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1.
Anal Methods ; 14(29): 2857-2865, 2022 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-35833565

RESUMEN

This work presents the optimization and validation of a method to quantify organochlorine pesticides in tobacco samples from smuggled cigarettes using ultrasound application and low-temperature extraction. The combined approach was validated for 20 organochlorine pesticides, achieving recoveries between 73% and 116%, and a relative standard deviation of less than 20%. The method minimized the matrix effect in 65% of the organochlorine pesticides. The limits of detection and quantification varied from 2 to 60 ng g-1 and 120 to 190 ng g-1, respectively. The method was applied to the analysis of 18 brands of smuggled cigarettes. The organochlorine pesticides found in the samples were cis-chlordane (89%), p,p'-dichlorodiphenyldichloroethylene (DDD) and methoxychlor (78%), endosulfan sulfate (67%), heptachlor epoxide, and endosulfan II (61%). The concentrations of the organochlorine pesticides in this study were higher than those in a similar survey on cigarettes marketed in China. The ultrasound application and low-temperature extraction may be an efficient alternative to analyzing tobacco samples since it uses only one extraction solvent, requires low-cost equipment, does not require an additional clean-up step, reduces the environmental impact through minimal waste generation, and can detect low analyte concentrations.


Asunto(s)
Hidrocarburos Clorados , Plaguicidas , Productos de Tabaco , Diclorodifenil Dicloroetileno/análisis , Hidrocarburos Clorados/análisis , Plaguicidas/análisis , Temperatura , Nicotiana
2.
Sci Total Environ ; 699: 134377, 2020 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-31671305

RESUMEN

This study evaluated the chemical and microbiological properties of the compost obtained from the tobacco of smuggled cigarettes (SCT) and industrial sewage sludge (ISS). The composting was carried out in three reactors from different combinations of residues. The compost was analyzed to verify the percentage of nicotine removal, heavy metals, nutrient content and the inactivation of pathogenic microorganisms. The concentration of heavy metals: Ni, Cd, Cr, Pb, Cu, Zn, Fe and Mn in the composts obtained from the three reactors was below the values set for their use in soils. The NPK content ranged between 8.31% and 12.43%, indicating that the compost produced can add nutritional benefits to the plants. The nicotine removal, 72.6% (R1), 96.4% (R2) and 99.6% (R3) indicated efficiency of the composting process in reactors in the degradation of this substance. The results of pathogenic microorganism analysis showed that the three composts obtained from reactors R1, R2 and R3 met the sanitation standards for agricultural use according to the normative of maximum limits of contaminants allowed in organic compounds. These results show that the treatment of SCT and ISS by the process of composting in reactors may be an ecologically viable alternative.


Asunto(s)
Compostaje , Nicotiana , Contaminantes del Suelo/análisis , Productos de Tabaco , Metales Pesados/análisis , Nicotina/análisis , Nutrientes , Compuestos Orgánicos
3.
Aquat Toxicol ; 205: 123-129, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30384193

RESUMEN

The present work aimed to assess the genotoxic effects of intraperitoneally injected copper in males of O. niloticus, and to investigate its association with eventual changes in the quality of the gametes and in the generation of offspring abnormalities. Thus, to evaluate DNA damage, the alkaline comet assay was performed in sperm and blood; sperm parameters were analyzed to determine the quality of the gametes, and the incidence of morphological abnormalities of larvae, originated from eggs fertilized by males exposed to copper, was used as a measure of reproductive impairment. Male fish were exposed to three doses (1 mg/kg, 2 mg/kg, 4 mg/kg) of copper sulfate via intraperitoneal injection and observed after 96 h of exposure. We found that the quality of gametes was not affected by copper, as indicated by the lack of differences in sperm parameters between the exposed and the control groups. Nonetheless, copper induced an increase in sperm DNA damage at all tested doses. Taking into consideration the total number of abnormalities, larvae presented a higher proportion of morphological abnormalities at all the tested doses. Considering the morphological abnormalities separately, the 2 mg/kg and 4 mg/kg groups presented significantly higher frequencies of arrested development and spinal abnormalities than the control group. This work suggests that intraperitoneally injected copper is an inductor of DNA breakage in germ cells of O. niloticus males. Copper induces the formation of larval morphological abnormalities, causing reproductive impairment to this species. The fact that copper did not induce alterations on sperm parameters indicates that the parental genotoxic effects are inheritable to the offspring.


