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1.
Uranium contamination in groundwater at Balod district of Chhattisgarh state was measured by laser fluorimetric technique. Most of the samples were found under safe limit for uranium contamination as recommended by WHO and USEPA (<30 µg l?1) except Deur Tarai village (78.93 µg l?1).The excess lifetime carcinogenic risk and chemical risk due to ingestion of groundwater were calculated using USEPA recommendations.  相似文献   

2.
Traces of uranium were measured by laser fluorimeter in 235 subsurface water samples collected from four districts of Punjab state in India. The concentration of U in water samples ranged between <2–644 μg/L with a mean value of 73.1 μg/L. The radiological risk was observed to be in the range of 5.55 × 10?6–1.78 × 10?3 with a mean value of 2.03 × 10?4, which is around 22% more than the maximum acceptable level (l.67 × 10?4) as per guidelines of India's Atomic Energy Regulatory Board. The mean of chemical toxicity risk, expressed as life time average daily dose (LADD) was worked out to be 5.56 μg/kg/day with a range of 0.15–48 μg/kg/day by considering a bodyweight of 51.5 ± 8.5 kg, water ingestion rate of 4.05 L/d, and life expectancy of 63.7 yrs for an adult Indian reference man and compared with the reference dose (4.53 μg/kg/day). The average exposure level of U was comparatively high and the chemical toxicity was expected to be more. The mean of hazard quotient (LADD/ RfD) for all four districts was found to be greater than 1, indicating that groundwater may not be suitable for consumption from a chemical toxicity point of view.  相似文献   

3.
The present study was conducted to estimate As concentration in groundwater and resulting human health risk in terms of chronic daily intake, hazard quotient (HQ), hazard index (HI), and carcinogenic risk (CR) both for oral and dermal exposure to As. Groundwater samples (n = 100) were collected from ten different towns of Lahore District (Pakistan). Arsenic concentration ranged from 2 to 111 µg L?1 in groundwater samples of the study area, which was significantly greater than the safe limit of As (10 µg L?1) in drinking water set by the World Health Organization. Health risk assessment of As showed that HQ (0.1–11) for oral exposure and HI (0.1–11) values also exceeded the typical toxic risk index value of 1. 9.75 × E-05–4.59 × E-03 and 5.89 × E-07–2.77 × E-05 for oral and dermal As exposure, respectively. Both CR and cancer index (CIs) values were higher than United States Environmental Protection Agency limit (10?6), suggesting that people are at high risk of As-induced carcinogenicity from oral and dermal exposure to As in drinking water. It was concluded that As contamination of groundwater causes carcinogenic and noncarcinogenic health effects to the people; therefore, urgent management and remedial actions are required to protect people from As poisoning.  相似文献   

4.
A flow injection chemiluminescence method is described for the determination of subnanomolar concentrations of vanadium in environmental water samples. The procedure is based on the oxidation of luminol in the presence of dissolved oxygen catalyzed by vanadium(IV). Vanadium(V) reduction and preconcentration of vanadium(IV) was carried out using in‐line silver reductor and 8‐hydroxyquinoline chelating columns at pH 3.15, respectively. The calibration graph for vanadium(IV) was linear in the concentration range of 0.025–10 µg/L with relative standard deviation in the range of 0.4–5.58%. The detection limit (3s blank) was 3.8 × 10?3 µg/L without preconcentration; when the vanadium(IV) was preconcentrated with an 8‐HQ column for 1 min (2.0 mL of sample loaded), the detection limit of 5.1 × 10?4 µg/L was achieved. One analytical cycle can be completed in 2.0 min. The analysis of certified reference materials (CASS‐4, NASS‐5 and SLRS‐4) by the proposed method showed good agreement with the certified values. The method was successfully applied to the determination of total dissolved vanadium in environmental water samples. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

