Abstract Background Phytoremediation is a technique used in soils contaminated with residual herbicides, such as tebuthiuron. However, the herbicide presence in the soil and plant matrices are not generally quantified. Objective This study aimed to select plant species to evaluate the phytoremediation of 14C-tebuthiuron by showy rattlepod (Crotalaria spectabilis), sorghum (Sorghum bicolor), radish (Raphanus sativus), peanut (Arachis hypogaea), and alfalfa (Medicago sativa) in herbicide-contaminated soil. Methods The selection of the five herbicide phytoremediation plants was with the application of five rates of tebuthiuron (300, 600, 1,200, 2,400, and 4,800 g a.i. ha-1) and compared to a control. Peanuts and sorghum (herbicide-tolerant plants) were sown in soil contaminated with tebuthiuron (600 g a.i. ha-1) applied through a working solution containing 17.47 kBq of 14C-tebuthiuron. The total of herbicide was analyzed in the soil and plant at three phenological stages. Results Showy rattlepod, radish, and alfalfa were sensitive to the herbicide even at the lowest application rate. Sorghum was tolerant to the herbicide up to 600 g ha-1 with the application of 1,200 g ha-1, there was 80% injury; peanut was tolerant even at the highest rate (4,800 g ha-1) with only 40% injury. Peanut and sorghum were able to phytoremediate the soil, although, peanut was more efficient in decreasing tebuthiuron contamination by 76%, while sorghum reduced at by 45% at 3rd phenological stage. Conclusions Thus, both plants can be recommended in succession/rotation with crops that had tebuthiuron applied from pre-emergence weed control.

Abstract The presence of steroid hormones in lake waters causes contamination of aquatic ecosystems, which may cause endocrine alterations in the organisms that inhabit them. Moreover, many of these waters are purified and distributed to populations located around the lake. Therefore, these effects could be repeated in humans consuming the water. This study reports the presence of steroid hormone residues in the waters of the inner bay of Lake Titicaca and drinking water in the city of Puno (Peru). The solid phase extraction method was used for sample preparation, and the analyses were developed in an HPLC-DAD system. Results show maximum concentrations of steroid hormones estrone (E1) 1.56, 17 β- estradiol (E2) 2.27, 17 α- ethinylestradiol (EE2) 13. 88 ng L-1 respectively. These concentrations vary at the different monitoring points, and their presence could cause ecotoxicological effects to the endemic aquatic biota that inhabit this part of the lake. At the same time they also could affect the health of the human population that consumes this water.

Resumen La presencia de hormonas esteroides en las aguas de los lagos provoca la contaminación de los ecosistemas acuáticos, lo que puede provocar alteraciones endocrinas en los organismos que los habitan. Además, muchas de estas aguas se depuran y distribuyen a las poblaciones ubicadas alrededor del lago; por tanto, estos efectos podrían repetirse en los seres humanos que consumen estas aguas. Este estudio reporta la presencia de residuos de hormonas esteroides en las aguas del interior de la bahía del lago Titicaca y agua potable en la ciudad de Puno (Perú). Para la preparación de la muestra se utilizó el método de extracción en fase sólida y los análisis se desarrollaron en un sistema HPLC-DAD, laboratorio CENA- USP- Brasil. Los resultados muestran concentraciones máximas de hormonas esteroides estrona (E1) 1,56, 17 β-estradiol (E2) 2,27, 17 α-etinilestradiol (EE2) 13. 88 ng L-1 respectivamente. Estas concentraciones varían en los diferentes puntos de monitoreo, y su presencia podría ocasionar efectos ecotoxicológicos a la biota acuática endémica que habita esta parte de este lago; al mismo tiempo también podrían afectar la salud de la población humana que consume esta agua.

