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Maria Lúcia Ribeiro

Bio: Maria Lúcia Ribeiro is an academic researcher from Sao Paulo State University. The author has contributed to research in topics: High-performance liquid chromatography & Solid phase extraction. The author has an hindex of 18, co-authored 78 publications receiving 1363 citations.


Papers
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Journal ArticleDOI
TL;DR: In this article, a compact revision on the herbicide glyphosate physic-chemistry characteristic mains, including toxicity and valid Brazilian legislation for its use, is presented, along with a detailed discussion of its application in agriculture.
Abstract: This paper supplies a compact revision on the herbicide glyphosate physic-chemistry characteristic mains, including toxicity and valid Brazilian legislation for its use.

148 citations

Journal ArticleDOI
31 Dec 2003
TL;DR: In this paper, the authors present the definitions of the parameters (selectivity, limits of detection and quantification, accuracy, precision,linearity, analytical graphic, sensitivity and ruggedness) considered on analytical methods validation procedures.
Abstract: Neste trabalho sao apresentadas as definicoes dos parâmetros (seletividade, limites de deteccao e quantificacao, exatidao, precisao, linearidade, grafico analitico, sensibilidade e robustez) considerados nos processos de validacao de metodos analiticos. A estrategia a ser adotada para a determinacao desses parâmetros depende do proposito e da natureza do metodo. Exemplos sao apresentados para a avaliacao dos parâmetros no procedimento de validacao. ANALYTICAL METHODS VALIDATION: STRATEGY AND DISCUSSION Abstract This paper presents the definitions of the parameters (selectivity, limits of detection and quantification, accuracy, precision, linearity, analytical graphic, sensitivity and ruggedness) considered on analytical methods validation procedures. The strategy to be adopted for determinations of these parameters depends on the purpose and the nature of the method. Some examples are presented for parameters evaluation in a validation procedure.

144 citations

Journal ArticleDOI
TL;DR: Two simple methods were developed to determine 11 pesticides in coconut water, a natural isotonic drink rich in salts, sugars and vitamins consumed by the people and athletes, and no detectable amounts of the pesticides were found in any samples under the conditions described.

142 citations

Journal ArticleDOI
TL;DR: Biosensors for determination of carbamates in vegetables based on five different cholinesterase as biorecognition elements and a screen-printed electrode system as an amperometric transducer were developed Measurements were simply performed by dropping solutions (either sample or substrate) directly on the biosensor as discussed by the authors.
Abstract: Biosensors for determination of carbamates in vegetables based on five different cholinesterase as biorecognition elements and a screen-printed electrode system as an amperometric transducer were developed Measurements were simply performed by dropping solutions (either sample or substrate) directly on the biosensor The response of biosensors to selected carbamates (aldicarb, carbaryl, carbofuran, methomyl and propoxur) was characterized The performance was evaluated on extracts of potatoes and carrots, the results from the AChE biosensor and a standard HPLC procedure were compared Finally, the biosensor was used for the direct analysis of vegetable juices without any pretreatment steps In this case, 10 μg/L levels of added carbofuran and propoxur were reliably identified The whole procedure takes less than 20 min including 10 min incubation with samples The concentrations of carbamates determined with biosensor agreed well for carbofuran Lower response was observed for propoxur

91 citations

Journal ArticleDOI
TL;DR: It is deducted that the contamination of water resources is predominantly caused by non-point pollution of pesticides used in intensive cash-crop cultures of the Cerrado area, and a continuous monitoring of pesticide concentrations in water resources of this tropical region is necessary to detect the longer term contamination trends and developing health risks.
Abstract: Residues of the herbicides simazine, metribuzin, metolachlor, trifluralin, atrazine, and two metabolites of atrazine, deisopropylatrazine (DIA) and deethylatrazine (DEA), are surveyed in the surface and groundwater of the Primavera do Leste region, Mato Grosso, Brazil during September and December 1998 and April 1999. Different water source sampling stations of groundwater (irrigation water well, drinking water well, and water hole) and surface water (dam and river) are set up based on agricultural land use. A solid-phase extraction procedure followed by gas chromatography‐nitrogen-phosphorus detection is used for the determination of these compounds. All compounds are detected at least once in water samples. A temporal trend of pesticide contamination is observed, with the highest contamination frequency occurring in December during the main application season. Metribuzin shows the highest individual detection frequencies throughout the monitoring period, followed by metolachlor, simazine, and DEA. The maximum mean concentrations of pesticides in this study are in the range from 0.14 to 1.7 µg/L. We deduct that the contamination of water resources is predominantly caused by non-point pollution of pesticides used in intensive cash-crop cultures of the Cerrado area. Therefore, a continuous monitoring of pesticide concentrations in water resources of this tropical region is necessary to detect the longer term contamination trends and developing health risks.

