This study evaluated the environmental occurrence of fifty-one pesticides, pharmaceuticals and personal care products (PPCPs) in surface and drinking water samples collected in southern Brazil over a 4-year period. The method used involved a stage based on solid-phase extraction, followed by liquid chromatography tandem mass spectrometry. Thirty compounds were detected (22 different pesticides and 8 PPCPs) and at least four compounds were identified in more than 50% of the samples. Atrazine was the most frequently detected pesticide and it was found at concentrations between 5 and 49 ng L-1. From PPCPs, glibenclamide, methylparaben and nimesulide were the most commonly detected in both drinking water and surface water samples. Results showed the extent to which traces of pesticides and PPCPs were present in water samples from this region.

An investigation was conducted to standardize conditions for laccase and lipase activity required to maximize trichothecene degradation. The analytical methods were suitable and validated in model solutions for detection of five analytes (T-2 toxin, deoxynivalenol, nivalenol, 3-acetyldeoxynivalenol and 15-acetyldeoxynivalenol), the methods were then applied in the degradation tests of these trichothecenes. The method of salting-out assisted liquid-liquid extraction (SALLE), using three different NaCl concentration levels, obtained recoveries in the range of 47.4-103.4% at pH 5.0 and 36.6-106.8% at pH 7.0, with an intra-day relative standard deviation under 15% for the majority of the compounds. Quantification limits remained in the region of 0.07 µg mL-1 for 15-acetyldeoxynivalenol and 0.3 µg mL-1 for nivalenol. Finally, the suitable analytical methods were applied in a study of trichothecene degradation by enzymatic action, resulting in a reduction of 12.3% for T-2 toxin, 68.4% for deoxynivalenol, 50.2% for 3-acetyldeoxynivalenol and 45.4% for 15-acetyldeoxynivalenol.

Ionic liquid-dispersive liquid-liquid microextraction (IL-DLLME) was used for the determination of different chemical classes of analytes for the first time. Limits of quantification (LOQs) ranged from 0.5 to 2.5 µg L-1, and the linearity ranged from the LOQ of each compound to 50 µg L-1. Recoveries ranged from 70 to 120% for the compounds, with relative standard deviations less than 18%. The proposed method demonstrates for the first time that sample preparation by IL-DLLME and determination by liquid chromatography-tandem mass spectrometry (LC-MS/MS) can be used successfully for the simultaneous extraction of 19 kinds of pesticides and 16 PPCPs from water samples. In addition, to eliminate the environmental risk of waste solvent disposal, this technique uses a low-toxicity extraction solvent. Finally, the analytical method proposed was applied successfully in analysis in surface water samples.

This study aimed to develop and optimize an efficient photocatalytic process employing ruthenium [Ru(bipy)3]2+ doped TiO2-SiO2 for degrading synthetic wastewater containing six classes of pesticides (bentazone, carbofuran, clomazone, diuron, tebuconazole and pyraclostrobin). To optimize the degradation conditions for the six pesticides and assess the effect of two variables (reaction time and adsorption equilibrium time) on the heterogeneous photocatalytic process, a 22 experimental design with a central composite rotatable design (CCRD) was used. The CCRD was suitable for optimizing the heterogeneous photocatalysis, and the generated surface responses indicated that the best removal conditions were 15 min adsorption equilibrium time and 110 min reaction time. Under these conditions, a pesticide removal between 71.00 and 99.98% was obtained. Furthermore, the system yielded an excellent degree of synthetic wastewater mineralization, with 97.60% total organic carbon (TOC) removal after 110 min.

