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1.
Environ Res ; 201: 111588, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34175289

RESUMO

In this study, magnetic sporopollenin supported cyanocalixarene (MSP-CyCalix) nanocomposite was synthesized and introduced as an adsorbent material for the removal of pesticides from aqueous media. MSP-CyCalix was characterized by different analytical techniques FTIR, SEM, EDX, BET, VSMand TEM. Chlorpyrifos and hexaconazole pesticides were chosen as model analytes solutions for testing the adsorption efficiency of MSP-CyCalix adsorbent. The adsorption results showed that the incorporated cyano functional groups significantly increased the chemical reactivity and adsorption capacity for pesticides. To obtain the highest possible performance, experimental parameters such as pH, salt, dosage and time were optimized. Adsorption kinetics and isotherms models showed that pesticide adsorption process was well fitted with the pseudo-second-order and Langmuir models with a maximum adsorption capacity of 13.88 mg g-1 and 12.34 mg g-1 and a removal efficiency of >90% for both pesticides. Lastly, MSP-CyCalix maintained a removal efficiency of >80% for ten cycles and 60% after the eleventh cycles of usage. The results proved that MSP-CyCalix nanocomposite can be used as an efficient adsorbent for the removal of pesticide residues from water.


Assuntos
Praguicidas , Biopolímeros , Carotenoides , Cinética , Fenômenos Magnéticos , Água
2.
Biol Trace Elem Res ; 175(2): 312-321, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27422637

RESUMO

The pervasive smokeless tobacco (SLT) consumption and diseases related to its use is a hot topic for the public discussion. In this study, concentrations of chromium (Cr) were measured in different SLT products [snuff (dry and moist), mainpuri, and gutkha] offered and used in Pakistan. The current study was also designed to assess the Cr levels in the biological (scalp hair and blood) samples of male and female subjects, age ranged from 25 to 60 years, chewing different SLT products. For comparative purpose, the healthy persons of the same age group, who did not consume any SLT products, were selected as referents. The concentrations of Cr 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 (CRMs). The resulted data indicated that the adult persons, who consumed different SLT products, have 2-3 fold higher levels of Cr in biological samples as compared to referent subjects (p < 0.01). The persons, who chew/sniff different SLT products, have 50-80 and 42-82 % higher levels of Cr in their scalp hair and blood samples as related to referents. The daily intake of Cr is lower as compared to the recommended value of 50-200 µg/day. It was expected that 10 g consumption of various kinds of SLT products (snuff, mainpuri, and gutkha) may subsidize 21.2-220, 17.7-122, and 18.4-273 % of the recommended daily intake of Cr, respectively.


Assuntos
Cromo/farmacocinética , Cromo/toxicidade , Cabelo/metabolismo , Tabaco sem Fumaça/efeitos adversos , Tabaco sem Fumaça/análise , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão
3.
Environ Sci Pollut Res Int ; 23(15): 15149-63, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27094273

RESUMO

In the present study, an indigenous biosorbent (leaves of Tecomella undulata) was used for the simultaneous removal of inorganic arsenic species (As(III) and As(V)) from the stored rainwater in Tharparkar, Pakistan. The Plackett-Burman experimental design was used as a multivariate strategy for the evaluation of the effects of six factors/variables on the biosorption of inorganic arsenic species, simultaneously. Central composite design (CCD) was used to found the optimum values of significant factors for the removal of As(III) and As(V). Initial concentrations of both inorganic As species, pH, biosorbent dose, and contact time were selected as independent factors in CCD, while the adsorption capacity (q e) was considered as a response function. The separation of inorganic As species in water samples before and after biosorption was carried out by cloud point and solid-phase extraction methods. Theoretical values of pH, concentration of analytes, biosorbent dose, and contact time were calculated by quadratic equation for 100 % biosorption of both inorganic As species in aqueous media. Experimental data were modeled by Langmuir and Freundlich isotherms. Thermodynamic and kinetic study indicated that the biosorption of As(III) and As(V) was followed by pseudo second order. It was concluded that the indigenous biosorbent material efficiently and simultaneously removed both As species in the range of 70.8 to 98.5 % of total contents in studied ground water samples. Graphical abstract Optimizing the significant varable by central 2(3) + star orthogonal composite design.