5.
Drinking water contaminated with arsenic poses serious threat to the human health. The present study was aimed for quality assessment of the groundwater of Khairpur Mir's in respect with arsenic and other elemental contamination like Fe, Cu, Co, and Ni. The presence of the trace elements in groundwater from different sources in the study area was measured by using atomic absorption spectroscopy. For arsenic analysis hydride generation technique (MHS-15) was used with detection limit of 0.02 µg l?1. Elevated level of arsenic was observed in most of the samples as compared to recommended value of World Health Organization (WHO) guidelines (10 µg l?1). However, levels of Fe, Cu, Co, and Ni in hand pump (HP) water samples was found in the range of 4–1610 µg l?1, 0–556 µg l?1, 0–230 µg l?1, and 0–700 µg l?1, respectively. Whereas in tube well (TW) water samples the observed values are 5–1620 µg l?1, 0–50 µg l?1, 4–110 µg l?1, and 0–360 µg l?1 for Fe, Cu, Co, and Ni, respectively. Significant difference was observed between TW and HP water samples. It was concluded that the level of arsenic found was very high up to 13 fold more than the WHO recommended limit in study area. While the levels of other elements was noted within the safe limit.  相似文献   

6.
Abstract

This study was performed to measure arsenic (As) contents in groundwater/drinking water of high schools and its effects on human health. Chronic daily intake, hazardous quotient (HQ), carcinogenic risk (CR), hazardous index (HI), and carcinogenic indices (CI) for oral and dermal exposure to arsenic were calculated. Samples were taken from high schools in four tehsils of Multan. As contents ranged from 3.25 to 184?µg/l and 99% samples exceeded World Health Organization safe limit (10?µg/l). HQ for Multan city (1.70) and for Multan Saddar (1.38) exceeded USEPA permissible toxic risk value (1.0). CR in four tehsils for oral (0.0001–0.0003) and dermal exposure (0.0000049–0.000011) exceeded USEPA limit (10?6). HI for tehsil Multan city (1.75) and Multan Saddar (1.42) exceeded the limit (1.0). CI for four tehsils ranged from 0.00022 to 0.0008 exceeding USEPA limit (10?6) indicating high chronic and carcinogenic health risk to exposed population. Results indicated that groundwater of district Multan is not fit for human consumption due to excessive arsenic contamination. It invites attention of water supplying agency and educational authorities to take steps for provision of arsenic free safe drinking water to students and local area peoples.  相似文献   

7.
Groundwater is the main source of drinking water in both rural and urban areas of the Pratapgarh district in the eastern Uttar Pradesh. Fifty-five groundwater samples were collected from 17 blocks of the Pratapgarh district and analyzed for fluoride (F?) and other water quality parameters (pH, EC, TDS, turbidity, Cl?, HCO3?, SO42?, NO3?, Ca2+, Mg2+, Na+, K+, silica and total hardness) to assess its suitability for drinking uses. The fluoride concentration in the analyzed groundwater of the Pratapgarh district varied between 0.41 and 3.99 mg/L. Fluoride concentration in about 78% of the groundwater samples exceeded the acceptable level of 1.0 mg/L, while in 70% samples it exceeded the maximum permissible limit of 1.5 mg/L. A geographic information system (GIS) tool was used to study the spatial variation of fluoride concentrations in the groundwater of the Pratapgarh district. Fluoride is positively correlated with pH (0.36) and HCO3? (0.22) and negatively with Ca2+ (?0.23) and Mg2+ (?0.08), suggesting dissolution of fluoride-bearing minerals with the precipitation of Ca/Mg carbonate in the alkaline environment. The maximum exposure dose to fluoride for adults in the study area was found to be 6.8 times higher than the minimum risk level (MRL) of 0.05 mg kg?1 day?1 estimated by the Agency for Toxic Substances and Disease Registry (ATSDR).  相似文献   

8.
This study was aimed to examine the risk of chronic arsenic (As) exposure for the residents living in Nui Phao, Thai Nguyen in the northern Vietnam. Groundwater, vegetables, human hair, and nail samples were collected from volunteers living in Nui Phao. The results revealed that 75% of the groundwater samples had As exceeding the World Health Organization (WHO) drinking water guideline of 10 µg L?1. The result of As concentration for most of the vegetable samples was greater than the WHO/FAO safe (0.1?mg kg?1). The result of hair and nail samples in this study showed that 3.5 and 20% of the samples had As concentration exceeding the level of As toxicity in hair and nails, respectively. The result of health risks indicated that the potential health risk of As contamination is greater for groundwater than vegetables. The total hazard quotient (HQ) value through vegetables ingestion and drinking water exceeded 1.0 suggesting potential health risk for local residents. The calculation of potential carcinogenic risk through both consumption of vegetables and drinking water was low cancer risk in adults. Other food sources and the exposure pathways are needed to exactly assess health risks in this area.  相似文献   

