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.

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.

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.

O sistema de degradação utilizando ferro metálico e peróxido de hidrogênio (reação de Fenton) foi empregado para a degradação do herbicida diurom. Visando obter as melhores condições de degradação, foram otimizados parâmetros que influenciam no processo, como pH, concentração de peróxido de hidrogênio (H2O2) e quantidade de ferro. A degradação do herbicida foi acompanhada por cromatografia líquida com detecção por arranjo de diodos (CLAE-DAD) e cromatografia líquida com detecção por espectrometria de massas sequencial (LC-ESI-MS/MS), além da determinação de carbono orgânico total (COT). Nas melhores condições de degradação, pH = 2,5; 2 g de ferro e 2 mmol L-1 de H2O2, uma solução aquosa de diurom comercial (10 mg L-1), alcançou valores não detectáveis ao tempo de 10 min, para diurom e para o metabólito monitorado, 3,4-DCA. Ainda os valores de COT foram reduzidos, chegando a valores menores que 5 mg L-1, mostrando a eficiência e rapidez do sistema.

A degradation system using metallic iron and hydrogen peroxide (Fenton reaction) was employed for the degradation of the diuron herbicide. In order to obtain the maximum degradation the main conditions such as pH, hydrogen peroxide concentration and iron amount, were optimized. Herbicide degradation was evaluated by liquid chromatography with diode array detection (HPLC-DAD) and liquid chromatography tandem mass spectrometric detection (LC-ESI-MS/MS) and total organic carbon analysis (TOC). In the best degradation condition, pH = 2.5, 2 g of iron and 2 mmol L-1 of hydrogen peroxide, after 10 min a commercial diuron solution (10 mg L-1) had no detection values for diuron and its metabolic, 3,4-dichloroaniline (3,4-DCA). The TOC was reduced to values lower than 5 mg L-1 showing the efficiency of the system.

Um método analítico baseado na extração em fase sólida e cromatografia líquida acoplada à espectrometria de massas tandem (LC-ESI-MS-MS) foi desenvolvido e validado para a determinação e confirmação de dezoito agrotóxicos (herbicidas, inseticidas e fungicidas) e dois metabólitos em amostras de água. Os limites de detecção variaram de 0,4 a 40,0 ng L-1 e os limites de quantificação de 4,0 a 100,0 ng L-1. Foi obtida boa linearidade, com r² > 0,99 para todos os compostos. As recuperações, para 95% dos compostos, variaram de 70 a 120%, com RSDs menores que 21% para todos. Através do monitoramento de reações múltiplas (MRM), foram selecionadas duas diferentes transições íon precursor-íon produto para cada agrotóxico. A metodologia proposta pode ser usada para a determinação de resíduos de agrotóxicos em águas de superfície e potável, em concordância com a Lei n° 518 do Ministério da Saúde, Brasil, e com os parâmetros da União Européia para água potável (Directive 98/83/EC).

An analytical method using solid-phase extraction and liquid chromatography coupled to electrospray ionization tandem mass spectrometry (LC-ESI-MS-MS) was developed and validated for the determination and confirmation of eighteen polar pesticides (herbicides, insecticides and fungicides) and two metabolites in water samples. The limits of detection varied between 0.4-40.0 ng L-1 and the limits of quantification between 4.0-100.0 ng L-1. Good linearity with r² > 0.99 for all compounds was obtained. The recovery for 91% of the accuracy experiments varied from 70 to 120%, with RSD below 21% for all. Through multiple reaction monitoring (MRM) two different precursor ion-product ion transitions were selected for each pesticide. The proposed methodology can be used for the convenient and effective determination of pesticide residues in surface and drinking waters in accordance with Law No. 518 ofthe Ministry of Health, Brazil, and the European Union Directive on drinking water quality (98/83/EC).

