and genotoxic to A. cepa. A negative correlation between some PAHs compounds and micronucleus frequency were observed, indicating the presence of antagonistic effects with other genotoxic compounds in samples. The extracts with high toxic and genotoxic effects were obtained with dichloromethane and acid solution. This study showed that organic and inorganic contaminants extracted from sediment samples from the Matanza-Riachuelo Basin, with varying degrees of impact, have potential toxic and genotoxic risk to the aquatic ecosystem.

Hospital effluent constitutes a source of vancomycin-resistant Enterococci / El efluente hospitalario como fuente de enterococos vancomicina resistentes

Objectives: Enterococci are intrinsically resistant to many commonly used antimicrobial agents. They are able to acquire resistance with relative ease and can spread these genes to other species. Enterococci resistant to antibiotics are associated with the use of these in clinical practice and also the spread of resistant clones in the world. The aim of this work was to compare the characteristics of the strains of vancomycin-resistant enterococci (VRE) isolated from municipal wastewater and hospital effluent. Methods: Samples were obtained from the effluent of the Hospital Universitario José de San Martín (Buenos Aires) and the municipal wastewater of the city of Buenos Aires. Results: The bacterial counts of VRE were greater in the hospital effluent, with an odds ratio of 36.4 (95% CI: 26.0-50.8; p<0.0001). The VRE isolated were mainly identified as E. faecium. The results indicate a high prevalence of enterococci resistant to the antibiotics tested. Conclusion: We may conclude that the effluents of hospitals constitute a source of VRE showing multiple resistance to antibiotics

Objetivos: Las especies de enterococos son intrínsecamente resistentes a varios antibióticos, adquieren resistencia con relativa facilidad, y difunden estos genes de resistencia a otras especies. La resistencia a los antibióticos en enterococos está asociada al uso de los mismos en la clínica médica y también a la diseminación de clones resistentes en el mundo. El objetivo de este trabajo fue comparar las características de las cepas de enterococos resistentes a vancomicina (ERV) aisladas en efluentes hospitalarios y aguas residuales urbanas. Métodos: Se obtuvieron muestras de los efluentes del Hospital Universitario José de San Martín (Buenos Aires) y muestras de aguas residuales urbanas de la ciudad de Buenos Aires. Resultados: Los recuentos de ERV fueron mayores en los efluentes hospitalarios, siendo la odds ratio 36.4 (IC95%: 26.0-50.8; p<0.0001). Los ERV aislados se identificaron principalmente como E. faecium. Los resultados indicaron una alta prevalencia de enterococos resistentes al resto de los antibióticos ensayados. Conclusión: Podemos concluir que los efluentes de los centros hospitalarios constituyen una fuente de enterococos de resistencia múltiple a antibióticos

Phytotoxicity and genotoxicity assessment of imazethapyr herbicide using a battery of bioassays.

The imazethapyr herbicide (formulation Verosil(®)) was evaluated for phytotoxicity and genotoxicity using a battery of bioassays: (1) the growth inhibition of the green alga Pseudokirchneriella subcapitata, (2) the root growth and germination of the higher plant Lactuca sativa, (3) the genetic damage using the Salmonella/microsome test, and (4) the aneugenic and clastogenic effects on Allium cepa. The Verosil(®) formulation was highly toxic to the non-target green alga (median effective concentration (EC50) = 1.05 ± 0.05 mg active ingredient (a.i.) L(-1)), and concentrations above 10 mg a.i. L(-1) inhibited root elongation in lettuce: relative growth index (RGI) between 0.28 ± 0.01 and 0.66 ± 0.10. No genotoxic effect was observed in S almonella typhimurium at 100 mg a.i. L(-1), either with or without the microsomal fraction. However, significant differences in the frequency of chromosomal aberrations in anaphases and telophases (bridges, chromosome fragments, and vagrants) were observed in A. cepa at concentrations between 0.01 and 1 mg a.i. L(-1) with respect to the control. The frequencies of micronuclei showed significant differences with respect to the control at concentrations between 0.001 and 0.1 mg a.i. L(-1). A very high mitotic index (MI = 93.8 ± 5.8) was observed associated with a high number of cells in the prophase stage at 100 mg a.i. L(-1), indicating cytotoxicity. These results showed that imazethapyr is toxic to the non-target populations in both aquatic and terrestrial ecosystems. This herbicide might also exert clastogenic and aneugenic mitotic damage in higher plants. Therefore, the imazethapyr formulation may constitute an environmental risk to plants.

