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1.
Environ Sci Pollut Res Int ; 31(32): 45425-45440, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38965109

RESUMEN

Ivermectin (IVM) is a widely used antiparasitic. Concerns have been raised about its environmental effects in the wetlands of Río de la Plata basin where cattle have been treated with IVM for years. This study investigated the sublethal effects of environmentally relevant IVM concentrations in sediments on the Neotropical fish Prochilodus lineatus. Juvenile P. lineatus were exposed to IVM-spiked sediments (2 and 20 µg/Kg) for 14 days, alongside a control sediment treatment without IVM. Biochemical and oxidative stress responses were assessed in brain, gills, and liver tissues, including lipid damage, glutathione levels, enzyme activities, and antioxidant competence. Muscle and brain acetylcholinesterase activity (AChE) and stable isotopes of 13C and 15N in muscle were also measured. The lowest IVM treatment resulted in an increase in brain lipid peroxidation, as measured by thiobarbituric acid reactive substances (TBARs), decreased levels of reduced glutathione (GSH) in gills and liver, increased catalase activity (CAT) in the liver, and decreased antioxidant capacity against peroxyl radicals (ACAP) in gills and liver. The highest IVM treatment significantly reduced GSH in the liver. Muscle (AChE) was decreased in both treatments. Multivariate analysis showed significant overall effects in the liver tissue, followed by gills and brain. These findings demonstrate the sublethal effects of IVM in P. lineatus, emphasizing the importance of considering sediment contamination and trophic habits in realistic exposure scenarios.


Asunto(s)
Antiparasitarios , Ivermectina , Contaminantes Químicos del Agua , Animales , Ivermectina/toxicidad , Antiparasitarios/toxicidad , Contaminantes Químicos del Agua/toxicidad , Ganado , América del Sur , Estrés Oxidativo/efectos de los fármacos , Sedimentos Geológicos/química , Branquias/efectos de los fármacos , Branquias/metabolismo
2.
Sci Total Environ ; 920: 170993, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38369140

RESUMEN

This study explores the relationship between poultry farming's antibiotic administration practices and residual antibiotic levels in the litter before its application onto agricultural soils. Twenty-three antibiotics were performed across 19 Argentinean farms representing diverse antibiotic management practices. Analysis revealed up to 20 antibiotics from eight chemical classes in poultry litter samples, with tylosin, enrofloxacin, and salinomycin being the most relevant drugs. Farms with restricted antibiotic use in feed exhibited lower residual concentrations. A self-heating treatment was tested to reduce litter antibiotic levels. Although a 60 % reduction of antibiotics was found after treatment, prevalent compounds persisted at residual levels. Regulatory measures and comprehensive litter treatments pre-application are crucial to mitigate environmental risks. This is the first study that provides insight on the occurrence of >20 drugs in real poultry production scenarios from Latin America and demonstrates how relatively simple treatments can be readily applied to decrease the associated environmental risks.


Asunto(s)
Antibacterianos , Aves de Corral , Animales , Antibacterianos/análisis , Argentina , Agricultura , Enrofloxacina , Suelo/química , Estiércol/análisis
3.
Waste Manag ; 175: 204-214, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38218091

RESUMEN

This work studied the optimization of enzymatic saccharification of Agave tequilana bagasse (ATB) pretreated with the low-cost protic ionic liquid (PIL) ethanolamine acetate ([EOA][OAc]) using the highly available and cost-effective mixture of the enzymatic cocktails Celluclast 1.5L-Viscozyme L. Response surface methodology (RSM) was employed to maximize the sugars concentration and yield. The RSM optimization conditions of the enzymatic saccharification of pretreated ATB that achieved the maximum reducing sugars (RS) concentration were: 11.50 % w/v solids loading, 4.26 pH with 0.76 and 1.86 mg protein/mL buffer of Viscozyme L and Celluclast 1.5L, respectively. Similarly, the conditions that maximize the sugar yield (SY) were solids loading of 5.62 % w/v, and 4.51 pH as well as 1.07 and 2.03 mg protein/mL buffer of Viscozyme L and Celluclast 1.5L, respectively. Saccharification performance of the first-generation and low-cost enzyme mixture Celluclast 1.5L-Viscozyme L was compared with that reached by a second-generation and higher-cost CTec2, where Celluclast 1.5L-Viscozyme L achieved 60.86 ± 2.66 % y 79.25 ± 3.34 % of the sugars released by CTec2 at the same hydrolysis time (12 h) for the sugar concentration and yield models, respectively. These results are encouraging since they positively contribute to cost reduction and availability issues, which are key parameters to consider when thinking about scaling-up the process.


