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1.
Arsenic bioavailability in rock, soil and water resources is notoriously hazardous. Geogenic arsenic enters the body and adversely affects many biochemical processes in animals and humans, posing risk to public health. Chelpu is located in NE Iran, where realgar, orpiment and pyrite mineralization is the source of arsenic in the macroenvironment. Using cluster random sampling strategy eight rocks, 23 soils, 12 drinking water resources, 36 human urine and hair samples and 15 adult sheep urine and wool samples in several large-scale herds in the area were randomly taken for quantification of arsenic in rock/soil/water, wool/hair/urine. Arsenic levels in rock/soil/water and wool/hair/urine were measured using inductively coupled plasma spectroscopy and atomic absorption spectrophotometry, respectively. While arsenic levels in rocks, soils and water resources hazardously ranged 9.40–25,873.3 mg kg?1, 7.10–1448.80 mg kg?1 and 12–606 μg L?1, respectively, arsenic concentrations in humans’ hair and urine and sheep’s wool and urine varied from 0.37–1.37 μg g?1 and 9–271.4 μg L?1 and 0.3–3.11 μg g?1 and 29.1–1015 μg L?1, respectively. Local sheep and human were widely sick and slightly anemic. Hematological examination of the inhabitants revealed that geogenic arsenic could harm blood cells, potentially resulting in many other hematoimmunological disorders including cancer. The findings warn widespread exposure of animals and human in this agroecologically and geopolitically important region (i.e., its proximity with Afghanistan, Pakistan and Turkmenistan) and give a clue on how arsenic could induce infectious and non-infectious diseases in highly exposed human/animals.  相似文献   

2.
The seasonal speciation of mercury (Hg) was determined in water, soil, and sediments from watersheds located in the North-West province of South Africa. The study area is known to have a long history of mining activities which also include the recovery of gold from old tailings. Both inorganic (IHg) and methyl mercury (MHg) were detected at high concentrations (up to 8480 μg IHg kg?1 and 13 μg MHg kg?1) in surface sediments during dry season. A considerable remobilization of Hg from bottom sediments was observed in water from dry to wet season as well as the migration of Hg away from pollution sources due to seasonal influences. Hg in sediments mostly has been speciated as Hg0. Enhancement of Hg methylation occurred mainly in deeper sediments at regions corresponding to the lowest redox potential, higher pH, and enrichment of IHg. Hg values in borehole waters were very high (up to 3310 ng L?1) suggesting a serious contamination of the site groundwater which needs to be addressed urgently in order to minimize further impact that affects the Vaal River and other water systems located nearby.  相似文献   

3.
A field survey of mercury pollution in environmental media and human hair samples obtained from residents living in the area surrounding the Chatian mercury mine (CMM) of southwestern China was conducted to evaluate the health risks of mercury to local residents. The results showed that mine waste, and tailings in particular, contained high levels of mercury and that the maximum mercury concentration was 88.50 μg g?1. Elevated mercury levels were also found in local surface water, paddy soil, and paddy grain, which may cause severe health problems. The mercury concentration of hair samples from the inhabitants of the CMM exceeded 1.0 μg g?1, which is the limit recommended by the US EPA. Mercury concentrations in paddy soil were positively correlated with mercury concentrations in paddy roots, stalks, and paddy grains, which suggested that paddy soil was the major source of mercury in paddy plant tissue. The average daily dose (ADD) of mercury for local adults and preschool children via oral exposure reached 0.241 and 0.624 μg kg?1 body weight per day, respectively, which is approaching or exceeds the provisional tolerable daily intake. Among the three oral exposure routes, the greatest contributor to the ADD of mercury was the ingestion of rice grain. Open-stacked mine tailings have resulted in heavy mercury contamination in the surrounding soil, and the depth of appreciable soil mercury concentrations exceeded 100 cm.  相似文献   