ABSTRACT Lake Titicaca is an important water resource and the ecological balance of the Peruvian-Bolivian Andean plateau depends on it. At present, it is being disturbed by poor water resource management practices, which is why persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) were monitored in sediments from 13 sampling stations in the Inner Bay of Lake Titicaca (Puno, Peru). The samples were lyophilized and stored at -70°C for further analysis. For the validation of the analytical method, the following parameters were considered: recovery, repetition and uncertainty of all the compounds studied. The POPs were determined by gas chromatography coupled to an electron capture detector, and the presence of β-BHC, 0.018 μg/g; o,p´-DDE, 0.0011 μg/g; dicofol 0.0065 μg/g and endosulfan sulfate 0.0061 μg/g were detected. On the other hand, PAHs were determined by liquid chromatography coupled to a fluorescence detector, confirming the presence of naphthalene, 0.058 μg/g; pyrene, 0.039 μg/g; benzo(a)anthracene, 0.571 μg/g and chrysene, 0.033 μg/g. The presence of POPs and PAHs evidences an environmental risk for the species that inhabit the ecosystem of this lake.

RESUMEN El Lago Titicaca es un importante recurso hídrico y de él depende el equilibrio ecológico de la meseta andina peruano-boliviana. En la actualidad, está siendo perturbada por las malas prácticas de gestión de los recursos hídricos, razón por la cual los contaminantes orgánicos persistentes (COP) y los hidrocarburos aromáticos policíclicos (HAP) fueron monitoreados en los sedimentos de 13 estaciones de muestreo en el interior de la bahía del Lago Titicaca (Puno, Perú). Las muestras fueron liofilizadas y almacenadas a -70°C para su posterior análisis. Para la validación del método analítico se consideraron los siguientes parámetros: recuperación, repetición e incertidumbre de todos los compuestos estudiados. Los COPs fueron determinados por cromatografía de gases acoplada a un detector de captura de electrones, y se detectó la presencia de β-BHC, 0.018 μg/g; o,p´-DDE, 0.0011 μg/g; dicofol 0.0065 μg/g y sulfato de endosulfán 0.0061 μg/g. Por otra parte, los HAP se determinaron mediante cromatografía líquida acoplada a un detector de fluorescencia, confirmando la presencia de naftalina, 0.058 μg/g; pireno, 0.039 μg/g; benzo(a)antraceno, 0.571 μg/g y criseno, 0.033 μg/g. La presencia de COPs y HAPs evidencia un riesgo ambiental para las especies que habitan el ecosistema de este lago.

ABSTRACT The application of sewage sludge (SS) in agriculture is a practice used worldwide, and it is commonly applied in sugarcane to supply nutrients, with beneficial effects on crop productivity and soil; but SS can increase sorption and decrease desorption of herbicides. However, in tropical soils such as in Brazil, there are no studies regarding the behavior of pre-emergent herbicides, mainly aminocyclopyrachlor and mesotrione, in SS-amended soil. The aim of the present study was to determine the effect of municipal SS applied in agriculture on the sorption–desorption of aminocyclopyrachlor and mesotrione in clay soil. Aminocyclopyrachlor (pyrimidine-2-14C-aminocyclopyrachlor) and mesotrione (cyclohexane-2-14C-mesotrione) sorption–desorption was evaluated using a batch equilibrium method. Soil was amended at 0% (control – unamended), 0.1%, 1%, and 10% (w∙w–1) of air-dried SS corresponding to 1.2, 12, and 120 t∙ha–1. The Freundlich Kf sorption values of aminocyclopyrachlor and mesotrione were similar for all treatments, ranging from 1.07 to 1.45 and 3.48 to 4.25 µmol (1–1/n) L1/n∙kg–1, respectively. Overall, the lowest Kd sorption value of these herbicides was reported for SS-amended soil (1%), while in the SS-amended soil (10%) it was higher than unamended soil. The H value for aminocyclopyrachlor was ~1 (no hysteresis) and for mesotrione was on average 0.4 (hysteresis occurring). In conclusion, the present study indicates that SS applied in any crop to supply nutrients can slightly affect the sorption–desorption of aminocyclopyrachlor and mesotrione, but this small difference does not affect the bioavailability of these herbicides for weed control.