Asunto(s)
Agave , Celulosa , Líquidos Iónicos , Análisis Costo-Beneficio , Carbohidratos , Hidrólisis , Azúcares
4.
Environ Sci Pollut Res Int ; 30(54): 116078-116090, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37906333

RESUMEN

Carbamazepine is a widely used antiepileptic drug to control and treat a variety of disorders that is frequently detected in surface water, and in municipal and urban wastewater. This recalcitrant pollutant could be removed by alternative advanced oxidation technology such as heterogeneous photocatalysis. Ce-modified ZnO and Pd-modified TiO2 were synthesized by a microwave-assisted sol-gel method. According to the characterizations (Raman spectroscopy, UV-Vis diffuse reflectance spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy), a mixture of oxides was determined in both materials: CeO2/ZnO and PdO/TiO2. Photocatalytic degradation of carbamazepine in pure water under visible light (3 h) was assayed. The degradation percentage obtained with each catalyst was 80%, 53%, 20%, and 9% for ZnO, Ce-modified ZnO, TiO2, and Pd-modified TiO2, respectively. The leaching of Zn as a possible source of water contamination was tested, finding the lowest value for Ce-modified ZnO by adjusting the initial pH up to neutrality. Later, an environmentally relevant concentration of carbamazepine (228 µg L-1) was assayed, using local surface water (pH = 8.3). Despite the presence of other compounds in the real water matrix, after 5 h of photocatalysis, a 56% of degradation of the pharmaceutical and low leaching of Zn were achieved. The use of Ce-modified ZnO activated by visible light is a promising strategy for the abatement of pharmaceutical active compounds.


Asunto(s)
Agua , Óxido de Zinc , Óxido de Zinc/química , Luz , Titanio/química , Carbamazepina/química , Preparaciones Farmacéuticas , Catálisis
5.
J Environ Manage ; 347: 119149, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37783087

RESUMEN

The recent agricultural expansion in the Matopiba region, Brazil's new agricultural frontier, has raised questions about the risk of increasing soil organic carbon (SOC) loss as large areas of native vegetation (NV; i.e., Cerrado biome) have been replaced by large-scale mechanized agriculture. Although sustainable managements, such as integrated crop-livestock (ICL) systems, are considered strategic to counterbalance the SOC loss associated with land-use change (LUC) while keeping food production, little is known about their long-term effects on SOC stocks in the Matopiba region. To this end, we used the DayCent model to simulate the effects of converting the management commonly used in this region, i.e., soybean-cotton rotation under no-tillage (NT), into ICL systems with distinct levels of intensification (e.g., crop rotations: soybean-pasture and soybean-pasture-cotton; soil and crop management: grass irrigation, scarification/harrowing, and length of grass cultivation) on long term SOC dynamics. Additionally, data from two projected climate scenarios: SSP2-4.5 [greenhouse gases emissions (GHG) will not change markedly over time and global temperature will increase by 2.0 °C by 2060] and SSP5-8.5 (marked changes in GHG emissions are expected to occur resulting in an increase of 2.4 and 4.4 °C in global temperature in the middle and at the end of the century) were included in our simulations to evaluate climate change effects on SOC dynamics in this region. Based on a 50-yr-time frame simulation, we observed that SOC stocks under ICL systems were, on average, 23% and 47% higher than in the NV (36.9 Mg ha-1) and soybean-cotton rotation under NT (30.9 Mg ha-1), respectively. Growing grasses interlaid with crops was crucial to increase SOC stocks even when disruptive soil practices were followed. Although the irrigation of grass resulted in an early increase of SOC stocks and a higher pasture stoking rate, it did not increase SOC stocks in the long term compared to non-irrigated treatments. The SSP2-4.5 and SSP5-8.5 climate scenarios had little effects on SOC dynamics in the simulated ICL systems. However, additional SOC loss (∼0.065 Mg ha-1 yr-1) is predicted to occur if the current management is not improved. These findings can help guide management decisions for the Matopiba region, Brazil, to alleviate the anthropogenic pressure associated with agriculture development. More broadly, they confirm that crop-livestock integration in croplands is a successful strategy to regenerate SOC.