Resíduos de quatro agrotóxicos foram determinados durante um ano em águas de poços de uma área agrícola no Sul do Brasil. Os métodos para a separação, identificação e quantificação dos compostos incluíram cromatografia líquida de alta eficiência com detecção por arranjo de diodos (HPLC-DAD) e cromatografia líquida acoplada à espectrometria de massas (LC-ESI-MS/MS). Uma etapa de pré-concentração baseada na extração em fase sólida com cartuchos de 200 mg de C18 foi realizada. Todos os parâmetros analíticos ficaram de acordo com os limites sugeridos para a validação de métodos cromatográficos. Os limites de quantificação para o método, considerando um fator de pré-concentração de 250 vezes, foram 0,2 μg L-1 para todos os analitos por HPLC-DAD, 4,0 ng L-1 para o clomazona, carbofurano e tebuconazol e 40,0 ng L-1 para o 2,4-D por LC-ESI-MS/MS. Nas amostras de águas subterrâneas, o 2,4-D não foi detectado e o carbofurano, clomazona e tebuconazol apresentaram concentrações que variaram entre 0,25 e 10,40 μg L-1, 0,20 e 0,82 μg L-1, e 0,20 e 4,16 μg L-1, respectivamente. Os métodos mostraram-se adequados para a determinação de agrotóxicos em águas subterrâneas.

Residues of four pesticides in groundwaters were surveyed during one year in an agricultural area in southern Brazil. The methods for separation, identification and quantification of the compounds included high-performance liquid chromatography with diode array detection (HPLC-DAD) and liquid chromatography with electrospray interface tandem mass spectrometry (LC-ESI-MS/MS). A pre-concentration step based on solid-phase extraction with 200 mg C18 cartridges was applied. All the analytical parameters were within the limits suggested for the validation of chromatographic methods. The LOQs for the methods, considering the 250-fold pre-concentration step, were 0.2 μg L-1 for all pesticides by HPLC-DAD, 4.0 ng L-1 for clomazone, carbofuran and tebuconazole and 40.0 ng L-1 for 2,4-D by LC-ESI-MS/MS. In groundwater samples, 2,4-D was not detected, and carbofuran, clomazone and tebuconazole were detected in concentrations ranging from 0.25 to 10.40 μg L-1, from 0.20 to 0.82 μg L-1 and from 0.20 to 4.16 μg L-1, respectively. The methods proved to be adequate for the analysis of pesticides in groundwaters.

Onion (Allium cepa) is being studied as a potential anticancer agent, but little is known regarding its effect in multidrug resistance (MDR) cells. In this work, the cytotoxicity of crude onion extract (OE) and fractioned extract (aqueous, methanolic and ethyl acetate), as well as some onion compounds (quercetin and propyl disulfide) were evaluated in Lucena MDR human erythroleukemic and its K562 parental cell line. The capacity of OE to induce apoptosis and/or necrosis in these cells, the possible participation of oxidative stress and DNA damage were also assessed. Similar sensitivities were obtained for both tumoral cells, however only OE caused significant effects in the cells. In K562 cells, a significant increase of apoptosis was verified while the Lucena cells experienced a significant increase of necrosis. An antioxidant capacity was verified for OE discarding oxidative damage. However, OE provoked similar significant DNA damage in both cell lines. Thus, the OE capacity to overcome the MDR phenotype suggests anti-MDR action of OE.

Neste trabalho, um método para determinação dos agrotóxicos carbofurano, clomazona, 2,4-D e tebuconazol em águas subterrâneas é descrito. O método utiliza a Extração em Fase Sólida (EFS) com cartuchos de C18 e quantificação por Cromatografia Líquida de Alta eficiência com Detector de Arranjo de Diodos (CLAE-DAD). Após a otimização dos parâmetros de extração e separação dos compostos, o método foi validado avaliando-se curva analítica, linearidade, limites de detecção e quantificação, precisão e exatidão (recuperação). O método apresentou recuperações médias de 87,9% e 96,9%, para a repetibilidade e precisão intermediária, respectivamente, com RSD de 0,8 a 20,7% para todos os compostos. O método será empregado na determinação de agrotóxicos em águas subterrâneas com um limite de quantificação de 0,2 μg L-1.

A method is described for the determination of the pesticides carbofuran, clomazone, 2,4-D and tebuconazole in groundwaters. The method involves solid phase extraction (SPE) with C18 cartridges and quantification by high performance liquid chromatography with diode array detector (HPLC-DAD). After the optimization of the extraction and separation parameters, the method was validated by evaluating the analytical curve, linearity, limits of detection and quantification, precision and accuracy (recovery). The method presents an average recovery of 87.9% and 96.9%, in repeatability and intermediate precision conditions, respectively, with adequate precision (RSD from 0.8 to 20.7%), for all compounds. The method will be applied to determine pesticides in groundwater samples with limit of quantification of 0.2 μg L-1.