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1.
A solid phase extraction method for the determination of gold(III) at trace levels by flame atomic absorption spectrometer (FAAS) was developed. The method was based on retention of gold as chloro complexes through the Amberlite XAD-2000. The effect of some analytical parameters including hydrochloric acid concentration, sample volume, sample and eluent flow rates, eluent volume, eluent concentration and interfering ions on the recovery of gold(III) was investigated. The retention of gold(III) from 1.5 mol l−1 HCl solution and the recovery of gold with 0.07 mol l−1 NH3 solution were quantitative (≥95%). The relative standard deviation (RSD) was calculated as 3.2% (n = 10). The detection limit for gold was 2 μg l−1. The accuracy was checked with the determination of gold spiked an artificial seawater and a pure copper samples.  相似文献   

2.
A membrane extraction-gas chromatography method was developed fordetermination of organophosphorus pesticides and related compounds including methamidophos, DDVP, dimethoate, methyl parathion, parathion, thiophosphoric acid trimethyl ester, and thiophosphoramidic acid dimethyl ester in water samples. In thismethod, surface-modified acetic cellulose membranes were used to extract the target analytes in water samples, the extracted analytes were back-extracted into a small amount of methanol, andgas chromatography with pulsed flame photometric detector (GC-PFPD) was used to determine the concentrations of targetanalytes in the extracts. The recoveries obtained for thetarget analytes spiked into the water samples ranged from 66to 94%. The method detection limit for each target analyte was 0.05 g L-1. The method developed in this study had shown the advantages of being cheap, simple, fast, and reliable. It had been used successfully to determine the concentrations of target analytes in river water samples.  相似文献   

3.
A method for the determination of residues of mesotrione, atrazine and its degradation products: deethylatrazine, hydroxyatrazine, deisopropylatrazine, desethyldesisopropylatrazine in a variety of water and soil matrices has been developed. Mesotrione is a new selective herbicide for use in corn, which has been substituted for atrazine, which has been banned in European Union countries since 2007. Although atrazine has not been used for three vegetative periods, it is still detected in the environment. The analysis was conducted by means of ultra-high-pressure liquid chromatography with ultraviolet detection and liquid chromatography with diode array detection. The procedures for analyte separation from water and soil matrices were also established. The optimal conditions for solid-phase extraction (SPE) were determined. The recoveries were compared with that obtained by means of SPE. Method fortification recoveries from water samples averaged 78–97% and for soil 80–97% depending on the analyte and type of sample. The limits of detection were 0.04–0.61 μg/L for water samples and for soil samples 0.02–0.88 μg/g. The soil samples were collected in spring 2009 from three different fields with water samples being made from effluents from these fields. Samples collection was conducted in the day of mesotrione (Callisto 100SC) application and then done weekly, until the mesotrione concentration was below the limit of quantification. The results enabled the monitoring of mesotrione degradation in soil and its permeability into surface waters; simultaneously, the same studies were conducted for atrazine.  相似文献   

4.
Concentrations of polycyclic aromatic hydrocarbons (PAHs) in street soil dust from streets in Kumasi Metropolis in the Ashanti Region of the Republic of Ghana have been measured in this study. The concentrations of the various types of PAHs identified in this study are as follows: Naphthalene (m/e 128) – 41,700 μg/kg, Acenaphthylene (m/e 152) – 99,300 μg/kg, Acenaphthene (m/e 154) – 111,200 μg/kg, Fluorene (m/e 166) – 8,900 μg/kg, Carbazole (m/e 167) – 3,500 μg/kg, phenathrene (m/e 178) – 12,900 μg/kg, Anthracene (m/e 178) – 5,400 μg/kg, Fluoranthene (m/e 202) – 16,200 μg/kg, Pyrene (m/e 202) – 15,000 μg/kg, Benzo[a]anthracene (m/e 228) – 13,800 μg/kg, Chrysene (m/e 228) – 33,600 μg/kg, Benzo[k]fluoranthene (m/e 252) – 45,700 μg/kg, Benzo[a]pyrene (m/e 252) – 27,900 μg/kg, Perylene (m/e 252) – 57,200 μg/kg and Benzo[g, h, i]perylene (m/e 276) – 47,000 μg/kg. The results of the study shows that road users, like resident living in buildings within these areas, those engaged in commercial activities like hawking, and the general public are at risk of exposure to the toxic effects of the various types of PAHs from the exhaust of vehicles into the environment. According to these results, there is the potential for exposure to high levels of PAHs for road users and those living in urban environments or along highways.  相似文献   