Asunto(s)
Cambio Climático , Suelo , Carbono/análisis , Brasil , Biodiversidad , Temperatura , Agricultura/métodos , Poaceae
6.
PLoS One ; 18(9): e0291304, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37721938

RESUMEN

OBJECTIVE(S): To examine associations between Index of Concentration at the Extremes (ICE) measures for economic and racial segregation and HIV outcomes in the United States (U.S.) and Puerto Rico. METHODS: County-level HIV testing data from CDC's National HIV Prevention Program Monitoring and Evaluation and census tract-level HIV diagnoses, linkage to HIV medical care, and viral suppression data from the National HIV Surveillance System were used. Three ICE measures of spatial polarization were obtained from the U.S. Census Bureau's American Community Survey: ICEincome (income segregation), ICErace (Black-White racial segregation), and ICEincome+race (Black-White racialized economic segregation). Rate ratios (RRs) for HIV diagnoses and prevalence ratios (PRs) for HIV testing, linkage to care within 1 month of diagnosis, and viral suppression within 6 months of diagnosis were estimated with 95% confidence intervals (CIs) to examine changes across ICE quintiles using the most privileged communities (Quintile 5, Q5) as the reference group. RESULTS: PRs and RRs showed a higher likelihood of testing and adverse HIV outcomes among persons residing in Q1 (least privileged) communities compared with Q5 (most privileged) across ICE measures. For HIV testing percentages and diagnosis rates, across quintiles, PRs and RRs were consistently greatest for ICErace. For linkage to care and viral suppression, PRs were consistently lower for ICEincome+race. CONCLUSIONS: We found that poor HIV outcomes and disparities were associated with income, racial, and economic segregation as measured by ICE. These ICE measures contribute to poor HIV outcomes and disparities by unfairly concentrating certain groups (i.e., Black persons) in highly segregated and deprived communities that experience a lack of access to quality, affordable health care. Expanded efforts are needed to address the social/economic barriers that impede access to HIV care among Black persons. Increased partnerships between government agencies and the private sector are needed to change policies that promote and sustain racial and income segregation.


Asunto(s)
Infecciones por VIH , Renta , Segregación Social , Adolescente , Adulto , Humanos , Población Negra , Tramo Censal , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Infecciones por VIH/etnología , Infecciones por VIH/terapia , Puerto Rico/epidemiología , Estados Unidos/epidemiología , Renta/estadística & datos numéricos , Población Blanca
7.
Sci Total Environ ; 851(Pt 1): 158142, 2022 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-35988611

RESUMEN

The current agricultural production model was established in the 1990s based on the use of genetically modified organisms and agrochemicals, mainly pesticides. Despite pesticide spread and prevalence, data on the associated concentrations in surface watercourses are comparatively scarce. The aim of this work was to evaluate to what extent the >20 years of agricultural activity with the use of pesticides has impacted on the Gualeguay-River basin, with respect to the different stream orders: the tributary streams and main channel. Thirteen sites within the lower Gualeguay basin were sampled once every season (autumn, winter, spring, and summer) in 2017-2018. The samples were analyzed by gas chromatography time-of-flight mass-spectrometry (GC-TOF-MS) and ultraperformance liquid chromatography tandem mass-spectrometry (UPLC-MS/MS). The most frequently detected pesticide was glyphosate along with its metabolite (aminomethyl)phosphonic acid (AMPA), at 82 % and 71 % of surface water samples and 97 % and 92 % of bottom sediments, respectively; followed by atrazine in 73 % of the water samples. The concentrations of these compounds, each in their respective matrices, did not present sufficient statistically significant differences for differentiating a tributary stream from the main channel. Regardless of glyphosate's affinity for the suspended particulate and bottom sediments, over the entire basin the soluble fraction contributed on average to >80 % of the total concentration in surface water. Despite not being so frequently detected, certain insecticides, mostly deltamethrin, were likewise detected at concentrations above their water-quality guidelines for the protection of aquatic life, even in samples from the main channel. Upon comparison of the pesticide profiles of extensive- and horticultural-production systems in the country, atrazine emerged as a prime candidate to be used as a tracer of extensive agriculture contamination in the environment. Further research is required to establish to what degree pesticides used in agriculture and mobilized by watercourses have an impact on their associated wetland ecosystems.


