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1.
Environ Toxicol Chem ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629594

RESUMO

We evaluated the main leaching indices that have been used for decades for the protection of groundwater against contamination by pesticides. We describe the index classifications in detail and discuss their advantages and limitations relative to their prediction value. Most of the indices have similarities in the types of parameters they use. Some of the similarities are basic physicochemical properties of the pesticides such as their water solubility and their organic carbon partition coefficient, as well as characteristics such as environmental persistence in the soil and some soil characteristics. It is very difficult to maintain a simple index with high predictive power. However, comparisons are allowed by many indices among different active ingredients before pesticides are classified according to the risk of being groundwater contaminants. In contrast, limitations are the scarce inclusion of pesticide byproducts in the ground, lack of prediction capacity for polar pesticides, and lack of prediction of the vulnerability of groundwater to being contaminated by pesticides. Despite the limitations of such approaches, they are of great utility, particularly for protection of groundwater from pesticide contamination when little information is available, which is the case in most developing countries and in countries with economies in transition. Caution is recommended in the analysis of information generated by these approximations, which ideally should be validated experimentally in the different application scenarios and the needs for pesticide assessment based on local information. Environ Toxicol Chem 2024;00:1-14. © 2024 SETAC.

2.
Sci Total Environ ; 851(Pt 1): 158116, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-35988631

RESUMO

Pharmaceuticals and Personal Care Products (PPCPs) are emerging pollutants detected in many locations of the world including Antarctica. The main objective of this review is to discuss the influence of the human population on the concentration, distribution and biological effects of PPCPs across the Antarctic coastal marine ecosystem. We carried out a review of the scientific articles published for PPCPs in Antarctic, supported by the information of the Antarctic stations reported by Council of Managers of National Antarctic Programs (CONMAP), Scientific Committee on Antarctic Research (SCAR) and Secretariat of the Antarctic Treaty (ATS). In addition, spatial data regarding the Antarctic continent was obtained from Quantarctica. Antarctic concentrations of PPCPs were more reflective of the treatment system used by research stations as opposed to the infrastructure built or the annual occupancy by station. The main problem is that most of the research stations lack tertiary treatment, resulting in elevated concentrations of PPCPs in effluents. Furthermore, the geographic distribution of Antarctic field stations in coastal areas allows for the release of PPCPs, directly into the sea, a practice that remains in compliance with the current Protocol. After their release, PPCPs can become incorporated into sea ice, which can then act as a chemical reservoir. In addition, there is no clarity on the effects on the local biota. Finally, we recommend regulating the entry and use of PPCPs in Antarctica given the difficulties of operating, and in some cases the complete absence of appropriate treatment systems. Further studies are needed on the fate, transport and biological effects of PPCPs on the Antarctic biota. It is recommended that research efforts be carried out in areas inhabited by humans to generate mitigation measures relative to potential adverse impacts. Tourism should be also considered in further studies due the temporal release of PPCPs.


Assuntos
Cosméticos , Poluentes Ambientais , Poluentes Químicos da Água , Regiões Antárticas , Cosméticos/análise , Ecossistema , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Humanos , Preparações Farmacêuticas , Águas Residuárias/análise , Poluentes Químicos da Água/análise
3.
Environ Sci Pollut Res Int ; 25(5): 4596-4606, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29192400

RESUMO

Mercury concentrations in the environment tend to decrease in recent years due to environmental restrictions. Lakes store mercury in their sediments, making them potential secondary contamination sources. In South America, the occurrence of mercury in lake systems has been associated mainly with volcanic emissions and only few records anthropogenic contamination in the pre-Hispanic period. The objective of this research was to study historical anthropogenic mercury concentration in two lakes in Central Chile (La Señoraza and Pillo), in order to establish background mercury levels and their variations from preindustrial to modern periods. Different background levels and mercury concentrations were found in each lake, with significantly higher concentrations in Lake La Señoraza during the last 150 years. Mining-related activities during the nineteenth century could have a negligible influence on mercury concentrations. Later on, the use of coal railroads and subsequent employment of mercury in the cellulose industry were associated with three- and fourfold increases in mercury concentration over the nineteenth century background levels, which decrease once these activities ceased. However, in the case of Lake Pillo, an important increase in mercury concentration can be observed between 1990 and the early twenty-first century, which could be related to a higher watershed/lake area ratio, extensive agriculture, and volcanic emission, being the latter that could have contributed with mercury to both systems. Nevertheless, sedimentological characteristics in Lake Pillo can be favorable to retain mercury in this aquatic system up to the present day.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Lagos/química , Mercúrio/análise , Poluentes Químicos da Água/análise , Chile , Monitoramento Ambiental/história , História do Século XIX , História do Século XX , História do Século XXI , Indústrias/história , Mineração/história , Urbanização
4.
Nutr Hosp ; 34(1): 122-127, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28244782

