Muhammad Balal Arain

Heavy metal accumulation in different varieties of wheat (Triticum aestivum L.) grown in soil amended with domestic sewage sludge

The concentrations of heavy metals (HMs) in plants served to indicate the metal contamination status of the site, and also revealed the abilities of various plant species to take up and accumulate them from the soil dressed with sewage sludge. A study to comprehend the mobility and transport of HMs from soil and soil amended with untreated sewage sludge to different newly breaded varieties of wheat (Anmol, TJ-83, Abadgar and Mehran-89) in Pakistan. A pot-culture experiment was conducted to study the transfer of HMs to wheat grains, grown in soil (control) and soil amended with sewage sludge (test samples). The total and ethylenediaminetetraaceticacid (EDTA)-extractable HMs in agricultural soil and soil amended with domestic sewage sludge (SDWS) and wheat grains were analysed by flame atomic absorption spectrometer/electrothermal atomic absorption spectrometer, prior to microwave-assisted wet acid digestion method. The edible part of wheat plants (grains) from test samples presented high concentration of all HMs understudy (mgkg(-1)). Significant correlations were found between metals in exchangeable fractions of soil and SDWS, with total metals in control and test samples of wheat grains. The bio-concentration factors of all HMs were high in grains of two wheat varieties, TJ-83 and Mehran-89, as compared to other varieties, Anmol and Abadgar grown in the same agricultural plots.

The correlation of arsenic levels in drinking water with the biological samples of skin disorders.

Arsenic (As) poisoning has become a worldwide public health concern. The skin is quite sensitive to As and skin lesions are the most common and earliest nonmalignant effects associated to chronic As exposure. In 2005-2007, a survey was carried out on surface and groundwater arsenic contamination and relationships between As exposure via the drinking water and related adverse health effects (melanosis and keratosis) on villagers resides on the banks of Manchar lake, southern part of Sindh, Pakistan. We screened the population from arsenic-affected villages, 61 to 73% population were identified patients suffering from chronic arsenic toxicity. The effects of As toxicity via drinking water were estimated by biological samples (scalp hair and blood) of adults (males and females), have or have not skin problem (n=187). The referent samples of both genders were also collected from the areas having low level of As (<10 microg/L) in drinking water (n=121). Arsenic concentration in drinking water and biological samples were analyzed using electrothermal atomic absorption spectrometry. The range of arsenic concentrations in lake surface water was 35.2-158 microg/L, which is 3-15 folds higher than World Health Organization [WHO, 2004. Guidelines for drinking-water quality third ed., WHO Geneva Switzerland.]. It was observed that As concentration in the scalp hair and blood samples were above the range of permissible values 0.034-0.319 microg As/g for hair and <0.5-4.2 microg/L for blood. The linear regressions showed good correlations between arsenic concentrations in water versus hair and blood samples of exposed skin diseased subjects (R2=0.852 and 0.718) as compared to non-diseased subjects (R2=0.573 and 0.351), respectively.

Evaluation of arsenic and other physico-chemical parameters of surface and ground water of Jamshoro, Pakistan

Arsenic contamination in water has caused severe health problems around the world. The purpose of this study was to evaluate the geological and anthropogenic aspects of As pollution in surface and groundwater resources of Jamshoro Sindh, Pakistan. Hydride generator atomic absorption spectrophotometry (HG-AAS) is employed for the determination of arsenic in water samples, with detection limit of 0.02 microg l(-1). Arsenic concentrations in surface and underground water range from 3.0 to 50.0, and 13 to 106 microg l(-1), respectively. In most of the water samples As levels exceeded the WHO provisional guideline values 10 microg l(-1). The high level of As in under study area may be due to widespread water logging from Indus river irrigation system which causes high saturation of salts in this semi-arid region and lead to enrichment of As in shallow groundwater. Among the physico-chemical parameters, electrical conductivity, Na(+), K(+), and SO(4)(2-) were found to be higher in surface and ground water, while elevated levels of Ca(2+) and Cl(-) were detected only in ground water than WHO permissible limit. The high level of iron was observed in ground water, which is a possible source of As enrichment in the study area. The multivariate technique (cluster analysis) was used for the elucidation of high, medium and low As contaminated areas. It may be concluded that As originate from coal combustion at brick factories and power generation plants, and it was mobilized promotionally by the alkaline nature of the understudy groundwater samples.