Assuntos
Arsênio/isolamento & purificação , Bignoniaceae/química , Folhas de Planta/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Paquistão , Extração em Fase Sólida , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Água/química
4.
Chemosphere ; 150: 320-328, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26921585

RESUMO

Simultaneous removal of fluoride (F(-)), inorganic arsenic species, As(III) and As(V), from aqueous samples has been performed using an economic indigenous biosorbent (Stem of Tecomella undulata). The inorganic As species in water samples before and after biosorption were determined by cloud point and solid phase extraction methods, while F(-) was determined by ion chromatography. Batch experiments were carried out to evaluate the equilibrium adsorption isotherm studies for As(III), As(V) and F(-) in aqueous solutions. Several parameters of biosorption were optimized such as pH, biomass dosage, analytes concentration, time and temperature. The surface of biosorbent was characterized by SEM and FTIR. The FTIR study indicated the presence of carbonyl and amine functional groups which may have important role in the sorption/removal of these ions. Thermodynamic and kinetic study indicated that the biosorption of As(III), As(V) and F(-) were spontaneous, exothermic and followed by pseudo-second-order. Meanwhile, the interference study revealed that there was no significant effect of co-existing ions for the removal of inorganic As species and F(-) from aqueous samples (p > 0.05). It was observed that the indigenous biosorbent material simultaneously adsorbed As(III) (108 µg g(-1)), As(V) (159 µg g(-1)) and F(-) (6.16 mg g(-1)) from water at optimized conditions. The proposed biosorbent was effectively regenerated and efficiently used for several experiments, to remove the As(III), As(V) and F(-) from real water sample collected from endemic area of Pakistan.


Assuntos
Arsênio/análise , Bignoniaceae/química , Fluoretos/análise , Caules de Planta/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Arsênio/química , Biomassa , Fluoretos/química , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Paquistão , Extração em Fase Sólida , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Termodinâmica , Água/química , Poluentes Químicos da Água/química
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 154: 157-163, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26520476

RESUMO

An innovative and simple miniaturized solid phase microextraction (M-SPME) method, was developed for preconcentration and determination of silver(I) in the fresh and waste water samples. For M-SPME, a micropipette tip packed with activated carbon cloth (ACC) as sorbent, in a syringe system. The size, morphology and elemental composition of ACC before and after adsorption of analyte have been characterized by scanning electron microscopy and energy dispersive spectroscopy. The sample solution treated with a complexing reagent, ammonium pyrrolidine dithiocarbamate (APDC), was drawn into the syringe filled with ACC and dispensed manually for 2 to 10 aspirating/dispensing cycle. Then the Ag- complex sorbed on the ACC in micropipette was quantitatively eluted by drawing and dispensing of different concentrations of acids for 2 to 5 aspirating/dispensing cycles. The extracted Ag ions with modifier were injected directly into the electrothermal atomic absorption spectrometry for analysis. The influence of different variables on the extraction efficiency, including the concentration of ligand, pH, sample volume, eluent type, concentration and volume was investigated. Validity and accuracy of the developed method was checked by the standard addition method. Reliability of the proposed methodology was checked by the relative standard deviation (%RSD), which was found to be <5%. Under the optimized experimental variables, the limits of detection (LOD) and enhancement factors (EF), were obtained to be 0.86 ng L(-1) and 120, respectively. The proposed method was successfully applied for the determination of trace levels of silver ions in fresh and waste water samples.


Assuntos
Complexos de Coordenação/química , Água Doce/análise , Pirrolidinas/química , Prata/análise , Microextração em Fase Sólida/instrumentação , Tiocarbamatos/química , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Desenho de Equipamento , Limite de Detecção , Reprodutibilidade dos Testes , Prata/isolamento & purificação , Espectrofotometria Atômica/instrumentação , Seringas , Poluentes Químicos da Água/isolamento & purificação
6.
Biol Trace Elem Res ; 172(1): 61-71, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26606915