ABSTRACT Microbial adaptation may occur in surface soils under agricultural uses exposed to herbicides. However, little is known about herbicide mixture effects in the soil, especially in tropical regions like Brazil. The aim of this study was to evaluate glucose mineralization in soils of contrasting textures (sandy clay and sandy loam) from areas cultivated with maize under application of S-metolachlor, terbuthylazine and mesotrione, alone and in a mixture. The methodology was established according to the soil microorganisms: carbon transformation test with 14C-glucose solution (D-[U-14C] glucose) in biometric flasks. After the addition of 14C-glucose, the amount of 14C in cumulative CO2 of microbial respiration was measured several times during the 28-day incubation. For unamended soil control (without herbicide), microbial activity followed a similar behavior to amended soil with herbicides in total 14CO2 released and accumulated, ranging from 23 to 27%. Overall, mineralization constant rate (k) values for all treatments were also similar, with an average value of 0.0038% CO2.d–1. Consequently, mineralization half-life times (MT50) were from 173 to 198 d. Microbial respiration for all treatments was slightly higher in the sandy clay compared with sandy loam soil; although soil samples with application of herbicides (alone and in a mixture) did not show decreased basal microbial respiration or mineralization rates of glucose. To corroborate these findings, additional research with different organic substrates and in cultures with different applications of herbicides are needed to prove the non interference of these herbicides on the microbial respiration in the soil.

ABSTRACT Due their physical end chemical properties, organochlorine pesticides (OCPs) have been occured the contamination the environment and food chain. The consume of this products at low concentration dose represent a potential hazards to human health. The QuEChERS method was adjusted and used for the determination of 12 organochlorine pesticides (α- BHC, β - BHC, heptachlor, dicofol, endosulfan lacton, OP DDD, α - endosulfan, OP DDE, PP DDE, β - endosulfan, PP DDD, endosulfan sulfate) residues in 36 strawberries samples from three markets of the Piracicaba/ Sao Paulo - Brazil, during the period of October 2010 until September 2011. The method involved extraction with ethyl acetate, solid-liquid partition with MgSO4 and CH3COONa followed by dSPE clean up with PSA sorbent. Analyses were carried out with GC-μECD equipment. A HP-5 30 m x 0.32mm x 0.25 μm column was used. The method was validated using a strawberry sample without pesticides residues (blank), spiked at 0.01 and 0.1 mg kg-1; the average recovery by the method varied between 72.9 to 120% with RSD% < 9.6%. The method showed linearity r² ≥ 0.99 and the LOQ ranged from 0,001 to 0.01 mg kg-1. It could be concluded that QuEChERS method used with GC-μECD is an alternative to determine organochlorine pesticides in strawberries. The results obtained indicate that this method sensitive and has no matrix effect. The method showed six of the samples analyzed have contamination by endosulfan sulfate at the concentrations of 0.003 to 0.02 mg kg-1

RESUMEN Debido a sus propiedades físicas y químicas los plaguicidas organoclorados han contaminado el medio ambiente y la cadena alimentaria. El consumo de estos productos en bajas concentraciones es un peligro potencial para la salud humana. El método QuEChERS fue ajustado y utilizado para la determinación de residuos de 12 plaguicidas organoclorados (α- BHC, β - BHC, heptacloro, dicofol, endosulfan lacton, OP DDD, α - endosulfan, OP DDE, PP DDE, β - endosulfan, PP DDD, endosulfan sulfato) en 36 muestras de fresas de tres mercados en la ciudad de Piracicaba / Sao Paulo - Brasil, durante el período de octubre de 2010 a septiembre de 2011. El método consiste en la extracción con acetato de etilo, partición sólida líquida con MgSO4 y CH3COONa seguido por clean up por dSPE con PSA. Los análisis fueron realizados con un equipo GC-µECD utilizando una columna HP-5 30 m x 0,32 mm x 0,25 µm. El método fue validado usando una muestra de fresa sin residuos de agrotóxicos (blanco), fortificado a 0,01 y 0,1 mg kg-1; la recuperación varió entre 72,9 a 120 % con RSD% < 9,6%. El método mostro linealidad r² ≥ 0,99 y los LOQs variaron entre 0,001 a 0,01 mg kg-1. Los resultados obtenidos indican que el método es sensible y no existe efecto matriz. Podemos concluir que el método QuEChERS utilizando GC-µECD es una alternativa para la determinación de pesticidas organoclorados en fresas. El método mostró que seis muestras presentan contaminación por endosulfan sulfato en las concentraciones 0,003 a 0,02 mg kg-1

