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1.
Daglish RW Nowak BF Lewis TW 《Archives of environmental contamination and toxicology》2004,47(1):110-116
Previous work has suggested that the ratio of copper residues to zinc in the gills of rainbow trout may indicate short-term exposure to increased levels of waterborne copper. However, the effect of exposure to a combination of increased copper and zinc concentrates in the water column was unknown. We exposed rainbow trout to 8 ± 2 g L–1, 40 ± 2 g L–1 and 90 ± 9 g L–1 of waterborne copper and 21 ± 3 g L–1, 129 ± 40 g L–1, and 202 ± 40 g L–1 of waterborne zinc in a 2-factor experiments and gill copper and zinc residues were examined. Other gill parameters analyzed included the concentrations of calcium, magnesium, sodium, and potassium, liver copper and zinc concentrations and plasma copper, calcium, sodium, and potassium are also reported here. Copper residues in the gill filaments were significantly higher in the highest level of copper exposure (high Cu, 4.06 g g–1; low Cu 2.41 g g–1; 0 Cu 2.01 g g–1; P = 0.001), whereas no differences were seen in zinc concentrations at any treatment level. Gill sodium and plasma calcium concentrations were also decreased at the highest waterborne copper concentrations. Although copper–zinc ratios in the gills were significantly different between the highest and lowest copper treatments (P = 0.002, F = 6.59), copper–sodium and copper–magnesium ratios were more sensitive to waterborne copper exposure (P = 0.001, F = 17.91 and P = 0.002, F = 15.45, respectively). These copper–metal ratios may be better indicators of copper loading in the water column. 相似文献
2.
P. H. Wendt R. F. Van Dolah M. Y. Bobo T. D. Mathews M. V. Levisen 《Archives of environmental contamination and toxicology》1996,31(1):24-37
Environmental concentrations and biological effects of certain metals and organic compounds found in wood preservatives were examined. The study focused on leachates from private residential docks in South Carolina tidal creeks. Copper, chromium, arsenic, and polynuclear aromatic hydrocarbons (PAHs) were measured in composite samples of surficial sediments and naturally occurring oyster populations (Crassostrea virginica) from creeks with high densities of docks, and from nearby reference creeks with no docks. In some cases, metal concentrations in sediments and oysters were higher immediately adjacent to dock pilings than they were elsewhere in the same creek. Sediments from most sites had concentrations of metals and total PAHs which were below levels reported to cause biological effects, however. Solid-phase Microtox® bioassays using whole sediments and rotifer bioassays using sediment pore water showed no significant differences in acute toxicity between creeks with and without docks. Oysters growing directly on dock pilings had significantly higher concentrations of copper than oysters growing at least 10 m away; however, there was no significant difference in the physiological condition of these oysters. Four-day field bioassays measuring percent survival of mummichogs (Fundulus heteroclitus), mud snails (Ilyanassa obsoleta), juvenile red drum (Sciaenops ocellatus), and juvenile white shrimp (Penaeus setiferus) showed no significant differences between sites near to and distant from newly constructed docks. Hatchery-reared oysters showed no significant differences between dock and reference sites in percent survival, growth, or bioaccumulation of metals after six weeks of exposure. The results suggest that, in estuarine environments with a moderate tidal range (1.5–2.0 m), wood preservative leachates from dock pilings have no acutely toxic effects on four common estuarine species, nor do they affect the short-term survival or growth of juvenile oysters. 相似文献
3.
Bosy-Westphal A Brabant G Haas V Onur S Paul T Nutzinger D Klein H Hauer M Müller MJ 《European journal of nutrition》2005,44(6):355-359
Summary
Objective
To examine
the determinants of adiponectin
levels (i) in 23 women with
anorexia nervosa (mean BMI
15.0 ± 1.2) and 43 healthy normal
weight females (mean BMI
22.3 ± 2.3; cross–sectional design)
as well as (ii) after six and twelve
weeks of weight gain in subgroups
of 18 and 11 anorectic patients
(mean weight gain 5.8kg; longitudinal
design). Plasma adiponectin
and leptin concentrations were
measured and their relationships
to body composition (fat mass by
bioelectrical impedance analysis
and anthropometrics), different
hormones and metabolic parameters
(insulin, ACTH, cortisol, glucose,
FFA, lipid profile) were investigated.