RESUMO

Humans are exposed to arsenic (As) through air, drinking water, and food. The arsenic (As) hazardous quotient was calculated on the basis of its concentration in drinking water of different origin and scalp hair of male subjects (n = 313), residents of different exposed and non-exposed areas of Sindh, Pakistan. The total As was determined in water and scalp hair samples, while As species were determined in water samples by advance extraction methodologies. The total As concentrations in drinking water of less-exposed (LE) and high-exposed (HE) areas was found to be 2.63 to 4.46 and 52 to 235, fold higher than the permissible limit, respectively, than recommended by World Health Organization (2004) for drinking water. While the levels of As in drinking water of non-exposed (NE) areas was within the permissible limit. The resulted data indicated that the dominant species was As(+5) in groundwater samples. The levels of As in scalp hair samples of male subjects of two age groups (18-30 and 31-50 years), belonging to NE, LE, and HE areas, ranged from 0.26 to 0.69, 0.58 to 1.34, and 15.6 to 60.9 µg/g, respectively. A significant correlation between As levels in drinking water and scalp hair was observed in HE area (r = 0.86-0.90, p < 0.001) as compared to those subjects belonging to LE area. A toxicity risk assessment was calculated as hazard quotient (HQ), which indicates that the study subjects of HE area have significantly higher values of HQ than LE. The population of As exposed areas is at high risk of non-carcinogenic and carcinogenesis effects.


Assuntos
Intoxicação por Arsênico/epidemiologia , Arsênio/análise , Água Potável/análise , Cabelo/química , Adolescente , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Medição de Risco , Adulto Jovem
7.
Environ Sci Pollut Res Int ; 23(1): 878-86, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26347420

RESUMO

There is compelling evidence in support of interaction between calcium (Ca) and lead (Pb) in thyroid disorders. The aim of present study was to compare the level of Ca and Pb with thyroid hormones such as thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxin (FT4) in serum samples of hyperthyroid (HPRT) and hypothyroid (HPOT) patients of both genders. For comparative purpose, age-matched (25-50 years) subjects having no thyroid disorders were selected as referents/controls. The serum samples were acid-digested prior to analysis by atomic absorption spectrometry. The validity and accuracy of the methodology were checked by certified reference materials. The resulted data indicates that the mean values of Ca in serum samples of HPRT patients were significantly higher than those of referent subjects (p < 0.01), while reverse pattern was observed in the case of HPOT patients. The level of Pb was higher in the serum samples of both types of thyroid patients, but difference was significant in case of HPOT patients as compare to referent subjects (p < 0.01). A negative correlation was observed between serum Ca levels and TSH of HPRT patients (-r = 0.37-0.39, p < 0.01), while FT3 and FT4 have positive correlation (r = 0.49-0.52 and r = 0.46-0.47), p values <0.01. The Pb in serum had positive correlation with TSH (r = 0.48-0.51, p < 0.005), while negative correlation was observed for FT3 and FT4 (-r = 0.55-0.56, 0.5-0.54, p < 0.05) in HPRT patients. On the other hand, a reverse pattern was observed, for correlation of Ca and Pb with thyroid functions in HPOT patients.


Assuntos
Cálcio/sangue , Hipertireoidismo/sangue , Hipotireoidismo/sangue , Chumbo/sangue , Hormônios Tireóideos/sangue , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Tireóidea , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue
8.
Sci Total Environ ; 544: 653-60, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26674695

RESUMO

Humans can be exposed to arsenic (As) through air, drinking water, and food. The aim of this study was to calculate the hazard quotient (HQ) of As, based on its concentration in drinking water and the scalp hair of children (males) belonging to two age groups (5-10 and 11-14 years) who consumed water contaminated with different concentrations of As. The water samples were collected from As-exposed and nonexposed areas, which were classified as low-exposed (LE), high-exposed (HE), and nonexposed (NE) areas. The total concentration of inorganic As (iAs) and its species (As(III) and As(V)) in water samples of all selected areas was determined by advanced extraction methods. For purposes of comparison, the total As level was also determined in all water samples. The resulting data indicated that the predominant inorganic As species in groundwater samples was arsenate (As(V)). The As concentrations in drinking water of LE and HE areas were found to be 2.6-230-fold higher than the permissible limit for drinking water established by the World Health Organization (2004). However, the As levels in drinking water of the NE area was within the permissible limit (<10 µg/L). The As levels in the scalp hair samples from boys of NE, LE, and HE areas ranged from 0.16 to 0.36, 0.36 to 0.83, and 11.5 to 31.9 mg/kg, respectively. A significant, positive correlation was observed between the As levels in drinking water and scalp hair samples of children from the HE area, compared with the other two groups (p>0.01). The As toxicity risk assessment based on HQ for the NE, LE, and HE areas corresponded to <10, ≥ 10, and >10, respectively. These HQ values indicated the noncarcinogenic, less carcinogenic, and highly carcinogenic exposure risks faced by children from the NE, LE, and HE areas, respectively. It can be concluded that children consuming the groundwater of the LE (Khairpur Mir's) and HE (Tharparkar) areas of Pakistan are at a potential risk of chronic As toxicity.


