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1.
Environ Sci Pollut Res Int ; 26(21): 21274-21294, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31124062

RESUMO

Rice cultivation requires a large use of pesticides and nutrients to control weed proliferation and improve production. The water quality of four neighboring rice fields located in the Lomellina area (Italian Padana plain) was monitored in this study along with the cultivation period (before, during, and after the period of planting), for two successive agricultural seasons (2015 and 2016). Two paddy fields were traditionally cultivated with wet-seeding and the other fields with dry-seeding. Eighteen sampling points were considered: eight points for surface water, two points for underground water, and eight points for porous cups with two different depths. In order to evaluate the goodness of the paddy field system to maintain unchanged the quality of the inflow with respect to the outflow water, three of the most used herbicides in Italian rice cultivation (imazamox, oxadiazon, and profoxydim) and other physical-chemical parameters were determined, namely biological oxygen demand after 5 days; chemical oxygen demand; total suspended solids; anionic surfactants; total hardness; total amount of phosphorus, nitrogen, and potassium; and heavy metal concentrations. In general, all the collected data confirmed that paddy fields did not contribute to worsen the environmental pollution. The different flooding techniques adopted in the fields did not highlight significant differences in concentrations of pesticides or metals. The pesticides reached their maximum concentration (of the magnitude order of few ng mL-1) on the day after the administration and on the day after the application in the adjacent field. A slight reduction of total As in grain was obtained adopting a dry period from steam elongation up to booting. From the collected data, it was possible to identify a general water flow direction in the paddy fields from north-west to south-east: this prevailing flow direction was useful to understand not only the diffusion of the pesticides and their degradation products in the fields but also that of the nutrients. Concerning nutrients, it was important not to activate a recirculation of the water in the field during the first 10 days from the administration, in order to avoid loss of nitrogen in the water vents or for percolation. Moreover, the monitoring of potassium concentration allowed to avoid the use of unnecessary potassic fertilization when there was already a high amount of this element in the paddy field derived from irrigation. However, all the investigated water quality parameters were under the limits fixed by the European regulation. In addition, the presence of seven unexpected compounds was identified by the nontarget approach in both campaigns in samples collected in the early summer period. Four of these emerging contaminants were identified as N,N-diethyl-meta-toluamide, tricyclazole, amidosulfuron, and one of the imazamox photodegradation products. Although the obtained low concentrations of oxadiazion, tricyclazole, and arsenic, in particular, justified a preexisting contamination of the water inflow or of the investigated paddy area, the obtained results supported the good quality of the paddy water outflow, confirming the rational use of the water resource and the correct use of agronomic practices.


Assuntos
Agricultura , Monitoramento Ambiental , Oryza/crescimento & desenvolvimento , Poluentes Químicos da Água/análise , Arsênio , Fazendas , Água Subterrânea , Metais Pesados/análise , Nitrogênio/análise , Oryza/química , Praguicidas/análise , Fósforo/análise , Água/química , Qualidade da Água
2.
Anal Chim Acta ; 1042: 141-154, 2018 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-30428981

RESUMO

The paper deals with the development of an online UHPLC-MS/MS method for the identification and determination of 25 Endocrine Disrupting Chemicals (EDCs) belonging to different chemical classes (perfluorochemicals, bisphenols, alkylphenols, phthalates, and parabens). The study regards the possible EDC migration from different medical devices of diverse materials used in the routine hospitals for blood sampling or for the parenteral nutrition therapies. In order to evaluate the release of EDCs, the equipment used for blood sampling (syringes, butterfly, cannula-needle, microcapillary tube) was put in contact with a physiological solution at a prefixed time. As regards the migration tests carried out on the medical devices used in the parenteral nutrition therapy (infusion tubes, venous catheters), the catheters were undergone to internal contact with parenteral solution and external contact with physiological one, whereas the infusion tubes were subjected only to internal migration test with parenteral solution. The results demonstrated the released of some ECDs (such as parabens at the concentration of few pg mL-1, diethylphthalate and dibutylphthlate at ng mL-1, level), when using physiological solution as the leaching agent. In addition, the presence of a PFOS structural isomer was found at 29.0 ng mL-1: this compound was released in part from the infusion tubes and mostly from the venous catheters, particularly from silicone ones. Using a more lipophilic solution, such as parenteral preparations, a greater amount of EDCs was released, among which also the diethylhexylphthalate that was quantified in all the investigated devices (without highlighting particular trends or migration from PVC devices), but its concentration remained always lower than imposed maximum threshold limit on medical device of 0.1% w/w. The releases from the infusion tubes of the same materials (polyethylene) from different manufacturers are very comparable, whereas the catheter of silicone releases greater amount of EDCs than that of polyurethane.