9.
The present study was aimed at assessing drinking water quality regarding arsenic (As) and its impact on health from Mailsi (Punjab), Pakistan. Forty-four groundwater samples were collected from two sites, Sargana and Mailsi. Arsenic and other cations were determined by atomic absorption spectrophotometer, whereas the anions were determined either through titration or spectrophotometer. The results revealed that dominant anions were HCO3? and Cl?, Ca+2 was the dominant cation, and overall water chemistry of the area was CaMgHCO3? type. Arsenic concentrations were high, ranging from 11 to 828 µg/L that crossed the World Health Organization permissible limits. Likewise, higher SO4?2 concentrations ranging from 247 to 1053 mg/L were observed. The health risk index was higher in the Sargana site, which employed the differences in terms of higher Average Daily Dose, Hazard Quotient, and Carcinogenic Risk of arsenic, which is unsuitable for drinking purposes. The area seems to be at high risk due to arsenic pollution and wells have never been tested for arsenic concentrations earlier; therefore, necessary measures should be taken to test the wells with respect to arsenic.  相似文献   

10.
By taking advantage of microflow injection chemiluminescence analysis, we developed a distinctive microfluidic bioassay method based on G‐Quadruplex DNAzyme‐enhanced chemiluminescence for the determination of K+ in human serum. AGRO100, the G‐rich oligonucleotide with high hemin binding affinity was primarily selected as a K+ recognition element. In the presence of K+, AGRO100 folded into G‐quadruplex and bound hemin to form DNAzyme, which catalyzed the oxidation of luminol by H2O2 to produce chemiluminescence. The intensity of chemiluminescence increased with the K+ concentration. In the study, the DNAzyme showed both long‐term stability and high catalytic activity; other common cations at their physiological concentration did not cause notable interference. With only 6.7 × 10?13 mol of AGRO100 consumption per sample, a linear response of K+ ranged from 1 to 300 µmol/L, the concentration detection limit 0.69 µmol/L (S/N = 3) and the absolute detection limit 1.38 × 10?12 mol were obtained. The precision of 10 replicate measurements of 60 µmol/L K+ was found to be 1.72% (relative standard deviation). The accuracy of the method was demonstrated by analyzing real human serum samples. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

11.
A novel, sensitive and rapid CL method coupled with high‐performance liquid chromatography separation for the determination of carbamazepine is described. The method was based on the fact that carbamazepine could significantly enhance the chemiluminescence of the reaction of cerium sulfate and tris(2,2‐bipyridyl) ruthenium(II) in the presence of acid. The chromatographic separation was performed on a Kromasil® (Sigma‐Aldrich) TM RP‐C18 column (id: 150 mm × 4.6 mm, particle size: 5 µm, pore size: 100 Å) with a mobile phase consisting of methanol–water‐glacial acetic acid (70:29:1, v/v/v) at a flowrate of 1.0 mL/min, the total analysis time was within 650 s. Under optimal conditions, CL intensity was linear for carbamazepine in the range 2.0 × 10?8 ~ 4.0 × 10?5 g/mL, with a detection limit of 6.0 × 10?9 g/mL (S/N = 3) and the relative standard detection was 2.5% for 2.0 × 10?6 g/mL (n = 11). This method was successfully applied to the analysis of carbamazepine in human urine and serum samples. The possible mechanism of the CL reaction is also discussed briefly. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

12.
A novel chemiluminescence method for the determination of 6‐mercaptopurine was established based on 6‐mercaptopurine inhibition of the chemiluminescence emission of potassium permanganate–thioacetamide–sodium hexametaphosphate system. The peak height was proportional to log 6‐mercaptopurine concentration in the range 7.0 × 10?10 to 1.0 × 10?7 g/mL and the detection limit was 1.9 × 10?11 g/mL (S/N = 3). The relative standard deviation was 1.5% for the determination of 8.0 × 10?8 g/mL 6‐mercaptopurine (n = 11). The proposed sensor was successfully applied to the analysis of 6‐mercaptopurine in human serum samples. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