Asunto(s)
Atrazina , Insecticidas , Plaguicidas , Contaminantes Químicos del Agua , Agricultura , Argentina , Atrazina/análisis , Cromatografía Liquida , Ecosistema , Monitoreo del Ambiente , Insecticidas/análisis , Plaguicidas/análisis , Espectrometría de Masas en Tándem , Agua/análisis , Contaminantes Químicos del Agua/análisis , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/análisis
8.
Sci Total Environ ; 802: 149893, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34474294

RESUMEN

Peri-urban horticulture is crucial to local populations, but a global paucity of information exists regarding the contamination of the associated waterways because of this activity. The aim of this study was to assess pesticide pollution of surface water, suspended particulate matter and bottom sediments from the Carnaval Creek Basin (La Plata, Buenos Aires, Argentina) - a representative system of waterways surrounded by horticultural production - by over 40 selected herbicides, insecticides, and fungicides by gas-chromatography-time-of-flight mass spectrometry and ultraperformance liquid chromatography tandem mass spectrometry. Six sampling campaigns were conducted biannually from 2015 to 2017. Glyphosate and (aminomethyl)phosphonic acid (AMPA), surprisingly, were the most frequently detected pesticides, in concentrations comparable to those reported in areas with genetically modified extensive crops (maximum in water, 20.04 and 4.86 µg·L-1; in sediment, 1146.5 and 4032.7 µg·kgdw-1, respectively). The insecticides chlorpyrifos, cypermethrin and λ-cyhalothrin were detected in more than 30% of the samples. The concentrations tended to greatly exceed those previously reported - by up to more than 800 times for chlorpyrifos in water (maximum 2.645 µg·L-1) and more than 400 times for lambda-cyhalothrin in sediments (maximum 2607.7 µg·kgdw-1). The total pesticide concentration in surface water was found to be influenced by precipitation regimes but was independent of the season of the year, with precipitations of more than 140 mm diluting the pesticide concentrations to levels below detection limits. An environmental risk assessment performed with the pesticide concentrations of pesticides in surface water revealed that the surrounding horticultural activity posed a high risk for aquatic biota, with 30% of the samples exceeding the threshold value by more than a thousand times. We conclude that pesticides from horticultural use are a major threat to small streams and their biodiversity. This work provides valuable information that is scarce regarding the impact on watercourses exclusively as a consequence of horticulture.


Asunto(s)
Plaguicidas , Contaminantes Químicos del Agua , Argentina , Monitoreo del Ambiente , Horticultura , Plaguicidas/análisis , Medición de Riesgo , Contaminantes Químicos del Agua/análisis
9.
Sci Total Environ ; 703: 134717, 2020 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-31744696

RESUMEN

Glyphosate-based herbicides are used in horticulture to prepare the soil for planting and to remove weeds surrounding greenhouses. Superficial runoff from production units can lead to glyphosate reaching nearby water bodies. Previous publications reported glyphosate's high affinity for suspended solids. The aim of the present work was to investigate the occurrence and concentrations of glyphosate and aminomethylphosphonic acid (AMPA) in soluble and suspended-particulate-matter fractions within the basin of the Carnaval-Stream, a water body traversing a horticultural greenbelt. Glyphosate and AMPA were detected in 67% and 83% of the samples, occurring in both fractions simultaneously at respective maximum concentrations of 17.0 and 4.5 µg.L1 in the soluble fraction and 35,620 and 19,586 µg.kg1 in the particulates. Although the calculated partition coefficients Kd confirmed that these compounds had tended to be associated with the particulate matter, the soluble glyphosate and AMPA contributed, on the average, to more than 90% of the total water volume. Although the analysis of suspended particulates is considered a more sensitive strategy for glyphosate and AMPA detection in surface water, these results demonstrate the need to analyze the soluble phase. The continual occurrence throughout a 3-year sampling was sufficient evidence demonstrating the use of glyphosate in horticulture.

10.
Bull Environ Contam Toxicol ; 104(1): 35-40, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31740980

RESUMEN

Dimethoate (D) are among the most commonly used organophosphates insecticides in the world. To evaluate the toxicity of two D formulations were selected as test organisms tadpoles of Rhinella arenarum. This toad species has an extensive neotropical distribution and is easy to handle and acclimate to laboratory conditions. The tadpoles were exposed in an acute assay for 48 h to D soluble concentrates (DSC) and emulsifiable concentrates (DEC). The 48 h-LC50 (95% confidence limits) value of DSC was 57.46 mg L-1 (40.52-81.43) and to DEC was 12.76 mg L-1 (10.39-15.68). These differences in toxicity were statistically significant (p < 0.05). In both formulations, acetylcholinesterase), carboxylesterase, and glutathione-S-transferases enzyme activities varied significantly respect to those of control group (p < 0.05). The DEC formulation was the most toxic. These results would allow the assessment and characterization of potential ecological risks following the application of those formulations.