Assuntos
Arsênio/análise , Água Potável/química , Exposição Ambiental/análise , Poluentes Químicos da Água/análise , Adolescente , Intoxicação por Arsênico/epidemiologia , Criança , Pré-Escolar , Exposição Ambiental/estatística & dados numéricos , Cabelo/química , Humanos , Masculino , Paquistão/epidemiologia , Medição de Risco
9.
Environ Geochem Health ; 38(1): 265-74, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26003113

RESUMO

The combined exposure to aluminum (Al) and cadmium (Cd) causes more pronounced adverse health effects on humans. The kidneys are the main organs affected by internal exposure to Cd and Al via food and non-food items. The objective of present study was to measure the Al and Cd concentrations in cigarettes tobacco (branded and non-branded) and drinking water (domestic treated, ground and lake water) samples in southern part of Pakistan, to assess the risk due to ingestion of water and inhalation of cigarettes smoke containing high concentrations of both elements. The study population (kidney disorder and healthy) divided into two group based on consuming lake and ground water, while smoking non-branded cigarette as exposed, while drinking domestic treated water and smoking branded cigarette as non-exposed. Electrothermal atomic absorption spectrometry was used to determined Cd and Al concentrations in tobacco, drinking water and blood samples. The resulted data indicated that the levels of Al and Cd in lake and underground water were higher than the permissible limit in drinking water recommended by the World Health Organization. The biochemical parameters of exposed and referent patients, especially urinary N-acetyl-h-glucosaminidase, were used as a biomarkers of kidney disorder. Exposed kidney disorder patients have higher levels of Cd and Al than the exposed referents subjects, while difference was significant when compared to resulted data of non-exposed patients and referents (p = 0.01-0.001). The pearson correlation showed positive correlation between both toxic element concentrations in water, cigarettes versus blood samples of exposed subjects (r = 0.20-0.67 and 0.71-0.82), while lower values were observed for non-exposed subjects (r = 0.123-0.423 and 0.331-0.425), respectively.


Assuntos
Alumínio/sangue , Cádmio/sangue , Água Potável/química , Exposição Ambiental , Nefropatias/epidemiologia , Fumar , Adulto , Monitoramento Ambiental , Feminino , Humanos , Incidência , Nefropatias/sangue , Nefropatias/induzido quimicamente , Modelos Logísticos , Pessoa de Meia-Idade , Razão de Chances , Paquistão/epidemiologia , Prevalência , Risco
11.
Environ Monit Assess ; 187(5): 309, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25930204

RESUMO

The present study was aimed to evaluate the cadmium (Cd) and lead (Pb) levels in the blood samples of adolescent boys, chewing different smokeless tobacco (SLT) products in Pakistan. For comparative purpose, boys of the same age group (12-15 years), not consumed any SLT products were selected as referents. To determine trace levels of Cd and Pb in blood samples, a preconcentration method, vortex-assisted liquid-liquid microextraction (VLLME) has been developed, prior to analysis by flame atomic absorption spectrometry. The hydrophobic chelates of Cd and Pb with ammonium pyrrolidinedithiocarbamate were extracted into the fine droplets of ionic liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate, while nonionic surfactant, Triton X-114 was used as a dispersing medium. The main factors affecting the recoveries of Cd and Pb, such as concentration of APDC, centrifugation time, volume of IL and TX-114, were investigated in detail. It was also observed that adolescent boys who consumed different SLT products have 2- to 3-fold higher levels of Cd and Pb in their blood samples as compared to referent boys (p < 0.001).