4.
The estimated daily intakes (EDIs) of six trace elements (Cu, Zn, Pb, Cd, Hg, and As) in vegetables (leafy vegetable, i.e., bok choy, fruit vegetables, i.e., cucumber and tomato, and other categories, i.e., mushroom, kidney bean, and potato), cereals (rice and wheat flour), and meats (pork, mutton, and beef) most commonly consumed by adult inhabitants of Qiqihar, Northeastern China, were determined to assess the health status of local people. The average EDIs of Cu, Zn, Pb, Cd, Hg, and As were with 20.77 μg (kg bw)?1 day?1 of Cu, 288 μg (kg bw)?1 day?1 of Zn, 2.01 μg (kg bw)?1 day?1 of Pb, 0.41 μg (kg bw)?1 day?1 of Cd, 0.01 μg (kg bw)?1 day?1 of Hg, and 0.52 μg (kg bw)?1 day?1 of As, respectively, which are below the daily allowance recommended by FAO/WHO. However, the maximum EDIs of Pb and Cd were 4.56 μg (kg bw)?1 day?1 and 1.68 μg (kg bw)?1 day?1, respectively, which are above the recommended levels [i.e., 3.58 μg (kg bw)?1 day?1 for Pb and 1.0 μg (kg bw)?1 day?1 for Cd] by FAO/WHO. This finding indicates that the potential health risk induced by daily ingestion of Pb and Cd for the local residents should receive a significant concern. Similarly, we detected elevated Pb and Cd concentrations, i.e., with average of 13.58 and 0.60 mg kg?1 dw, respectively, in the adult scalp hairs. Consumption of rice, potato, bok choy, and wheat flour contributed to 75 and 82% of Pb and Cd daily intake from foodstuffs. Nevertheless, human scalp hair is inappropriate biological material for determination of the nutritional status of trace elements in this region.  相似文献   

5.
The present work deals with the determination of uranium concentrations in drinking and ground water samples by laser fluorimetry and calculation of cumulative, age-dependent radiation doses to humans. The concentrations were found to be between 0.20 ± 0.03 and 64.0 ± 3.6 μg L?1, with an average of 11.1 ± 1.5 μg L?1, well within the drinking water limit of regulatory bodies. The concentrations of uranium increase with depth of water samples collection. The estimated annual ingestion dose due to the intake of uranium through drinking water for all age groups varied between 0.2 and 137 μSv a?1, with an average of 17.3 μSv a?1. The mean annual ingestion dose is 5% of the global average ingestion dose, for infants, marginally higher than for other age group. Most effective dose values were less than 20 μSv a?1.  相似文献   

6.
The effect of calcium and magnesium either singly or in combination on accumulation of cadmium and copper in Labeo rohita (rohu) and Catla catla (catla) was investigated in this study under laboratory conditions. The investigation showed that copper accumulation in rohu exposed to 0.25 mg L?1 of copper for 14 days reduced from 31.0 ± 0.4 mg kg?1 at no calcium/magnesium treatment to 3.5 ± 0.2 and 2.2 ± 0.1 mg kg?1, respectively, at 75 mg L?1 calcium or magnesium treatment. The copper level in catla exposed to 0.20 mg L?1 of copper for 14 days reduced from 5.7 ± 0.1 mg kg?1 at no calcium/magnesium treatment to 3.4 ± 0.2 and 3.3 ± 0.1 mg kg?1, respectively, at 300 mg L?1 calcium or magnesium treatment. The cadmium accumulation in rohu exposed to 0.20 mg L?1 of cadmium for 14 days reduced from 1.7 ± 0.1 mg kg?1 at no magnesium treatment to 1.4 ± 0.1 mg kg?1 at 120 mg L?1 magnesium treatment. The cadmium accumulation in catla exposed to 0.20 mg L?1 of cadmium for 14 days reduced from 0.8 ± 0.2 mg kg?1 at no magnesium treatment to 0.6 ± 0.2 mg kg?1 at 80 mg L?1 magnesium treatment. Copper and cadmium treatments also reduced some essential microelements of rohu and catla. Both the fishes restored these elements at different levels of calcium and magnesium.  相似文献   

7.
The study aimed to examine the contamination status of arsenic (As) in excavated small water bodies, commonly known as ponds – the integral part of daily life in the arsenic-affected rural areas of West Bengal, India in comparison to the unaffected areas. The ponds of the contaminated area had higher levels of As: water 2–174 µg L?1 (mean 31 ± 2 µg L?1) and sediment 1.3–37.3 mg kg?1 (mean 10.3 ± 0.4 mg kg?1), than those from the unaffected area: water 1–8 µg L?1 (mean 4 ± 0 µg L?1) and sediment 1.4–5.3 mg kg?1 (mean 3.0 ± 0.1 mg kg?1). A moderate positive correlation was observed between the water and sediment arsenic content of the ponds of the arsenic-affected region (r = 0.688, n = 277, p < 0.0001). Contaminated ground water, either as direct input or through agricultural washings, was found to be the major contributor of arsenic pollution to these ecosystems. Seasonal variations were not prominent. This study emphasized the beneficial role of using the studied ecosystems over the highly contaminated ground water for various livelihood activities in the Gangetic delta region.  相似文献   