Results
In anorectic
patients, adiponectin levels were
higher (+29 %) and leptin levels
were lower (–75 %) than in control
subjects. There was a high variance
in adiponectin levels in patients
ranging from 2.6 to 18nM. Combining
patients and controls, an inverse
linear correlation was observed
between adiponectin levels
and fat mass (r = –0.36, p < 0.05),
while a positive exponential relation
was found between leptin levels
and fat mass (r = 0.82,
p < 0.001). In anorectic patients,
there were no significant correlations
between adiponectin and
hormonal or metabolic parameters.
Weight gain resulted in increasing
leptin (+0.17 ± 0.12nM;
p < 0.001) and a nonsignificant decrease
in adiponectin concentrations
(–1.12 ± 2.51nM). Changes in
leptin levels were mainly explained
by a gain in fat mass (r = 0.85,
p < 0.001). In contrast, changes in
adiponectin levels were closely
linked to initial adiponectin levels
(r = –0.84, p < 0.001) but not to
changes in fat mass or BMI.
Conclusion
Cross–sectionally serum
adiponectin concentration followed
a linear inverse function
with fat mass when patients and
controls were combined. Longitudinally
gain in fat mass was not associated
with changes in
adiponectin levels suggesting other
yet unidentified influences on
adiponectin secretion in anorexia
nervosa. 相似文献
4.
E. L. Avery R. H. Dunstan J. A. Nell 《Archives of environmental contamination and toxicology》1998,35(2):229-235
Sydney rock oysters, Saccostrea commercialis, were deployed for a 3-month period at sewage-disturbed and control marine locations in the Hunter Region, New South Wales,
Australia. After this period, the oysters were retrieved and the gills dissected and extracted for analysis of the saponified
lipid components (including fatty acids and sterols), using gas chromatography-mass spectrometry (gc-ms). Multivariate analysis
(discriminant function) of the gc-ms lipid profiles indicated that the lipid homeostasis in oysters from the sewage locations
was significantly different compared with that observed in oysters from control locations (p < 0.0001). The primary factor
discriminating between sewage and control locations was the level of β-sitosterol, a plant sterol derived from domestic sewage
and marine algae. The results indicate that gill lipid metabolism differentially alters in response to deployment of oysters
into either sewage-contaminated or control locations. This method of analysis provides a sensitive measure for the biological
impact of composite waste cocktails on strategically located marker organisms in affected environments.
Received: 24 July 1997/Accepted: 3 January 1998 相似文献
5.
Duthie SJ Gardner PT Morrice PC Wood SG Pirie L Bestwick CC Milne L Duthie GG 《European journal of nutrition》2005,44(4):195-203
Summary
Background
Fruit and
vegetable consumption protects
against cancer. This is attributed in
part to antioxidants such as vitamin
E combating oxidative DNA
damage. Anthocyanins are found in
significant concentrations in the
human diet. However, it remains to
be established whether they are
bioactive in vivo.
Aim
To investigate
the consequence both of vitamin
E deficiency on oxidative damage
to DNA and lipids and the
cytoprotective effect of nutritionally
relevant levels of cyanidin–3–glycoside both in vivo in rats and
in vitro in human colonocytes.
Methods
Male Rowett Hooded Lister
rats were fed a diet containing
less than 0.5 mg/kg vitamin E or a
vitamin E supplemented control
diet containing 100 mg d–tocopherol
acetate/kg. Half of the controls
and vitamin E–deficient rats
received cyanidin–3–glycoside
(100 mg/kg). After 12 weeks endogenous
DNA stability in rat lymphocytes
(strand breaks and oxidised
bases) and response to
oxidative stress ex vivo (H2O2;
200 µM) was measured by single
cell gel electrophoresis (SCGE).
Tissue levels of 8–oxo–7,8–dihydro–2–deoxyguanosine (8–Oxo–dG)
were measured by HPLC with EC
detection. D–tocopherol and lipid
peroxidation products (thiobarbituric
acid reactive substances;
TBARS) were measured by HPLC.