Evaluation of Toxic Metals in Blood and Urine Samples of Chronic Renal Failure Patients, before and after Dialysis

The determination of toxic elements in the biological samples of human beings is an important clinical screening procedure. The aim of this work was to determine total content of toxic elements—aluminum (Al), cadmium (Cd), and lead (Pb)—in whole blood and urine samples of male chronic renal failure patients (CRFPs) on maintenance hemodialysis from 2006 to 2007. The study included 100 CRFPs, plus 150 healthy volunteers in the control group. The concentration of toxic elements (TEs) were determined in blood sample before and after hemodialysis, while urine sample was determined once, before dialysis. Toxic elements were analyzed by electrothermal atomic absorption spectrometer, prior to microwave-induced acid digestion. The accuracy of the total Al, Cd, and Pb measurements was tested by simultaneously analyzing certified reference materials. No significant differences were established between the analytical results and the certified values (paired t-test at p > 0.05). The levels of TEs in blood samples of patients before dialysis were found to be higher than blood samples after dialysis session. In the control group, the blood levels of Al, Cd, and Pb were significantly lower than the chronic renal failure patients. Moreover, the study shows that analyzing levels of Al, Cd, and Pb may be useful in hemodialysis patients in evaluating TEs status.

Arsenic fractionation in sediments of different origins using BCR sequential and single extraction methods.

The arsenic (As) contaminated sediment serves as a long-term source of arsenic because its mobility and transport in the environment are strongly influenced to associated solid phase. A single extraction method based on the reagents employed in the BCR three steps sequential extraction scheme (BCR-SES) for partitioning of arsenic (As) in sediment samples has been developed. The single-step extraction enabled a reduction of extraction times, yielding extractable contents in accordance with those obtained by application of the BCR-SES, which can be regarded as a standard method and validated by using certified reference material BCR 701. The extractable As content associated with different phases in sediment samples were analysed by electrothermal atomic absorption spectrophotometer. The extraction efficiency of As by single-step extraction was slightly higher than BCR-SES, ranged (100-104%), while difference was not significant at 95% confidence limit with <10% precision. The sediment samples from different origins varied in their physico-chemical properties and total As content. The relative mobility of As obtained from different origins was found in increasing order as: acid soluble fraction<oxidizable fraction<reducible fraction. The acid soluble fraction of As was higher in lake sediment samples as compared to those of canal and river sediments, indicating the contamination of lake ecosystem.

Cloud point extraction for determination of lead in blood samples of children, using different ligands prior to analysis by flame atomic absorption spectrometry: A multivariate study

The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of lead (Pb(2+)) from digested blood samples after simultaneous complexation with ammonium pyrrolidinedithiocarbamate (APDC) and diethyldithiocarbamate (DDTC) separately. The complexed analyte was quantitatively extracted with octylphenoxypolyethoxyethanol (Triton X-114). The multivariate strategy was applied to estimate the optimum values of experimental factors. Acidic ethanol was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometer (FAAS). The detection limit value of Pb(2+) for the preconcentration of 10 mL of acid digested blood sample was 1.14 μg L(-1). The accuracy of the proposed methods was assessed by analyzing certified reference material (whole blood). Under the optimized conditions of both CPE methods, 10 mL of Pb(2+) standards (10 μg L(-1)) complexed with APDC and DDTC, permitted the enhancement factors of 56 and 42, respectively. The proposed method was used for determination of Pb(2+) in blood samples of children with kidney disorders and healthy controls.