Assuntos
Disruptores Endócrinos/análise , Equipamentos e Provisões , Extração em Fase Sólida , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem
3.
Planta Med ; 82(14): 1295-301, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27124243

RESUMO

Pterocarpus marsupium is a well-known plant due to its healing properties, in particular, the use of its aqueous extract is able to reduce blood sugar levels and blood triglyceride concentrations. Although this plant has already been widely studied, a complete characterization of its aqueous extract has not been reported. The present study deals with the characterization of the aqueous extract of P. marsupium in order to obtain a full fingerprint of the volatile and nonvolatile constituents. The volatile constituents were identified by CG-MS, whereas the nonvolatile fraction was characterized by UHPLC-MS/MS using a nontarget approach. Several compounds were identified, in particular, polyphenolic species belonging to the class of proanthocyanidins. Cytotoxicity tests were carried out on four different cancer cell lines and three different non-tumoral cell lines. Preliminary results indicate a selective cytotoxicity of the aqueous extract towards the cancer cells. The potential cytotoxicity due to the presence of metals in the aqueous extract was ruled out by testing an aqueous mixture of the metals at the same concentration found in the P. marsupium extract.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Extratos Vegetais/farmacologia , Pterocarpus/química , Animais , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Camundongos , Extratos Vegetais/química , Volatilização
4.
J Sep Sci ; 38(18): 3130-3136, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26136320

RESUMO

A new ultra high performance liquid chromatography coupled with tandem mass spectrometry method for a fast and sensitive determination of eight polyphenols (hydroxytyrosol, catechin, epicatechin, epigallocatechin gallate, oleuropein, quercetin, rutin, tyrosol) and panthotenic acid in extra-virgin olive oil was developed. The method does not require long sample pre-treatment and presents the lowest limit of detection and limit of quantitation values present in literature. Inter- and intra-day variability, linear dynamic range of the calibration curve, recovery and matrix effect were also determined and investigated. The method was applied to several oil samples of different type and origin. Given its accuracy, precision and rapidity, the method is characterized by an interestingly high throughput, reliability, and sensitivity.

5.
Anal Bioanal Chem ; 407(16): 4649-59, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25939426

RESUMO

This article deals with the photodegradation of sulforhodamine B, a dye widely used in nonpermanent tattoos. Degradation evidence was obtained from both aqueous and sweat-simulating solutions of the dye after 9 days of Solarbox irradiation. The identification of the degradation products was achieved using a nontarget approach. For this purpose, a micro liquid chromatography method coupled with tandem high-resolution mass spectrometry was developed. In addition, the chemical structures of five degradation products and two dye impurities were elucidated. The degradation products were the same for both types of solution, whereas the degradation rate of the dye in sweat-simulating solution was slightly faster than that in aqueous solution. The method was also applied to samples of tattooed pigskin subjected to irradiation, in order to better simulate the irradiation effects on the dye used on the skin. None of the degradation products found in the sulforhodamine B solutions were identified in the degraded tattooed pigskin samples, but a new signal at m/z 637.3051 (positive ionization) was found, and the structure of the corresponding molecule was elucidated. The mutagenicity of the photodegradation products was evaluated using a quantitative structure-activity relationship approach, which gave negative results for all the structures elucidated. Graphical Abstract Comparison between tattoed pigskin before and after photodegration process. Strategies for the identification of sulforhodamine B degradation products.


Assuntos
Cromatografia Líquida/métodos , Rodaminas/química , Espectrometria de Massas em Tandem/métodos , Tatuagem , Processos Fotoquímicos
6.
Environ Sci Pollut Res Int ; 22(11): 8288-95, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25529495

RESUMO

This paper reports the study of the photodegradation reactions that tricyclazole can naturally undergo, under the action of sunlight, in aqueous solutions of standard tricyclazole and of the commercial BEAM(TM) formulation. The analyses are carried out by ultra-high performance liquid chromatography technique coupled with high-resolution tandem mass spectrometry. Analysis of both tricyclazole and BEAM(TM) water solutions undergone to hydrolysis does not evidence new chromatographic peaks with respect to the not treated solutions. On the contrary, analysis of the same samples subjected to sunlight irradiation shows a decreased intensity of tricyclazole signal and the presence of new chromatographic peaks. Two photodegradation products of tricyclazole have been identified, one of which has been also quantified, being the commercial standard available. The pattern is similar for the solutions of the standard fungicide and of the BEAM(TM) formulation. The results obtained from eco-toxicological tests show that toxicity of tricyclazole standard solutions is greater than that of the irradiated ones, whereas toxicity levels of all the BEAM(TM) solutions investigated (non-irradiated, irradiated, and hydrolyzed) are comparable and lower than those shown by tricyclazole standard solutions. Experiments performed in paddy water solution show that there is no difference in the degradation products formed.


Assuntos
Fotólise , Luz Solar , Tiazóis/química , Água/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Fungicidas Industriais/química , Hidrólise , Espectrometria de Massas , Soluções , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/análise
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