Rat plasma pyruvate kinase and
the production of reactive oxygen
by phagocytes were detected spectrophotometrically
and by flow cytometry
respectively. Immortalised
human colon epithelial cells
(HCEC) were preincubated in vitro
with the anthocyanins cyanidin
and cyanidin–3–glycoside and the
flavonol quercetin (all 50 µM) before
exposure to H2O2 (200 µM).
DNA damage was measured by
SCGE as above.
Results
Plasma and
liver d–tocopherol declined progressively
over 12 weeks in rats
made vitamin E deficient. Lipid
peroxidation was increased significantly
in plasma, liver and red cells.
Reactive oxygen levels in phagocytes
and plasma pyruvate kinase
were increased. Vitamin E deficiency
did not affect DNA stability
in rat lymphocytes, liver or colon.
Cyanidin–3–glycoside did not alter
lipid peroxidation or DNA damage
in rats. However, it was chemoprotective
against DNA damage in human
colonocytes.DNA strand
breakage was decreased
38.8 ± 2.2 % after pretreatment with
anthocyanin.
Conclusion
while it is
accepted that vitamin E alters lipid
oxidation in vivo, its role in maintaining
DNA stability remains unclear.
Moreover, whereas cyanidin–3–glycoside protects against
oxidative DNA damage in vitro, at
nutritionally relevant concentrations
it is ineffective against oxidative
stress in vivo. 相似文献
6.
G. J. Ramelow C. L. Webre C. S. Mueller J. N. Beck J. C. Young M. P. Langley 《Archives of environmental contamination and toxicology》1989,18(6):804-818
The edible parts of several species of fish and other marine organisms inhabiting the Calcasieu River/Lake, Louisiana were analyzed for Cd, Cr, Cu, Pb, Hg, Ag, Zn, and As. Concentrations of all metals measured in both intra and interspecies showed no significant variation with sample location. Differences in elemental concentrations were related to organism mobility and not to site-specific variations in metal loadings. Different species of finfish contained only trace amounts of Cd (0.02-0.08), Ag (<0.01–0.3), Pb (<0.2–0.5), and As (<0.1–0.3) mg kg–1. Concentrations of Cu and Cr were highly variable, in contrast to Zn, which was present in relatively constant amounts across all species (28 ± 7 mg kg–1). Sessile organisms such as oysters had the highest concentrations of heavy metals, including Cd. Periphyton and Zooplankton were the only groups that showed differences in metal concentrations with sampling location. 相似文献
7.
The benthic macroinvertebrates Lumbriculus variegatus and Chironomus riparius were used in toxicity and bioaccumulation tests to determine the toxic concentrations and accumulation potential of sediment associated herbicides. The tested chemicals were ioxynil, bentazone, and pendimethalin. The bioaccumulation tests with L. variegatus were performed in four different sediments, each having different characteristics. Water-only LC50 tests were performed with both L. variegatus and C. riparius. A sublethal effect of model compounds in sediments was assessed by a C. riparius larvae growth-inhibition test. Of the model compounds, ioxynil appeared to be the most toxic, with LC50 values 1.79 and 2.79 mg L−1 for L. variegatus and C. riparius, respectively. The LC50 water concentrations for bentazone were 79.11 and 62.31 mg L−1 for L. variegatus and C. riparius, respectively. Similarly, ioxynil revealed the highest bioaccumulation potential in bioaccumulation tests. The most important characters affecting chemical fate in the sediment seemed to be the organic matter content and the particle size fraction. The sediments with low organic material and coarse particle size consistently showed high bioaccumulation potential and vice versa. In C. riparius growth tests bentazone had a statistically significant effect on larval growth at sediment concentrations of 1160 and 4650 mg kg−1 (P<0.05). It is noteworthy that standard deviations tend to be greater at high chemical concentrations, which addresses the fact that part of the individuals started to suffer. Ioxynil had an effect on the larval growth in other test sediment at the highest concentration (15.46 mg kg−1 dw), in which head capsule length correlated with larval weight, decreasing toward higher exposure concentrations. The current results show the importance of sediment organic matter as a binding site of xenobiotics. 相似文献
8.