13.
A rapid, simple, inexpensive and highly sensitive spectrofluorimetric method was developed for the determination of trace amounts of some tetracyclines (TCs), namely tetracycline hydrochloride (TCH), oxytetracycline hydrochloride (OTCH) and minocycline hydrochloride (MCH). Binding rhodamine B (RhB) to gold nanoparticles (Au NPs) resulted in quenching of the fluorescence of RhB by a resonance energy transfer (FRET) mechanism, with Au NPs as the energy acceptors. The presence of TCs caused the release of RhB molecules and recovered their fluorescence, and this was used as a basis for the quantitative determination of TCs. The reaction was monitored spectrofluorimetrically by measuring the increase in fluorescence of RhB at 572 nm starting 5 min after mixing the reagents in Tris buffer solution (pH 6.5). The effect of various experimental factors such as buffer type, pH, concentrations of the involved reagents and reaction time were studied to optimize the reaction conditions. Under optimum conditions, the calibration graphs were linear within the ranges 2.08 × 10?9–1.04 × 10?6 mol/L, 2.01 × 10?9–1.00 × 10?6 mol/L and 2.02 × 10?9–1.01 × 10?6 mol/L and detection limits (LODs) of 0.61 × 10?9, 0.32 × 10?9 and 0.66 × 10?9 mol/L were calculated for TCH, OTCH and MCH, respectively, with corresponding percent relative standard deviations (%RSDs) of 1.18, 1.21 and 1.54 (n = 5). The method was successfully applied to the determination of TCs in drinking water, human urine, bovine milk and breast milk samples. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

14.
The presence of radon in drinking water causes radiation-related health hazards both through inhalation and ingestion. In the present study, 28 drinking water samples from natural flowing springs, freshwater ponds, and deep hand pumps were analyzed in the fault zone of Reasi region of Jammu &; Kashmir. Radon measurement was performed using the RAD7 electronic device for radon content determination. Average mean values of these samples vary from 2.80 ± 0.78 to 74.37 ± 2.76 Bq l?1. Nineteen drinking water samples analyzed have radon levels in excess of USEPA recommended maximum contamination level of 11.1 Bq l?1. The annual effective dose from radon in water due to its ingestion and inhalation per individual has also been calculated. Uranium concentration in these water samples was also analyzed for a possible correlation between different types of rocks and values of radon in water. Results obtained have been compared with the results of earlier investigators for mean radon concentration and mean annual effective dose for radon in water from different regions of northern India and Pakistan. It has been found that radon levels in a significant number of water samples collected from the region of fault line are higher than USEPA recommendations. A positive correlation is observed between the depth of the water source and the values of radon levels in water samples collected from these sources. Measurements of radon concentration in these water samples were also performed with a Smart Radon Monitor designed by Bhabha Atomic Research Centre, Trombay, Mumbai, India, for a comparative analysis.  相似文献   

15.
Introduction – Honokiol and magnolol are the active components of Magnolia officinalis, which is a widely used traditional Chinese medicine. Their simultaneous analysis is, therefore, important for the quality control of the product. Objective – To establish a simple, sensitive and rapid electrochemical method for the simultaneous detection of honokiol and magnolol based on the remarkable enhancement effect of acetylene black nanoparticle (AB). Methodology – The AB‐modified electrode was prepared via solvent evaporation. The electrochemical response of honokiol and magnolol was investigated using cyclic voltammetry. The simultaneous detection was performed with differential pulse voltammetry. The method was validated in terms of linearity, sensitivity, precision and accuracy. Results – The linear range for honokiol is 0.5–300 µg/L, and the limit of detection (LOD) is 0.25 µg/L (9.4 × 10?10 mol/L). For magnolol, the linear range is 10–250 µg/L, and the LOD is 5 µg/L (1.88 × 10?8 mol/L). Conclusion – The new method was successfully used to determine honokiol and magnolol in a traditional Chinese medicine called Ageratum liquid. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

