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1.
In the context of use of marine algae as biological indicators of heavy metal pollution in coastal waters, six species of marine algae collected from the southwest coast of India were analysed for the levels of heavy metals (Ni, Cr, Sr, and Ag). Interspecies and interclass variations were determined on a spatial and temporal scale. The metal contents varied in the ranges, Ni: 0.20–21.06?µg?g?1 (mean?=?10.13?µg?g?1), Cr: non-detectable level (ND)–37.18?µg?g?1 (mean?=?13.86?µg?g?1), Sr: 2.19–103.90?µg?g?1 (mean =?29.40?µg?g?1), and Ag: ND–6.39?µg?g?1 (mean?=?1.80?µg?g?1). Ni and Cr contents were of similar magnitude to those reported for algae from polluted areas.  相似文献   

2.
In this study, we present evidence of lead in lip liner, oil absorbent powder, mascara, concealer, lipsticks, lip gloss, and foundation. The samples were analyzed for lead by flame atomic absorption spectrometry. The levels of lead in concealer, mascara, lip liner, and oil absorbent powder were found to be 7.4?±?1.3?µg?g?1, 15.8?±?0.2?µg?g?1, 29.0?±?9.2?µg?g?1, and 17.3?±?2.9?µg?g?1, respectively. The levels of lead in lipsticks, lip gloss, and foundation ranged from not detected to 73.1?±?5.2?µg?g?1, 4.7 to 11.7?±?2.8?µg?g?1, and 7.8 to 32.9?±?1.4?µg?g?1, respectively. Thus, in the majority of samples, the concentrations of lead are higher than the USFDA maximum permissible concentration of 0.10?µg?g?1 in candy and cosmetics. In lipsticks alone, only 25% of 40 samples were found to meet the requirement. Therefore, continuous use of cosmetic products in which lead concentration exceeds the maximum permissible level may pose a health hazard for the female population of South Africa in the long run.  相似文献   

3.
This study was aimed to evaluate the comparative distribution, correlation and apportionment of selected elements (Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Pb and Zn) in the scalp hair of arthritis patients and healthy subjects. The hair samples collected from the patients (rheumatoid and osteoarthritis) and healthy donors were digested in nitric acid and perchloric acid mixture, followed by the quantification of trace elements using atomic absorption spectrometry. In the case of healthy donors, highest mean concentration was shown by Ca (3240?µg?g?1), followed by Mg (340?µg?g?1), Zn (192?µg?g?1), Fe (184?µg?g?1) and Pb (27?µg?g?1), whereas, the estimated average metal levels in rheumatoid arthritis and osteoarthritis patients were 3160, 290, 197, 61 and 23?µg?g?1, and 3090, 300, 182, 50 and 21?µg?g?1, respectively. Most of the elements revealed diverse and random distribution in the scalp hair of the donor groups. The correlation study pointed out significant disparities in the mutual relationships among the trace elements in the patients and controls. Principal component analysis and cluster analysis of the element data manifested diverse apportionment of the selected elements in the scalp hair of the patients compared with the healthy counterparts.  相似文献   

4.
Fish is the main food in coastal areas and its analysis for toxic metals has been used as an indicator of the pollution status of the aquatic environment. Several different fish species from the three Indian coasts, Visakhapatnam in the east, Mumbai in the west and Mangalore in the south west and also inland freshwater fish from Nagpur in the central region for comparison were analyzed for up to 20 elements (As, Au, Ba, Br, Cl, Co, Cr, Cu, Fe, Hg, K, Mn, Na, P, Rb, Sb, Sc, Se, Sr, Zn) by instrumental neutron activation analysis (INAA). Dried fish samples in powdered form were irradiated with thermal neutrons in a nuclear reactor followed by high resolution gamma ray spectrometry at different intervals. Several Reference Materials (RMs) of biological origin were analyzed for quality assurance and data validation. Elemental contents in different fish species vary in a wide range depending on the species, its size, location, and aquatic environment. Fish from Mangalore showed highest mean contents of Cr (14.8?±?29.9?µg?g?1), Cu (1005?±?643?µg?g?1) and Sb (849?±?888?ng?g?1) whereas those from Mumbai exhibited highest Hg (2066?±?2146?ng?g?1) and P (20.3?±?4.63?µg?g?1) but lowest Cu (6.30?±?3.10?µg?g?1) contents. Fish from all the regions showed significant amounts of nutrient elements such as Na, K, P, Mn, Fe, Se and Zn as well as some pollutant elements (Br, Cr, Sb, Hg). No regularity in variation of elemental contents with the size was observed. Prawn (Panaeus latisulcatus), a popular fish species from four different regions showed wide variation in elemental contents of Cr, Mn, Fe, Zn, Se, P including toxic pollutants, Sb and Hg. An attempt has been made to calculate daily dietary intake (DDI) for some nutrient elements from Indian fish. Elemental data for Cr, Cu, Fe, Hg, Se, and Zn have been compared with those from other fish exporting countries.  相似文献   