5.
Using nitric acid-perchloric acid wet digestion based FAAS method ten selected metals (Cd, Co, Cr, Fe, K, Mn, Na, Ni, Pb and Zn) were determined in the scalp hair of male Pakistani and Libyan donors (n = 62), between 3–54 years age and residing in typical urban areas. The study was taken up to identify sources of metal distribution in two diverse population segments exposed to different environments. Sodium emerged with the highest mean hair concentration of 511.0 μg/g and 496.9 μg/g for Libyan and Pakistani donors respectively, followed by K, at 266.2 μg/g and 242.4 μg/g for the two donor categories. Cadmium showed the lowest mean hair concentration for both Pakistani (0.380 μg/g) and Libyan (0.530 μg/g) donors. Levels of Na, K, Pb, Cr and Cd were higher in hair of Libyan donors compared with Pakistani counterparts which showed higher comparative levels of Zn, Fe, Co, Ni and Mn. Strong metal-to-metal correlations were found between Na–K (r = 0.638) and Cd–Co (r = 0.574) for Pakistani donors, while for Libyan donors, Na–K (r = 0.680) and Fe–Mn (r = 0.624) correlations emerged as strongly significant. Only K was found to have a strong positive correlation (r = 0.611) with age for Pakistani donors while this correlation was significantly negative (r = −0.500) for Libyan donors, probably arising from individual food habits. Other metals showed no viable relationship with age. Principal Component Analysis (PCA) and Cluster Analysis (CA) of the data evidenced food, industrial emissions and automobile emissions as possible sources of metal distribution. The results of the present study are compared with those reported for subjects from other regions of the world.  相似文献   

6.
The implications of metal contamination of agricultural soils due to long term irrigation with treated industrial wastewater and their subsequent accumulation in the vegetables/crops growing on such soils has been assessed in an area of industrial complex, Jajmau, Kanpur (India). Physico-chemical properties of the soil were also studied. The soil and vegetables/crops were sampled from an area of 2100 acre agricultural land and analyzed for physico-chemical properties and metal accumulation in different parts of the plants. The comparison of the data of physico-chemical properties of control and contaminated soil showed that salinity, electrical conductivity, available phosphorous, sodium and potassium content (both water soluble and exchangeable) were found high in contaminated soil. The analysis of plant available metal content in the soil showed the highest level of Fe, which ranged from 529.02 to 2615 μg g−1 dw and lowest level of Ni (3.12 to 10.51 μg g−1 dw). The analysis of the results revealed that accumulation of toxic metal Cr in leafy vegetables was found more than fruit bearing vegetables/crops. Thus, it is recommended that the leafy vegetables are unsuitable to grow in such contaminated sites. It is important to note that toxic metal, Ni was not detected in all the plants. The edible part of the vegetables (under ground) such as, garlic (19.27 μg g−1 dw), potato (11.81 μg g−1 dw) and turmeric (20.86 μg g−1 dw) has accumulated lowest level of toxic metal, Cr than leafy and fruit bearing vegetables. In some fruit part of vegetables such as, bitter gourd, egg plant, jack tree, maize and okra, the accumulation of Cr was not detected and may be grown in this area.  相似文献   

7.
Bio-monitoring of some heavy metal levels (Cd, Pb, Zn, Cu) in whole edible soft parts of Mytilus galloprovincialis (L. 1758) was conducted in Turkish Aegean Sea coast during the period of September 2002–August 2003 seasonally. Moreover, some physico-chemical environmental parameters, also have been analysed in the same region. The values of some physico-chemical environmental parameters in coastal waters of Turkish Aegean Sea were changed between; 9.0–27.0 C for temperature, 31.93–40.45 psu for salinity, 7.35–8.48 for pH and 4.05–9.50 mg/l for dissolved oxygen. The levels of trace elements in whole edible soft parts including interstitial fluids of Mediterranean mussels M. galloprovincialis (L. 1758), sampled from 6 different regions of Turkish Aegean Sea coast have ranged between; 0.04–0.52 μg Cd/g wet weight, 0.49–1.72 μg Pb/g w.w., 0.95–1.85 Cu/g w.w., 16.11–37.15 μg Zn/g w.w. The highest values for all trace metals (Cd, Pb, Zn, Cu) were measured in inner part of Izmir Bay (station 3) and lowest in Sigacik and Gulluk Bay (station 5, 6). Generally heavy metal levels are lower than the results in soft mussel tissues reported from Mediterranean regions.  相似文献   