RESUMO Devido às propriedades físico-químicas dos agrotóxicos organoclorados, têm ocorrido contaminação do ambiente e da cadeia alimentar. O consumo destes produtos em baixas concentrações representa um perigo potencial à saúde humana. O método QuEChERS foi ajustado e usado para a determinação de resíduos de 12 agrotóxicos organoclorados (α- BHC, β - BHC, heptacloro, dicofol, endosulfan lacton, OP DDD, α - endosulfan, OP DDE, PP DDE, β - endosulfan, PP DDD, endosulfan sulfato) em 36 amostras de morango de três varejões na cidade de Piracicaba/São Paulo - Brasil, durante o período de outubro de 2010 até setembro de 2011. O método envolve extração com acetato de etila, partição sólida líquida com MgSO4 e CH3COONa seguido por clean up por dSPE com PSA. As análises foram realizadas com um equipamento GC-µECD utilizando uma coluna HP-5 30 m x 0,32 mm x 0,25 µm. O método foi validado usando uma amostra de morango sem resíduos de agrotóxicos (branco), fortificado a 0,01 e 0,1 mg kg-1; a recuperação média do método variou entre 72,9 a 120 % com RSD% < 9,6%. O método mostrou linearidade r² ≥ 0,99 e os LOQs variaram entre 0,001 a 0,01 mg kg-1. Os resultados obtidos indicam que o método é sensível e não existe efeito matriz. Pode-se concluir que o método QuEChERS utilizando GC-µECD é uma alternativa para determinar resíduos de pesticidas organoclorados em morango. O método mostrou que seis das amostras analisadas apresentaram contaminação por endosulfan sulfato nas concentrações de 0,003 a 0,02 mg kg-1

RESUMO O objetivo deste trabalho foi avaliar a qualidade da água do Ribeirão Samambaia (São Pedro, São Paulo, Brasil) utilizando parâmetros físicos e químicos, índice de estado trófico (IET) e ensaio ecotoxicológico com Daphnia magna. De janeiro a dezembro de 2011, amostras de água foram coletas mensalmente à montante e à jusante de São Pedro e dentro da cidade, e expostas a D. magna em laboratório durante 48 horas para avaliar efeitos sobre sua mobilidade. Condutividade, fenóis, oxigênio dissolvido, demanda bioquímica de oxigênio, surfactantes, pH e IET foram mensurados. Valores dos cinco primeiros parâmetros demonstraram baixa qualidade da água à jusante da cidade. Valores de clorofila-a estiveram dentro do permitido pela legislação ambiental brasileira e, dessa forma, o IET das águas do Ribeirão Samambaia foi classificado como ultraoligotrófico para a maioria dos locais e meses amostrados. Amostras de água coletadas de janeiro a abril à jusante de São Pedro foram tóxicas para D. magna. De acordo com as características físicas e químicas e o ensaio ecotoxicológico, conclui-se que o Ribeirão Samambaia possui baixa qualidade da água após a cidade de São Pedro.

ABSTRACT The goal of this study was to evaluate the water quality of Samambaia Creek (São Pedro, São Paulo, Brazil) through physical chemical parameters, trophic state index (TSI) and ecotoxicological assay with Daphnia magna. From January to December 2011 water samples were monthly collected from upstream, downstream and inside the São Pedro city, and exposed to D. magna in laboratory for 48 hours to evaluate mobility effects. Conductivity, phenols, dissolved oxygen, biochemical oxygen demand, surfactants, pH, and TSI were measured. Values of the first five parameters showed low water quality downstream of the city. Chlorophyll a values were within the range permitted by the Brazilian environmental legislation and thus the TSI in Samambaia Creek was classified as ultra-oligotrophic for most sites and months. Water samples collected from January to April downstream of São Pedro were toxic to D. magna. The physical chemical analysis and the toxicity test indicate low quality of water from Samambaia Creek downstream the city of São Pedro.