5.
We investigated the leaching characteristics of bisphenol A (BPA) from two kinds of epoxy-resin pavement materials, one containing epoxy resins (EPs) and the other containing epoxy-acrylate resins (EPAs). Both samples contained residual BPA monomer, at levels of 9.0?µg?g?1 for the EP resin sample and 4.4?µg?g?1 for the EPA resin sample. These amounts were larger than amounts previously measured for polycarbonate samples. The amount of BPA leached from the samples increased with temperature. The leaching of BPA from EP was more strongly affected by temperature than the leaching from EPA. The pH also affected the amount of leached BPA. The maximum leached amount was observed under alkaline conditions (pH 10.8) for both sample types. The amounts of BPA that might leach from pavement materials during 1?h of heavy rain were estimated to be 0.9?µg?m?2 for EP and 3.5?µg?m?2 for EPA. Our results indicate that EPs disposed of in waste landfills without any treatment may be a source of BPA in leachate at landfill sites.  相似文献   

6.
Arsenic (As) contamination of the available domestic drinking water from shallow aquifers to villagers in Bangladesh often exceeds the newest WHO standard of <10 µg As L?1 and the older Bangladeshi standard of <50 µg As L?1. An estimated 9.2 million shallow tube wells in Bangladesh deliver water to 97% of the rural population, placing an estimated 57 million people at risk for arsenicosis. The contamination of drinking water by As extends to W. Bengal, India and Nepal. The same shallow aquifers used for domestic water are also used to irrigate food crops, particularly rice. Irrigation adds As to soils and increases exposure of the population to additional As via foods consumed. Selenium (Se), an essential trace mineral found in soils, is absorbed by plants, entering the human food chain. It was suggested that a low dietary intake of Se may be contributing to the problem of human arsenicosis in Bangladesh. Dietary Se acts as a natural antidote to As by (1) accelerating As excretion, (2) sequestering As by complexation and (3) as an antioxidant component of the enzyme glutathione peroxidase that may counteract the prooxidant effects of As that contribute to arsenicosis and cancer. Analysis of 70 agricultural soil samples from Bangladesh by fluorimetry, ICP-AES and Neutron Activation Analysis showed the soils analyzed to be high in As (~33 µg g?1) and biologically low in soluble Se (~0.02 µg g?1). A low dietary intake of Se related to low soil content and this mineral in foods may be contributing to human arsenicosis in the Ganges–Brahmaputra delta.  相似文献   

7.
Food is the major source of metal exposure for the nonsmoking general population. Food samples of plant and animal origin from Ismailia, Egypt, were analyzed for the content of cadmium (Cd), lead (Pb), chromium (Cr), zinc (Zn), and copper (Cu) using AAS. The Cr, Zn, and Cu concentrations were in the range of 1.7–249?µg?kg?1 wet weight (ww), 2–66?mg?kg?1?ww, and 0.5–3.46?mg?kg?1?ww, respectively. The mean daily intake of Cr, Zn, and Cu was 28.9?µg day?1, 8.55?mg day?1, and 1.7?mg day?1, respectively. The intake estimates are within the range of the recommended intake established internationally. Concentrations of Cd and Pb were in the range of 10–321?µg?kg?1?ww and 31–1200?µg?kg?1?ww, respectively. The weekly dietary intake for Cd and Pb (4.02 and 20.4?µg?kg?1 b.w, respectively) is lower than the FAO/WHO PTWI. Bread is the foodstuff that provided the highest rate of Pb and Cd (62 and 46% of the daily intake) to adults in Ismailia city.  相似文献   

