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1.
This study examines the application of Ishikawa human endometrial adenocarcinoma cells to measure the estrogenic activity of fractionated extracts of sediments from Tokyo Bay, Japan. Estrogen stimulates alkaline phosphatase activity in this cell line. The results of these assays were compared with those of a yeast estrogen screen (YES) assay. The Ishikawa cell line bioassay showed higher sensitivity to 17beta-estradiol (median effective concentration [EC50], 10.7 pM) than did the YES assay (EC50, 480 pM). Fractionation of sediment extracts (all samples collected from 5 sites) showed that the nonpolar fraction was poisonous to yeast cells; the estrogenic activity of this fraction, therefore, could not be measured by YES. However, the nonpolar fraction did not kill the Ishikawa cells. The 17beta-estradiol-equivalent values of 15 extracts (3 fractions from each of 5 sediment samples) ranged from 5.7 to 697 pg/g dry weight according to the Ishikawa cell line bioassay. Chemical analysis using gas chromatography-mass spectrometry revealed that the highest concentrations of endocrine-disrupting chemicals were observed at the sampling station near the sewage treatment plant. The results support that the Ishikawa cell line bioassay is suitable for measuring the estrogenic activity of sediment samples.  相似文献   

2.
Several types of sediment quality guidelines (SQGs) are used by multiple agencies in southern California (USA) to interpret sediment chemistry data, yet little information is available to identify the best approaches to use. The objective of this study was to evaluate the predictive ability of five SQGs to predict the presence and absence of sediment toxicity in coastal southern California: the effects range-median quotient (ERMq), consensus moderate effect concentration (consensus MEC), mean sediment quality guideline quotient (SQGQ1), apparent effects threshold (AET), and equilibrium partitioning (EqP) for organics. Large differences in predictive ability among the SQGs were obtained when each approach was applied to the same southern California data set. Sediment quality guidelines that performed well in identifying nontoxic samples were not necessarily the best predictors of toxicity. In general, the mean ERMq, SQGQ1q, and consensus MECq approaches had a better overall predictive ability than the AET and EqP for organics approaches. In addition to evaluating the predictive ability of SQGs addressing chemical mixtures, the effect of an individual SQG value (DDT) was also evaluated for the mean ERMq with and without DDT. The mean ERMq without DDT had a better ability to predict toxic samples than the mean ERMq with DDT. Similarities in discriminatory ability between different approaches, variations in accuracy among SQG values for some chemicals, and the presence of complex mixtures of contaminants in most samples underscore the need to apply SQGs in combination, such as the mean quotient. Management objectives and SQG predictive ability using regional data should be determined beforehand so that the most appropriate SQG approach and critical values can be identified for specific applications.  相似文献   

3.
Polybrominated diphenyl ethers (PBDEs) were measured in surface sediments from 121 locations within the Southern California Bight. Site selection was based on a probabilistic approach to determine the spatial extent and magnitude of PBDE concentrations with known confidence intervals. Coastal embayments (including estuaries, marinas, ports, and bays) and the continental shelf out to the lower slope were sampled. Thirteen PBDEs were detected at 92 of the sites, with a geometric mean and maximum of 4.7 and 560?ng/g dry weight (sum of 13 congeners), respectively. The PBDE concentrations were higher in coastal embayments than in offshore locations. Embayments had an area-weighted geometric mean total PBDE concentration of 12 (95% confidence interval, 8.0-17) ng/g dry weight and a total PBDE mass of 110 (77-160) kg. The offshore stratum, which is 99% of the total area, had an area-weighted geometric mean total PBDE concentration of 2.0 (1.6-2.5) ng/g dry weight and a total PBDE mass of 860 (700-1,100) kg. The five highest PBDE concentrations were associated with the mouths of urban rivers, indicating that urban runoff is likely a major input of PBDEs to these coastal marine waters. The outfalls of wastewater treatment plants were not observed to be major sources. Environ. Toxicol. Chem. 2012; 31: 2239-2245. ? 2012 SETAC.  相似文献   

4.
Large quantities of DDT and polychlorinated biphenyls (PCBs) have been historically discharged to the Southern California Bight (SCB). While these contaminants have bioaccumulated in sediment-associated fishes, little data exist on concentrations of these compounds in pelagic forage species that are the likely food source for larger predatory mammals and birds. The goal of the present study was to assess the extent and magnitude of DDT and PCB bioaccumulation in the four major pelagic species of the SCB: Pacific sardine (Sardinops sagax), Pacific chub mackerel (Scomber japonicus), northern anchovy (Engraulis mordax), and California market squid (Loligo opalescens). A total of 99 composite samples were collected from commercial landing docks along the southern California coast from July 2003 to February 2004. Whole fish were homogenized and analyzed for total DDT (ortho- and para-isomers of DDT and its degradation products) and 41 PCB congeners. Virtually all of the samples of Pacific sardine, northern anchovy, and Pacific chub mackerel had detectable levels of total DDT. Only 50% of the California market squid samples had detectable total DDT. Northern anchovy had the highest total DDT concentrations (60 +/- 38 microg/kg wet wt), followed by Pacific chub mackerel (41 +/- 40 microg/kg wet wt), Pacific sardine (34 +/- 29 microg/kg wet wt), and California market squid (0.8 +/- 1.2 microg/kg wet wt). In general, concentrations were highest in the central SCB. An estimated 99% of northern anchovy, 83% of Pacific sardine, 33% of Pacific chub mackerel, and 0% of California market squid landings exceeded wildlife risk screening values for total DDT. Virtually none of the landings were estimated to exceed wildlife risk screening values for PCBs.  相似文献   