66 citations


Cited by
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Journal ArticleDOI
TL;DR: The Pesticide Properties DataBase (PPDB) as discussed by the authors is a free-to-access database for all types of pesticide risk assessments. But, the PPDB is limited to 3,200 active substances and over 700 metabolites.
Abstract: Despite a changing world in terms of data sharing, availability, and transparency, there are still major resource issues associated with collating datasets that will satisfy the requirements of comprehensive pesticide risk assessments, especially those undertaken at a regional or national scale. In 1996, a long-term project was initiated to begin collating and formatting pesticide data to eventually create a free-to-all repository of data that would provide a comprehensive transparent, harmonized, and managed extensive dataset for all types of pesticide risk assessments. Over the last 20 years, this database has been keeping pace with improving risk assessments, their associated data requirements, and the needs and expectations of database end users. In 2007, the Pesticide Properties DataBase (PPDB) was launched as a free-to-access website. Currently, the PPDB holds data for almost 2300 pesticide active substances and over 700 metabolites. For each substance around 300 parameters are stored, cover...

1,015 citations

Journal ArticleDOI
TL;DR: There is strong evidence that soils, waterways, and plants in agricultural environments and neighboring areas are contaminated with variable levels of neonicotinoids or fipronil mixtures and their metabolites, and this provides multiple routes for chronic exposure of nontarget animals.
Abstract: Systemic insecticides are applied to plants using a wide variety of methods, ranging from foliar sprays to seed treatments and soil drenches. Neonicotinoids and fipronil are among the most widely used pesticides in the world. Their popularity is largely due to their high toxicity to invertebrates, the ease and flexibility with which they can be applied, their long persistence, and their systemic nature, which ensures that they spread to all parts of the target crop. However, these properties also increase the probability of environmental contamination and exposure of nontarget organisms. Environmental contamination occurs via a number of routes including dust generated during drilling of dressed seeds, contamination and accumulation in arable soils and soil water, runoff into waterways, and uptake of pesticides by nontarget plants via their roots or dust deposition on leaves. Persistence in soils, waterways, and nontarget plants is variable but can be prolonged; for example, the half-lives of neonicotinoids in soils can exceed 1,000 days, so they can accumulate when used repeatedly. Similarly, they can persist in woody plants for periods exceeding 1 year. Breakdown results in toxic metabolites, though concentrations of these in the environment are rarely measured. Overall, there is strong evidence that soils, waterways, and plants in agricultural environments and neighboring areas are contaminated with variable levels of neonicotinoids or fipronil mixtures and their metabolites (soil, parts per billion (ppb)-parts per million (ppm) range; water, parts per trillion (ppt)-ppb range; and plants, ppb-ppm range). This provides multiple routes for chronic (and acute in some cases) exposure of nontarget animals. For example, pollinators are exposed through direct contact with dust during drilling; consumption of pollen, nectar, or guttation drops from seed-treated crops, water, and consumption of contaminated pollen and nectar from wild flowers and trees growing near-treated crops. Studies of food stores in honeybee colonies from across the globe demonstrate that colonies are routinely and chronically exposed to neonicotinoids, fipronil, and their metabolites (generally in the 1–100 ppb range), mixed with other pesticides some of which are known to act synergistically with neonicotinoids. Other nontarget organisms, particularly those inhabiting soils, aquatic habitats, or herbivorous insects feeding on noncrop plants in farmland, will also inevitably receive exposure, although data are generally lacking for these groups. We summarize the current state of knowledge regarding the environmental fate of these compounds by outlining what is known about the chemical properties of these compounds, and placing these properties in the context of modern agricultural practices.

902 citations

01 Jan 2011
TL;DR: The presente estudo 3 as mentioned in this paper analyzes the condições de vida, trabalho, moradia, and escolarização of trabalhadores temporários nordestinos diante do crescimento das migraçóes na atualidade.
Abstract: O presente estudo 3 tem como tema a produção e reprodução da vida de trabalhadores migrantes temporários nordestinos da construção civil que trabalham no Campus central da Universidade Federal de Santa Catarina — UFSC, em Florianópolis/SC. Seu objetivo principal é analisar as condições de vida, trabalho, moradia e escolarização dos trabalhadores diante do crescimento das migrações na atualidade. Na pesquisa empírica foi realizado um trabalho de campo nos canteiros de obras no campus, com o propósito de identificar as empresas que prestam serviço na universidade e também quais as empresas que empregavam maior número de trabalhadores migrantes temporários nordestinos. Na coleta de dados foram realizadas entrevistas semiestruturadas com os trabalhadores migrantes e com as empresas nos canteiros de obras da universidade. A pesquisa de campo envolveu ainda conversas informais com os trabalhadores migrantes, com as empresas e registros fotográficos.

821 citations

Journal ArticleDOI
22 Feb 2013-Science
TL;DR: Global observations of water table depth compiled from government archives and literature are presented to fill in data gaps and infer patterns and processes using a groundwater model forced by modern climate, terrain, and sea level.
Abstract: Shallow groundwater affects terrestrial ecosystems by sustaining river base-flow and root-zone soil water in the absence of rain, but little is known about the global patterns of water table depth and where it provides vital support for land ecosystems We present global observations of water table depth compiled from government archives and literature, and fill in data gaps and infer patterns and processes using a groundwater model forced by modern climate, terrain, and sea level Patterns in water table depth explain patterns in wetlands at the global scale and vegetation gradients at regional and local scales Overall, shallow groundwater influences 22 to 32% of global land area, including ~15% as groundwater-fed surface water features and 7 to 17% with the water table or its capillary fringe within plant rooting depths

691 citations

Journal ArticleDOI
TL;DR: A review about the potential application of biosensor technology in drink and food industries, its current situation and potential is presented.

521 citations