8.
Seven species of marine fish in the Persian Gulf and three species of marine fish in the Caspian Sea were collected from the local wholesale market in Mashhad, Iran. The mercury (Hg) concentration in muscle samples was determined by atomic absorption spectrophotometry. High total Hg concentration was found in Anchovy sprat (2.04 ± 1.23 µg g?1) and Whitecheek shark (1.26 ± 1.85 µg g?1) and the lowest content was detected in common carp (0.24 ± 0.24 µg g?1) and Caspian salmon (0.25 ± 0.08 µg g?1). The mean Hg content in all samples was 0.91 ± 1.07 µg g?1. All samples of Persian Gulf and one sample of Caspian Sea had mean Hg concentration above 0.5 µg g?1, the level established by joint FAO/WHO on Food Additives. Results showed that the estimated weekly intake of total Hg by a 60 kg adult is below the provisional tolerable weekly intakes recommended by joint FAO/WHO on Food Additives. For prevention of health risks, populations in Iran need to consume fish in moderate amounts.  相似文献   

9.
Long-finned pilot whales (Globicephala melas) from the Faroe Islands are known to be heavily polluted with contaminants, such as mercury (Hg) and organochlorine compounds (OC). This is postulated to exert adverse health effects on whales as well as the human population who rely on its meat and blubber as food sources. It was therefore decided to conduct a screening pilot study to determine contaminant concentrations and histopathology of liver and renal tissues in a total of 14 specimens from this subpopulation. In blubber, the mean ∑OC concentration was 31,887 ng g?1 lw (range: 18,170–47,425 ng g?1 lw) of which ∑PCB concentration was 23,416 ng g?1 lw (range: 13,947–34,543 ng g?1 lw; n = 3). In liver, mean Hg concentration was 138 µg?1 ww (range: 54–351 µg g?1 ww; n = 7) and mean cadmium (Cd) concentration 15 µg g?1 ww (range: 7–31 µg g?1 ww; n = 7). In the kidney, the mean Cd concentration was 36 µg g?1 ww (range: 23–47 µg g?1 ww; n = 7). Of the liver Hg concentrations, two were at the suggested toxic threshold levels of 60 µg g?1 ww and five were 2–6-fold above. Liver selenium (Se) : Hg was on average 1.11 (range: 0.97–1.41; n = 7) indicating that Se was in excess, which decreased the risk of acute Hg poisoning. Histopathological examinations showed high prevalence (>35%) of renal glomerular arteriosclerosis, glomerular capillary dilatation, dilatation and hyalinization of Bowman's space/capsule and tubular hyaline casts. In liver tissue, high prevalence was found for portal cell infiltrates, lipid granulomas, hepatocytic lipid accumulation, bile duct proliferation, lipid-filled Ito cells, and focal necrosis. In a single juvenile male, 4 of 8 renal and 3 of 7 liver lesions were present. Cadmium concentrations increased significantly in the presence of glomerular arteriosclerosis and a similar trend was found for tubular hyaline casts. Based on these findings, as well as the nature of the lesions, data indicate that the histopathological changes were a result of age and that contaminants are likely to be the co-factors in the development in at least three renal and four liver lesions.  相似文献   