8.
A cloud-point extraction (CPE) process using the nonionic surfactant, polyethylene glycol tert octylphenyl ether (Triton X-114) was employed for determination of Hg(II) ions in aqueous solutions. The method is based on the ion-pairing reaction of Hg(II) with Pyronin B (PyrB+) in the presence of excess iodide at pH 6.0 and extraction of the complex formed. The chemical variables affecting CPE efficiency were studied, and the analytical characteristics of the method were obtained. The calibration curves were linear in the range of 1–40 μg L?1 with the detection limits of 0.35 and 0.30 μg L?1 at 556 and 521 nm. Selectivity was also tested. The coefficients of variation of the method are 2.4% and 5.2% for five replicate measurements of mercury at levels of 10 and 25 μg L?1, respectively. The results obtained for two certified reference samples were in a good agreement with the certified values. The method was applied to the determination of total mercury in vegetable samples.  相似文献   

9.
Total mercury (Hg) levels in the intertidal surface sediments along the west coast of Peninsular Malaysia were analysed by using heat vaporization method. Total Hg levels in these sediments ranged from 3.00 to 201?µg?kg?1 dry weight with a mean concentration of 60.0?µg?kg?1 dry weight. More than 90% of the samples studied have the total Hg concentrations less than 150?µg?kg?1 dry weight. Compare with the regional data and sediment quality guidelines, the Hg contamination in the intertidal area along the west coast of Peninsular Malaysia was not serious, except for a few sites that might have received anthropogenic Hg in the samples collected between 1999 and 2000. It is suggested that a similar study of heavy metals in the sediments of the west coast of Peninsular Malaysia be conducted regularly.  相似文献   

10.
Metal concentrations in sediment and in whole tissue of the benthic polychaete Glycera longipinnis collected along the southwest coast of India were analysed. Relative seasonal accumulation of metals (Cu, Pb, Cr, Ni, Zn, Cd, Hg) was studied by categorising the habitat as less polluted or highly polluted based on metal contamination routed through industrial and urban sources. The metal content in tissues varied seasonally in the ranges, Cu: 2.21–27.08 μg·g?1, Pb: 0.06–4.92 μg·g?1, Cr: 1.73–29.20 μg·g?1, Ni: 1.60–4.61 μg·g?1, Zn: 14.72–82.30 μg·g?1, Cd: 0.04–1.38 μg·g?1and Hg: below decetable limits to 0.86 μg·g?1. Concentration of heavy metals was found to be high in the whole body of G. longipinnis pooled from the polluted transects. The results of this study suggest that G. longipinnis may act as a useful biological indicator for heavy metal pollution along the southwest coast of India.  相似文献   

11.
Due to its potential toxic properties, metal mobilization is of major concern in areas surrounding Pb–Zn mines. In the present study, metal contents and toxicity of soils, aqueous extracts from soils and mine drainage waters from an abandoned F–Ba–Pb–Zn mining area in Osor (Girona, NE Spain) were evaluated through chemical extractions and ecotoxicity bioassays. Toxicity assessment in the terrestrial compartment included lethal and sublethal endpoints on earthworms Eisenia fetida, arthropods Folsomia candida and several plant species, whereas aquatic tests involved bacteria Vibrio fischeri, microalgae Raphidocelis subcapitata and crustaceans Daphnia magna. Total concentrations of Ba (250–5110 mg kg?1), Pb (940 to >5000 mg kg?1) and Zn (2370–11,300 mg kg?1) in soils exceeded intervention values to protect human health. Risks for the aquatic compartment were identified in the release of drainage waters and in the potential leaching and runoff of metals from contaminated soils, with Cd (1.98–9.15 µg L?1), Pb (2.11–326 µg L?1) and Zn (280–2900 µg L?1) concentrations in filtered water samples surpassing US EPA Water Quality Criteria (2016a, b). Terrestrial ecotoxicity tests were in accordance with metal quantifications and identified the most polluted soil as the most toxic. Avoidance and reproduction tests with earthworms showed the highest sensitivity to metal contamination. Aquatic bioassays performed in aqueous extracts from soils confirmed the results from terrestrial tests and also detected toxic effects caused by the mine drainage waters. Algal growth inhibition was the most sensitive aquatic endpoint. In view of the results, the application of a containment or remediative procedure in the area is encouraged.  相似文献   