16.
Abstract

The present study was conducted to assess the magnitude and health impacts of As in drinking water. Drinking water samples (n?=?60) were collected from twenty different sites of Shiekhupura District (Pakistan). Health risk assessment through average daily dose (ADD), hazard indices (HI), hazard quotient (HQ), carcinogenic risk (CR), and cancer indices (CI) for dermal and oral exposure were determined. Results revealed that As concentration ranged from 2 to 900?µg?L?1 in water samples, which was significantly greater than the safe limit of As (10?µg?L?1) in water. Health risk assessment of As showed that ADD (1.07E?02–9.85E?04), HQ (1.06E+01–9.85E+00), and CR (1.60E?02–9.85E?04) for oral exposure and ADD (1.03E?05–9.69E?06), HQ (1.19E?02–7.96E?03), and CR (1.11E?05–8.98E?05) for dermal exposure which were exceeded the toxic risk index value. Comparison of the two exposure pathways indicated that the oral exposure is much higher risk than the dermal contact. Both values of HI and CI were greater than WHO limit. It is concluded that residents of study area are at higher risk of As induced diseases and carcinogenicity.  相似文献   

17.
To manage public health and make better use of groundwater resources, the concentration characteristics and a health risk assessment of eight heavy metals in shallow groundwater were studied. Besides this, this paper introduced triangular fuzzy numbers into the USEPA health risk assessment model to assess the health risk posed to local children and adults through different exposure pathways. The results showed that Mn levels exceeded the WHO’s guideline values of 100?µg/L with the proportion of 27.98% and Sr were over the health reference level (HRL) of 1500?µg/L with the proportion of 56.25%, while other heavy metals were below the corresponding standard. The results of the HRA showed that the non-carcinogenic risks from Sr and Mn in the district were relatively higher, while those from the remaining six heavy metals were relatively lower. All hazard index (HI) values did not exceed the safety level of 1 for either age group. The average carcinogenic risk from Cr was slightly higher than the acceptable level of 1?×?10?6 for adults. Sensitivity analyses conducted using Monte Carlo simulation indicated that Sr and Cr concentrations were the most influential variables contributing to the non-carcinogenic and carcinogenic risk values, respectively, while body weight had a minor contribution.  相似文献   

18.
Based on the oxidation of acridine yellow by permanganate in basic medium, a new chemiluminescence system was developed for the sensitive determination of some important drugs. The remarkable inhibiting effect of fluvoxamine, ceftriaxone and isoniazid on this reaction was applied to their detection. A possible mechanism was proposed for this system based on chemiluminescence emission wavelengths and experimental observations. Under optimum conditions, calibration graphs were obtained for 1 × 10?9 to 1 × 10?6 mol/L of fluvoxamine; 2 × 10?8 to 8 × 10?6 mol/L of ceftriaxone and 5 × 10?8 to 4 × 10?5 mol/L of isoniazid. This proposed method was satisfactorily used in the determination of these drugs in pharmaceutical samples and human urine and serum. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

19.
It was found that meloxicam could enhance the chemiluminescence (CL) of the tris(2,2'‐bipyridine) ruthenium(II)–Ce(IV) system in the medium of sulfate acid. Based on this phenomenon a new flow‐injection system with chemiluminescent detection has been proposed for determination of meloxicam. Under optimum conditions, meloxicam had a good linear relationship with the CL intensity in the concentration range of 6.0  10?4 to 1.0 µg/mL and the detection limit was 3.7 × 10?4 µg/mL. The proposed method was applied to detect meloxicam in tablets and a satisfactory recovery was obtained. The possible mechanism for this CL system is also discussed in this paper. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

20.
A novel flow‐injection chemiluminescence method was developed for the selective determination of human immunoglobulin G (IgG) in the presence of thiomersal by changing the flow rates of peristaltic pump. The study was based on the independence and additivity of the CL signals of human IgG and thiomersal in the galangin–potassium permanganate–polyphosphoric acid system. In meantime, two equations relating to the concentrations of mixing solutions of human IgG and thiomersal vs the CL intensity were established and solved, on the basis of which the content of thiomersal included in samples was simultaneously determined too. The enhanced CL intensity was in proportion to concerntrations in the range 8.0 × 10?7 to 8.0 × 10?5 g/mL for human IgG and 1.0 × 10?7 to 2.0 × 10?6 g/mL for thiomersal with the detection limits of 5.0 × 10?7 g/mL for human IgG and 6.0 × 10?8 g/mL for thiomersal, respectively. The relative standard deviation for 1.0 × 10?5 g/mL human IgG was 0.8% and for 2.0 × 10?7 g/mL thiomersal it was 2.0% (n = 10). The proposed method was applied to determine three synthetic samples with recoveries of 91.5–109.5%. In addition, the possible chemiluminescence mechanisms are discussed as well. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

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