Asunto(s)
Bufo arenarum , Dimetoato/toxicidad , Insecticidas/toxicidad , Larva/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Acetilcolinesterasa/metabolismo , Animales , Dimetoato/química , Insecticidas/química , Larva/enzimología , Dosificación Letal Mediana , Pruebas de Toxicidad , Contaminantes Químicos del Agua/química
11.
Environ Int ; 133(Pt A): 105144, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31669774

RESUMEN

We studied for the first time three ionophore anticoccidial drugs: monensin (MON), lasalocid (LAS), and salinomycin (SAL) as emerging pollutants originating from animal and plant husbandry in surface waters (n = 89) in one of the most extensive hydrological basins in South América (Del Plata basin). The soluble fraction of ionophores was pretreated by solid-phase extraction and analyzed by LC-MS/MS at a limit of detection of 1.7 ng·L-1. A statistical approach noted the need to report parameters calculated by methods based on the number of observations and the censorship percentage over substitution methods for more precise estimations of environmental data with a high percentage of left-censored data. Water collectors adjacent to intensive-husbandry facilities, placed in direct runoffs from animal excreta, or in wastewater emissions contained median concentrations of MON and SAL approximately 70 times higher than those found in regional tributaries and main courses of 5 sub-basins of the pampas and mesopotamic regions, thus exhibiting a relevance to other similar agricultural pollutants widely reported as pesticides. Chemical speciation of these compounds in surface water was characterized especially for MON and SAL, where the pH and chemical oxygen demand of the natural water body was associated with the concentration of the soluble fraction. The concentrations in abundant rivers such as the Gualeguay deliver a contribution to a natural wetland such as the Paraná-River delta, which registered only one sample with a [MON] ≤ the limit of quantification. Since wetlands possess a limited removal capability, these affluent contributions recorded strongly indicate that attention must be paid to the development of guidelines involving quality criteria for assessing the impact of ionophore antibiotics on such ecosystems.


Asunto(s)
Antibacterianos/química , Ionóforos/química , Ríos/química , Contaminantes Químicos del Agua/química , Humedales , Agricultura , Animales , Argentina , Cromatografía Liquida , Espectrometría de Masas en Tándem
12.
Animal ; 12(12): 2598-2608, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30451143

RESUMEN

Electroejaculation (EE) is stressful and probably painful; thus the administration of anaesthesia is recommended to decrease those negative effects. However, anaesthesia has a direct risk of provoking death, but sedation is less risky than anaesthesia. At the same time, α2-adrenergic agonists may improve semen quality. Therefore, the aim of the present study was to compare the physiological and behavioural responses indicative of stress and possibly pain, and the semen quality in electroejaculated untreated, anaesthetised or sedated goat bucks. Semen was collected from eight bucks using three different procedures in all them (EE in untreated bucks, EE under sedation or EE under general anaesthesia). The number of vocalizations during EE and the behavioural pattern before and after procedures were recorded. Pain visual analogue scale (VAS) score was also determined during EE. Rectal temperature, heart rate, serum cortisol concentration, biochemical and haematological parameters were measured before and after each procedure, and sperm characteristics were determined. Bucks vocalised more often when untreated than sedated or anaesthetised (P<0.02). The pain VAS score was greater when bucks were untreated than sedated or anaesthetised (P<0.002). The rectal temperature, heart rate, total protein, albumin and haemoglobin concentrations were greater when bucks were untreated than anaesthetised or sedated (P<0.02). Serum cortisol increased after EE (P=0.0006), without differences between procedures. The frequency and duration of lying down after EE were greater when bucks were anaesthetised than sedated or untreated (P<0.05), and were also greater when bucks were sedated than untreated (P<0.05). The number of times that the animal tried to stand up after EE was greater when bucks were anaesthetised than sedated or untreated (P<0.02). The sperm mass motility was greater when bucks were anaesthetised or sedated than when they were untreated (P=0.048). When animals were sedated, the ejaculate contained more spermatozoa with functional plasma membrane (P=0.03) and morphologically normal (P=0.05) than when they were untreated. In conclusion, general anaesthesia and sedation decreased the stress and probably the pain response provoked by EE and especially sedation improved the quality of the semen collected.