Ecotoxicological and genotoxic evaluation of Buenos Aires city (Argentina) hospital wastewater.

Hospital wastewater (HWW) constitutes a potential risk to the ecosystems and human health due to the presence of toxic and genotoxic chemical compounds. In the present work we investigated toxicity and genotoxicity of wastewaters from the public hospital of Buenos Aires (Argentina). The effluent from the sewage treatment plant (STP) serving around 10 million inhabitants was also evaluated. The study was carried out between April and September 2012. Toxicity and genotoxicity assessment was performed using the green algae Pseudokirchneriella subcapitata and the Allium cepa test, respectively. Toxicity assay showed that 55% of the samples were toxic to the algae (%I of growth between 23.9 and 54.8). The A. cepa test showed that 40% of the samples were genotoxic. The analysis of chromosome aberrations (CA) and micronucleus (MN) showed no significant differences between days and significant differences between months. The sample from the STP was not genotoxic to A. cepa but toxic to the algae (%I = 41%), showing that sewage treatment was not totally effective. This study highlights the need for environmental control programs and the establishment of advanced and effective effluent treatment plants in the hospitals, which are merely dumping the wastewaters in the municipal sewerage system.

Evaluación ecotóxica y genotóxica de aguas residuales hospitalarias / Ecotoxicological and genotoxic evaluation of hospital wastewaters

Los líquidos residuales provenientes de hospitales constituyen un riesgo potencial para los ecosistemas y la salud humana debido a la presencia de compuestos tóxicos y genotóxicos. El objetivo de este trabajo fue analizar la toxicidad y la genotoxicidad de los efluentes provenientes del Hospital de Clínicas José de San Martín (Buenos Aires). Las muestras del efluente se tomaron durante los días y horarios de mayor actividad del hospital y se separaron en dos fracciones: acuosa y orgánica (extractos). Los ensayos de toxicidad se realizaron en la fracción acuosa utilizando dos especies de algas verdes: Pseudokirchneriella subcapitata y Chlorella vulgaris. La genotoxicidad se evaluó en las dos fracciones mediante el ensayo de Salmonella/ microsomas en ausencia y presencia de mezcla S9, utilizando las cepas TA98 y TA100. Veintinueve muestras de un total de 53 muestras analizadas resultaron tóxicas para P. subcapitata (entre 18 y 55 % de inhibición), mientras que sólo 8 muestras lo fueron para C. vulgaris (entre 21 y 50 % de inhibición). Ninguna de las muestras resultó genotóxica para Salmonella, ni en los extractos ni en las fracciones acuosas. De los tres ensayos utilizados, P. subcapitata fue el más sensible, siendo el ensayo más apropiado para el monitoreo de estos efluentes.

Wastewaters from hospitals constitute a potential risk to the ecosystems and human health due to the presence of toxic and genotoxic chemical compounds. The objective of this work was to analyze the toxicity and genotoxicity of wastewaters from the "Hospital de Clínicas José de San Martín" (Buenos Aires). Wastewater samples were obtained during the days and hours of major hospital activities and they were separated into two fractions: aqueous and organic (extracts). The toxicity assays were performed for the aqueous fraction using the green algae species: Pseudokirchneriella subcapitata and Chlorella vulgaris. Genotoxicity was assessed for the two fraction samples using the Salmonella/microsome assay in presence and in absence of S9 mix, with the strains TA98 and TA100. Twenty nine of the 53 total analyzed samples were toxic to P. subcapitata (between 18 and 55 % inhibition), whereas only 8 samples were toxic to C. vulgaris (between 21 and 50 % inhibition). None of the samples resulted genotoxic to Salmonella. Of the three tests used, P. subcapitata was the most sensible, resulting in the most suitable species to be used in hospital wastewaters monitoring.