In this study, the monitoring of pesticide residues, which show potential for environmental contamination, in center-pivot irrigated areas in the Brazilian cerrado, was performed. The pesticides monitored were acephate, atrazine, azoxystrobin, buprofezin, carbofuran, cyproconazole, chlorpyrifos, difenoconazole, diuron, imidacloprid, malathion, methamidophos, metolachlor, metribuzin, monocrotophos, monuron, thiamethoxam, and triazophos. Surface water samples were collected upstream and downstream of Tijunqueiro dam. The subsurface water in piezometric wells was drilled in the surroundings of the irrigated area; fish and sediment were collected in the dam. The technique of solid phase extraction (SPE) was used for the extraction of water samples, the matrix solid phase dispersion (MSPD) for the sediment samples and QuEChERS (quick, easy, cheap, effective, rugged and safe) for the fish samples. The multiresidue methods used were accurate and precise for most pesticides monitored by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Atrazine was detected in two of the subsurface water samples.

Tomatoes are widely consumed and most often without cooking, therefore it is important to estimate the reduction of residues using simple washing procedures. An experiment was carried out to evaluate the effects of household processing such as: washing with water, washing with 10% of vinegar solution and washing with 10% of sodium bicarbonate solution on pesticide residue levels of acetamiprid, azoxystrobin, diflubenzuron, dimethoate, fipronil, imidacloprid, procymidone and thiamethoxam, in spiked tomato samples. The amount of residue remaining in the peel and pulp was also investigated. The pesticide residues were monitored using the quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction and analysed by liquid chromatography tandem mass spectrometry method (LC-MS/MS) in dynamic multiple-reaction monitoring mode (DMRM). The effect of the number of washing treatments (n = 3) and control, with six replicates, differed significantly for all pesticides evaluated (n = 8), but despite washing, fipronil residues were not removed from the tomato samples. Overall, washing with water or other solutions, and peeling before consumption are shown to reduce pesticide residues in tomatoes.

RESUMO: O imazaquin é um herbicida utilizado intensivamente no Brasil para controlar plantas daninhas associadas principalmente a cultura da soja. O presente trabalho teve como objetivos estudar a mobilidade e a lixiviação do imazaquin em solos com diferentes características. Em ambos os experimentos o delineamento estatístico foi inteiramente casualizado com três repetições. Estudou-se a mobilidade do imazaquin em Latossolo Vermelho Eutrófico (textura muito argilosa), Nitossolo Háplico Eutrófico (textura média argilosa), Argissolo Vermelho Amarelo Eutrófico (textura média argilosa) e Neossolo Quartzarênico Órtico (textura arenosa). Para a obtenção do coeficiente de mobilidade (Rf) uma solução de 14C-imazaquin com atividade de 304,75 Bq/µL foi aplicado em placas contendo os diferentes solos. Todos os valores de Rf variaram entre 0,803 e 1, indicando que o herbicida possui alta mobilidade para todos os solos. No estudo de lixiviação foram utilizados os solos classificados como Latossolos Vermelhos e que diferiam quimicamente. O herbicida imazaquin (14C Imazaquin + produto técnico) foi aplicado na dose recomendada (161 g i.a ha-1), diretamente sobre a superfície das amostras de solo que foram previamente empacotadas em colunas. Posteriormente, foi feita simulação de chuva de 200 mm. A maior parte de radioatividade do imazaquin foi retida nas camadas de 0 a 10 cm nos dois solos LVe, sendo que no solo com maior pH uma pequena % de radioatividade foi notada até a camada de 15-20 cm. O herbicida imazaquin tem maior mobilidade em solos com baixo teor de matéria orgânica e de argila e em solos com alto pH.