Joana Lourenço B. B. Castro R. Machado B. Nunes S. Mendo F. Gonçalves R. Pereira 《Archives of environmental contamination and toxicology》2010,58(4):1023-1031
Carassius auratus were exposed for 96 h to different concentrations of uranyl nitrate (corresponding to 0, 100, 450, and 2,025 μg U L−1) and killed after different postexposure periods (0, 48, and 96 h) to assess uranium bioaccumulation, peroxisome proliferation
(catalase [CAT]), lipid peroxidation (thiobarbituric acid reactive substances [TBARS]), and DNA integrity in erythrocytes
(comet assay). In addition, feeding behaviour was recorded as a general response to toxicant exposure. Results provided evidence
of uranium bioaccumulation in muscle of C. auratus after exposure to the highest concentrations (450 and 2,025 μg U L−1). This tissue was able to depurate uranium to control levels 96 h after exposure ceased. However, no perturbations in feeding
behaviour or cell damage were observed in the tested organisms, except for the apparent irreversible inhibition of CAT activity
immediately after exposure in the highest concentration tested. Data on DNA integrity (comets) showed that waterborne uranium
exposure was able to induce genotoxicity in C. auratus erythrocytes because fish exposed to all concentrations exhibited higher DNA damage than controls 96 h after exposure. No
DNA damage repair was apparent throughout the postexposure period, which was contrary to a recovery scenario. This experiment
provides evidence of uranium’s ability to induce physiologic impairment and genotoxicity in freshwater fish at environmentally
relevant concentrations. 相似文献
9.
Kristin E. Day J. L. Metcalfe S. P. Batchelor 《Archives of environmental contamination and toxicology》1990,19(6):816-827
Intracellular tissue concentrations of free amino acids (FAA) were monitored in caged mussels (Elliptio complanata) exposedin situ for 27–29 days and 77–79 days in the Yamaska River watershed (Quebec, Canada). Total concentrations of FAA (nmol/mg wet weight) increased in both mantle and adductor muscle tissue at several sites impacted by agricultural runoff and urban effluent from municipal sewage and light industries when compared to levels in mussels located at a site with little anthropogenic impact. Consistent changes in the per cent composition of individual FAA to the total FAA pool included decreases in serine, threonine, glycine and valine as well as increases in glutamic acid and glutamine at 27–29 days but results were not consistent with longer exposure and varied amongst sites. Few changes in total or individual FAA were observed in gill tissue. The results suggest that increases and/or decreases in total FAA in some tissues of freshwater bivalves may be indicative of generalized stress induced by a variety of environmental factors and may be useful as anin situ biochemical index of toxicity. 相似文献
10.
Fernandes C Fontaínhas-Fernandes A Peixoto F Salgado MA 《Ecotoxicology and environmental safety》2007,66(3):426-431
Heavy metal (Cu and Zn) concentrations in liver, gills, and muscle of leaping grey mullet, Liza saliens, from the Portuguese Esmoriz–Paramos coastal lagoon were measured to evaluate their bioaccumulation as a function of sediment contamination. The highest metal concentrations were observed in the liver (254 mg Cu kg−1) and gills (114 mg Zn kg−1). Bioaccumulation factors (BAFs) were found to follow the order: Cu-liver>Cu-gills>Cu-muscle and Zn-gills>Zn-liver>Zn-muscle. The highest BAFs were observed in the organs mainly implicated in metal metabolism and a significant positive relationship was found between BAFs and fish age. These results suggest the loss of homeostatic capacity of L. saliens under chronic metal exposure leading to bioaccumulation. Furthermore, Cu-liver and Zn-gills accumulation can be good environmental indicators of metal stress in L. saliens. 相似文献
11.
Jaroslav Mráz Eva Gálová Hana Nohová Dana Vítková 《International archives of occupational and environmental health》1994,66(3):203-208
The metabolism and toxicokinetics of cyclohexanone (CH-one), an important solvent and chemical intermediate, have been studied in volunteers during and after 8-h exposures to CH-one vapour at a concentration of 101, 207 and 406 mg · m–3. The pulmonary ventilation in these experiments was typically 11 1 · min–1 and retention in the respiratory tract was 58%. After exposure to CH-one, 207 mg · m–3, the metabolic yields of cyclohexanol (CH-ol), 1,2- and 1,4-cyclohexanediol (CH-diol) as determined in urine by a gas chromatographic method involving hydrolysis of glucuronide conjugate were 1.0% ±0.3%, 39% ± 5% and 18% ± 2% (n = 8), respectively. Peak excretion of CH-ol was achieved at the end of the exposure period, after which it decayed rapidly. Elimination of 1,2- and 1,4-CH-diol reached maximum values a few hours following exposure, with subsequent elimination half-times of 16 ± 2 and 18 ± 4 h, respectively. Repeated exposure to CH-one vapour (around 200 mg · m–3) for five consecutive days (8 h/day) resulted in cumulative excretion of CH-diols. The permeation rate of CH-one liquid through the skin was 0.037–0.069 mg · cm–2 · h–1 (n = 3), indicating that the contribution of percutaneous absorption to total CH-one occupational intake is of minor importance. CH-diols are recommended as biomarkers of exposure to CH-one. 相似文献
12.