Evaluación ecotóxica y genotóxica de aguas residuales hospitalarias / Ecotoxicological and genotoxic evaluation of hospital wastewaters

Los líquidos residuales provenientes de hospitales constituyen un riesgo potencial para los ecosistemas y la salud humana debido a la presencia de compuestos tóxicos y genotóxicos. El objetivo de este trabajo fue analizar la toxicidad y la genotoxicidad de los efluentes provenientes del Hospital de Clínicas José de San Martín (Buenos Aires). Las muestras del efluente se tomaron durante los días y horarios de mayor actividad del hospital y se separaron en dos fracciones: acuosa y orgánica (extractos). Los ensayos de toxicidad se realizaron en la fracción acuosa utilizando dos especies de algas verdes: Pseudokirchneriella subcapitata y Chlorella vulgaris. La genotoxicidad se evaluó en las dos fracciones mediante el ensayo de Salmonella/ microsomas en ausencia y presencia de mezcla S9, utilizando las cepas TA98 y TA100. Veintinueve muestras de un total de 53 muestras analizadas resultaron tóxicas para P. subcapitata (entre 18 y 55 % de inhibición), mientras que sólo 8 muestras lo fueron para C. vulgaris (entre 21 y 50 % de inhibición). Ninguna de las muestras resultó genotóxica para Salmonella, ni en los extractos ni en las fracciones acuosas. De los tres ensayos utilizados, P. subcapitata fue el más sensible, siendo el ensayo más apropiado para el monitoreo de estos efluentes.(AU)

Wastewaters from hospitals constitute a potential risk to the ecosystems and human health due to the presence of toxic and genotoxic chemical compounds. The objective of this work was to analyze the toxicity and genotoxicity of wastewaters from the "Hospital de Clínicas José de San Martín" (Buenos Aires). Wastewater samples were obtained during the days and hours of major hospital activities and they were separated into two fractions: aqueous and organic (extracts). The toxicity assays were performed for the aqueous fraction using the green algae species: Pseudokirchneriella subcapitata and Chlorella vulgaris. Genotoxicity was assessed for the two fraction samples using the Salmonella/microsome assay in presence and in absence of S9 mix, with the strains TA98 and TA100. Twenty nine of the 53 total analyzed samples were toxic to P. subcapitata (between 18 and 55 % inhibition), whereas only 8 samples were toxic to C. vulgaris (between 21 and 50 % inhibition). None of the samples resulted genotoxic to Salmonella. Of the three tests used, P. subcapitata was the most sensible, resulting in the most suitable species to be used in hospital wastewaters monitoring.(AU)

[Soil texture as a regulating factor of Escherichia coli adsorption in a Rolling Pampa basin (Argentina)]. / La textura del suelo como factor regulador de la adsorción de Escherichia coli en una cuenca de la Pampa Ondulada (Argentina).

Increase of bovine livestock rates in fragile areas of the Rolling Pampa entails a high risk of biological contamination. This biological contamination is regulated by edaphic variables such as texture, which control biological contaminants transport towards water bodies. In this work bacterial adsorption was correlated with individual particle sizes in 27 soils of a typical basin of the Rolling Pampa with slow centrifugation techniques. Bacterial adsorption values, using E. coli (ATCC 8739), ranged between 25.3 and 73.3% and significant correlation (R² = 0.6) was found between bacterial adsorption and clay content. This correlation was improved when particles smaller than 3 µm were considered (R² = 0.64) highlighting the capacity of very fine silt in adsorption mechanisms. Data obtained were compared with those proposed by Ling et al. (2002), finding similar slope but different intercept. This difference disappeared when a wild strain, isolated from bovine manures present in the basin, was used, since a bacterial adsorption increase of 48% was found.