10.
Bisphenol A (BPA), the plastic monomer and plasticizer with well-known endocrine-disrupting chemical properties, is widely present in the aquatic environment, but little is known regarding hepatic toxicity in fish. This study assessed the effects of chronic exposure to BPA on the antioxidant defense system of Japanese medaka liver. Fish were exposed to sub-lethal concentrations of BPA (0.1, 1, 10, 100, or 1000?µg?L?1) for 60 days. Antioxidant parameters were determined and compared with controls. The results showed that the activities of catalase (CAT), superoxide dismutase, glutathione peroxidase, glutathione S-transferase, and the content of reduced glutathione were all induced at 10?µg?L?1 BPA after 60 days. Further, hepatic CAT was sensitive to BPA at 1?µg?L?1 concentration. In conclusion, CAT may serve as a potential early biomarker of BPA exposure in aquatic environment.  相似文献   

11.
This study aims to determine heavy-metal levels in soil from the banks of Lake Nasser, the ability of Tamarix nilotica to accumulate such metals from soil and hence its potential for phytoextraction. Soil and Tamarix samples were collected from the banks of four bights around Lake Nasser and analysed for Fe, Mn, Ca, Mg, Cr, Cu, Ni, Zn, Cd and Pb by atomic absorption spectrometry, whereas Na and K were measured by atomic emission spectrophotometry. Three different methods of extraction were used for the soil samples. Lead, copper and zinc were equally distributed between the exchangeable phase and Fe/Mn oxide-bound form, while other measured metals were mainly present in the Fe/Mn oxide fraction. With the exception of iron, all metals studied showed total concentrations within the geochemical background values. T. nilotica exhibited elevated concentrations of Na (36.2–48.5?mg?g?1) and K (2.74–4.33?mg?g?1) in stems, and relatively high concentrations of Pb, Cd and Co (0.39–1.03?µg?g?1, 0.24–1.3?µg?g?1 and 1.94–5.3?µg?g?1, respectively) are found in plant leaves. Bioaccumulation factors of Na and K (9.3 and 12.63, respectively) were high in T. nilotica stems. While the bioaccumulation of Pb, Cd, Co and Ni (2870.1, 2035.4, 10.5 and 5313.2, respectively) was high in plant leaves, Fe, Mn, Ca and Mg were accumulated relatively equally in plant stems and leaves. T. nilotica was found to secrete high amounts of Na, Ca and K, in addition to small amounts of all accumulated metals except Cd and Cu. These secreted metals appeared as salt crystals (67.5% Na; 25.8% Ca; 5% Mg; 1.5% K and 0.16% trace and minor elements) on the plant surface. The concentrations of all the metals studied in T. nilotica were higher than in the salt crystals. Statistical analysis of the database suggests bioaccumulation of these metals from soil to T. nilotica. This reflects the importance of using T. nilotica as a model in the phytoremediation process as an established environmental clean-up technology.  相似文献   

12.
Ozone reduction enhances the amount of ultraviolet (UV) radiation reaching the aquatic ecosystems, which can induce adverse effects on fish. In order to study the UV radiation effects on skin structure and ultrastructure, the alevins of Salmo trutta caspius were exposed to two different doses of UV radiation (low doses of: 60 µW cm?2 UVC; 100 µW cm?2 UVB; and 40 µW cm?2 UVA and high doses of: 90 µW cm?2 UVC; 130 µW cm?2 UVB; and 50 µW cm?2 UVA) for 15 min once a day in dark condition. Alevins with no exposure to either solar light or UV exposure served as the control group. No mortality was observed in the control group, whereas all of the alevins died in the 9th day in both UV exposure groups. Light microscopic and scanning electron microscopic studies showed significant reduction in the epidermis thickness, number of skin mucous cells, and percentage of mucus secreting cells in both UV exposure groups. Sunburn cells, lifting epidermis from basal membrane, and disappearance of pavement cell microridges were also observed. Our results showed that UV radiation caused intensive skin cell lesions in the Caspian salmon alevins. Since the skin cells of trout alevins possesses essential roles in respiration, osmoregulation, excretion and defense, the observed damages to the skin could be attributed to their sudden mortality in the UV exposure.  相似文献   