Henry E. Tatem 《Archives of environmental contamination and toxicology》1986,15(2):171-183
Freshwater prawns,Macrobrachium rosenbergii, and clams,Corbicula fluminea, were exposed for 48 or 50 days to three concentrations of a river sediment that contained environmental contaminants such as polychlorinated biphenyls (PCBs) and metals. Sediment was obtained twice during 1980 from the same location. Prawns were exposed to the first batch, sediment 5–80, which contained higher concentrations of some metals and PCBs compared to sediment 11–80, used with the clams. The highest concentration of sediment 5–80 was toxic to the prawns; sediment 11–80 was not toxic to the clams. Tissue analyses of prawns for PCBs, as Aroclors® 1242 and 1254, demonstrated bioaccumulation. Maximum concentration of 1242 in prawns was achieved by day 7 while 1254 continued to accumulate in prawn tissues during the initial 40 days of the exposure period. The PCB sediment bioaccumulation factors (BAF) for prawns ranged from 0.11 to 0.90 for 1242 and 0.20 to 2.40 for 1254, and were highest for animals exposed to 10% sediment. Exposed clams also accumulated PCBs (1242 + 1254) from the sediment. Sediment BAFs for clams were 0.54 to 12.52 and were highest for animals exposed to 10% sediment. Analyses of clams for metals showed lead (Pb) in exposed animals at higher concentrations compared with controls. Bioaccumulation of Pb differed from PCB in that the Pb concentrations did not increase over time and concentrations were higher among animals exposed to 10% sediment compared to animals exposed to 100% sediment. Sediment 11–80 contained 99 mg/kg of Pb while exposed animals, at 48 days, contained approximately 2.2 mg/kg Pb. Analysis of clams for cadmium (Cd) showed exposed animals contained less Cd than controls. 相似文献
13.
Eating behaviour is of particular interest for research focusing on body weight status. However, little is known about the relationships of certain factors, especially social desirability, with self-reported eating behaviour such as cognitive restraint, uncontrolled eating, and emotional eating among young adult males and females. This study aimed to evaluate the relationships between eating behaviour and age, socioeconomic status (SES), physical activity (PA), body mass index (BMI), waist-to-height ratio (WHtR), and social desirability among university students. A cross-sectional study was conducted among 353 university students (59.2% females). Eating behaviour was assessed using the 13-item Three-Factor Eating Questionnaire (TFEQ-13). SES and PA were determined using self-reporting, and the Marlowe–Crowne Social Desirability Scale assessed social desirability. BMI and WHtR were calculated based on measured parameters. Associations between self-reported eating behaviour and other variables were assessed using Pearson’s correlation coefficient and multivariate general linear models. Cognitive restraint was positively correlated with BMI and WHtR in both males (r = 0.174, P = 0.036 and r = 0.194, P = 0.020, respectively) and females (r = 0.239, P < 0.001 and r = 0.165, P = 0.017, respectively), and emotional eating was positively correlated with BMI among females (r = 0.184, P = 0.008). Social desirability was negatively correlated with uncontrolled eating (r = −0.287, P < 0.001) and emotional eating (r = −0.301, P < 0.001) among females. There were no significant correlations between eating behaviour and age or socioeconomic status (P > 0.05). Multivariate analysis showed that, among males, PA had a main effect on emotional eating (ηp2 = 0.044, F = 6.276, P = 0.013). Among females, cognitive restraint was positively associated with PA (ηp2 = 0.034, F = 7.127, P = 0.008) and BMI (ηp2 = 0.038, F = 7.959, P = 0.005), and emotional eating with BMI (ηp2 = 0.032, F = 6.638, P = 0.011). Social desirability had the highest main effect on eating behaviour among females, being negatively associated with uncontrolled eating (ηp2 = 0.077, F = 16.754, P < 0.001) and emotional eating (ηp2 = 0.082, F = 18.046, P < 0.001). This study showed that PA, BMI, WHtR, and social desirability were associated with self-reported eating behaviour among university students. Social desirability bias should be considered when evaluating uncontrolled eating and emotional eating among females. 相似文献
14.