Mineral water is known for its high purity. Because mineral water is produced by the infiltration of water through the soil, there is the possibility of contamination with pesticides. The aim of this study was to develop a simple, rapid and efficient method for the extraction and preconcentration of different classes of pesticides in mineral water samples by dispersive liquid-liquid microextraction (DLLME) coupled with liquid chromatography tandem mass spectrometry. To optimize the DLLME conditions for the different classes of pesticides and access the effect of variables on the extraction, a central composite design (CCD) with a five-level fractional factorial design was used for the construction of a second order response surface model (RSM). The limits of quantification were between 0.005 and 0.5 μg L-1. Correlation coefficients (r) were higher than 0.999. Recoveries ranged from 102 to 120%, with relative standard deviations between 1 and 10%. Low matrix effect for all compounds was observed. The result showed that using a mixture of acetone and acetonitrile as disperser solvent and a mixture of chloroform and monochlorobenzene as extractor solvent, it is possible to employ the traditional DLLME with chlorinated solvents to extract the multiclass pesticides from the water samples.

Um método para determinação de diuron e irgarol utilizando extração em fase sólida (SPE) com C18 e cromatografia líquida acoplada a espectrometria de massas com ionização por eletronebulização foi otimizado, validado e aplicado em amostras de águas estuarinas e costeiras sob influência dos portos de Rio Grande. Os impactos da pré-filtração e salinidade no processo de SPE, utilizando C18 e adsorvente polimérico, foram avaliados e não foi observado efeito. Recuperações entre 95 e 118% (desvio padrão relativo < 20%) e limites de detecção e quantificação do método de 1,3 e 4 ng L-1, respectivamente, foram determinados para ambos os compostos. As curvas analíticas apresentaram coeficientes de correlação maiores que 0,99. O efeito matriz foi menor que 20% para irgarol e entre 45,7 e 63,5% para diuron. Diuron e irgarol foram encontrados em 8 e 9 dos 21 locais amostrados, respectivamente, com concentrações variando entre < 1,3 a 20,9 ng L-1. As baixas concentrações encontradas, juntamente com as restrições internacionais de uso e a sua ausência nas quatro tintas anti-incrustantes usadas na região, indicam que os níveis de irgarol e diuron são provavelmente pouco relevantes nesta região. Além disso, estão abaixo daquelas capazes de causar danos às espécies aquáticas.

A method for the determination of irgarol and diuron using C18 solid-phase extraction (SPE) and liquid chromatography with electrospray interface tandem mass spectrometry was optimized, validated and applied in estuarine and coastal waters under the influence of Rio Grande harbors (Patos Lagoon). The impact of pre-filtration and salinity in the extraction processes by SPE using C18 and polymeric adsorbents were evaluated and no effect was detected. Recoveries between 95 and 118% (relative standard deviation lower than 20%) and limit of detection and quantification for the method of 1.3 and 4 ng L-1, respectively, were reached for both compounds. The analytical curves presented correlation coefficients higher than 0.99. The matrix effect was lower than 20% for irgarol and between 45.7 and 65.3% for diuron. Diuron and irgarol were detected in 8 and 9 out of 21 sampled sites, respectively, with concentrations ranging from < 1.3 to 20.9 ng L-1. The low concentrations found, together with international restrictions of use and their absence in the four main antifouling paints used in the region, indicate that levels of diuron and irgarol are probably not relevant in this region. In addition, these levels were below of those capable of causing effects on tested species.

Esse estudo descreve pela primeira vez o uso do método ASTM D6584 para a determinação de glicerol e glicerídeos em amostras de ésteres etílicos de biodiesel obtidas a partir de óleo de girassol e da mistura de óleo de soja/sebo; e amostras de ésteres metílicos de biodiesel produzidas a partir da mistura de óleo de soja/tungue e de óleo de tungue. Os resultados mostraram que o método ASTM D6584 pode ser empregado para outras fontes de biodiesel, as quais representam uma alternativa para a produção de biodiesel, principalmente no Brasil.

This study describes for the first time the determination of glycerol and glycerides in samples of biodiesel ethyl esters from sunflower oil and soybean/tallow mixture and biodiesel methyl esters from soybean/tung mixture and tung oil by employing ASTM D6584 method. The results showed that ASTM D6584 can be used for other sources of biodiesel which represent an alternative to biodiesel production, mainly in Brazil.