Asunto(s)
Bienestar del Animal , Cabras/fisiología , Semen/fisiología , Anestesia/veterinaria , Animales , Conducta Animal , Eyaculación , Hidrocortisona/sangre , Masculino , Análisis de Semen/veterinaria , Motilidad Espermática , Espermatozoides/fisiología , Estrés Fisiológico
13.
Sci Total Environ ; 645: 89-96, 2018 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-30015122

RESUMEN

The presence in the atmosphere of glyphosate (GLP) and atrazine (ATZ) was investigated-those pesticides dominating the market in Argentina-through rain, as the main climatic phenomenon associated with wet deposition, both through analyzing source-receptor relationships with soil along with the climatic influences that may condition that transport and through estimating the annual deposition on the surface of the Argentine pampas. Rainwater samples (n = 112) were collected throughout each rainfall in urban areas of the pampas having different degrees of land use and with extensive crop production plus subsurface-soil samples (n = 58) from the relevant periurban sites. The herbicides-analyzed by liquid-chromatography-mass-spectrometry-were detected in >80% of the rain samples at median-to-maximum concentrations of 1.24-67.3 µg·L-1 (GLP) and 0.22-26.9 µg·L-1(ATZ), while aminomethylphosphonic acid (AMPA) was detected at 34% (0.75-7.91 µg·L-1). In soils, GLP was more frequently registered (41%; 102-323 µg·kg-1) followed by ATZ (32%; 7-66 µg·kg-1) and then AMPA (22%; 223-732 µg·kg-1). The maximum GLP concentrations quantified in rainwater exceeded the previously reported levels for the USA and Canada. No associations were observed between soil and rainwater concentrations in the same monitoring areas-despite the soil's action as a source, as evidenced through the AMPA present in rainwater. Median GLP concentrations were significantly associated with isohyets, in an increasing gradient from the east to the west-as such in an inverse pattern to that of the annual rainfall volumes; whereas ATZ-rainwater levels exhibited no characteristic spatial configuration. The estimated annual deposition of GLP by rainfall indicated that more than onc source of a herbicide can lead to its presence in the atmosphere and points out the relevance of rainfall's contribution to the surface levels of a pollutant.

14.
Chemosphere ; 202: 289-297, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29573614

RESUMEN

In the last years, the agricultural expansion has led to an increased use of pesticides, with glyphosate as the most widely used worldwide. This is also the situation in Argentina, where glyphosate formulations are the most commercialized herbicides. It is known that glyphosate formulations are much more toxic than the active ingredient, and this difference in toxicity can be attributed to the adjuvants present in the formula. In this context, the aim of the present study was to evaluate and compare sub-lethal histological effects of the glyphosate formulation Roundup Ultramax and glyphosate active ingredient on Leptodactylus latrans tadpoles at Gosner-stage 36. Semi-static bioassays were performed using 96 h of exposure with Roundup Ultramax formulation (RU; 0.37-5.25 mg a.e./L), glyphosate (GLY; 3-300 mg/L), and a control group. RU exposure showed an increment in the melanomacrophagic cells (MMc) and melanomacrophagic centers (MMCs) from 0.37 mg a.e./L. GLY exposure showed a significant increment in the number of MMc from 15 mg/L, and of MMCs from 3 mg/L. Also, histopathological lesions were observed in the liver of tadpoles exposed to both, GLY and RU. These lesions included: lipidosis and hepatic congestion, but only RU showed significant differences respect to control, with a LOEC value of 2.22 mg a.e./L for both effects. In sum, this study represents the first evidence of adverse effects of glyphosate and RU formulation on the liver of anuran larvae at concentrations frequently found in the environment.


Asunto(s)
Anuros/crecimiento & desarrollo , Glicina/análogos & derivados , Herbicidas/toxicidad , Larva/crecimiento & desarrollo , Hígado/crecimiento & desarrollo , Animales , Argentina , Glicina/toxicidad , Larva/efectos de los fármacos , Hígado/efectos de los fármacos , Glifosato
15.
Animal ; 12(1): 98-105, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28693662

