Atrazine behavior in an agricultural soil: adsorption–desorption, leaching, and bioaugmentation with Arthrobacter sp. strain AAC22

Purpose: To evaluate atrazine behavior in an agricultural soil (adsorption–desorption, leaching) and the effects of bioaugmentation with the Arthrobacter sp. strain AAC22, as a soil remediating strategy. Material and methods: An agricultural soil with a history of atrazine application was used. Equilibrium batch experiments allowed the investigation of the adsorption–desorption of atrazine at different soil depths, while the atrazine leaching potential was assessed using disturbed soil columns. Arthrobacter sp. strain AAC22 was selected for bioaugmentation, to remove atrazine in soil microcosms. Removal efficiency was determined by a bioassay with oat seeds. Results and discussion: Adsorption and desorption isotherms of atrazine at different soil depths were well described by the Freundlich equation (R2 > 0.99 and R2 > 0.98, respectively). The Freundlich constant (Kf) and desorption coefficient (Kfd1–3) decreased and increased, respectively, as soil depth increased. The Kf and Kfd1–3 values were correlated positively to organic carbon (r = 0.97) and negatively to pH (r = − 0.93). In this soil, 70.2% of atrazine applied (2.5 kg ha−1) was recovered in the leachate and 7.6% remained in the soil column. The higher atrazine concentration leached can be explained by the negative hysteresis of adsorption–desorption in this soil. Bioaugmentation with AAC22 enhanced atrazine removal being nearly 70% after 2 days of treatment, and it was almost complete (> 99%) after 8 days. A bioassay demonstrated that bioaugmentation was successful and toxic by-products were not detected. Conclusion: The adsorption–desorption and leaching experiments demonstrated the high mobility of the atrazine in the study soil. The bioaugmentation using the AAC22 strain is an effective strategy for atrazine removal in polluted soils.Fil: Urseler, Noelia Luján. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto Multidisciplinario de Investigacion y Transferencia Agroalimentaria y Biotecnologica. - Universidad Nacional de Villa Maria. Instituto Multidisciplinario de Investigacion y Transferencia Agroalimentaria y Biotecnologica.; ArgentinaFil: Bachetti, Romina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto Multidisciplinario de Investigacion y Transferencia Agroalimentaria y Biotecnologica. - Universidad Nacional de Villa Maria. Instituto Multidisciplinario de Investigacion y Transferencia Agroalimentaria y Biotecnologica.; ArgentinaFil: Morgante, Verónica. Universidad Tecnologica Metropolitana (utem); . Universidad Bernardo O’Higgins; ChileFil: Agostini, Elizabeth. Universidad Nacional de Rio Cuarto. Facultad de Cs.exactas Fisicoquimicas y Naturales. Instituto de Biotecnologia Ambiental y Salud. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto de Biotecnologia Ambiental y Salud.; ArgentinaFil: Morgante, Carolina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto Multidisciplinario de Investigacion y Transferencia Agroalimentaria y Biotecnologica. - Universidad Nacional de Villa Maria. Instituto Multidisciplinario de Investigacion y Transferencia Agroalimentaria y Biotecnologica.; Argentin

Microbiological quality and uses of groundwater in the agricultural farms in the central-south area of Córdoba, Argentina