Assuntos
Cádmio/sangue , Exposição Ambiental/estatística & dados numéricos , Substâncias Perigosas/sangue , Chumbo/sangue , Tabaco sem Fumaça/estatística & dados numéricos , Adolescente , Monitoramento Ambiental , Humanos , Imidazóis/química , Microextração em Fase Líquida , Masculino , Octoxinol , Paquistão , Polietilenoglicóis/química , Pirrolidinas/química , Espectrofotometria Atômica/métodos , Tiocarbamatos/química
12.
Environ Monit Assess ; 187(6): 350, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25968551

RESUMO

The determination of trace and toxic metals in the biological samples of human beings is an important clinical screening procedure. The aim of the present study was to compare the level of essential trace and toxic elements cadmium (Cd), calcium (Ca), lead (Pb), and magnesium (Mg) in biological samples (whole blood, urine, and scalp hair) of male paralyzed production (PPW) and quality control workers (PQW) of a steel mill, age ranged (35-55 years). For comparison purposes, healthy age-matched exposed referent subjects (EC), working in steel mill and control subjects (NEC), who were not working in industries and lived far away from the industrial areas, were selected as control subjects. The concentrations of electrolytes and toxic elements in biological samples were measured by atomic absorption spectrometry after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked using certified reference materials. The results of this study showed that the mean values of Cd and Pb were significantly higher in scalp hair, blood, and urine samples of PPW and PQW as compared to NEC and EC (p < 0.001), whereas the concentrations of Ca and Mg were found to be lower in the scalp hair and blood but higher in the urine samples of PPW and PQW. The results show the need for immediate improvements in workplace, ventilation, and industrial hygiene practices.


Assuntos
Cádmio/metabolismo , Cálcio/metabolismo , Chumbo/metabolismo , Magnésio/metabolismo , Exposição Ocupacional/estatística & dados numéricos , Paralisia/metabolismo , Adulto , Cádmio/análise , Cálcio/análise , Monitoramento Ambiental , Cabelo/química , Intoxicação por Metais Pesados , Humanos , Chumbo/análise , Magnésio/análise , Masculino , Metalurgia , Exposição Ocupacional/análise , Intoxicação , Controle de Qualidade , Couro Cabeludo , Espectrofotometria Atômica/métodos , Aço
13.
Environ Monit Assess ; 187(3): 82, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25655123

RESUMO

The causes of night blindness in children are multifactorial and particular consideration has been given to childhood nutritional deficiency, which is the most common problem found in underdeveloped countries. Such deficiency can result in physiological and pathological processes that in turn influence biological sample composition. This study was designed to compare the levels of selenium (Se) and mercury (Hg) in scalp hair, blood, and urine of night blindness children age ranged (3-7) and (8-12) years of both genders, comparing them to sex- and age-matched controls. A microwave-assisted wet acid digestion procedure was developed as a sample pretreatment for the determination of Se and Hg in biological samples of night blindness children. The proposed method was validated by using conventional wet digestion and certified reference samples of hair, blood, and urine. The Se and Hg in biological samples were measured by electrothermal atomic absorption spectrometry and cold vapor atomic absorption spectrometry, prior to microwave acid digestion, respectively. The concentration of Se was decreased in scalp hair and blood samples of male and female night blindness children while Hg was higher in all biological samples as compared to referent subjects. The Se concentration was inversely associated with the risk of night blindness in both genders. These results add to an increasing body of evidence that Se is a protecting element for night blindness. These data present guidance to clinicians and other professional investigating deficiency of essential micronutrients in biological samples (scalp hair and blood) of night blindness children.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/metabolismo , Mercúrio/metabolismo , Cegueira Noturna/metabolismo , Selênio/metabolismo , Ácidos , Criança , Pré-Escolar , Exposição Ambiental/análise , Monitoramento Ambiental , Feminino , Cabelo/química , Humanos , Masculino , Mercúrio/análise , Selênio/análise , Espectrofotometria Atômica
14.
Environ Monit Assess ; 187(2): 37, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25632899