RESUMEN

The aim of this study was to determine if the absence of the mother during rearing has long-term effects on sexual behaviour and physiological reproductive parameters of adult rams. Two groups of rams were: (1) artificially reared, separated from their dams 24 to 36 h after birth (Week 0) and fed using sheep milk until 10 weeks of age (group AR, n=14); and (2) reared by their dams until 10 weeks of age (group DR, n=13). Sexual behaviour (tests of 20 min) and physiological reproductive parameters were analysed separately for the non-breeding (Weeks 42 to 64) and the breeding (Weeks 66 to 90) seasons. Body weight, scrotal circumference, gonado-somatic index, testosterone concentrations or sperm parameters were similar in both rearing conditions (AR v. DR) in both seasons. During the non-breeding season AR rams displayed fewer ano-genital sniffings (AR: 4.2±0.4 v. DR: 5.3±0.4, P=0.04) and matings (AR: 1.2±0.2 v. DR: 1.8±0.2, P=0.002) than DR rams. During the breeding season AR rams displayed fewer ano-genital sniffings (AR: 4.3±0.5 v. DR: 5.7±0.5, P=0.005), flehmen (AR: 0.7±0.2 v. DR: 1.1±0.2, P=0.03), mount attempts (AR: 1.4±0.2 v. DR: 2.1±0.2, P=0.04), and tended to mount less frequently (AR: 6.6±0.9 v. DR: 8.8±0.9, P=0.08) than DR rams. In conclusion, the absence of the mother during the rearing period negatively affected display of sexual behaviour towards oestrous ewes during a rams adult life in both breeding and non-breeding seasons. However, it did not affect testis size, testosterone secretion or sperm variables.


Asunto(s)
Privación Materna , Reproducción/fisiología , Conducta Sexual Animal/fisiología , Desarrollo Sexual/fisiología , Ovinos/fisiología , Testosterona/sangre , Animales , Peso Corporal , Cruzamiento , Estro , Femenino , Masculino , Estaciones del Año , Ovinos/crecimiento & desarrollo , Espermatozoides/fisiología
16.
Rev Med Inst Mex Seguro Soc ; 55(6): 684-685, 2017.
Artículo en Español | MEDLINE | ID: mdl-29190858

RESUMEN

On August, the second edition of the Healthcare Book Fair took place, sponsored by the Facultad de Medicina of UNAM. Again, the Revista Médica del Instituto Mexicano del Seguro Social participated with a stand where we promoted it, talked about the different indexes where our journal is included, explained its objective and scope, and finally talked about its nature as an open access journal, which is aimed to the clinical staff of the different health institutions of our country.


El pasado mes de agosto tuvo lugar la segunda edición de la Feria del Libro de Ciencias de la Salud, auspiciada por la Facultad de Medicina de la UNAM. En ella de nueva cuenta tuvo participación la Revista Médica del Instituto Mexicano del Seguro Social con un stand donde se difundió la revista, su indexación en los diferentes índices en los que tenemos participación, se explicitó su objetivo y alcance y se manifestó como una revista de acceso abierto, gratuita, dirigida al personal clínico de las diferentes instituciones de salud del país.


Asunto(s)
Aniversarios y Eventos Especiales , Servicios de Salud , Publicaciones Periódicas como Asunto , Academias e Institutos , Libros , Humanos , México , Publicación de Acceso Abierto , Seguridad Social
17.
Nat Commun ; 8(1): 1013, 2017 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-29044104

RESUMEN

Mining poses significant and potentially underestimated risks to tropical forests worldwide. In Brazil's Amazon, mining drives deforestation far beyond operational lease boundaries, yet the full extent of these impacts is unknown and thus neglected in environmental licensing. Here we quantify mining-induced deforestation and investigate the aspects of mining operations, which most likely contribute. We find mining significantly increased Amazon forest loss up to 70 km beyond mining lease boundaries, causing 11,670 km2 of deforestation between 2005 and 2015. This extent represents 9% of all Amazon forest loss during this time and 12 times more deforestation than occurred within mining leases alone. Pathways leading to such impacts include mining infrastructure establishment, urban expansion to support a growing workforce, and development of mineral commodity supply chains. Mining-induced deforestation is not unique to Brazil; to mitigate adverse impacts of mining and conserve tropical forests globally, environmental assessments and licensing must considered both on- and off-lease sources of deforestation.

18.
Environ Pollut ; 229: 771-779, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28693752

RESUMEN

In the Pampas, public concern has strongly risen because of the intensive use of glyphosate for weed control and fallow associated with biotech crops. The present study was aimed to evaluate the occurrence and concentration of the herbicide and its main metabolite (AMPA) in soil and other environmental compartments of the mentioned agroecosystem, including groundwater, in relation to real-world agricultural management practices in the region. Occurrence was almost ubiquitous in solid matrices (83-100%) with maximum concentrations among the higher reported in the world (soil: 8105 and 38939; sediment: 3294 and 7219; suspended particulate matter (SPM): 584 and 475 µg/kg of glyphosate and AMPA). Lower detection frequency was observed in surface water (27-55%) with maximum concentrations in whole water of 1.80 and 1.90 µg/L of glyphosate and AMPA, indicating that SPM analysis would be more sensitive for detection in the aquatic ecosystem. No detectable concentrations of glyphosate or AMPA were observed in groundwater. Glyphosate soil concentrations were better correlated with the total cumulative dose and total number of applications than the last spraying event dose, and an increment of 1 mg glyphosate/kg soil every 5 spraying events was estimated. Findings allow to infer that, under current practices, application rates are higher than dissipation rates. Hence, glyphosate and AMPA should be considered "pseudo-persistent" pollutants and a revisions of management procedures, monitoring programs, and ecological risk for soil and sediments should be also recommended.