ABSTRACT: Imazaquin is an herbicide widely used in Brazil to control weeds associated with the soybean crop. This work aimed to study the mobility and leaching of imazaquin in soils with different characteristics. In both experiments, a completely randomized block design was used; with tree replicates. We study the mobility of imazaquin in Red Eutrophic Latosol, clayey; Alfisol Haplic Eutrophic, medium texture; Alfissol Eutrophic, medium texture; and Orthic Psament, sandy texture. To obtain the mobility rate (Mr), a solution of 14C-imazaquin with the activity of 304,75 Bq/mL was applied to plates containing different soils. All Mr values range between 0.803 and 1, indicating that imazaquin has a relevant mobility in our soils. In the leaching study, the soils were classified as Rhodic and differed chemically. The herbicide imazaquin (14C + imazaquin technical product) was applied to the highest recommended dose ( 161 g a.i. ha-1), directly on the soil surface of each column. After that, was done a rainfall simulation of 200 mm. Nearly 100% of the herbicide was in the 0-10 cm layer, however, the soil with higher pH, the herbicide was distributed to 15-20 cm depth. The herbicide imazaquin has greater mobility in soils with low organic matter and clay and soils with high Ph.

Atividades antrópicas causam grandes impactos em ambientes aquáticos, provocando alterações na biodiversidade e no ambiente. Na tentativa de determinar níveis de poluição foram definidos parâmetros físicos e químicos, índice de estado trófico e testes de toxicidade com organismos. O Rio Piracicaba é um importante corpo d'agua que recebe despejos de xenobióticos de origem agropecuária, industrial e doméstica. Estes poluentes são lançados de forma direta ou são provenientes de córregos que deságuam nesse rio, como o córrego Itapeva. Os objetivos deste trabalho foram analisar o fator de toxicidade para Daphnia magna (FTD), índice de estado trófico (IET), pH, condutividade, temperatura e oxigênio dissolvido no Rio Piracicaba e córrego Itapeva a partir de uma coleta mensal nos meses de maio a agosto de 2011. No Rio Piracicaba não foi encontrada toxicidade, e nos meses de maio, junho e agosto, os FTD foram de 1, 8 e 1, respectivamente. A IET variou de mesotrófico a eutrófico no Rio e no Córrego de ultraoligotrófico a mesotrófico. A condutividade média para o Córrego Itapeva foi de 479,5 μS.cm-1 e para o Rio Piracicaba foi de 219,8 μS.cm-1. O oxigênio dissolvido no Rio Piracicaba variou de 6,89 a 11,36 mg.L-1 e no Córrego Itapeva de 0,92 a 6,31 mg.L-1. Com base nos resultados, ambos os corpos hídricos apresentavam-se no momento como eutróficos, e o Córrego do Itapeva foi classificado como impróprio para a manutenção da vida aquática.

Anthropogenic activity has a great impact on aquatic environments, causing changes in biodiversity and the environment. In an attempt to determine pollution levels, we established physicochemical parameters, a trophic state index and toxicity assays. The Piracicaba River is an important water body that receives xenobiotic waste from industry, domestic activities and agriculture. These pollutants are released directly into the river or by streams like Itapeva Stream, which discharges into the river. The goals of this work were to analyze the toxicity factor for Daphnia magna (TFD), trophic state index (TSI), pH, conductivity, temperature and dissolved oxygen in the Piracicaba River and in the Itapeva Stream from one monthly collection in the months of May, June and August 2011. In the Piracicaba River was not found toxicity, while in May, June and August the TFD was 1, 8 and 1, respectively. The TSI varied from mesotrophic to eutrophic in the river and in the stream from ultraoligotrophic to mesotrophic. The medium of conductivity for the Itapeva Stream was 479.5 µS.cm-1 and for the Piracicaba River was 219.8 µS.cm-1. The dissolved oxygen in the Piracicaba River varied from 6.89 to11.36 mg.L-1 and in the Itapeva Stream from 0.92 to 6.31 mg.L-1. Based upon the results, both hydric bodies were eutrophic, and the Itapeva Stream was classified as unsuitable for maintaining aquatic life.

An environmental impact study was conducted to determine the Piracicamirim's creek water quality in order to assess the influence of effluents from a sugar industry in this water body. For this, toxicity tests were performed with a water sample upstream and downstream the industry using the microcrustaceans Daphnia magna, Ceriodaphnia dubia and Ceriodaphnia silvestrii as test organisms, as well as physical and chemical analysis of water. Results showed that physical and chemical parameters did not change during the sampling period, except for the dissolved oxygen. No toxicity was observed for D. magna and reproduction of C. dubia and C. silvestrii in both sampling points. Thus, the industry was not negatively impacting the quality of this water body.