12.
Mercury (Hg) is a potent nephrotoxin. The aim of this study was to investigate the protective role of Curcuma longa extract and curcumin against HgCl2-induced nephrotoxicity. Male Sprague Dawley rats were administered HgCl2 (12 μmol kg?1, ip; once only) followed by treatment of Curcuma longa extract (200 mg kg?1, po) and curcumin (80 mg kg?1, po) for three days after 24 h of HgCl2 administration. The present results showed that mercuric chloride administration caused an impairment of renal function system which was evident from significant increase in urea, creatinine, uric acid, and blood urea nitrogen concentration in serum. In addition, the swelling in glomerulus and degenerated renal tubules with obstructed lumen was also observed by acute mercuric chloride administration. Treatment with Curcuma longa extract and curcumin was effective in restoring all variables of kidney functions near to control group, which was consistent with kidney histoarchitecture. In conclusion, these results suggest that Curcuma longa extract and curcumin protect against HgCl2-induced nephrotoxicity. This study could be important for the further understanding of mercury toxicity in renal tissues and in the development of better treatments for people and/or animals exposed to the metal.  相似文献   

13.
In the present work, determination of ultratrace amounts of thallium in water samples was performed by ultrasound-assisted emulsification microextraction based on solidification of a floating organic drop as sample preparation method prior to furnace atomic absorption spectrometry. 1-(2-Pyridylazo)-2-naphthol was used as chelating agent. The factors influencing the complex formation and extraction, such as pH of the aqueous solution, the type and the volume of extraction solvent, the volume of chelating agent solution, and the extraction time were investigated. Under optimized conditions, the enrichment factor was 200. The calibration graph was linear from 0.2 to 10.0 μg L?1 with a correlation coefficient of 0.9966, the detection limit was 0.03 μg L?1 and reproducibility was ±3.3% (C = 5.0 μg L?1, n = 8). The method was successfully applied for the determination of thallium in water samples.  相似文献   

14.
A simple and efficient ionic liquid-based ligandless microextraction method has been developed for preconcentration of cadmium ions (Cd2+) as a step prior to its determination by flame atomic absorption spectrometry (FAAS) with a micro-sample introduction system. In this approach, the ionic liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate [C4mim][PF6] and ethanol were used as extractant and dispersive solvents to preconcentrate the Cd2+ in different waters, acid digested scalp hair, and nail samples. Some analytical parameters influencing the extraction efficiency of Cd2+ and its subsequent determination, including pH, IL volume, dispersant solvent volume, sample volume, temperature, incubation time, and matrix effect, were optimized. Under optimal conditions, the limit of detection (LOD), limit of quantification (LOQ), and enhancement factor (EF) were 0.4 μg L?1, 1.3 μg L?1, and 50, respectively. The relative standard deviation (RSD) of 100 μgL?1 Cd2+ was 4.3% (n = 6). The validity of the proposed method was checked by determining Cd2+ in certified reference material (TM-25.3 fortified water) and standard addition; the results showed sufficient recovery (>98%) of Cd2+ within the certified value. The method was applied for preconcentration and determination of cadmium in waters and biological samples.  相似文献   

15.
Cleaning validation is a major challenge in multi-product pharmaceutical industries. UV spectrophotometric and HPLC methods have been developed and validated for determination of residual amount of Loratadine. Both methods were validated for linearity, range, accuracy, precision, and robustness. The limit of quantification was 1 mg L?1 by UV spectrophotometric method and 0.5 mg L?1 by HPLC method. A spike recovery study was done on a stainless steel (316 grade) plate and specific residual cleaning level (SRCL) was down to 6 μg 25.8 cm?2. Recovery was found to be more than 70%. Both methods were simple, highly sensitive, precise, and accurate, and have potential of being useful for routine quality control.  相似文献   