RESUMO

INTRODUCTION: The determination of the morphological characteristics of the most popular sports has allowed the evaluation and comparison between athletes, which has helped to improve their performance. The Street Workout is an emerging sport based on calisthenics, which recently has become popular. Despite its popularization, neither the morphologic profile nor the morphologic characteristics of Street Workout athletes has been determined. OBJECTIVE: Determine the profile and morphological characteristics of Street-Workout athletes, through anthropometry. MATERIAL AND METHODS: Fourteen athletes (22.7 ± 3.26 years) were recruited from the National Calisthenics Tournament 2015 in Chile. The athletes were evaluated following the protocol of the International Society for the Advancement of Kinanthropometry to determine the somatotype, body composition, as well as indices of body composition such as body mass index, waist to hip ratio, waist to height ratio, fat/muscle mass and muscle/bone mass indexes. RESULTS: Street Workout practitioners presented a balanced-mesomorphic somatotype, a low fat mass and a high muscular development, with upper arms and trunk predominance. Regarding body composition indices, the values obtained allow us to classify them as a low-risk population of chronic non-communicable diseases. CONCLUSION: The present study sets a first antecedent of the morphological characteristics of Street Workout, determining that the Street Workout athletes presented balanced-mesomorphic somatotype and were classified as a healthy and athletic sample by their body composition indexes.


Assuntos
Composição Corporal , Condicionamento Físico Humano , Somatotipos , Adulto , Atletas , Feminino , Humanos , Masculino , Esportes , Adulto Jovem
5.
Int. j. morphol ; 33(3): 1165-1170, Sept. 2015. ilus
Artigo em Espanhol | LILACS | ID: lil-762603

RESUMO

El objetivo del presente estudio es determinar el somatotipo y la composición corporal de la selección masculina de fútbol universitario bicampeona del año 2013 y realizar la comparación de éstos entre posiciones de juego y con otras poblaciones de futbolistas. Se realizó una evaluación kineantropométrica a trece jugadores de la selección masculina de fútbol de la Pontificia Universidad Católica de Valparaíso (PUCV) 2013, utilizando el perfil completo del protocolo de la Sociedad Internacional para el Avance de la Kineantropometría (ISAK). Las mediciones se realizaron en pretemporada. Se determinó que el somatotipo de la selección masculina de fútbol de la PUCV 2013 corresponde a Endo-Mesomorfo (3,5­5,6­1,7). Los valores de composición corporal promedio de la selección de fútbol PUCV fueron 25,81% de masa grasa, 47,41% de masa muscular, 10,68% de masa ósea, 5,07% de masa piel y 11,03% de masa residual. No se encontraron diferencias significativas en los resultados expuestos en las diferentes posiciones en el campo de juego, con respecto a somatotipo, composición corporal y variables kineantropométricas analizadas (valor p >0,05). El perfil somatotípico de la selección masculina de fútbol de la PUCV 2013 es Endo-Mesomorfo, resultado similar al encontrado en otro estudio realizado en futbolistas universitarios. En cuanto a la composición corporal se observó que los porcentajes de tejido muscular y óseo se encuentran dentro de los rangos aceptables, mientras que el tejido graso se encuentra elevado respecto a otras poblaciones de futbolistas profesionales y universitarios.