A cultura do tomate é frequentemente afetada por pragas, doenças e estresses abióticos, resultando em menor produtividade e perda de qualidade dos frutos. O uso intensivo de pesticidas em tomates sem utilização das boas práticas agrícolas tem causado grande preocupação quanto à provável contaminação do produto final. O método QuEChERS foi utilizado para a determinação de seis pesticidas (buprofezina, carbofurano, α-endosulfan, β-endosulfan, sulfato de endosulfan e monocrotofós) em amostras de tomate coletadas em supermercados. O método envolveu a extração líquido-líquido com acetonitrila, adição de MgSO4 e NaCl seguida de extração em fase sólida dispersiva com PSA (amina primária secundária) e as análises foram realizadas com cromatografia gasosa/espectrometria de massa ion trap. O estudo de recuperação para os pesticidas variou de 71 a 111% e o desvio padrão relativo foi inferior a 15%. Não foram detectados resíduos de pesticidas (> LOD) nas trinta e três amostras de tomate analisadas.

Tomato crop is frequently damaged by diseases, pests and abiotic stresses, resulting in lower yielding and loss of fruit quality. The intensive use of pesticides in tomatoes without observation of good agriculture practices and regulations has caused great concern with a probable final product contamination. The QuEChERS method of sample preparation was used for the determination of six pesticides (buprofezin, carbofuran, endosulfan-α, endosulfan-β, endosulfan sulfate and monocrotophos) in thirty three tomato samples collected from local market retailers. The method involved extraction with acetonitrile, liquid-liquid partition with addition of MgSO4 and NaCl followed by dispersive solid phase extraction using primary secondary amine sorbent and the analyses were carried out with a gas chromatography/mass spectrometry equipment by ion trap. Recovery studies for different pesticides ranged from 71 to 111% and the relative standard deviation (RSD) was below 15%. No pesticide residue was detected (> LOD) among the thirty three tomato samples analysed.

A calagem é uma prática de manejo da fertilidade muito utilizada e considerada essencial em solos tropicais. Essa prática, por influenciar as propriedades físicas, químicas e biológicas dos solos, pode também alterar o comportamento de moléculas orgânicas. Objetivou-se, neste estudo, avaliar o efeito da calagem na mineralização do herbicida glifosato em um Latossolo Vermelho (LE) e em um Neossolo Quartzarênico (RQ) e também na atividade microbiana dos mesmos solos. Os experimentos foram conduzidos em delineamento inteiramente casualizado em esquema fatorial 2 x 2, correspondendo a dois solos e a duas condições de manejo (com e sem calagem). Para o ensaio de mineralização, técnicas radiométricas foram utilizadas para avaliar a evolução do 14CO2 a intervalos de 7 dias, durante 70 dias. O estudo de atividade microbiana foi conduzido paralelamente ao experimento de mineralização, usando a metodologia de glicose radiomarcada (14C-glicose), a qual foi avaliada a intervalos de quatorze dias, durante 70 dias. Pelos resultados, foi possível verificar que nos dois solos estudados, a calagem aumentou significativamente a mineralização do 14C-glifosato e a atividade da microbiota.

Liming is a widely used soil fertility management practice and essential in tropical soils. This practice, by influencing physical, chemical and biological features of soils, may alter the behavior of organic molecules in soils. In this context, the objective of the present study was to evaluate the effect of liming on the mineralization of glyphosate in Red Latosol (LE) and Quartzarenic Neosol (RQ) soils and also on the microbial activity. The experiments were conducted in completely randomized design blocks in a 2 x 2 factorial scheme, corresponding to two soils and two management conditions (with and without liming). The radiometric technique was used to evaluate the evolution of 14CO2 at intervals of 7 days, during 70 days. The study of microbial activity was conducted using the methodology of radiolabelled glucose (14C-glucose), which was measured at intervals of fourteen days, during 70 days. Results show that the liming increased significantly the 14C-glyphosate mineralization and the microbial activity.