16.
Catecholamines and their metabolites affect children's nervous system. Dopamine is an important neurotransmitter in the brain. In the routine analysis for diagnostics of diseases, the dopamine metabolite homovanillic acid (HVA) is determined. Mercury is a neurotoxic agent and can cause different undesirable effects on the brain. In the present work a putative correlation between HVA, the main metabolite of dopamine, and mercury in urine of healthy and autistic children was studied. The level of HVA was higher in the urine of autistic children (14.5 ± 8.3 mg L?1) compared to generally healthy children (4.4 ± 0.5 mg L?1). The level of mercury in the urine of autistic children was lower (0.36 ± 0.24 µg L?1) than in the urine of healthy children (2.1 ± 1.0 µg L?1) showing that there is no correlation between HVA and mercury.  相似文献   

17.
Sediment samples were collected from Tinishu Akaki River (TAR), Lake Awassa, and Lake Ziway, Ethiopia for determination of mercury. The air-dried samples were analyzed for mercury with a differential atomic absorption spectrometer after thermal evaporation of bound mercury converting it to its atomic form. Certified reference materials (CRMs) of sediments and soils were used to validate the method. The recovery of mercury from CRMs and sediments was in the range of 95–100%. The limit of detection for the determination of mercury was 50?ng?kg?1. The concentration of total mercury in the sediments varied from 3.9 to 110?µg?kg?1 for TAR, 14 to 67?µg?kg?1 for Lake Awassa, and 17 to 110?µg?kg?1 for Lake Ziway. It was found that the total mercury concentrations in all samples were below the United States Environmental Protection Agency guideline of 200?µg?kg?1.  相似文献   

18.
Mercury and arsenic pollution has been recognized as a potential environmental and public health problem for over 40 years. The major source of exposure to mercury for humans is the ingestion of fish. This study was conducted with the aim of determining the levels of mercury and arsenic in the muscles of four fish species caught in the Beheshtabad River and comparing the results with the maximum tolerance levels for mercury and arsenic. The samples of 90 fish were used for the determination of both the metals by graphite furnace atomic absorption spectrometry. The results showed that the concentrations ranged from 1.5 to 3.8 µg kg?1 for mercury and from 35 to 70 µg kg?1 for arsenic, with means of 2.7 ± 0.5 and 57 ± 12 µg kg?1, respectively. Both mean levels were lower than the threshold limits acceptable by WHO standards.  相似文献   

19.
Controlled laboratory experiments were conducted to examine how photosynthesis and growth occur in Potamogeton wrightii Morong under different photoperiods and nutrient conditions. The experiment was based on a 3×2 factorial design with three photoperiods (16, 12 and 8 h) of 200 μE · m?2·s?1 irradiance and two nutrient conditions, high (90 μmol N · L?1·d?1 and 9 μmol P · L?1·d?1) and low (30 μmol N L?1·d?1 and 3 μmol P · L?1·d?1). After 14, 28, 56 and 70 days of growth, plants were harvested to determine net photosynthesis rate and various growth parameters. Above- and below-ground biomass were investigated on days 56 and 70 only. Plants under low nutrient conditions had greater leaf area, more chlorophyll a, a higher rate of net photosynthesis and accumulated more above- and below-ground biomass than plants in the high nutrient condition. Plants with an 8 h photoperiod in the low nutrient condition had a significantly higher rate of net photosynthesis, whereas 8 h photoperiod plants in the high nutrient condition had a lower rate of net photosynthesis and their photosynthetic capacity collapsed on day 70. We conclude that P. wrightii has the photosynthetic plasticity to overcome the effects of a shorter photoperiod under a tolerable nutrient state.  相似文献   

20.
The rapid decline of the wild Milky Stork population in Malaysia has led to the reintroduction of the captive bred species in Kuala Gula, Perak. The area is known as an important migratory stopover and sanctuary for both visitors and resident birds. Although Kuala Gula and its adjacent areas are regarded as pristine and unpolluted, recent study suggested that accumulation of certain pollutants is occurring in the aquatic environment of the area. Surface sediment samples from five foraging areas considered important to the reintroduced Milky Storks have been analyzed for metals contamination. The results show that elevations of Cu, Zn, and Pb ranging from 9.7 to 57 mg kg?1, 71 to 120 mg kg?1, and 28 to 47 mg kg?1 have occurred, except for Cd (0.9–1.7 mg kg?1). The accumulation of these metals is site-specific which reflects continuous anthropogenic inputs into the aquatic environment of Kuala Gula. In addition, metal levels in some areas have exceeded the effects range low values, and thus urgent action is needed to ensure good practice and sustainable management of Kuala Gula by responsible parties.  相似文献   

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