RESUMO

The aim of the present study was to evaluate the comparative distribution, correlation, and apportionment of selected elements-aluminum (Al), calcium (Ca), cadmium (Cd), potassium (K), magnesium (Mg), sodium (Na), and lead (Pb)-in the blood samples of male kidney failure patients (KFP) and healthy subjects of age ranged 30-60 years. The blood samples were digested with nitric acid and perchloric acid mixture (2:1), followed by the quantification of elements by atomic absorption spectrometry. The concentration of essential elements in blood samples of KFP were found in the range of Ca (97-125), Mg (18-36), Na (2971-3685), and K (177-270) mg/L while, the levels of Al, Cd, and Pb were found in the range of (475-1275), (0.9-9.9), and (211-623) µg/L, respectively. In the healthy referents, concentration of electrolytes in blood samples was lower than KFP, but difference was not significant (p > 0.05). While the levels of toxic elements in blood samples of referents were three- to sixfold lower than KFP (p < 0.01). Principal component analysis (PCA) and cluster analysis (CA) of the element data manifested diverse apportionment of the selected elements in the blood sample of the KFP compared with the healthy counterparts.


Assuntos
Exposição Ambiental/análise , Poluentes Ambientais/sangue , Substâncias Perigosas/sangue , Insuficiência Renal/sangue , Oligoelementos/sangue , Adulto , Alumínio/análise , Alumínio/sangue , Cádmio/análise , Cádmio/sangue , Cálcio/análise , Cálcio/sangue , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental , Humanos , Magnésio/análise , Magnésio/sangue , Masculino , Pessoa de Meia-Idade , Potássio/análise , Potássio/sangue , Sódio/análise , Sódio/sangue , Espectrofotometria Atômica
15.
J Oral Pathol Med ; 44(9): 707-13, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25359463

RESUMO

BACKGROUND: It has been reported that smokeless tobacco (SLT) chewing can lead to caners of oral cavity. In this study, the relationship between cadmium exposure via consumption of different SLT products by patients with oral cancer with related to referents belongs to different cities of Pakistan are investigated. METHODS: The cadmium in different types of SLT products (gutkha, mainpuri and snuff) consumed by studied population and biological samples (scalp hair and blood) of cancerous and healthy subjects were analyzed. Both referents and patients with cancer have same age group (ranged 30-60 years), socioeconomic status, localities, and dietary habits. The concentrations of cadmium 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. RESULTS: It was estimated that 10 g intake of different types of gutkha, mainpuri, and snuff could contribute, 18-40%, 15.7-33.6%, and 14-68% of the provisional maximum tolerable daily intake of cadmium, respectively for adults (60 kg). The results of present study showed that the mean value of cadmium was significantly higher in scalp hair and blood samples of patients with oral cancer as compared to those results obtained for referents (P < 0.001). CONCLUSIONS: The high exposure of cadmium due to consuming different SLT products may have synergistic effects with other risk factors associated for oral cancer.


Assuntos
Cádmio/metabolismo , Cabelo/química , Neoplasias Bucais/metabolismo , Couro Cabeludo/química , Uso de Tabaco/metabolismo , Tabaco sem Fumaça , Adulto , Análise de Variância , Cádmio/sangue , Estudos de Casos e Controles , Feminino , Cabelo/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/sangue , Neoplasias Bucais/epidemiologia , Neoplasias Bucais/etiologia , Paquistão/epidemiologia , Valores de Referência , Couro Cabeludo/metabolismo , Espectrofotometria Atômica/métodos
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 138: 387-94, 2015 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-25523044

RESUMO

A new approach was developed for the preconcentration of cadmium (Cd) and nickel (Ni) in artificial saliva extract of dry snuff (brown and black) products using temperature-controlled ionic liquid-based ultrasound-assisted dispersive liquid-liquid microextraction (TIL-UDLLµE) followed by electrothermal atomic absorption spectrometry (ETAAS). The Cd and Ni were complexed with ammonium pyrrolidinedithiocarbamate (APDC), extracted in ionic liquid drops, 1-butyl-3-methylimidazolium hexafluorophosphate [C4MIM][PF6]. The multivariate strategy was applied to estimate the optimum values of experimental variables influence the % recovery of analytes by TIL-UDLLµE method. At optimum experimental conditions, the limit of detection (3s) were 0.05 and 0.14µgL(-1) while relative standard deviations (% RSD) were 3.97 and 3.55 for Cd and Ni respectively. After extraction, the enhancement factors (EF) were 87 and 79 for Cd and Ni, respectively. The RSD for six replicates of 10µgL(-1) Cd and Ni were 3.97% and 3.55% respectively. To validate the proposed method, certified reference material (CRM) of Virginia tobacco leaves was analyzed, and the determined values of Cd and Ni were in good agreement with the certified values. The concentration of Cd and Ni in artificial saliva extracts corresponds to 39-52% and 21-32%, respectively, of the total contents of both elements in dry brown and black snuff products.