La intensificación de los sistemas productivos (agrícolas o ganaderos) ha provocado una alteración en la calidad del agua subterránea debido, entre otras causas, a la introducción de microorganismos contaminantes. La calidad microbiológica del agua debe considerarse como un parámetro elemental para definir su aptitud para diferentes usos: consumo de la población rural, consumo del ganado bovino o limpieza de instalaciones de ordeñe. Los objetivos de este estudio fueron: (1) conocer la calidad microbiológica del agua subterránea en establecimientos agropecuarios para definir aptitudes de uso y (2) evaluar la relación entre el uso del suelo y la calidad del agua subterránea de la región. Se realizaron análisis microbiológicos utilizando como indicadores: i) recuento de bacterias aerobias mesófilas, ii) detección de coliformes totales y fecales, y iii) presencia de Escherichia coli y Pseudomonas aeruginosa en muestras de agua obtenidas de perforaciones de establecimientos agrícolas (EA; n = 28) o ganaderos/lecheros (EG; n = 34) ubicados en la región centro-sur de la provincia de Córdoba, Argentina. En el 58 % de las muestras analizadas (n = 62) se detectó la presencia de al menos un indicador de contaminación que supera los parámetros para consumo humano o higiene de instalaciones de ordeñe. El 12 % de los EG poseen agua de calidad deficiente para el consumo del ganado bovino. Mediante análisis bivariados se encontró una escasa asociación entre el uso del suelo y la calidad microbiológica del agua, por lo que el origen de la contaminación observada responde a múltiples factores que inciden en la región.The productive systems intensification (agricultural or livestock) has caused groundwater shifts mainly due to the introduction of exogenous and contaminating microorganisms. The microbial quality of water must be considered as an essential parameter when defining the suitability of the groundwater for animals or rural human consumption, as well as for cleaning the facilities of the dairy. In this study, the objectives were: (1) to determine the microbiological quality of the groundwater in agricultural or livestock farms and, (2) to establish in the studied area the relationship between the land use and groundwater quality. The microbial analyses were performed using several indicators such as: i) aerobic mesophilic bacteria counts, ii) total and fecal coliforms count, and iii) detection of Escherichia coli and Pseudomonas aeruginosa in groundwater samples obtained from agricultural farms (EA; n = 28) or livestock/dairy farms (EG; n = 34) located in south-central area of Córdoba province, Argentina. At least one microbial indicator over the acceptable limit for human drink or for cleaning dairy farm facilities was detected in the 58 % of studied samples (n = 62). The 12 % of the EG demonstrated to have deficient water quality for animal consumption. By bivariate statistical analysis, a scarce relationship was observed between land uses and microbiological water quality indicating that bacterial contamination source is unspecific and probably due to intrinsic factors of the area.Fil: Urseler, Noelia Luján. Universidad Nacional de Villa María. Instituto Académico Pedagógico de Ciencias Básicas y Aplicadas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Bachetti, Romina. Universidad Nacional de Villa María. Instituto Académico Pedagógico de Ciencias Básicas y Aplicadas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Damilano, Gabriela. Universidad Nacional de Río Cuarto. Facultad de Ciencias Humanas; ArgentinaFil: Morgante, Verónica M.. Universidad Tecnologica Metropolitana (utem);Fil: Ingaramo, Rosa Natalia. Universidad Nacional de Villa María. Instituto Académico Pedagógico de Ciencias Básicas y Aplicadas; ArgentinaFil: Saino, Veronica. Universidad Nacional de Villa María. Instituto Académico Pedagógico de Ciencias Básicas y Aplicadas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Morgante, Carolina. Universidad Nacional de Villa María. Instituto Académico Pedagógico de Ciencias Básicas y Aplicadas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentin

Bioremediation strategies to mitigate the impact of Atrazine on the environment: Recent advances and prospects

Atrazine is an s-triazine herbicide widely used for the control of weeds, primarily in corn, sorghum and sugarcane crops. It is relatively persistent in the environment, moderately soluble in water and toxic to different organisms and humans. Its mobility through soil by leaching and runoff events frequently lead to contamination of sediments and water resources. Thus, atrazine has become a compound of public concern because it is frequently detected in surface, groundwater and rainfall samples in quantities exceeding the limit values set by regulatory agencies (the EU and the USA) for drinking water. In addition, several studies have shown its impact on the ecosystem and human health. For this reason, bioremediation strategies have been described to allow the removal of atrazine and avoid its dispersion in the environment. This chapter provides information on the behaviour and impact of atrazine in soil, aquatic ecosystems and non-target organisms and summarised current knowledge about bioremediation strategies for the clean-up of sites polluted with this herbicide. Recently, material-microbial-integrated technologies have been investigated in order to degrade atrazine, which will be also described. Finally, the bioremediation strategies are evaluated under laboratory and field conditions. Future advances related to atrazine degradation need to focus on an efficient removal and low environmental impact.Fil: Urseler, Noelia Luján. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto Multidisciplinario de Investigacion y Transferencia Agroalimentaria y Biotecnologica. - Universidad Nacional de Villa Maria. Instituto Multidisciplinario de Investigacion y Transferencia Agroalimentaria y Biotecnologica.; ArgentinaFil: Bachetti, Romina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto Multidisciplinario de Investigacion y Transferencia Agroalimentaria y Biotecnologica. - Universidad Nacional de Villa Maria. Instituto Multidisciplinario de Investigacion y Transferencia Agroalimentaria y Biotecnologica.; ArgentinaFil: Morgante, Carolina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto Multidisciplinario de Investigacion y Transferencia Agroalimentaria y Biotecnologica. - Universidad Nacional de Villa Maria. Instituto Multidisciplinario de Investigacion y Transferencia Agroalimentaria y Biotecnologica.; ArgentinaFil: Agostini, Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Biotecnología Ambiental y Salud; Argentin

Atrazine pollution in groundwater and raw bovine milk: Water quality, bioaccumulation and human risk assessment