La textura del suelo como factor regulador de la adsorción de Escherichia coli en una cuenca de la Pampa Ondulada (Argentina) / Soil texture as a regulating factor of Escherichia coli adsorption in a Rolling Pampa basin (Argentina)

El aumento de la carga animal vacuna en la Pampa Ondulada asociado a áreas frágiles supone un importante riesgo de contaminación biológica. Dicha contaminación está regulada por variables edáficas, como la textura, que controlan el transporte de contaminantes biológicos hacia los cuerpos de agua. En el presente trabajo se correlacionó la adsorción bacteriana del suelo con distintos tamaños de partículas individuales correspondientes a 27 suelos provenientes de una cuenca de la Pampa Ondulada. Para ello se utilizó una técnica de centrifugación lenta. Los valores de adsorción bacteriana, empleando en la determinación Escherichia coli ATCC 8739, variaron entre 25,3% y 73,3%, y el tamaño de partícula que mejor se correlacionó con esta propiedad fue el correspondiente a la fracción de arcillas (R² = 0,6). Esta correlación mejoró al considerar conjuntamente a todas las partículas menores de 3 µm (R² = 0,64), lo que resalta la capacidad de los limos muy finos en el fenómeno de adsorción. La curva de ajuste elaborada con los datos experimentales se comparó con la obtenida de acuerdo con el modelo propuesto por Ling et al. (2002). Se encontraron similitudes en la pendiente, no así en la ordenada al origen. Esta diferencia desapareció al emplear en la determinación una cepa autóctona aislada de deyecciones animales provenientes de la cuenca estudiada, dado que dicha cepa evidenció una adsorción 48% superior a la observada con la cepa de colección.

Increase of bovine livestock rates in fragile areas of the Rolling Pampa entails a high risk of biological contamination. This biological contamination is regulated by edaphic variables such as texture, which control biological contaminants transport towards water bodies. In this work bacterial adsorption was correlated with individual particle sizes in 27 soils of a typical basin of the Rolling Pampa with slow centrifugation techniques. Bacterial adsorption values, using E. coli (ATCC 8739), ranged between 25.3 and 73.3% and significant correlation (R² = 0.6) was found between bacterial adsorption and clay content. This correlation was improved when particles smaller than 3 µm were considered (R² = 0.64) highlighting the capacity of very fine silt in adsorption mechanisms. Data obtained were compared with those proposed by Ling et al. (2002), finding similar slope but different intercept. This difference disappeared when a wild strain, isolated from bovine manures present in the basin, was used, since a bacterial adsorption increase of 48% was found.

Genotoxicity of leachates from highly polluted lowland river sediments destined for disposal in landfill.

The Matanza-Riachuelo is one of the most polluted rivers of Latin America. The complex chemical mixture of pollutants discharged into the river is accumulated in the river sediments. In this paper, Matanza-Riachuelo river sediment composition and genotoxicity were tested in order to develop a cost-effective, environmentally sound option for disposal and management of contaminated dredged materials. Sampling was performed in a rural area, in a solid waste dumpsite and also in an urban and industrial area. The concentrations of total heavy metals increased from the upper basin to the lower basin. The Ames Salmonella typhimurium test and the Saccharomyces cerevisiae D7 test were performed using toxicity characteristic leachate procedure (TCLP) leachates. The concentrations of copper, lead, and chromium in the leachates exceeded the guide levels for the protection of aquatic life. Low concentrations of organic chlorinated compounds were detected in the leachates. Genotoxic profiles were obtained by testing TCLP leachates from polluted sediment samples with Salmonella typhimurium, Saccharomyces cerevisiae D7, and water sediment suspension with Allium cepa test. No mutagenicity effects on Ames test were observed. Gene conversion and mitotic reversion in Saccharomyces cerevisiae D7 and chromosome aberration in Allium cepa were induced by the sediment samples. Results obtained suggest that dredged sediments could be classified as genotoxic hazardous waste.