No Brasil, os produtos de manga fazem uso intenso do paclobutrazol como regulador de crescimento. No entanto, pouco se sabe sobre seu potencial de transporte em condições de solo e clima brasileiros. O presente estudo teve como objetivo avaliar a sorção e a mobilidade do paclobutrazol (PBZ), um fitorregulador de crescimento do grupo químico triazol, em um solo franco-arenoso da região submédia no vale do rio São Francisco, onde é intenso o cultivo de manga. O estudo de sorção foi realizado por meio de isotermas, em cinco concentrações (1,24; 2,48; 5,08; 10,22; e 20,52 mg L-1), utilizando o produto radioativo (14C-PBZ) como traçador. A dessorção foi avaliada após o descarte do sobrenadante e subseqüente adição de solução de CaCl2 0,01 mol L-1, etapa esta que foi repetida quatro vezes. Já a mobilidade do PBZ foi avaliada em colunas empacotadas com solo, com a simulação de 300 mm de chuva, uniformemente distribuída durante 72 h. O PBZ apresentou baixo potencial de sorção no solo estudado (Kf = 1,06 mg1-N L N kg-1; Kd (médio) = 0,83 L kg-1; e K OC (médio) = 165,7 L kg-1), o que correspondeu à sorção, em média, de 24,7 % da quantidade aplicada. No processo de dessorção, apenas 5,3 % do PBZ aplicado ficou retido às partículas do solo, e 19,4 % foi dessorvido à solução do solo. Portanto, em média, 75,3 % do PBZ aplicado não foi sorvido e 19,4 % foi dessorvido, totalizando 94,7 % do produto disponível na solução do solo. Apesar disso, apenas 0,83 % do PBZ aplicado foi lixiviado da coluna de solo, e 43,7 % da quantidade aplicada foi transportada para além dos primeiros 10 cm de profundidade do solo. Portanto, a mobilidade do PBZ foi menor do que aquela esperada, por se tratar de um solo com elevado teor de areia (77,5 %) e baixo teor de C orgânico (5 g dm-3) e em razão da grande quantidade de chuva simulada (300 mm). Mesmo assim, não se pode descartar, pelo menos totalmente, a possibilidade de que possa ocorrer lixiviação do PBZ, uma vez que ele mostrou mobilidade no perfil da coluna.

In Mango cultivation under Brazil conditions paclobutrazol (PBZ), a growth regulator, is very used. However it is not yet well known about the leaching potential of PBZ in these soil conditions. The objectives of this study were to evaluate sorption and mobility of paclobutrazol (PBZ), a growth regulator of the chemical group triazol, in a sandy loam soil found in the sub-mid region of the San Francisco River valley, where mango cultivation is intense. The sorption study was based on isotherms, at five different concentrations (1.24; 2.48; 5.08; 10.22; and 20.52 mg L-1), using the radioisotope (14C-PBZ) as tracer. Desorption was evaluated after discarding the supernatant and further addition of 0.01 mol L-1 CaCl2 solution, and repeating the entire process four times. The PBZ mobility was evaluated in packed soil columns, under an evenly distributed rainfall simulation of 300 mm for 72 h. The PBZ detected low sorption potential in the studied soil (Kf = 1.06 mg1-N L N kg-1; Kd (mean) = 0.83 L kg-1 and K OC (mean) = 165.7 L kg-1), corresponding to a mean of 24.7 % of the applied amount. After desorption, only 5.3 % of the applied PBZ was still sorbed to the soil particles, thus 19.4 % of the applied amount was desorbed to the soil solution. Therefore, 75.3 % of the applied PBZ remained in solution after sorption and 19.4 % was desorbed, totalizing an amount of 94.7 % of the compound available in the soil solution. However, only 0.83 % of the applied PBZ leached through the soil columns, but 43.7 % of the applied amount was transported below the upper 10 cm of the soil profile. PBZ mobility was therefore lower than expected, even when taking the high sand (77.5 %) and low organic C (5 g dm-3) soil contents into consideration and that rainfall simulation was rather intense (300 mm). Nevertheless, the possibility of leaching could not be ruled out in view of the PBZ mobility in the soil profile.