Sarcocornia ambigua é uma planta herbácea perene, nativa da América do Sul e uma nova oleaginosa com potencial para forrageira, cultivada por irrigação direta com água salgada. Suas pequenas sementes se desenvolvem dentro dos segmentos do seu caule cilíndrico sem folhas e, durante a colheita, as sementes se misturam com o material celulósico remanescente de difícil separação. Este trabalho avalia diferentes métodos de extração e a composição dos ácidos graxos esterificados na farinha de caules férteis de S. ambigua, visando uma matéria-prima alternativa e um maior rendimento lipídico. Um maior rendimento lipídico foi obtido utilizando uma mistura (2:1)(v/v) de clorofórmio e metanol (5,2% da massa seca). Os ácidos graxos poli-insaturados mais abundantes na farinha foram o ácido linoleico (C18:2; 21,4%) e o ácido oleico (C18:1; 18,3%). Cinquenta e seis porcento dos lipídios da farinha de S. ambigua foram saturados e o ácido palmítico (C16:0) foi a principal fração (19,8%). Os ácidos graxos de cadeias longas (≥ C20) representaram 29,5% dos lipídios da farinha. Os ácidos graxos de cadeias longas mais abundantes foram o ácido behênico (C22:0; 7,1%), lignocérico (C24:0; 5,3%) e o ácido montânico (C28:0; 4,0%). A porcentagem de lipídios saturados na farinha de S. ambigua é significativamente maior do que os óleos comerciais com perfil nutricional MUFA e alguns dos lipídios encontrados possuem propriedades bioativas reconhecidas.

Sarcocornia ambigua is a perennial glasswort, native of South America and a potential new seed-oil crop and forage for direct irrigation with salt water. Small seeds develop inside fertile segments of its cylindrical leafless shoots and, at the harvest, seeds are typically mixed with remnant cellulose material difficult to separate. This work evaluated different extraction methods and the composition of total esterified fatty acids in a meal of ground fertile shoots of S. ambigua, seeking for an alternative primary matter and larger yield of total lipids. The highest lipid yield was obtained with a chloroform:methanol mixture (2:1)(v/v) (5.2% of dry weight). The most abundant polyunsaturated fatty acids in the meal were linoleic acid (C18:2; 21.4%) and oleic acid (C18:1; 18.3%). Fifty six percent of the lipids in S. ambigua meal were saturated and palmitic acid (C16:0) was the main fraction (19.8%). Long-chain fatty acids (≥ C20) represented 29.5% of the lipids. Most abundant long-chain fatty acids were behenic acid (C22:0; 7.1%), lignoceric acid (C24:0; 5.3%) and montanic acid (C28:0; 4.0%). The percentage of saturated lipids in S. ambigua meal was higher than that of vegetable oils with a MUFA nutritional profile and some of these lipids have known bioactive properties.

Atualmente as nações industrializadas se deparam com um novo problema, a contaminação das águas por contaminantes emergentes, entre eles fármacos e produtos de cuidado pessoal (PPCPs). Neste trabalho, um método analítico empregando extração em fase sólida (SPE) e cromatografia líquida com fonte de ionização eletrospray acoplada com espectrometria de massas em série foi desenvolvido e validado para a determinação de nimesulida, amitriptilina, enalapril, glibenclamida, haloperidol e metilparabeno em amostras de água. O estudo da SPE envolveu a utilização de um planejamento fatorial fracionado 2v5-1 para a seleção das variáveis que afetam o procedimento de extração. Os limites de detecção variaram de 0,01 a 0,2 µg L-1 e os de quantificação de 0,05 a 1,0 µg L-1. Obteve-se uma boa linearidade (coeficiente de determinação, r > 0,99) para todos os compostos. As recuperações variaram entre 65 e 120% com valores de desvio padrão relativo (RSD) menores que 20%. O método foi aplicado para a determinação de PPCPs em amostras de água superficial e potável durante 3 meses. Os níveis de PPCPs detectados foram da ordem de µg L-1.