Impacto de las aguas residuales hospitalarias en el sistema de cloacas de la ciudad de Buenos Aires, Argentina. Toxicidad y genotoxicidad

El objetivo del trabajo fue determinar el aporte de carga tóxica y genotóxica al sistema cloacal urbano por los efluentes de hospital. Se utilizaron dos sistemas biológicos, el ensayo de Ames y el de Saccharomyces cerevisiae D7, observando toxicidad solo en los extractos puros y genotoxicidad en 4 de las 9 muestras analizadas. La genotoxicidad observada podría producir un impacto ambiental de importancia en el ecosistema y para la salud humana

Impacto de las aguas residuales hospitalarias en el sistema de cloacas de la ciudad de Buenos Aires, Argentina. Toxicidad y genotoxicidad

El objetivo del trabajo fue determinar el aporte de carga tóxica y genotóxica al sistema cloacal urbano por los efluentes de hospital. Se utilizaron dos sistemas biológicos, el ensayo de Ames y el de Saccharomyces cerevisiae D7, observando toxicidad solo en los extractos puros y genotoxicidad en 4 de las 9 muestras analizadas. La genotoxicidad observada podría producir un impacto ambiental de importancia en el ecosistema y para la salud humana

Impacto de las aguas residuales hospitalarias en el sistema de cloacas de la Ciudad Autonoma de Buenos Aires. Perfil microbiológico y resistencia a desinfectantes

El trabajo tiene como objetivo la caracterización microbiológica del efluente del Hospital de Clínicas General San Martin, Hospital Escuela de la Universidad de Buenos Aires. Para ello se determinó el número de bacterias heterotróficas, coliformes, Escherichia colli, enterococos. Pseudomonas sp. y Staphylococcus sp. en el efluente hospitalario y se evaluó la resistencia microbiana a los desinfectantes utilizados en el hospital

Impacto de las aguas residuales hospitalarias en el sistema de cloacas de la Ciudad Autonoma de Buenos Aires. Perfil microbiológico y resistencia a desinfectantes

El trabajo tiene como objetivo la caracterización microbiológica del efluente del Hospital de Clínicas General San Martin, Hospital Escuela de la Universidad de Buenos Aires. Para ello se determinó el número de bacterias heterotróficas, coliformes, Escherichia colli, enterococos. Pseudomonas sp. y Staphylococcus sp. en el efluente hospitalario y se evaluó la resistencia microbiana a los desinfectantes utilizados en el hospital

Comparación del efecto genotóxico de distintas aguas residuales

La legislación vigente en muchos países, incluso Argentina, exige que se controle la carga genotóxica de los efluentes peligrosos. El objetivo del presente trabajo fue demostrar la utilidad del ensayo de Ames para comparar la genotoxicidad de lo efluentes crudos correspondiente a las siguientes actividades: a)producción de colorantes; b)curtido al cromo de cueros; c)revelado fotográfico y d)laboratorio de análisis biológicos

Contaminación del aire en la Argentina: aspectos generales, legislación y situación de la Capital Federal y Provincia de Buenos Aires

Este libro es el primero de una serie en el que la Asociación Argentina Contra la Contaminación Ambiental (AACCA) dará un panorama actualizado de distintos aspectos de la contaminación. En la primera parte se da una caracterización de los principales contaminantes, sus efectos tóxicos para vegetales, animales y humanos y sus efectos sobre materiales. La segunda parte trata los aspectos relacionados con la legislación nacional e internacional. La tercera parte trata la situación actual de la Argentina

Contaminación del aire en la Argentina: aspectos generales, legislación y situación de la Capital Federal y Provincia de Buenos Aires

Este libro es el primero de una serie en el que la Asociación Argentina Contra la Contaminación Ambiental (AACCA) dará un panorama actualizado de distintos aspectos de la contaminación. En la primera parte se da una caracterización de los principales contaminantes, sus efectos tóxicos para vegetales, animales y humanos y sus efectos sobre materiales. La segunda parte trata los aspectos relacionados con la legislación nacional e internacional. La tercera parte trata la situación actual de la Argentina