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1.
Nutr Cancer ; 67(7): 1063-74, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26368676

RESUMO

It has been extensively investigated that the chewing of smokeless tobacco (SLT) products may enhance the inflammation of the oral cavity. The aim of the present study is to evaluate the relationship between nickel (Ni) exposure via different SLT products with oral cancer (different sites) incidence in the population of Sindh, Pakistan. The different brands of SLT products (mainpuri, gutkha, and moist snuff) commonly consumed by the studied population were analyzed for Ni contents. The biological samples of oral cancer patients and noncancerous control subjects of both genders, who have or have not consumed SLT products, were collected. The concentration of Ni in biological samples and SLT products were measured by electrothermal atomic absorption spectrophotometer after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked by using certified reference materials. The results of this study showed that the Ni level was significantly higher in scalp hair and blood samples of oral cancer patients compared to controls (P < 0.01). The study suggested that exposure of Ni as a result of chewing different SLT products may be synergistic with risk factors associated with oral cancer.


Assuntos
Neoplasias Bucais/epidemiologia , Níquel/análise , Níquel/toxicidade , Tabaco sem Fumaça/análise , Adulto , Estudos de Casos e Controles , Feminino , Cabelo/química , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/induzido quimicamente , Neoplasias Bucais/metabolismo , Níquel/sangue , Paquistão/epidemiologia , Fatores Socioeconômicos , Espectrofotometria Atômica , Tabaco sem Fumaça/toxicidade
2.
Environ Sci Pollut Res Int ; 22(23): 19251-63, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26254562

RESUMO

In present study, the ground water at different aquifers was evaluated for physicochemical parameters, iron, total arsenic, total inorganic arsenic and arsenic species (arsenite and arsenate). The samples of groundwater were collected at different depths, first aquifer (AQ1) 50-60 m, second aquifer (AQ2) 100-120 m, and third aquifer (AQ3) 200-250 m of Thar coalfield, Pakistan. Total inorganic arsenic was determined by solid phase extraction using titanium dioxide as an adsorbent. The arsenite was determined by cloud point extraction using ammonium pyrrolidinedithiocarbamate as a chelating reagent, and resulted complex was extracted by Triton X-114. The resulted data of groundwater were reported in terms of basic statistical parameters, principal component, and cluster analysis. The resulted data indicated that physicochemical parameters of groundwater of different aquifers were exceeded the World Health Organization provisional guideline for drinking water except pH and SO4(2-). The positive correlation was observed between arsenic species and physicochemical parameters of groundwater except F(-) and K(+), which might be caused by geochemical minerals. Results of cluster analysis indicated that groundwater samples of AQ1 was highly contaminated with arsenic species as compared to AQ2 and AQ3 (p > 0.05).


Assuntos
Arsênio/análise , Água Subterrânea/análise , Poluentes Químicos da Água/análise , Adsorção , Água Potável/análise , Ferro/análise , Octoxinol , Paquistão , Polietilenoglicóis , Extração em Fase Sólida , Titânio/química , Qualidade da Água
3.
Biol Trace Elem Res ; 168(2): 287-95, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25975948

RESUMO

It has been extensively reported that chewing of smokeless tobacco (SLT) can lead to cancers of oral cavity. In present study, the relationship between arsenic (As) exposure via chewing/inhaling different SLT products in oral cancer patients have or/not consumed SLT products was studied. The As in different types of SLT products (gutkha, mainpuri, and snuff) and biological (scalp hair and blood) samples of different types of oral cancer patients and controls were analyzed. Both controls and oral cancer patients have same age group (ranged 30-60 years), socio-economic status, localities, and dietary habits. The concentrations of As in SLT products and biological samples were measured by electrothermal atomic absorption spectrophotometer after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked by certified reference materials. The resulted data of present study indicates that the concentration of As was significantly higher in scalp hair and blood samples of oral cancer patients than those of controls (p<0.001). It was also observed that the values of As were two- to threefolds higher in biological samples of controls subjects, consuming SLT products as compared to those have none of these habits (p>0.01). The intake of As via consuming different SLT may have synergistic effects, in addition to other risk factors associated with oral cancer.