The objective of this study was to determine the somatotype and body composition of the male university soccer team at Pontificia Universidad Católica de Valparaíso (PUCV) and then compare them, according to playing positions and other soccer populations. Thirteen players of the university soccer team at PUCV underwent a kineanthropometric evaluation, using the full profile of the International Society for the Advancement of Kinanthropometry (ISAK) protocol. The measures were performed in the 2013 pre-season. The somatotype of the male soccer team at PUCV corresponds to endomorphic-mesomorph (3.5­5.6­1.7). The average values of the body composition of the soccer team were 25.81% of fat mass, 47.41% of muscle mass, 10.68% of bone mass, 5.07% of skin mass and 11.03% of residual mass. No significant differences were observed among different playing positions with respect to the somatotype, for either body composition or any kineanthropometric variables analyze (p value >0.05). The somatotypical profile of the male university soccer team at PUCV is endo-mesomorphic, which is in accordance to a similar study conducted on university soccer players in Mexico. According to body composition, it was observed that the percentages of muscle and bone mass are in the acceptable ranges, while fat mass is elevated compared to other professional populations as well as other university soccer players.


Assuntos
Humanos , Masculino , Adulto Jovem , Composição Corporal , Futebol , Somatotipos , Chile
6.
Nutr Hosp ; 32(3): 1228-33, 2015 Sep 01.
Artigo em Espanhol | MEDLINE | ID: mdl-26319843

RESUMO

INTRODUCTION: the proportionality model application, based on ideal proportions, would have a great impact on high performance sports, due to best athletes to resemble anthropometrically. OBJECTIVE: the objective of this study was to compare the following anthropometric methods of proportionality: Phantom, Combined and Scalable, in male champion university Chilean soccer players in 2012 and 2013, using South American professional soccer players as criterion, in order to find the most appropriate proportionality method to sports populations. METHOD: the measerement of 22 kinanthropometric variables was performed, according to the ISAK protocol, to a sample constituted of 13 members of the men's soccer team of the Pontificia Universidad Católica de Valparaíso. The Z-values of the anthropometrics variables of each method were obtained using their respective equations. It was used as criterion population South American soccer players. RESULTS: a similar trend was observed between the three methods. Significant differences (p < 0.05) were found in some Z-values of Scalable and Combined methods compared to Phantom method. No significant differences were observed between the results obtained by the Combined and Scalable methods, except in wrist, thigh and hip perimeters. CONCLUSION: it is more appropriate to use the Scalable method over the Combined and Phantom methods for the comparison of Z values in kinanthropometric variables in athletes of the same discipline.


Introducción: la aplicación de modelos de proporcionalidad, basados en proporciones ideales, tendría un gran impacto en el deporte de alto rendimiento, debido a que los mejores deportistas tienden a asemejarse antropométricamente. Objetivo: el objetivo de este estudio es comparar los métodos de proporcionalidad antropométrica: Phantom, Combinado y Escalable, en los campeones chilenos de fútbol masculino universitario de los años 2012 y 2013, ocupando como población de criterio a futbolistas profesionales sudamericanos, con el fin de encontrar el método de proporcionalidad más adecuado para poblaciones de deportistas. Metodología: se realizó la evaluación de 22 variables kineantropométricas, según el protocolo ISAK, a una muestra constituida por 13 jugadores pertenecientes a la selección masculina de fútbol de la Pontificia Universidad Católica de Valparaíso. Se obtuvieron los valores Z de cada variable antropométrica de los diferentes métodos, usando sus fórmulas respectivas. Se usó como población de criterio a los futbolistas profesionales sudamericanos. Resultados: se observó una tendencia semejante entre los tres métodos. Se encontraron diferencias significativas (p < 0,05) en los valores Z de los métodos Escalable y Combinado, respecto al método Phantom. No se encontraron diferencias significativas entre los resultados obtenidos por los métodos Combinado y Escalable, excepto en los perímetros radiocarpiano, cadera y muslo. Conclusión: se propone la utilización del método Escalable sobre el método Combinado y Phantom para realizar la comparación de valores Z en variables kineantropométricas en deportistas de la misma disciplina.