Currently, industrialized nations have faced a new problem, the contamination of water by emerging contaminants, such as pharmaceuticals and personal care products (PPCPs). A method based on solid-phase extraction (SPE) and liquid chromatography with electrospray ionization source tandem mass spectrometry was developed and validated for the determination of nimesulide, amitriptyline, enalapril, glibenclamide, haloperidol and methylparaben in water samples. In the study of SPE, a 2v5-1 fractional factorial design was used as a tool for the selection of the most significant variables in the extraction efficiency of the analytes under study. The limits of detection and quantification ranged from 0.01 to 0.2 µg L-1 and 0.05 to 1.0 µg L-1, respectively. Good linearity was obtained by a correlation coefficient (r) > 0.99 for all compounds. Recoveries ranged from 65 and 120% with relative standard deviation (RSD) lower than 20%. The method was applied to the determination of PPCPs in samples of surface and drinking water for three months. PPCPs were detected at µg L-1 levels.

A produção agrícola geralmente está associada ao uso de agrotóxicos. Suas características físico-químicas, condições do solo e do ambiente determinam seu destino, assim como o seu potencial de contaminação dos mananciais hídricos. Com o intuito de prever a contaminação do ambiente por agrotóxicos, critérios e modelos matemáticos são utilizados para avaliar o risco de contaminação das águas subterrâneas e superficiais. Diante do exposto, este trabalho teve por objetivo estimar a probabilidade de contaminação de águas subterrâneas e superficiais por agrotóxicos, baseado nas suas características físico-químicas, com auxílio de modelos e parâmetros matemáticos preexistentes. Para análise do risco de contaminação de águas superficiais, foi utilizado o método de Goss, o qual é dividido em dois grupos: potencial de transporte de agrotóxicos dissolvidos em água e adsorvido ao sedimento. Os critérios utilizados para avaliar o potencial de lixiviação foram os sugeridos pela Agência de Proteção Ambiental dos EUA e pelo Índice de GUS. Os resultados obtidos neste trabalho permitem concluir que o uso de modelos de predição do comportamento de agrotóxicos é útil para se obter uma estimativa do risco de contaminação ambiental, pois alguns resultados de monitoramentos confirmam a tendência do comportamento de certos agrotóxicos no ambiente.

Agricultural production is generally associated with the use of pesticides, their physicochemical characteristics, soil conditions and the environment will determine their fate, as well as the potential for contamination of water bodies. In order to predict environmental contamination by pesticides, parameters and mathematical models are utilized to assess the risk of contamination of groundwater and surface water. For this reason, the objective of this study was estimate the probability of contamination of groundwater and surface waters by pesticides based on their physicochemical characteristics with the aid of preexisting mathematical models and parameters. To analyze the risk of surface water contamination, the Goss method was used, which as composed by two groups: pesticide potential transport dissolved in water and adsorbed to the sediment. The parameter used to evaluate the leaching potential were those suggested by the US Environmental Protection Agency (EPA) and the GUS Index. The results obtained allow to conclude that the use of models to predict the behavior of pesticides is useful to obtain an estimate of the risk of environmental contamination, as some monitoring results confirm the tendency of the behavior of certain products into the environment.

Neste trabalho, é descrito um método para determinação dos agrotóxicos 2,4-D, diurom e fipronil em mel de cana-de-açúcar. O método QuEChERS foi empregado para extração e a quantificação foi realizada por cromatografia líquida de alta eficiência acoplada ao detector por arranjo de diodos (HPLC-DAD) e cromatografia líquida acoplada à espectrometria de massas sequencial com fonte de ionização por eletronebulização(LC-ESI-MS/MS). Após a otimização dos parâmetros de extração e determinação dos agrotóxicos, o método foi validado avaliando-se a curva analítica, linearidade, limites de detecção e quantificação, precisão (repetibilidade) e exatidão (recuperação). Devido à ocorrência do efeito de matriz, a quantificação foi realizada com os padrões analíticos preparados no extrato branco da matriz. O método apresentou limites de detecção na faixa de 0,016-0,1 mg kg-1 por HPLC-DAD e de 0,00016-0,0008 mg kg-1 por LC-ESI-MS/MS. O método foi empregado na determinação de agrotóxicos em mel de cana-de-açúcar.