Assuntos
Arsênio/análise , Neoplasias Bucais/sangue , Neoplasias Bucais/metabolismo , Nicotiana/química , Tabaco sem Fumaça/análise , Adulto , Estudos de Casos e Controles , Feminino , Cabelo/química , Humanos , Concentração de Íons de Hidrogênio , Masculino , Micro-Ondas , Pessoa de Meia-Idade , Paquistão , Fosforilação , Padrões de Referência , Reprodutibilidade dos Testes , Couro Cabeludo/efeitos dos fármacos , Fumar/efeitos adversos , Classe Social , Espectrofotometria Atômica
4.
Environ Sci Pollut Res Int ; 22(16): 12396-406, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25903188

RESUMO

Several studies have reported that the chewing habit of smokeless tobacco (SLT) has been associated with oral cancer. The aim of the present study was to evaluate the trace levels of lead (Pb) in biological samples (blood, scalp hair) of oral cancer patients and referents of the same age group (range 30-60 years). As the concentrations of Pb are very low in biological samples, so a simple and efficient ionic liquid-based microextraction in a single syringe system has been developed, as a prior step to determination by flame atomic absorption spectrometry. In this procedure, the hydrophobic chelates of Pb with ammonium pyrrolidinedithiocarbamate (APDC) were extracted into fine droplets of 1-butyl-3-methylimidazolium hexafluorophosphate [C4MIM][PF6] within a syringe while using Triton X-114 as a dispersant. Factors influencing the microextraction efficiency and determination, such as pH of the sample, volume of [C4MIM][PF6] and Triton X-114, ligand concentration, and incubation time, were studied. To validate the proposed method, certified reference materials were analyzed and the results of Pb(2+) were in good agreement with certified values. At optimum experimental values of significant variables, detection limit and enhancement factor were found to be 0.412 µg/L and 80, respectively. The coexisting ions showed no obvious negative outcome on Pb preconcentration. The proposed method was applied satisfactorily for the preconcentration of Pb(2+) in acid-digested SLT and biological samples of the study population. It was observed that oral cancer patients who consumed different SLT products have 2-3-fold higher levels of Pb in scalp hair and blood samples as compared to healthy referents (p < 0.001). While 31.4-50.8% higher levels of Pb were observed in referents chewing different SLT products as compared to nonconsumers (p < 0.01).


Assuntos
Cabelo/química , Líquidos Iônicos/química , Chumbo/sangue , Chumbo/isolamento & purificação , Microextração em Fase Líquida/métodos , Neoplasias Bucais/sangue , Tabaco sem Fumaça/efeitos adversos , Adulto , Quelantes/química , Feminino , Humanos , Imidazóis/química , Chumbo/química , Ligantes , Limite de Detecção , Microextração em Fase Líquida/instrumentação , Masculino , Pessoa de Meia-Idade , Pirrolidinas/química , Análise de Regressão , Espectrofotometria Atômica , Seringas , Tiocarbamatos/química
5.
Environ Sci Pollut Res Int ; 22(1): 350-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25074830

RESUMO

The combined exposure of arsenic (As) and cadmium (Cd) causes more pronounced renal toxicity. The study aimed to evaluate the level of As and Cd in biological samples (blood and urine) of adults males, age ranged (30-50 years) exposed referent (ER) and exposed kidney patients (EKP), consumed contaminated drinking water of lake and smoking local cigarettes manufactured by tobacco plants grown on agricultural soil, irrigated with contaminated lake water. For comparative purpose age matched nonexoposed referent (NR) and nonexposed kidney patient (NKP), consumed municipal treaded water and smoking branded cigarette were also selected. The As and Cd levels in drinking water, biological samples, tobacco of branded and nonbranded cigarettes were analyzed using electrothermal atomic absorption spectrometry. The As and Cd concentrations in lake water were higher than the permissible limit recommended by the World Health Organization for drinking water. The As and Cd levels in local cigarette tobacco were found to be 3- to 4-folds higher than branded cigarettes. The biochemical parameters especially urinary N-acetyl-ß-glucosaminidase (NAG) of ER, EKP, ER, and EKP subjects were studied as a biomarkers of renal dysfunction. The NAG values were found to be higher in EKP as compared to NKP (p < 0.01). The linear regressions showed higher correlations between As and Cd concentrations in water versus blood and urine samples of EKP (r = 0.71-0.78 and 0.68-0.72), as compared to NKP (p < 0.05).


Assuntos
Arsênio/toxicidade , Cádmio/toxicidade , Exposição Ambiental , Nefropatias/induzido quimicamente , Fumar/efeitos adversos , Poluentes Químicos da Água/toxicidade , Adulto , Arsênio/análise , Arsênio/sangue , Biomarcadores/sangue , Cádmio/análise , Cádmio/sangue , Estudos de Casos e Controles , Água Potável/análise , Água Potável/química , Humanos , Rim/química , Lagos/análise , Lagos/química , Masculino , Pessoa de Meia-Idade , Medição de Risco , Nicotiana/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/sangue
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 137: 877-85, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25280335