Immune effects of HFO on European sea bass,Dicentrarchus labrax,and Pacific oyster,Crassostrea gigas
Anne Bado-Nilles Claire Quentel Michel Auffret Stéphane Le Floch Béatrice Gagnaire Tristan Renault Hélène Thomas-Guyon 《Ecotoxicology and environmental safety》2009,72(5):1446-1454
The European sea bass, Dicentrarchus labrax, and the Pacific oyster, Crassostrea gigas, were exposed to a soluble fraction of heavy fuel oil for 5 and 9 days, respectively. The organisms were then transferred to non-contaminated seawater for 1 month. The bioaccumulation and elimination of PAHs in contaminated tissues were dissimilar between species. In fish, acenaphthene and naphthalene were detected and naphthalene was still detectable 30 days after the beginning of the recovery period. In oysters, on the other hand, pyrene and phenanthrene were bioaccumulated and 14 days after exposure no more PAHs were detected. Concerning innate immune parameters, the increase of haemolytic activity of the alternative complement pathway in fish and the reduction of phenoloxidase activity in oysters endured, respectively, 1 and 2 weeks in contaminated organisms. This indicates that these two enzymatic cascades could be quite useful for monitoring pollution by oil. 相似文献
15.
W. Popp C. Vahrenholz H. Przygoda A. Brauksfepe S. Goch G. Müller C. Schell K. Norpoth 《International archives of occupational and environmental health》1994,66(5):325-332
The lymphocytes of 25 hospital workers exposed to ethylene oxide and of a standardized control group were investigated for DNA damage (measured by alkaline filter elution) and sister chromatid exchange (SCE) frequencies. Additionally, the excretion of hydroxyethyl mercapturic acid (HEMA) in the 24-h urine of ten workers and ten control persons was determined. The peak levels of ethylene oxide in air during the first 8 min after opening of the sterilization unit were measured. Peak levels of ethylene oxide in the air of up to 417 ppm after opening of the sterilization unit were detected. In the alkaline filter elution assay we found significantly reduced elution rates in the exposed workers, indicating DNA-protein cross-links. The reduction of the elution rates through HVLP filters correlated significantly with the exposure classification (low, medium, high) (r = –0.45, P < 0.05) and the ethylene oxide peak level after opening of the sterilization unit (r = –0.42, P < 0.05). The SCE frequencies in the standardized control group were significantly elevated. With respect to (n = 78) historic control SCE values of our institute, the SCE values of the disinfectors were not significantly elevated (6.54 vs 6.27). The ethylene oxide-exposed workers did not have a greater percentage of high-frequency SCE cells. The mean HEMA concentration in the urine of the exposed workers was significantly elevated, but there were wide variations in HEMA concentrations and no correlation to ethylene oxide exposure. We conclude that the alkaline filter elution assay may be a sensitive parameter for monitoring the genotoxic damage in lymphocytes of ethylene oxide-exposed workers. Determination of the HEMA concentration in urine may be suitable for the differentiation between ethylene oxide-exposed and nonexposed groups, but not for individual biomonitoring. The result of the SCE determination indicates that the standardization of control groups with respect to sex, age, and smoking habit seems unsatisfactory. Therefore, it is recommended that in further studies control groups be constructed with respect to additional lifestyle factors. Additionally, enzyme polymorphisms — especially of glutathione transferase in the case of ethylene oxide exposure — should be taken into consideration and controlled. 相似文献
16.