Asunto(s)
Cíclidos/fisiología , Cobre/toxicidad , Daño del ADN/efectos de los fármacos , Animales , Cíclidos/genética , Ensayo Cometa , Inyecciones Intraperitoneales , Masculino , Pruebas de Mutagenicidad , Reproducción/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad
4.
Waste Manag ; 79: 537-544, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30343785

RESUMEN

The maturity of smuggled cigarette tobacco (SCT) and industrial sewage sludge (ISS) compost during composting in reactors was evaluated through physicochemical, phytotoxic and spectroscopic parameters. The temperatures reached peaks above 52 °C in the three reactors and were enough to achieve the stability of the compounds. The electric conductivity was in the optimal interval for farming uses and the pH alkaline band was favorable to produce inorganic nitrogen. The reduction in the C∕N ratio and the increase in cation exchange capacity (CEC) indicated an increase in the compost humification. After 120 days, the seed germination index (SGI) reached 95 % in reactor 3. In the three treatments, the reduction in E2/E6 and E4/E6 ratios (UV/Vis), the increase in humification indices, obtained through FTIR and the aromatic carbon resonance (13C NMR) indicated a high degree of aromaticity. The composting process in reactors was efficient to degrade different proportions of SCT and ISS, resulting in mature composts.


Asunto(s)
Compostaje , Productos de Tabaco , Aguas del Alcantarillado , Suelo , Nicotiana
5.
Ecotoxicol Environ Saf ; 155: 26-36, 2018 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-29499429

RESUMEN

The circadian clock is a key cellular timing system that coordinates physiology and behavior. Light is a key regulator of the clock mechanism via its activation of Per and Cry clock gene expression. Evidence points to a key role of reactive oxygen species (ROS) in resetting this process. In this context, the aim of the present study was to explore copper as a ROS generator, using an innovative approach investigating its effects on circadian timing. Liver and brain from Danio rerio specimens exposed to 0, 5, 25 and 45 µg/L copper concentrations were obtained. Daily oscillations of superoxide dismutase (SOD) and catalase (CAT) enzymatic activity and their correlations both with clock genes (per1, per2, and cry1a) and with organism energy cost were determined. CAT expression correlates with per2 and cry1a and, thus, provides data to support the hypothesis of hydrogen peroxide production by a phototransducing flavin-containing oxidase. Higher SOD activity is correlated with higher intracellular ATP levels. Copper disturbed the daily oscillation of antioxidant enzymes and clock genes, with disturbed per1 rhythmicity in both the brain and liver, while cry1a rhythmicity was abolished in the liver at 25 µg/L copper. Coordination between the SOD and the CAT enzymes was lost when copper concentrations exceeded the limits established by international laws. These results indicate that organism synchronization with the environment may be impaired due to acute copper exposure.


Asunto(s)
Relojes Circadianos/efectos de los fármacos , Cobre/toxicidad , Proteínas Circadianas Period/metabolismo , Proteínas de Pez Cebra/metabolismo , Animales , Catalasa/metabolismo , Criptocromos/genética , Criptocromos/metabolismo , Proteínas del Ojo/genética , Proteínas del Ojo/metabolismo , Femenino , Expresión Génica/efectos de los fármacos , Masculino , Proteínas Circadianas Period/genética , Superóxido Dismutasa/metabolismo , Pez Cebra/genética , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética
6.
Waste Manag ; 71: 115-121, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29102359

RESUMEN

This paper presents a study on the degradation of smuggled cigarette tobacco combined with domestic organic waste and sawdust or wood chips, using facultative reactor. Four reactors with different amounts of residue were assembled. For the study of the quality of the compost obtained, physicochemical, phytotoxicity and microbiological analyses were carried out. The mixture with wood chips presented the best temperature conditions and pH variation optimizing the degradation. The final germination index (GI) values of all treatments were above the recommended GI value (50%) and the final C/N ratio between 8 and 13 indicated a mature compost. The concentration of metals under study was below the limit allowed for the commercialization. The composting carried out in all facultative reactors provided ideal conditions for the total sterilization of the final compost. Therefore, the treatment of smuggled cigarettes through facultative reactors was efficient to produce stable and mature compost.


Asunto(s)
Compostaje , Productos de Tabaco , Estiércol , Suelo , Madera
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