Assuntos
Antropometria , Atletas , Antropometria/métodos , Pesos e Medidas Corporais , Chile , Humanos , Masculino , Modelos Teóricos , Futebol
7.
Waste Manag Res ; 31(10): 969-78, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23771880

RESUMO

The goal of this work was to evaluate a washing process that uses organic solutions for polychlorinated biphenyl (PCB)-contaminated soil, and includes an ultrasound pre-treatment step to reduce operational times and organic solvent losses. In a preliminary trial, the suitability of 10 washing solutions of different polarities were tested, from which three n-hexane-based solutions were selected for further evaluation. A second set of experiments was designed using a three-level Taguchi L27 orthogonal array to model the desorption processes of seven different PCB congeners in terms of the variability of their PCB concentration levels, polarity of the washing solution, sonication time, the ratio washing solution/soil, number of extraction steps and total washing time. Linear models were developed for the desorption processes of all congeners. These models provide a good fit with the results obtained. Moreover, statistically significant outcomes were achieved from the analysis of variance tests carried out. It was determined that sonication time and ratio of washing solution/soil were the most influential process parameters. For this reason they were studied in a third set of experiments, constructed as a full factorial design. The process was eventually optimized, achieving desorption rates of more than 90% for all congeners, thus obtaining concentrations lower than 5 ppb in all cases. The use of an ultrasound-assisted soil washing process for PCB-contaminated soils that uses organic solvents seems therefore to be a viable option, especially with the incorporation of an extra step in the sonication process relating to temperature control, which is intended to prevent the loss of the lighter congeners.


Assuntos
Poluição Ambiental/prevenção & controle , Recuperação e Remediação Ambiental/métodos , Hexanos/química , Bifenilos Policlorados/química , Poluentes do Solo/química , Solventes/química , Ultrassom/métodos , Cromatografia Gasosa , Modelos Teóricos
8.
Chemosphere ; 66(10): 1911-21, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17049964

RESUMO

Sediment cores from four Chilean lakes along the Andes Chain (Chungará, Laja, Castor and Venus) were analysed in order to investigate PCB concentrations and distributions in sediment samples. Sediment cores were analysed for PCBs using gas chromatography (GC-ECD/MS) and radioisotopically dated using 210Pb. Organic carbon content (OC) and 210Pb fluxes were also measured. Results showed that sediment PCB concentrations (ngg(-1) d.w.) at Lake Chungará (1.2 +/- 1) in northern Chile, Laja (5 +/- 4) in central, and in Lake Castor (3.5 +/- 4) in southern Chile (the eastern side of the Andes Mountain) were lower than sediments collected from Lake Venus (64 +/- 30) located in southern Chile (the western side) which contained 15-fold higher concentrations of PCBs. The percentage (%) of organic carbon was variable and showed a high range of values in the sediment fluctuating from 2% (Lake Laja) to 22% (Lake Chungará). Analysis of 210Pb fluxes, presented a decrease trend following Lake Laja>Castor>Chungará with a positive correlation with rainfall at each site. Sedimentation rates in Lake Castor (1846 gm(-2)yr(-1)) were higher than at Chungará (748 gm(-2)yr(-1)) and Lake Laja (508 gm(-2)yr(-1)). Focusing factor (FF) is used as a tool to elucidate PCB input in the aquatic ecosystem. FF were lower (<1) for the shallower lakes (Lakes Chungará and Castor). This study provides background levels of PCBs at remote lakes in Chile. Differences in geographical characteristics (orographic effect) might play an important role in the arrival of PCBs, particularly into the southern lakes. PCB fluxes indicated deposition of PCBs in recent sediments is higher than in previous years with peaks of PCB between 1991 and 1998. The continuing increase of PCB inputs in remote Chilean lakes, could be associated with long range atmospheric transport (LRAT).


Assuntos
Água Doce/análise , Sedimentos Geológicos/análise , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise , Carbono/análise , Chile , Cromatografia Gasosa-Espectrometria de Massas , Geografia , Radioisótopos de Chumbo/análise
9.
Ecotoxicol Environ Saf ; 63(1): 52-60, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16169082