8.
To estimate exposure to cadmium (Cd) and lead (Pb) through cigarette smoking, the concentrations of both metals in the blood or/and urine of smokers (20 cigarettes or more per day for 10 years or longer) and their non-smoking counterparts inhabiting an environmentally unpolluted area (Bialystok, Poland) were evaluated, as well as Cd and Pb contents in the cigarette brands (produced in Poland) smoked by the participants, including intact cigarettes, pre-smoking (tobacco, paper and filter) and post-smoking (butt, ash and smoke) cigarette components. Blood and urinary Cd concentrations in the smokers have been already reported by us to be 2–4 times higher than in the non-smokers (Galażyn-Sidorczuk et al. Polish Journal of Environmental Studies, 13 (Suppl.1):91–95, 2004). All the other measurements are the subject of the present paper. Pb concentration in the blood of the cigarette smokers (52.12 ± 15.51 μg l−1) was higher by 29% than in the non-smokers (40.42 ± 11.19 μg l−1). The mean Cd and Pb contents in the cigarettes were 0.6801 ± 0.1765 and 0.6853 ± 0.0746 μg per cigarette, respectively. Under cigarette burning, performed using a machine for self-acting burning, on average 33% of Cd and 11% of Pb present in the whole cigarette was released into the smoke. For Cd, unlike Pb, there was a high positive correlation between the metal content in cigarettes and tobacco and its release into the smoke. Moreover, the subjects smoking cigarettes containing the highest Cd amount had higher blood Cd concentration than smokers of other cigarette brands. The results give clear evidence that in the case of inhabitants of areas unpolluted with Cd and Pb habitual cigarette smoking, due to tobacco contamination, creates a serious source of chronic exposure to these metals, especially to Cd.  相似文献   

9.
Elevated levels of selenium have been found in water and aquatic biota downstream from two open-pit coal mines in the Rocky Mountain foothills of Alberta. Birds are particularly sensitive to excessive dietary selenium. However, there is relatively little information on selenium accumulation in birds' eggs on fast-flowing mountain streams. We determined levels of selenium in water samples, caddisfly larvae and eggs of American dippers (Cinclus mexicanus) nesting on the Gregg River, downstream from the mines, and on reference streams in the same general vicinity. Selenium levels (mean, 95% confidence limits) in water samples and caddisflies collected from sites near dipper nests on the Gregg River (water: 4.26, 1.90–9.56 μg L−1; caddisflies: 8.43, 7.51–9.46 μg g dry wt−1) were greater than those collected from sites near nests on reference rivers (water: 0.38, 0.21–0.71 μg L−1; caddisflies: 4.65, 4.35–4.97 μg g dry wt−1). The mean (± 1SE) selenium level in dipper eggs from the Gregg River (6.3 ± 0.2 μg g−1 dry wt) was significantly higher than it was in eggs from reference streams (4.9 ± 0.2 μg g−1 dry wt). Concentrations of selenium in eggs were significantly correlated with those in water samples (r = 0.45). The maximum selenium level in eggs from the Gregg River (9.0 μg g−1) may have been high enough to warrant concern from an ecotoxicological perspective. The American dipper can serve as a useful bioindicator of selenium contamination in mountainous, lotic ecosystems.  相似文献   

10.
In groundwater, used for drinking water supply in the greater industrial area of Thessaloniki, in Northern Greece, concentrations of total arsenic exceeded the WHO provisional guideline value and the EU maximum contaminant level (MCL) of 10 μg/L. The concentration of total arsenic was in the range between 4–130 μg/L, whereas the median value was 36 μg/L and the average concentration 46 μg/L. Nine out of the eleven wells contained total arsenic at concentration higher than 10 μg/L and it should be stressed that 6 of them contain arsenic at concentrations between 10 (new MCL) and 50 μg/L (previous MCL). The examined groundwaters were found to contain elevated concentrations of manganese and phosphate. Arsenic had a positive correlation with the pH, indicating the possible effect of pH on arsenic mobilisation. These findings emerge the problem of contamination from arsenic, since, according to the EU directive 98/83, all drinking water sources within the European Union should have achieved compliance with the new limits by 12/2003, implying that the situation requires urgent remedial action.  相似文献   

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