E. F. Wirth G. I. Scott M. H. Fulton R. F. Van Dolah P. P. Maier N. Hadley J. W. Daugomah P. B. Key 《Archives of environmental contamination and toxicology》1996,30(3):340-348
In situ and laboratory bioassays using the eastern oyster, Crassostrea virginica, were undertaken in the Wright River Estuary, South Carolina, to determine the toxic potential of effluent and sediment from recently dredged sediments. Current standards (ASTM, USEPA, and USACE) rely solely on laboratory-based bioassays to assess toxicity of dredge spoils prior to disposal. These bioassays do not necessarily replicate the natural physicochemical estuarine processes, limiting the environmental realism of this approach. In this study, oysters were collected from a site on Leadenwah Creek (SC) and deployed in plastic cages anchored above the sediment and within the intertidal zone for 90 days at four dredge spoil disposal areas (18 sites total, one bushel/site). Oysters were also deployed at a reference site (New River Estuary, SC) and the original collection site. Trace metals and polycyclic aromatic hydrocarbons (PAHs) in tissue, sediment, and effluent samples as well as the assessment of oyster health in adults (% mortality and % reduction in potential yield) and larvae (larval development) were measured. Results indicated high arsenic concentrations in surface water samples (<10 to 147 g/L), some of which exceeded the USEPA chronic marine water quality criteria and sediment concentrations (<1.0–82.2 mg/kg), which also exceeded the ERM (70 mg/kg) and the ERL (8.2 mg/kg) for arsenic, and which may have contributed to the toxic response seen in deployed oysters. A positive relationship was also seen between the in situ percent reduction in potential yield and laboratory-derived data from larval oyster development bioassays. The advantage of the combined in situ/laboratory approach used in this study is the ability to resolve probable factors influencing the toxicity of these effluents to oysters. 相似文献
17.
Barbosa AC de Souza J Dórea JG Jardim WF Fadini PS 《Archives of environmental contamination and toxicology》2003,45(2):235-246
The population living along the riverbanks of the Amazon basin depends heavily on fish for nutritional support. Mono-methyl-mercury (MMHg) concentrates in fish, which can contaminate humans, the risk depending not only on fish MMHg concentration but also on the amount of fish consumed. We sampled nine locations of the Rio Negro basin, differing in water pH, Hg concentrations, and dissolved organic carbon (DOC), and determined total Hg from 951 fish samples of species representative of the food web: herbivorous, detritivorous, omnivorous, and piscivorous. Mercury concentrations varied widely in all species but showed a trend that depended on fish feeding strategies. The highest mean concentration was found in the piscivorous species (688.90 ng/g–1), followed by omnivorous (190.30 ng/g–1), detritivorous (136.04 ng/g–1), and herbivorous (70.39 ng/g–1). Fish Hg concentrations exceeding current safe limits (500 ng/g–1) for human consumption were found mainly in the piscivorous species (60%). Significant positive correlation between fish weight and Hg concentration was seen for the piscivorous Serrasalmus spp. (n = 326; r = 0.3977; p < 0.0001), Cichla spp. (n = 125; r = 0.4600; p < 0.0001), and Pimelodus spp. (n = 12; r = 0.8299; p = 0.0008), known locally as Piranha, Tucunaré, and Mandi, respectively. However, a negative correlation was seen for nonpiscivorous Potamorhina latior (n = 30; r –0.3763; p = 0.0404) and Leporinus spp. (n = 44; r = –3987; p = 0.0073), known as Branquinha (detritivorous) and Aracu (omnivorous). Fish-Hg concentrations in the acidic waters (pH range, 4.09–6.31) of the Rio Negro habitat, with its wide gradient of Hg concentrations (3.4–11.9 g/L–1) and DOC (1.85–15.3 mg/L–1)—but no history of gold mining activity—are comparable to other Amazonian rivers. Opportunity fish catches in the Rio Negro habitat show high muscle-Hg derived from natural sources, but no systematic association with site-dependent geochemistry. 相似文献
18.