This paper aims at describing a method to determine the pesticides 2,4-D, diuron and fipronil in sugarcane honey. The QuEChERS method was employed for extraction and the quantification was carried out by high performance liquid chromatography coupled with diode array detector (HPLC-DAD) and liquid chromatography-tandem mass spectrometry with electrospray ionization source (LC-ESI-MS/MS). After the optimization of the extraction parameters and the determination of the pesticides, the method was validated by evaluating the analytical curve, linearity, limits of detection and quantification, precision (repeatability) and accuracy (recovery). Due to the occurrence of matrix effect, the quantification was performed using the analytical standards prepared in the blank matrix extract. The method provided limits of detection in the range of 0.016-0.1 mg kg-1 by HPLC-DAD and 0.00016-0.0008 mg kg-1 by LC-ESI-MS/MS. The method was applied to the determination of pesticides in sugarcane honey.

Neste trabalho, foi desenvolvido e validado um método analítico baseado na extração em fase sólida (SPE) e cromatografia líquida acoplada a espectrometria de massas em tandem (LC-APCI-MS/MS) para a determinação e confirmação de cinco fármacos em amostras de água. Os limites de detecção (LOD) variaram de 0,053 a 0,53 µg L-1 e os limites de quantificação (LOQ) de 0,16 a 1,6 µg L-1. Foi obtida boa linearidade com r > 0,99 para todos os compostos. As recuperações dos compostos variaram de 70 a 120%, com desvios padrão relativos (RSD) menores que 20% para todos. Através do monitoramento de reações múltiplas (MRM), foram selecionadas duas transições diferentes íon precursor-íon produto para cada fármaco.

In this work, an analytical method based on solid phase extraction (SPE) and liquid chromatography tandem mass spectrometry (LC-APCI-MS/MS) was developed and validated for the determination and confirmation of five pharmaceuticals in water samples. The limits of detection (LOD) ranged from 0.053 to 0.53 µg L-1 and the limits of quantification (LOQ) from 0.16 to 1.6 µg L-1. Good linearity was obtained with r > 0.99 for all compounds. The recoveries of the compounds ranged from 70 to 120% with relative standard deviations (RSD) below 20% for all. Through multiple reactions monitoring (MRM) two different transitions, precursor ion-product ion, were selected for each pharmaceutical.

The determination of pesticide residues in water samples by Liquid Chromatography require sample preparation for extraction and enrichment of the analytes with the minimization of interferences to achieve adequate detection limits. The Solid Phase Extraction (SPE), Solid Phase Microextraction (SPME), Stir Bar Sorptive Extraction (SBSE) and Dispersive Liquid-Liquid Microextraction (DLLME) techniques have been widely used for extraction of pesticides in water. In this review, the principles of these sample preparation techniques associated with the analysis by Liquid Chromatography with Diode Array Detection (LC-DAD) or Mass Spectrometry (LC-MS) are described and an overview of several applications were presented and discussed.

The objective this study was to monitor pesticide residues in groundwater at three different times and in seven regions producing rice in southern Brazil, in the 2007/08 season. Imazethapyr and fipronil were found in all regions studied. All groundwater samples from the Planície Costeira Interna to Lagoa dos Patos and Santa Catarina contained at least one pesticide. The lowest number of contaminated samples were detected in the Southern region. The highest frequency of contaminated samples was found after drainage of the rice fields. Only fipronil exceeded limits of potability, in 27% of samples, according European Community criteria.

An evaluation of the pesticides extraction from onion using a modern sample preparation method (QuEChERS) and determination by liquid chromatography tandem mass spectrometry was carried out. All the calibration curves showed r>0.99. The recoveries ranged between 61.8 and 120.0% with relative standard deviation lower than 20% for all compounds. Due to the occurrence of matrix effect, the quantification was performed using matrix-matched calibration. The limits of quantification of the method were between 0.0005 and 0.05 mg kg-1. The method shows the advantages of not require the clean-up step and consume low volume of organic solvents, decreasing time, costs and residues.