Asunto(s)
Agricultura , Monitoreo del Ambiente/métodos , Glicina/análogos & derivados , Herbicidas/análisis , Contaminantes del Suelo/análisis , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/análisis , Argentina , Productos Agrícolas , Glicina/análisis , Agua Subterránea , Suelo , Glifosato
19.
Sci Total Environ ; 598: 572-580, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-28454030

RESUMEN

Vegetable production systems are characterized by intense pesticide use, yet the effects on the surrounding environment are largely unknown and need to be studied. Given this knowledge gap, the objective of this work is to determine the impact of horticulture on a representative watercourse by conducting an integrated study of the occurrence and concentration of pesticides in bottom sediments and their relation to lethal and sublethal effects on benthic fauna. Two sampling campaigns were conducted during seasons of low and high pesticide application in five sites along the Carnaval creek, located in the peri-urban area of La Plata City (Buenos Aires, Argentina). The samples were tested for 36 pesticide compounds by GC-MS and LC-MS, and whole-sediment laboratory toxicity tests were performed using the native amphipod Hyalella curvispina. The results showed a general but variable distribution in the concentrations detected along the stream. For each sampling campaign (first/second), the total pesticide loads, measured as the sum of herbicides, insecticides and fungicides, were 1080/2329, 3715/88, and 367/5ngg-1 dw, respectively. Lethal and sublethal effects were observed in both sampling campaigns. In order to correlate both sets of results, data were assessed by multivariate analysis, including principal component analysis. The observed toxicity was considered to be mainly due to insecticides; thus, horticultural practices have an impact on nearby watercourses and can potentially endanger the benthic fauna. This is the first study in Argentina to assess the impact of pesticides on aquatic environments close to horticultural production areas.


Asunto(s)
Agricultura , Monitoreo del Ambiente , Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Anfípodos , Animales , Argentina , Sedimentos Geológicos/química , Ríos/química , Pruebas de Toxicidad
20.
Reprod Domest Anim ; 52(3): 403-408, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28120512

RESUMEN

Electroejaculation procedures (EEPs) provoke stress; nevertheless, ejaculation produces physiological changes similar as those usually used to measure stress responses. The application of EEP to animals that cannot ejaculate-as ewes-may be useful to discriminate the responses induced by ejaculation from those provoked by EEP. The aim was to determine the stress response to EEP in rams and ewes. The EEPs were applied to 10 rams and 10 ewes during the non-breeding season, and the number of vocalizations, the heart rate, rectal temperature, serum cortisol concentration, biochemical and haematological parameters were measured. Overall, EEP provoked increases in cortisol concentration, glycaemia, rectal temperature and concentration of creatine kinase (all them: p < .0001) as well as relative concentration of granulocytes (p = .003) and absolute granulocyte concentration (p = .0002) in both, rams and ewes. Heart rate, relative concentration of lymphocytes (p = .001), haematocrit (p = .02) and haemoglobin (p = .045) decreased in animals from both genders after EEP. Besides, cortisol (p < .0001), rectal temperature (p = .002) and glycaemia (p = .001) were greater in ewes than rams, and creatine kinase also tended to be greater in ewes than rams (p = .054). On the other hand, the number of animals that vocalized (p = .006), white blood cells (p = .02) and absolute lymphocytes (p = .02) were greater in rams than ewes. The general trends show a similar pattern of stress responses in animals from both genders. Therefore, we concluded that ejaculation does not contribute to the stress response provoked by the EEP. This procedure also provokes muscular damage and probably pain.


Asunto(s)
Eyaculación/fisiología , Estimulación Eléctrica/efectos adversos , Oveja Doméstica , Estrés Fisiológico , Animales , Temperatura Corporal , Femenino , Frecuencia Cardíaca , Pruebas Hematológicas/veterinaria , Hidrocortisona/sangre , Masculino , Vocalización Animal/fisiología
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