William Shain Stephen R. Overmann Lloyd R. Wilson Jeanne Kostas Brian Bush 《Archives of environmental contamination and toxicology》1986,15(6):687-707
Rat pups were exposed to polychlorinated biphenyls (PCBs) from conception to weaning. Exposure occurred via feeding dams adulterated certified chow that was designed to contain 0, 3, 30, and 300 g/gm Aroclor® 1254. Tissue samples from rat pups and dams were analyzed for 67 different PCB congeners at birth and weaning to describe their accumulation during gestation and lactation. Bioaccumulation of PCB congeners was calculated as a function of their concentration in feed or milk. These data indicated that PCB congeners could be divided into three different groups. The a group was not avidly bioaccumulated. Congeners in the b group accumulated to widely different concentrations. This group contained primarily penta- and hexachlorinated biphenyls. The analysis of two families of pentachlorobiphenyls containing one ring with –2,3,4, or –2,4,5 chlorine substitutions indicated that molecular structure and not physico-chemical properties,e.g., gas Chromatographic retention time, determined bioaccumulation. The c group were all highly chlorinated congeners and bioaccumulated to nearly equal levels. Most congeners were concentrated in the milk when compared to the feed. When bioaccumulation data from pups at birth and weaning were compared, exposure was much greater during lactation than during gestation. The congener analysis showed that the same congeners were most avidly bioaccumulated during the periods of gestation and lactation, indicating that the increased accumulation during lactation was due to a higher effective dose. 相似文献
19.
Md. Saber Hussain Kaiser Jamil 《Archives of environmental contamination and toxicology》1992,22(2):214-218
The total protein distribution as a function of metal bioaccumulation in the weevils Neochetina eichhornae Warner through the trophic levels of the food chain was investigated. The accumulation of metals in insects was almost linear for all the metal concentrations tested. Mercury, Cd, Pb, and Zn induced dramatic differences in protein profiles in the insects in the SDS-Gel electrophoretic patterns. Of 40–50 g/100 mg of metal concentrations of Cd, Pb, and Zn estimated in the leaves of Eichhornae only about 4–9% could be estimated from the insect cell extract. Mercury concentration in the leaves was still lower i.e., 10–19% g/100 mg of metal conc. and the biotransfer of Hg into insect bodies was about 2–4%. It is concluded that the two metals Pb and Zn resulted in the selective synthesis and accumulation of proteins in the 70–80 KD range. The possibility of the disappearance of pre-existing proteins in the insects is discussed in the light of metal bioaccumulation. 相似文献
20.
Oikarinen S Heinonen SM Nurmi T Adlercreutz H Mutanen M 《European journal of nutrition》2005,44(5):273-280
Summary
Background & aim
The mammalian lignan enterolactone
(ENL) produced from plant
lignans, e. g. secoisolariciresinol
diglycoside (SDG), may protect
against various cancers in humans.
The present work aims to evaluate
the effect of flaxseed on tumour
formation in multiple intestinal
neoplasia (Min) mice, a model for
colon tumorigenesis.
Design
Male
and female Min mice were fed either
with a non–fibre control diet
or the same diet supplemented
with 0.5 % (w/w) defatted flaxseed
meal. Conversion of SDG to the
mammalian lignans enterodiol
(END) and ENL in the gut, and
plasma ENL, were measured by
HPLC with coulometric electrode
array detector (CEAD) and timeresolved
fluoroimmunoassay, respectively.
Wild–type mice were
also fed with the experimental diets
in order to see whether lignan
metabolism is different in Min and
wild–type mice.
Results
The total
number of adenomas or their size
in the small intestine was not different
in the flaxseed and control
groups. The flaxseed group had a
tendency for a decreased number
of colon adenomas in both genders.
Gender and genotype based
differences were found in the intestinal
ENL levels. When compared
to Min females, Min males
in the flaxseed group had several
fold higher ENL levels in the
small intestine (Min males
125 ± 124.5 nmol/g vs. females
22.8 ± 16.0 nmol/g, P = 0.048) and
caecum (47.6 ± 31.6 nmol/g vs. females
14.5 ± 6.6 nmol/g, P = 0.001).
Presence of adenomas in the gut
influences the intestinal lignan metabolism.
Min mice had less intestinal
END and ENL as compared
with the wild–type mice (P < 0.05).
Mean plasma ENL increased 7–fold
during the flaxseed feeding
(7 nmol/L in control vs. 50 nmol/L
in flaxseed group) but no differences
between gender and genotype
were found. The plasma ENL
level did not correlate with adenoma
number in the small intestine
and colon.
Conclusion
The
number of intestinal adenomas in
the Min mouse model is not related
to ENL level in plasma nor is it associated
with the levels of intestinal
lignans. A gender difference in
ENL lignan metabolism was found
in the gut but not in the plasma. 相似文献