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in the environment; they are of concern due to their toxic properties. Anthropogenic activities could contribute in a significant way to the total burden of PAHs in remote mountain areas. In this work, we document the analysis of PAHs deposition through sedimentary records obtained in three remote Andean lakes located in south central Chile. Sediment cores were taken in one of the deepest sections of each lake, ranging from 45 to 135 m depth. Sediments were carefully extruded in 1-cm layers for PAHs and dating analysis (210Pb and 137Cs). Sixteen Environmental Protection Agency prioritary PAHs were analyzed using high-performance liquid chromatography with fluorescence detection. Dating of sediments was possible for only two lakes (Laja and Galletue). The superficial composition of PAHs in each lake is rather similar with a characteristic dominance of perylene; levels ranged 355 to 3050 ng g(-1) d.w. Depositional fluxes averaged 118 microg m2 year(-1) in Laja Lake in contrast to that in Galletue Lake, where average fluxes reach 434 microg m2 year(-1). Dating back to 50 years, PAH profiles did not experience drastic changes despite the rapid development of industrialization over the past 30 years in the surrounding region, indicating that levels and composition remains fairly similar to those of the present. Finally, determined fluxes were in the lower range of depositional fluxes calculated for lakes located in the industrialized northern hemisphere.


Assuntos
Sedimentos Geológicos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Altitude , Radioisótopos de Césio , Chile , Monitoramento Ambiental , Água Doce , Radioisótopos de Chumbo
10.
Sci Total Environ ; 349(1-3): 150-60, 2005 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-16198677

RESUMO

This paper reports the occurrence of polyaromatic hydrocarbons (PAHs) deposition inferred from a sediment core of an Andean lake in south central Chile. Sediments were carefully collected from one of the deepest section of the lake and sliced every 1 cm. The samples were analyzed for PAHs, (137)Cs, (210)Pb, organic carbon and grain-size. The stratigraphic chronology and the sedimentation rates were estimated using the sedimentary signature left by the (137)Cs and (210)Pb fallout as temporal markers. PAHs were quantified by HPLC-fluorescence detection (HPLC-Fluorescence). 15 priority EPA PAHs were analyzed in this study. Based on these results, PAH deposition over the last 50 years was estimated (a period characterized by an important intervention in the area). PAH concentration ranged from 226 to 620 ng g(-1) d.w. The highest concentrations of PAHs were found in the core's bottom. The PAH profile is dominated by the presence of perylene indicating a natural source of PAH. In addition, two clear PAH deposition periods could be determined: the most recent with two-four rings PAHs, the older one with five-seven rings predomination. Determined fluxes where 71 to 972 microg m(-2) year(-1), dominated by perylene deposition. PAH levels and fluxes are lower compared to the levels found in sediments from remote lakes in Europe and North America. It is concluded that the main source of PAHs into the Laja Lake sediments are of natural origin.


Assuntos
Sedimentos Geológicos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Carbono/análise , Chile , Monitoramento Ambiental , Água Doce , Radioisótopos de Chumbo , Nitrogênio/análise , Tamanho da Partícula
11.
Chemosphere ; 55(7): 965-72, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15051366

RESUMO

This paper documents the occurrence of polychlorinated biphenyl (PCB) and hexachlorocyclohexane (HCH) deposition inferred from a sedimentary record exposed in a salt-marsh trench in South-Central Chile. Sediments were carefully collected every 1 cm from the trench wall. The samples were analyzed for PCBs, HCHs, 137Cs, organic carbon and grain size. The 137Cs fallout and the sedimentary signature left by the 1960 Chilean tsunami were used as temporal markers to estimate the stratigraphic chronology and the sedimentation rates. PCBs were quantified by gas chromatography with electron capture detection (GC-ECD), and positive samples were confirmed by gas chromatography and mass spectrometry detection (GC-MS). Based on these results, PCBs and HCHs deposition over the last 40 years was estimated. No PCBs were detected below the tsunami signature. Total concentrations ranged from undetectable (ND) to 32 ng/g d.w. for PCBs and from undetectable (ND) to 1.29 ng/g d.w. for HCHs. The highest PCB concentrations were found in the upper 7 cm of the core. Even though PCBs were banned in 1982 as electrical fluids in Chile, total estimated PCB fluxes have increased approximately 20 times during the last 40 years: from undetectable values to 102.6 ng/cm2/year, reflecting that PCBs are still in use and being released into the environment.


Assuntos
Sedimentos Geológicos/análise , Hexaclorocicloexano/análise , Bifenilos Policlorados/análise , Carbono/análise , Radioisótopos de Césio/análise , Chile , Cromatografia Gasosa-Espectrometria de Massas , Fatores de Tempo , Movimentos da Água
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