Assuntos
Cádmio/análise , Líquidos Iônicos , Neoplasias Bucais/induzido quimicamente , Níquel/análise , Saliva Artificial/análise , Adolescente , Adulto , Feminino , Radicais Livres , Humanos , Concentração de Íons de Hidrogênio , Imidazóis/química , Chumbo/química , Ligantes , Masculino , Pessoa de Meia-Idade , Compostos Orgânicos , Saliva , Microextração em Fase Sólida , Temperatura , Tabaco sem Fumaça , Adulto Jovem
17.
Environ Monit Assess ; 186(12): 8611-28, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25223532

RESUMO

In the current study, the chemistry of fresh and stored rainwater of Thar Desert, Pakistan, was estimated during two consecutive monsoon periods. The present research deals with the variation in physicochemical parameters, total arsenic (As(t)), inorganic arsenic species (As(i), As(V), As(III)), and fluoride (F(-)) in stored rainwater (SRW) at different time intervals (1 week to 3 months). The pH of fresh rainwater (FRW) samples showed slightly acidic to neutral in nature (6.08-7.06) which were inconsistent with the reference pH value (5.6) of rainwater. The resulted data indicated that As(t) and F(-) levels in SRW were enhanced with time duration. The levels of As(t) and F(-) in SRW after different time intervals were found in the range of 194-683 µg/L and 10-35.4 mg/L, respectively. The values of As(t) and F(-) were 20-70 and 7-24 times higher than those of WHO permissible limits, 10 µg/L and 1.5 mg/L, respectively. The As(III) was dominant species in SRW, which corresponds to >60 % of As(i). The characteristics of the SRW revealed an unacceptable quality to consume for drinking and agricultural purposes in the studied area.


Assuntos
Arsênio/análise , Fluoretos/análise , Chuva/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Paquistão , Abastecimento de Água/análise , Abastecimento de Água/estatística & dados numéricos
18.
Clin Lab ; 60(8): 1309-18, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25185416

RESUMO

BACKGROUND: The abnormal metabolism of metal ions plays an important role in health and disease conditions, and studies about them have been attracting significant interest. The aim of our study was to assess the toxic elements arsenic (As), cadmium (Cd), nickel (Ni), and lead (Pb) in biological samples (scalp hair, blood, urine) of 387 hypertensive males and females, aged between 30 and 60 years, from an urban population together with 439 non-hypertensive subjects, of the same age group and residential areas. METHODS: The element concentrations were measured by means of an electrothermal atomic absorption spectrophotometer after microwave-induced acid digestion. The validity and accuracy was checked by conventional wet acid digestion method and using certified reference materials. The overall recoveries of all elements were found in the range of 96.8 - 99.4% of certified values. RESULTS: The results indicated significantly higher levels of As, Cd, Ni, and Pb in the biological samples (scalp hair, blood and urine) of hypertensive patients, when related to controls of both genders. CONCLUSIONS: The high exposure of toxic elements may be synergistic with risk factors associated with hypertension. These data present guidance to clinicians and other professionals who will be investigating the toxicity of heavy elements in biological samples (scalp hair and blood) of hypertensive patients.