13.
In this study, residual concentrations of chlorpyrifos (CPF) were determined in feed (40) and fodder (25) samples collected from various locations of Tarai region of Uttarakhand. For extracting residues, liquid–liquid partition followed by alumina column clean up was used and the detection and quantification of residues was undertaken with the help of high-performance liquid chromatography using C18 column and diode array detector at 220?nm. Of the total 40 feed samples analyzed, 7 (17.5%) samples were found positive for CPF with the mean residual concentration of 0.058?µg?g?1; while out of 25 fodder samples, CPF residues were detected in a single (4%) sample with residual concentration of 0.39?µg?g?1. However, none of the feed or fodder samples contained CPF residues above the prescribed limit.  相似文献   

14.
The impact of bisphenol A (BPA) on Gammarus fossarum and Lumbriculus variegatus was studied in four artificial indoor streams (0, 5, 50 and 500?µg?L?1 BPA, nominal) over 103 days in a pulse–dose exposure scenario (weekly BPA application). For G. fossarum populations at day 103, the proportions of juveniles and of breeding females from the highest BPA treatment were in tendency reduced. For individually exposed gammarid pairs an EC10 of 17?µg?L?1 BPA (nominal) for the proportion of reproductive females in the fourth brood was determined. During the first three broods, the largest brood size occurred at the highest BPA concentration, whereas in the fourth brood it decreased concentration-dependently (fourth brood EC10?=?5?µg?L?1 BPA, nominal). Effects on L. variegatus were a reduced population growth (103?d-EC10 of 2?µg?L?1 BPA, nominal) and an increase in dry weight and the number of segments in large, complete worms.  相似文献   

15.
It is well known that lead (Pb) produces reduced haemoglobin (Hb) levels and risk of anemia when blood lead levels (BPb) are greater than 20?µg?dL?1. Two recent studies reported an increased risk of anemia in children with BPb between 10–20?µg?dL?1, but few studies examined the association between Hb levels or risk of anemia and BPb under 10?µg?dL?1. In the present study this association was examined using data of 140 preschool children from a larger prospective cohort study in China. Data showed that compared to children with BPb <5?µg?dL?1, children with BPb between 7.5–10?µg?dL?1 had significantly lower Hb levels, but there were no marked differences for other groups. A linear regression model showed a negative relationship between BPb and Hb levels after controlling for age, gender, height, weight, and iron (Fe) deficiency. This finding, although limited by a small sample size, suggests it may be important to examine Pb-induced hemosynthesis effect at concentrations less than 10?µg?dL?1.  相似文献   

16.
The potentials of tropical weeds namely, Nephrolepis biserrata, Panicum maximum, Eleusine indica, and Chromolaena odorata to accumulate lead (Pb) and cadmium (Cd) from soil within the premises of an automobile battery manufacturing company in Ota, south-western Nigeria, were explored. The weed samples were collected in both wet and dry seasons. Standard analytical methods were employed to collect, digest, and analyze the weeds. Lead levels in the weeds for both seasons ranged from 1990–4870, 1090–1730, 4800–7890, and 400–1210 µg g?1 dry weight (DW) for Nephrolepis biserata, Panicum maximum, Eleusine indica, and Chromolaena odorata, respectively, while the cadmium level in the weeds for both seasons ranged from 3.92–6.78 µg g?1 DW for N. biserata, 1.99–6.85 µg g?1 DW for P. maximum, 2.90–7.40 µg g?1 DW for E. indica, and 2.90–5.09 µg g?1 DW for C. odorata. There was no significant difference in the accumulation of both Pb and Cd for the two seasons. All the weeds showed Pb levels higher than the phytotoxic range. On the contrary, 99% of the weeds showed Cd concentration within the phytotoxic range. The weeds demonstrate good phytoremediation potentials of contaminated soil.  相似文献   

17.
Metal contents of waste mobile phones represent a major environmental risk, especially considering the adoption of inappropriate management options in developing countries including open burning and disposal into surface water bodies. In this study the metal contents of mobile phone printed wiring board (PWB) samples were assessed. Sixty-two waste mobile phones of 15 brands were collected, dismantled, and their PWB samples were analyzed for Cu, Pb, Ag and Cd. The metal concentrations in the samples varied widely between and within brands. Among these metals, Cu and Pb were found to be at very high concentrations. The range (mean?±?SD) of Cu and Pb concentrations were 94.1–532?g?kg?1 (250?±?92.3?g?kg?1) and 7.0–46.2?g?kg?1 (20.1?±?8.4?g?kg?1), respectively. All Cu and Pb concentrations exceeded toxicity threshold limit concentration (TTLC) regulatory limits used in characterizing wastes as hazardous in the state of California, USA. The mean Cu and Pb concentrations exceeded the corresponding TTLC limits by factors of 100 and 20, respectively. The Ag and Cd concentrations were in the range 59.4–759?mg?kg?1 (mean 227?±?104?mg?kg?1) and ND – 15.6?mg?kg?1 (2.1?±?3.3?mg?kg?1), respectively.  相似文献   

18.
The levels of water soluble and total fluoride concentration in 11 different varieties of Ethiopian khat (Catha edulis Forsk, an evergreen stimulant plant) commonly consumed in the country and exported to the neighboring countries were determined by fluoride ion-selective electrode. Known amounts of fresh khat samples were suspended in deionized water, stirred, and the supernatants exposed to a chelator that decomplexes fluoride were assayed. The total fluoride concentration in the leaves was also analyzed after the leaves were dried, charred, and ashed. Water soluble and total fluoride concentration in khat varieties varied, ranging from 0.19 to 0.43 µg g?1 fresh weight and 3.4 to 7.1 µg g?1 dry weight, respectively. The fluoride concentration in matured leaves (12 µg g?1) was higher than that in young leaves (6.5 µg g?1) dry weight. Assuming that daily khat leaves chewing for an adult is 100 g, fluoride intake from chewing leaves of the analyzed khat varieties is far below the daily fluoride tolerable upper limit. The safe intake of fluoride is recommended to be 1.5–4.0 mg day?1 for adults and less for children. However, chewing khat leaves may contribute a significant amount of fluoride for the total daily intake of an individual and should not be overlooked while estimating the total dietary intake of fluoride for individuals chewing khat leaves regularly.  相似文献   

19.
The objective of this study was to determine the blood lead level (BLL) of children aged under 5 living in western Uttar Pradesh, India. A total of 100 blood samples, 100 drinking water samples, and 21 vegetable samples were assessed for lead (Pb) contamination. BLL was observed in the range of 3–11.58?µg?dL?1 with a maximal level of 11.58?±?0.05?µg?dL?1 in Kazipur village. Lead in water samples was detected in the range of 0.006–0.095?ppm and identified at upto 9.5-fold higher than the stated permissible limit. A significant positive correlation (+0.679) was obtained between BLL and water Pb levels. All vegetable samples were also contaminated with Pb upto 12-fold higher than the permissible limit of 2.5?µg?g?1 of Prevention of Food Adulteration Act (PFA) 1954. Untreated industrial effluents were identified as the responsible factors for Pb occurrence in the study area. The presence of lead may be associated with the increased antisocial activities of children living in western Uttar Pradesh. Children with elevated BLL had poorer nutritional status than those with background Pb levels. There is an urgent need for a national campaign to monitor the BLL of children in India.  相似文献   

20.
Life-long strontium patterns in otoliths of the sciaenid Micropogonias furnieri caught in the southwestern Atlantic Ocean were examined to evaluate estuarine dependency and habitat use. Otolith Sr concentrations were on average 820?±?55?μg?g?1 for freshwater, 1,751?±?101?μg?g?1 for estuarine, and ranged from 2,000 to over 4,000?μg?g?1 for marine waters. The examination of life-long otolith Sr revealed that 71?% of the marine-sampled fish moved toward brackish waters from age 0 to age 1, and that estuarine egress ranged from ages 2.1 to 4.1?years depending on the sampling area. Three different long-term patterns of Sr accumulation were observed and inferred to be the result of ontogeny and habitat shifts. Given that an estuarine Sr signature was consistently present in all sampled fish, M. furnieri is suggested to be a true estuarine-dependent species during its early life history.  相似文献   

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