Respiratory effects in people exposed to arsenic via the drinking water and tobacco smoking in southern part of Pakistan

In this study, a survey has been conducted during 2005-2007 on surface and groundwater arsenic (As) contamination and its impact on the health of local population, of villages located on the banks of Manchar lake, southern part of Sindh, Pakistan. We have also assessed the relationship between arsenic exposure through respiratory disorders in male subjects with drinking water and smoking cigarettes made from tobacco grown in agricultural land irrigated with As contaminated lake water. The biological samples (blood and scalp hair) were collected from As exposed subjects (100% smokers) and age matched healthy male subjects (40.2% smoker and 59.8% non smokers) belong to unexposed areas for comparison purposes. The As concentration in drinking water (surface and underground water), agricultural soil, cigarette tobacco and biological samples were determined by electrothermal atomic absorption spectrometry. The range of As concentrations in lake water was 35.2-158 microg/L (average 97.5 microg/L), which is 3-15 folds higher than permissible limit of World Health Organization (WHO, 2004). While the As level in local cigarette tobacco was found to be 3-6 folds higher than branded cigarettes (0.37-0.79 microg/g). Arsenic exposed subjects (with and without RD) had significantly elevated levels of As in their biological samples as compared to referent male subject of unexposed area. These respiratory effects were more pronounced in individuals who had also As induced skin lesions. The linear regressions showed good correlations between As concentrations in water versus hair and blood samples of exposed subjects with and without respiratory problems.

Simultaneously determination of methyl and inorganic mercury in fish species by cold vapour generation atomic absorption spectrometry

A simple and rapid non-chromatographic method was developed to determine methylmercury (MeHg) and inorganic mercury (iHg) levels in muscles tissues of 10 freshwater fish species. The MeHg and iHg were determined by cold vapour atomic absorption spectrometry after alkaline wet digestion of samples. The digested samples were reduced sequentially with stannous chloride and sodium tetrahydroborate for iHg and MeHg, respectively. Parameters such as carrier gas flow rate (argon), volume of oxidizing and potassium persulphate solutions were investigated in detail. The accuracy of the technique was evaluated by using certified reference material (DORM-2) and spiking the both Hg species in muscles tissue of a fish. The limits of detection were 0.117 and 0.133 μg kg(-1) for MeHg and iHg, respectively. The concentrations of MeHg and iHg in muscles tissues of ten fish species were found in the range of (28.4-56.3) and (3.01-8.11) μg kg(-1), respectively.

Fluoride and arsenic exposure through water and grain crops in Nagarparkar, Pakistan.

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).

Interaction of cadmium and zinc in biological samples of smokers and chewing tobacco female mouth cancer patients.

Epidemiologic studies suggest that zinc (Zn) deficiency and high accumulation of cadmium (Cd) may be associated with increased risk of cancer. The incidence of mouth cancer has increased among females, who possess habits of chewing tobacco with gradients (areca nut and betel quid) and smoking tobacco in Pakistan. In present study, we measured the concentration of Cd and Zn in 96 mouth cancer patients (MCPs) and 110 female controls/referents (67 smoker and chewing tobacco), while 43 have none of smoking and chewing tobacco habits, belongs to different cities of Pakistan. Both controls and patients have same age group (ranged 35-65 years), socio-economic status, localities and dietary habits. The Zn and Cd were determined by flame/graphite furnace atomic absorption spectrophotometer, prior to microwave assisted acid digestion method. The Cd/Zn ratio in both biological samples was also calculated. The results of this study showed that the mean value of Zn was lower, while the mean concentration of Cd was higher in the blood and scalp hair samples of MCPs as compared to control subjects (p<0.001). The controls chewing and smoking tobacco have high level of Cd in both biological samples as compared to those have not smoking or chewing tobacco (p<0.012). The Cd/Zn ratio was higher in MCPs than control subjects. This study is compelling evidence in support of positive associations between cadmium, cigarette smoking, deficiency of Zn and cancer risk.