Assuntos
Arsênio/análise , Cádmio/análise , Cabelo/química , Hipertensão/sangue , Hipertensão/urina , Chumbo/análise , Níquel/análise , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Micro-Ondas , Pessoa de Meia-Idade , Paquistão , Reprodutibilidade dos Testes , Fatores de Risco , Espectrofotometria Atômica , População Urbana
19.
Clin Lab ; 60(8): 1333-41, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25185419

RESUMO

BACKGROUND: The consequence of trace elements deficiency has been associated with an increased risk of human immunodeficiency virus type 1 (HIV-1) disease progression and mortality. This study examined the association between high concentrations of chromium (Cr) and manganese (Mn) in scalp hair, blood, and urine and opportunistic infections in hospitalized patients with the acquired immune deficiency syndrome (AIDS). METHODS: The study was performed on 62 male HIV+ patients (HIV-1) from different cities of Pakistan. The patients were divided in two groups according to secondary infections (tuberculosis, diarrhea, or high fever). The biological samples (scalp hair, blood and urine) were collected from AIDS patients, and for comparative study 120 healthy subjects (males) of same age group (31 - 45 years), socio-economic status, localities, and dietary habits were also included. The elements in the biological samples were analyzed by electrothermal atomic absorption spectrophotometry after microwave-assisted acid digestion. The validity and accuracy of the methodology was checked by using certified reference materials (CRMs) and with the values obtained by conventional wet acid digestion method on the same CRMs. RESULTS: The results indicated significantly lower concentrations of Cr and Mn in the biological samples (scalp hair, blood, and urine) of male HIV-1 patients, compared with control subjects. It was observed that the lower levels of these trace elements may be predictors for secondary infections in HIV-1 patients. There was a significant decrease in mean values of Cr and Mn in whole blood and scalp hair, whilst higher concentrations were observed in urine samples of the three groups of AIDS patients as compared to a controlled healthy male group (p < 0.001). CONCLUSIONS: Low Cr and Mn levels may be due to increased Cr and Mn losses. These data present guidance to clinicians and other professional investigating deficiencies of Cr and Mn in biological samples of AIDS patients.


Assuntos
Cromo/análise , Diarreia , Infecções por HIV , Cabelo/química , Manganês/análise , Tuberculose , Adulto , Estudos de Casos e Controles , Coinfecção/sangue , Coinfecção/urina , Diarreia/sangue , Diarreia/urina , Progressão da Doença , Infecções por HIV/sangue , Infecções por HIV/urina , Humanos , Masculino , Micro-Ondas , Pessoa de Meia-Idade , Paquistão , Padrões de Referência , Couro Cabeludo , Espectrofotometria Atômica , Tuberculose/sangue , Tuberculose/urina
20.
Biol Trace Elem Res ; 160(2): 197-205, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24973874

RESUMO

There is accumulative evidence that the metabolism of iron (Fe) and copper (Cu) is altered in human due to infections, indicating that both elements have roles in pathogenesis and progress of viral diseases. In the present study, the correlation of Cu and Fe was evaluate in biological samples (serum and scalp hair) of hepatitis C (hepatitis C virus (HCV)) patients of both genders at different stages. For comparative study, the scalp hair and serum samples of healthy individuals of same age group (30-50 years) and socioeconomic status were collected. The biological samples were analyzed for Fe and Cu by atomic absorption spectroscopy after microwave-assisted acid digestion. The validity and accuracy of methodology were checked by certified reference materials of same matrixes. The levels of Cu and Fe in biological samples were enhanced in hepatic disorder patients, including acute (after diagnosis test, anti-HCV sero-positive) hepatic fibrosis and liver cirrhosis as compared to healthy referents. The difference was significant (p < 0.01) in the case of liver cirrhotic patients. It was observed that the data of Cu and Fe in referents and patients of both genders had normal distributions. The inter-elemental correlation (r) among Cu vs Fe in serum and scalp hair samples of referents and patients were not significant in both genders (p > 0.1) except in the first stage of HCV (p < 0.1). It was concluded that the increase of Cu and Fe content in human body seems to contribute to the development of cirrhosis in patients with viral hepatitis C.


Assuntos
Cobre/análise , Hepatite C/metabolismo , Ferro/análise , Cirrose Hepática/metabolismo , Adulto , Cobre/sangue , Progressão da Doença , Feminino , Cabelo/química , Hepatite C/sangue , Humanos , Ferro/sangue , Cirrose Hepática/sangue , Masculino , Pessoa de Meia-Idade , Couro Cabeludo , Espectrofotometria Atômica , Fatores de Tempo
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