Atrazine herbicide can bioaccumulate over time and thus affect humans for generations to come. However, scarce studies have evaluated its bioaccumulation potential in bovine milk, a nutritional staple for children and the elderly both domestically and internationally. This study aimed to determine its concentration in groundwater and bovine milk, as well as the risks it is likely to pose for human health. Eighteen dairy farms in the Pampean plain of Argentina were analyzed. A strong correlation was found between the chemical composition and the geomorphological characteristics of the plain. In addition, increased salinity was observed in the groundwater at greater distances from the aquifer's recharge area. Atrazine was quantified in 50 % of the groundwater samples (at values ranging from 0.07 to 1.40 μg/L), and in 89 % of the bovine milk samples (from 2.51 to 20.97 μg/L). Moreover, atrazine levels in 44.4 % of the groundwater samples and 11.1 % of the bovine milk samples (n = 18) exceeded the limits internationally established as safe for human consumption. The hazard quotient (HQ) values of the compound were negligible for children and adults, both in groundwater (child = 9.7E-4, adult = 4.5E-4) and in milk (child = 1.0E-2, adult = 1.6E-3). The estimated cancer risk (CR) values need further evaluation (child = 7.8E-6, adult = 3.6E-6 in groundwater; child = 6.6E-5, adult = 1.3E-5 in milk). In both types of samples, the HQ and CR of residual atrazine were higher for children than for adults. Nevertheless, bioaccumulation factors suggest that dairy cows have a moderate capacity to incorporate atrazine from abiotic matrices. This is the first report on residual atrazine in bovine milk in Argentina. The results presented here indicate that the status of atrazine contamination in the area should continue to be monitored in order to assess its long-term impact on public health.Fil: Urseler, Noelia Luján. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Investigación y Transferencia Agroalimentaria y Biotecnológica - Universidad Nacional de Villa María. Instituto Multidisciplinario de Investigación y Transferencia Agroalimentaria y Biotecnológica; ArgentinaFil: Bachetti, Romina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Investigación y Transferencia Agroalimentaria y Biotecnológica - Universidad Nacional de Villa María. Instituto Multidisciplinario de Investigación y Transferencia Agroalimentaria y Biotecnológica; ArgentinaFil: Biolé, Fernanda Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Investigación y Transferencia Agroalimentaria y Biotecnológica - Universidad Nacional de Villa María. Instituto Multidisciplinario de Investigación y Transferencia Agroalimentaria y Biotecnológica; ArgentinaFil: Morgante, Verónica. Universidad Bernardo O'higgins; ChileFil: Morgante, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Investigación y Transferencia Agroalimentaria y Biotecnológica - Universidad Nacional de Villa María. Instituto Multidisciplinario de Investigación y Transferencia Agroalimentaria y Biotecnológica; Argentin

Monitoring of Atrazine Pollution and its Spatial-Seasonal Variation on Surface Water Sources of an Agricultural River Basin

Surface water sources are greatly impacted in areas with major agricultural land use. The atrazine quantification in surface waters as well as the spatial-temporal patterns of this herbicide was studied to detect pollution hotspots and to understand the putative factors responsible of its occurrence at the Ctalamochita river basin. The samples were collected on the aeolian fluvial plain of the river basin during five consecutive years. The results showed the high ubiquity of this compound and several sites with hazardous concentration (exceeding 0.1 µg/L international guidelines). The frequencies of quantification range from 67 to 100% in spring and 33%–67% in autumn. The atrazine content in surface water increased during the warm-rainy season, as consequence of atrazine application events (coinciding to the prevalent crop type). Overall, the study highlights the factors that could have favored atrazine pollution in the river basin such as land use, transport by runoff processes and atmospheric deposition.Fil: Bachetti, Romina. Universidad Nacional de Villa María. Instituto Académico Pedagógico de Ciencias Básicas y Aplicadas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Urseler, Noelia Luján. Universidad Nacional de Villa María. Instituto Académico Pedagógico de Ciencias Básicas y Aplicadas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Morgante, Verónica. Universidad Tecnológica Metropolitana; Chile. Universidad Bernardo O’Higgins; ChileFil: Damilano, Gabriela. Universidad Nacional de Río Cuarto. Facultad de Ciencias Humanas. Departamento de Educación Física; ArgentinaFil: Porporatto, Carina. Universidad Nacional de Villa María. Instituto Académico Pedagógico de Ciencias Básicas y Aplicadas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Agostini, Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: Morgante, Carolina. Universidad Nacional de Villa María. Instituto Académico Pedagógico de Ciencias Básicas y Aplicadas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentin