Screening of thyroid gland histology in organohalogen-contaminated glaucous gulls (Larus hyperboreus) from the Norwegian Arctic

The associations between blood organohalogen contaminant (OHC) concentrations and thyroid gland histology were studied in 10 adult female glaucous gulls (Larus hyperboreus) from the Norwegian Arctic (Bjørnøya) during the incubation period. This histological investigation was undertaken as previous glaucous gull studies from the same area reported negative relationships between circulating OHC concentrations and thyroid hormone levels. Organohalogen concentrations have previously been associated with altered blood plasma thyroid hormone concentrations, as a result of parenchymal thyroid gland alterations and perturbation of the hypothalamic-pituitary-thyroid (HPT)-axis. In this study, PCB (range: 186–1027 ng g^?1ww), DDT (77–203 ng g^?1ww) and chlordane (18–65 ng g^?1ww) concentrations dominated the blood plasma OHC profile in incubating female glaucous gulls. High density of small follicles accompanied by follicular epithelial cell proliferations was seen in thyroid glands in seven of 10 gulls. Focal thyroiditis and nodular hyperplasia were found in two birds. No significant differences in plasma OHC concentrations were noted between gulls exhibiting high density of small follicles and cell proliferations and those birds not showing histological changes. Based on these findings, data suggest that the histological changes in thyroid glands of OHC-contaminated female glaucous gulls may be due to natural variance, although an OHC-induced thyroid stimulating hormone (TSH) perturbation resulting in epithelial cell hyperplasia and increased follicular density cannot be ruled out and remains to be verified. Hence, a large-scale histological study is required, in order to elaborate the potential linkage between changes in thyroid gland histology, OHC exposure and regulation of the HPT-axis in the Arctic-breeding glaucous gull.     

Liver and renal histopathology of North Atlantic long-finned pilot whales (Globicephala melas) contaminated with heavy metals and organochlorine compounds

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.     

Monitoring and risk assessment of polychlorinated biphenyls (PCBs) in agricultural soil from two industrialized areas

For monitoring and risk assessment, levels and distributions of Σ₂₉ PCBs in paddy soil samples collected from Gwangyang (10 sites) and Ulsan (20 sites), heavily industrialized cities in Korea, were investigated using high-resolution gas chromatography/high-resolution mass spectrometry. Overall, total concentrations of Σ₂₉ PCBs in Gwangyang (216.4–978.6 pg g^?1 dw) and Ulsan (273.8–1824.1 pg g^?1 dw) were higher than those (106.6–222.6 pg g^?1 dw) in agricultural soil from Anseong in Korea. The TEQ (toxic equivalency) values from Gwangyang (0.06–0.40 ng TEQ kg^?1 dw) and Ulsan (0.06–0.22 ng TEQ kg^?1 dw) were higher than those (0.04–0.11 ng TEQ kg^?1 dw) in Anseong but lower than the WHO threshold level (20 ng TEQ kg^?1). However, one of the most toxic congeners, PCB 126, gave the highest concentration, possibly posing a risk to the biota. Seven indicator PCB congeners contributed to 50–80% of the total concentration of Σ₂₉ PCBs, indicating the 7 PCBs can be used as valuable indicators for monitoring. The principal component analysis and cluster analysis for the homologue profiles of PCBs indicated that all the samples from both cities had the similar PCB contamination patterns, and the major sources of the PCB contamination were most likely from the usage of Aroclor 1254 than those of Aroclors 1242 and 1260. These PCB technical mixtures were possibly significantly used by various industries including iron and steel industries in Gwangyang and petrochemical and shipbuilding industries in Ulsan.     

Organochlorine residues in maternal milk from inhabitants of the Thohoyandou area,South Africa

The presence of organochlorine compounds (OC) such as DDT and their metabolites in the environment have created a significant environmental concern over the years due to adverse effects. Consequently, DDT has been banned in many countries. However, it is still used in some countries including South Africa, particularly for vector-borne disease eradication programmes. Since the presence of DDT and its metabolites may provide an indication of the general exposure and use of these compounds, there was a need for such a study. Human breast milk samples (n = 30) were collected from mothers within the age range of 19–40 years from the Thohoyandou area, South Africa. The liquid–liquid extraction method was used to extract DDT and its metabolites from the samples. The crude extracts were subjected to column chromatography for measurements of OC levels. The concentration ranges of the contaminants were as follows: not detected (ND) to1770 ng g^?1 (2,4′-DDE); ND to 3977 ng g^?1 (4,4′-DDE); ND to 3250 ng g^?1 (2,4′-DDD); ND to 2580 ng g^?1 (4,4′-DDD) and ND to 2847 ng g^?1 (4,4′-DDT). The mean ΣDDE, ΣDDD and ΣDDT obtained from the villages were 1180 ng g^?1, 830 ng g^?1 and 690 ng g^?1, respectively. The total DDT ranged from 820–7473 ng g^?1. The estimated daily intake varied from 260 to 4696 ng g^?1, ND-10551 ng g^?1 and ND-4237 ng g^?1 for DDE, DDD and DDT, respectively. These values are significantly higher than the FAO/WHO acceptable daily intake (ADI) of 20 ng g^?1. The ΣDDT was found to decrease with increasing age of the mothers. The observed high levels of DDE compared to DDT indicated chronic exposure of the mothers to DDT, which is metabolized to DDE and retained in the body.     

Persistent organochlorine pesticides,polychlorinated biphenyls,polybrominated diphenyl ethers in fish from coastal waters off Savannah,GA, USA

Contamination profiles of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) were determined in six fish species from three selected regions along coastal waters off Savannah, GA, USA. Concentrations of PCBs were predominant (12–493 ng g^?1 lw) followed by PBDEs (10–337 ng g^?1 lw), OCPs such as DDTs (2.7–153 ng g^?1 lw), chlordanes (3.8–34 ng g^?1 lw), cyclodienes (<0.1–35 ng g^?1 lw), mirex (<0.1–8.6 ng g^?1 lw), γ-hexachlorocyclohexane (<0.1–1.4 ng g^?1 lw), and hexachlorobenzene (<0.1–0.68 ng g^?1 lw). The results indicated no region-specific difference in the contaminants however inter-species as well as intra-species differences were evident. Comparison of DDTs, PCBs, and PBDEs profiles in fish with those from other countries revealed that fish from coastal waters off Savannah contained relatively less concentrations of PCBs and chlorinated pesticides, while PBDE concentrations were comparable or even higher than fish samples from other regions. Polychlorinated biphenyl congeners and chlorinated pesticide tempoal trend data exhibited no increase of contamination levels. The levels of PCBs and chlorinated pesticides in fish from Savannah coastal waters were below the Food and Drug Administrations (FDA) established limits for human consumption.     

Abstracts to forthcoming papers

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.     

Organochlorine pesticide and polychlorinated biphenyl residues in human milk from Tabriz,Iran

Human breast milk samples, collected during April 2007 in Tabriz, Iran, were analyzed for organochlorine (OC) pesticides, such as dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene (HCB), α, β, and γ-hexachlorocycloexane (HCH) isomers and six polychlorinated biphenyls (PCB) congeners (IUPAC Nos. 28, 52, 101, 138, 153, and 180). Organochlorine pesticides and OCB were both prevalent in the samples of human breast milk. Average concentrations of HCB, DDT, HCH, and PCB were 1020, 1930, 1660, and 690 ng g^?1 lipid weight, respectively. A positive correlation was observed between concentration of OC in human breast milk and mothers age with primiparae. Women having higher OC concentrations than multiparae women suggests that these parameters influence the OC burden in lactating women. The estimated tolerable daily intakes (TDIs) of HCH, HCB and PCB solely from human breast milk were 100, 46, and 43% of samples, respectively, exceeding guideline thresholds given as TDI proposed by Health Canada. Although high daily intakes may raise concerns for possible adverse effects of OC, women in Tabriz are recommended to breastfeed due to the numerous advantages for mother and child.     

The evolution of pollution profile and health risk assessment for three groups SVOCs pollutants along with Beijiang River,China

Three important groups of semi-volatile organic compounds (SVOCs), polycyclic aromatic hydrocarbons (PAHs), organic chlorinated pesticides (OCPs) and phthalate esters (PAEs), were produced by various human activities and entered the water body. In this study, the pollution profiles of three species including 16 PAHs, 20 OCPs and 15 PAEs in water along the Beijiang River, China were investigated. The concentrations of Σ₁₆PAHs in the dissolved and particulate phases were obtained as 69–1.5 × 10² ng L^?1 and 2.3 × 10³–8.6 × 10⁴ ng g^?1, respectively. The levels of Σ₂₀OCPs were 23–66 ng L^?1 (dissolved phase) and 19–1.7 × 10³ ng g^?1 (particulate phase). Nevertheless, higher levels of PAEs were found both in the dissolved and particulate phases due to abuse use of plastic products. Furthermore, non-cancer and cancer risks caused by these SVOCs through the ingestion absorption and dermal absorption were also assessed. There was no non-cancer risk existed through two kinds of exposure of them at current levels, whereas certain cancer risk existed through dermal absorption of PAHs in the particulate phase in some sampling sites. The results will show scientific insights into the evaluation of the status of combined pollution in river basins, and the determination of strategies for incident control and pollutant remediation.     

Histology of Sculpin spp. in East Greenland. II. Histopathology and trace element concentrations

Abstract

For many years, the sculpin has been utilized as a sentinel monitoring species for anthropogenic impacts on the marine environment. To further develop its potential as a screening model body burden of several trace elements, including cadmium (Cd), copper (Cu), mercury (Hg), lead (Pb) and selenium (Se), were investigated. In addition, histopathology in shorthorn sculpins (Myoxocephalus scorpius; n?=?20) and fourhorn sculpins (Myoxocephalus quadricornis; n?=?10) were examined at three sites around the Scoresby Sound settlement in Central East Greenland. Fourhorn sculpins caught at the most distant site from the settlement, contained significantly higher hepatic Cu and Cd concentrations as well as significantly elevated gill Pb levels compared to the shorthorn sculpins collected at two other sites closer to the settlement. Histological examinations showed that fish with significantly higher concentrations of hepatic Cd and Se exhibited greater nuclear alterations, interstitial hyperplasia/hypertrophy, interstitial mononuclear infiltrations and granulomas. Further, fish with higher Cd and Cu gill tissue levels displayed a significantly higher number of cytoplasmic alterations and lamellar epithelium lifting, hypertrophic and hyperplastic epithelium along with mucus cell hyperplasia. While the presence of liver lesions were not species or sex-specific, the presence of gill lesions decreased in the order female fourhorn sculpins?>?female shorthorn sculpins?>?male fourhorn sculpins?>?male shorthorn sculpins. Hepatic Hg concentrations exceeded known lowest observable effect doses (LOED) for fish (0.1–0.5?μg g^?1 ww) in 27% of fish, while liver Cd residues in 80% exceeded LOED (0.42–1.8?μg g^?1 ww). Based upon these results, data suggest that using the sculpin as a valuable sentinel fish species histopathology may serve as a reliable tool for assessing marine ecosystem exposure to trace metals. However, confounding physiological and ecological factors also need to be considered.     

Polychlorinated biphenyl (PCB) residues in European roe deer (Capreolus capreolus) and red deer (Cervus elaphus) from north-western Poland

The purpose of this study was to evaluate polychlorinated biphenyls (PCBs) contamination levels in roe and red deer from north-western Poland and to assess environmental pollution in this area. A quantitative analysis was conducted using a capillary gas chromatography/mass spectrometry method. The mean concentrations of ΣPCBs (sum of PCBs: 28, 52, 101, 138, 153, 180) in liver samples were 30.24±12.35 ng·g^?1 of lipid weight (l.w.) in roe deer and 60.13±14.23 ng·g^?1 l.w. in red deer, compared with 24.21±10.02 and 45.22±9.77 ng·g^?1 in the lungs of roe and red deer, respectively. PCBs 138, 153 and 180 were the dominant congeners in the liver samples of the analysed animals, whereas PCB 138 and 153 in the lungs. TEQs levels calculated for only dioxin-like PCBs were low: 0.32 and 0.29 pg WHO-PCB-TEQ·g^?1 fat in liver of red deer and roe deer, respectively. The mean PCB concentrations obtained in our study for organs of roe deer and red deer were several times lower than those reported elsewhere. These findings show that the investigated roe and red deer originated from an area with low levels of PCB contamination.     

Organochlorine pesticide residues in fodder from rural areas of Haryana,India

Residues of organochlorine pesticides (OCPs) namely 1,2,3,4,5,6-hexachlorocyclohexane isomers (HCH-isomers), 1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane (DDT) and its metabolites, and endosulfan stereoisomers were analyzed in dry and green fodder samples from rural areas of Ambala, Gurgaon, and Hisar districts of Haryana, India during winter, summer, and post-monsoon seasons. The HCH isomers γ-HCH and β-HCH, and DDT and its metabolites p,p′-DDD, p,p′-DDE, and p,p′-DDT had more traceability in test samples as compared to other isomers and metabolites studied. Total OCPs (ΣOCPs), i.e., ΣHCH, ΣDDT, and Σendosulfan were found to be the highest in wheat straw (1.1–1.2?mg?kg^?1) from Ambala and Gurgaon, followed by that in sorghum straw (0.46?mg?kg^?1) from Hisar. Dry fodder samples were found to have relatively higher residue levels than green fodders. In case of green fodder samples, maximum ΣOCP residues of 0.44?mg?kg^?1 were found in whole plant samples of sorghum from Gurgaon district followed by that in pearl millet (0.40?mg?kg^?1) from Ambala. The findings indicate highly significant differences (p?>?0.0001) in ΣOCPs and ΣDDT in wheat straw between different districts and reveal the persistence of OCP residues in both dry and green fodder samples in the study area.     

Polychlorinated biphenyls and organochlorine pesticides in amniotic fluids of pregnant women in south-central Turkey†

The concentrations of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were determined in amniotic fluid of 200 pregnant women from the Cukurova region of Turkey. The concentrations of OCPs [hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), dichlorodiphenyl trichloroethane (p,p′-DDT), and various metabolites], and different PCB congeners (28, 52, 101, 118, 138, 153, 180) were determined by gas chromatography with electron capture detection as follows: HCB 6.6 ± 4.7, ΣHCH 21.6 ± 14.2, ΣDDT 12.5 ± 7.5, and ΣPCBs 74.0 ± 54 ng mL^?1. Correlations of maternal or gestational age and levels of OCPs and PCBs were not significant. The levels of these organochlorine compounds (OCs) were below detection limit for 5% of the samples, 80% contained more than one OC. This study illustrates that prenatal exposure of a fetus to OCs is prevalent in the Cukurova region.     

The accumulation levels of heavy metals (Ni,Cr, Sr, & Ag) in marine algae from southwest coast of India

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.     

Determination of persistent organic pollutants in sediment and fish of the western coast of Alexandria,Egypt

Persistent organic pollutants (POPs) were recorded in sediment and fish samples collected from the western coast of Alexandria. Total hydrocarbons (aliphatic+PAHs ) in sediment ranged from 683.8 to 34670.1 ng g ^?1 with an average of 9286.9 ng g ^?1. The sum of C16–C34 of aliphatic fractions was<4000?ng g;^?1, indicating the presence of a fresh petroleum source. For all sediments, the anthracene/phenanthrene ratio was>0.1, suggesting the dominance of a pyrolytic source. Total aliphatics in different fish species ranged from 253 to 11?132 ng g;^?1, while total PAHs ranged from 3862 to 35?746 ng g;^?1 wet weight. Benzo[a]pyrene was the most dominant PAH fraction ranged from 1902.7 to 32 905.5 with an average of 9464.5?ng g;^?1 wet weight in all fish species. Concentrations of polychlorinated biphenyls (PCBs) ranged from 0.79 to 64.9?ng g;^?1 with an average 12.14?ng g;^?1 wet weight. The concentrations of organochlorines in fish species (Euthynnus alleferatus, Scomberomorus commerson, Sphyraena Sphyraena, Diplodus vulgaris, and Alepes djedaba) decreased following the order: PCBs>DDTs>HCHs>total cyclodienes. Concentrations of DDTs in fish tissues ranged from 4.89 to 36.37 ng g^?1 with an average of 16.4?ng g;^?1 wet weight. The concentrations of total HCHs ranged from 0.3 to 65.7?ng g;^?1 with an average of 16.35?ng g;^?1. The present study indicates: (1) fresh petroleum input where Pr/Ph>1; (2) PAHs in sediment<4000 ng g ^?1; (3) BaP concentration exceeded the permissible levels in Alepes djedaba species; (4) DDTs in sediment were below the effective range low level; (5) PCBs>effective range low and相似文献   

Seasonal and spatial character of PCBs in a chemical industrial zone of Shanghai,China

As one of China’s great metropolises, Shanghai is suffering from the impact of manufacture and the use of chemical industrial products, and it faces serious pollution from polychlorinated biphenyls (PCBs). Therefore, in this study, in order to assess the seasonal and spatial character of contamination from chemical industrial zones, the concentrations of PCBs have been measured in various environmental media, including soil, leaves, and atmospheric particulate samples collected in a chemical industrial zone of Shanghai and compared with samples from presumably unpolluted sites of rural areas. In soils, the PCB concentrations ranged from 0.5 ng g⁻¹ (unpolluted site) to 586.85 ng g⁻¹ (chlor-alkali industry site). The concentrations of PCBs in evergreen leaves ranged from 0.3 ng g⁻¹ to 32.46 ng g⁻¹, and more chlorinated biphenyls congeners, such as penta-biphenyls and hexa-biphenyls, were the dominant contributors in winter and spring. Seasonal differences and the constitution patterns of congeners might be affected by the temperature and industrial activities. The PCB concentrations in the leaves of deciduous trees increase over time as the leaves grow. The PCB concentration in atmospheric particulates was in the range of 9.22–14.15 × 10³ pg m⁻³, which might be the result of influence from climate and industrial activities. The relativity of PCB contents among the environmental media was discussed. The results in this paper provide an important profile of the current contamination status of a key chemical industrial zone in China.     

Fish as an indicator of aquatic environment: Multielemental neutron activation analysis of nutrient and pollutant elements in fish from Indian coastal areas

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.     

Assessment of metals in soil extracts and their uptake and movement within Tamarix nilotica at Lake Nasser banks,Egypt

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.     

Occurrence of PCBs and PAHs in an urban soil of Madrid (Spain)

Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) were analysed in surface soil samples collected in 2001–2002 at an open urban area of Madrid. In order to obtain representative samples, three collection points at the site were chosen. The most abundant PAHs and PCBs were phenanthrene, fluorene, pyrene, chrysene and benzo[a]pyrene and hexa- and heptachlorinated PCBs, respectively. The sum of selected PAHs (13 compounds) and PCBs (15 congeners) averaged 1 and 0.1?µg?g^?1, respectively. PCB levels in winter were 2–10 times higher than summer ones, while seasonal variation for most of PAHs were not observed. Good correlations among all PCBs were found. Five PAHs were also well correlated.     

Occurrence and profiles of polybrominated diphenyl ethers (PBDEs) in riverine sediments of Shanghai: a combinative study with human serum from the locals

Herein, we studied the occurrence and profiles of thirteen PBDE congeners in 30 river sediment samples from Shanghai, China. The concentrations of Σ₁₃PBDEs ranged from 110 to 13,071 pg g ^?1 dw, with an average value of 2,841 pg g ^?1 dw. BDE-209 was the predominant congener accounting for more than 65 % of total PBDEs, demonstrating that the major source of PBDEs in sediment samples was associated with the prevalent use of technical deca-BDE products. Moreover, low brominated BDEs in sediments also came from the degradation of higher brominated BDEs. In addition, taking into consideration of dietary exposure, PBDEs in serum samples collected from the locals were also detected with range of 419–26,744 pg g^?1 (average 5,561 pg g ^?1), which suggested a relatively low burden of PBDEs contamination to human body compared with the condition in other place. And in serum, low brominated compounds constituted the majority of total PBDE congeners.