RESUMO

A green and sensitive temperature controlled dispersive liquid-liquid microextraction (TIL-DLLME) methodology based on the application of ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate, [C4mim][PF6], as an extractant solvent was proposed for the preconcentration of trace levels of aluminium (Al(3+)) in scalp hair samples of Alzheimer's (AD) patients, prior to analyzing by flame atomic absorption spectrometry (FAAS). The Al(3+) was complexed with 8-hydrooxyquinoline (oxine) (L1) and 3,5,7,2'-4' pentahydroxy flavone (morin) (L2) separately and then extracted by IL at temperature (50±2.0°C). Some effective factors that influence the TIL-DLLME efficiency such as pH, ligands concentrations, volume of IL, ionic strength, and incubation time were investigated and optimized by multivariate analysis. In the optimum experimental conditions, the limit of detection (3s) and enhancement factor were 0.56 µg L(-1), 0.64 µg L(-1) and 85, 73 for both ligands, respectively. The relative standard deviation (RSD) for six replicate determinations of 100 µg L(-1) Al(3+) complexed with oxine and morin were found to be 3.88% and 4.74%, respectively. The developed method was validated by the analysis of certified reference material of human hair (NCSZC81002).and applied satisfactorily to the determination of Al(3+) in acid digested scalp hair samples of AD patients and healthy controls. The resulted data shows significant higher level in scalp hair samples of AD male patients with related to referents of same age and socioeconomic status.


Assuntos
Alumínio/análise , Doença de Alzheimer/diagnóstico , Cabelo/química , Microextração em Fase Líquida , Ácidos/química , Idoso , Alumínio/química , Calibragem , Estudos de Casos e Controles , Transtornos Cognitivos/diagnóstico , Flavonoides/química , Humanos , Ligantes , Masculino , Micro-Ondas , Pessoa de Meia-Idade , Análise Multivariada , Oxiquinolina/química , Reprodutibilidade dos Testes , Couro Cabeludo , Espectrofotometria Atômica
7.
Biol Trace Elem Res ; 164(2): 178-84, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25537077

RESUMO

The present study was aimed to evaluate the cadmium (Cd) and lead (Pb) levels in the scalp hair samples of adolescent boys age ranged 12-15 years, chewing different smokeless tobacco (SLT) products. For comparative purpose, boys of the same age group who did not consume any SLT products were selected as referents. The concentrations of Cd and Pb in SLT products and the scalp hair samples were measured by electrothermal atomic absorption spectrophotometer (ETAAS) after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked by certified reference materials (CRMs). The difference between experimental and certified values of both elements was not significant (p > 0.05). The resulted data indicated that the adolescent boys who consumed different SLT products have two- to threefold higher levels of Cd and Pb in the scalp hair samples as compared to the referent boys (p < 0.01). The adolescent chewing different SLT products have 82.2-110 and 60.6-94.5% higher levels of Cd and Pb, respectively, in their scalp hair as related to the referents.


Assuntos
Cádmio/análise , Cabelo/química , Chumbo/análise , Tabaco sem Fumaça/análise , Adolescente , Criança , Humanos , Masculino , Valores de Referência , Reprodutibilidade dos Testes , Couro Cabeludo , Espectrofotometria Atômica/métodos , Tabaco sem Fumaça/efeitos adversos , Tabaco sem Fumaça/classificação
8.
Chemosphere ; 100: 182-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24342361

RESUMO

The aim of present study was to simultaneously estimate the arsenic (As) and fluoride (F(-)) concentrations in irrigated surface water, soil and grain crops of Nagarparkar, Pakistan during 2010-2012. The As and F(-) were analyzed by hydride generation atomic absorption spectrometer and ion selective electrode, respectively. Total arsenic (As(T)) and F(-) in irrigated surface water samples were found in the range of 360-683 µg L(-1) and 18.5-35.4 mg L(-1), respectively. While As(T) and F(-) concentrations in agriculture soil samples were observed in the range of 110-266 and 125-566 mg kg(-1), respectively. The water extractable As and F(-) were found 3-4% of total concentration of these in soils. The As(T) concentration was higher in kidney been (KB) as compared to pearl millet (PM) and green gram (GG), whereas GG had higher F(-) levels as compared to other two grain crops (p<0.05). The KB samples grown in nine sites shows BCF of As in the range of 0.018-0.038. The GG has higher BCF of F(-) as compared to KB and PM (p<0.05) grown in all sites. The exposure dose and risk factor of As and F(-) were obtained by estimated daily intake (EDI) and hazardous index (HI). It was found that all understudy age groups were at the severe risk of arsenicosis and fluorosis, but the severity is higher in younger age group (7-15 years) as compared to elder groups (p<0.05).


Assuntos
Arsênio/análise , Grão Comestível/química , Exposição Ambiental/análise , Poluentes Ambientais/análise , Fluoretos/análise , Água/química , Adolescente , Adulto , Criança , Análise por Conglomerados , Coleta de Dados , Ingestão de Líquidos , Humanos , Pessoa de Meia-Idade , Paquistão , Solo/química , Adulto Jovem
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