5.
Amphibians in alpine wetlands of the Sierra Nevada mountains comprise key components of an aquatic–terrestrial food chain, and mercury contamination is a concern because concentrations in fish from this region exceed thresholds of risk to piscivorous wildlife. Total mercury concentrations were measured in whole tadpoles of the Sierra chorus frog, Pseudacris sierra, two times at 27 sites from high elevations (2786–3375 m) in the southern Sierra Nevada. Median mercury concentrations were 14 ng/g wet weight (154 ng/g dry weight), which were generally low in comparison to tadpoles of 15 other species/location combinations from studies that represented both highly contaminated and minimally contaminated sites. Mercury concentrations in P. sierra were below concentrations known to be harmful in premetamorphic tadpoles of another species and below threshold concentrations for risk to predaceous wildlife. Concentrations in tadpoles were also lower than those observed in predaceous fish in the study region presumably because tadpoles in the present study were much younger (1–2 months) than fish in the other study (3–10 years), and tadpoles represent a lower trophic level than these fish. Mercury concentrations were not related to distance from the adjacent San Joaquin Valley, a source of agricultural and industrial pollutants.  相似文献   

6.
A multimetric benthic assessment method was developed for two benthic assemblages in the San Francisco Estuary (USA) using data from several monitoring programs collected over five years. Assessment indicators used were total number of taxa, total abundances, oligochaete abundances, number of molluscan taxa, number of amphipod taxa, and Capitella capitata and Streblospio benedicti abundances. Exceedances of the maximum or minimum indicator values in reference samples were used to assess test samples using a weight-of-evidence to obtain an assessment value. Only 2.5% of the samples from the deeper, offshore sites had benthic impacts, 14.3% of the samples from near wastewater discharges had impacts, and 78.3% of the samples from the estuary margins and channels were impacted. Impacted samples from both assemblages had significantly higher mean effects range-median quotient values (mERMq) than reference samples, total organic carbon (TOC) was significantly higher in the impacted samples from the mesohaline assemblage, and percent fines was significantly higher in the impacted samples from the polyhaline assemblage, reflecting the close associations of contaminants with fine sediments and organic material. In samples with mERMq below 0.050, there were no benthic impacts. The incidence of impacts remained low (9.4%) at mERMq below 0.146, but when mERMq was above 0.146, 68.2% of the samples had benthic impacts, and samples with mERMq above 0.740 were always impacted.  相似文献   

7.
1,1,1-Trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its primary metabolites (DDTs) and polychlorinated biphenyls (PCBs) are a major source of concern in the Southern California Bight (SCB), USA. The fate of DDTs and PCBs is a key element in assessing the effects imposed by these potential carcinogens on the marine ecosystem. We found that DDTs and PCBs remained widely distributed in the overlying water, sediment, polychaetes, and liver and muscle tissues of the hornyhead turbot (Pleuronichthys verticalis) collected from three nearshore locations of the SCB with different levels of contamination. Student's t tests indicated that the measured partition coefficients between the nonaqueous phases (sediment, polychaete, and fish) and overlying water at a heavily contaminated location were significantly greater than those predicted by the equilibrium partitioning theory (EPT). Measured partition coefficients between the nonaqueous phases and overlying water for a few DDT components at two other stations (moderate and low contamination) were also generally greater than the EPT predictions. On the other hand, DDTs and PCBs in polychaetes and fish tissues may be taken up from sediments via equilibrium partitioning or from food sources. These findings are suggestive of the possibility that contaminated sediments may have become an important source of contamination.  相似文献   

8.
9.
Anthocyanin from purple sweet potato (PSP) extracted by microwave baking (MB) and acidified electrolyzed water (AEW) exhibited antioxidant activity. After further purification by macroporous AB-8 resin, the color value of PSP anthocyanin (PSPA) reached 30.15 with a total flavonoid concentration of 932.5 mg/g. The purified extracts had more potent antioxidant activities than the crude extracts. After continuously administering the PSP extracts to 12-mo-old mice for 1 mo, the anti-aging index of the experimental group was not significantly different from that of 5-mo-old mice. To a certain degree, PSPA was also effective for controlling plasma glucose levels in male Streptozocin (STZ)-treated diabetic mice. In addition, the extracts inhibited Sarcoma S180 cell growth in ICR mice. Mice consuming the PSP extracts formed significantly fewer and smaller sarcomas than mice consuming the control diets. The highest inhibition rate was 69.03%. These results suggest that anthocyanin extracts from PSP not only exert strong antioxidant effects in vitro, but also had anti-aging, anti-hyperglycemic, and anti-tumor activities.  相似文献   

10.
11.
Pesticide formulators formerly operating at Lauritzen Channel, a portion of San Francisco Bay near Richmond (CA, USA), caused contamination of sediment with dichlorodiphenyltrichloroethane (DDT). The present study evaluated the distribution of residual DDT in channel sediment six years following extensive remedial dredging. High DDT concentrations (up to 252 mg/ kg) were found in Young Bay Mud sampled across the channel. Particle analyses showed most of the contamination is contained in the clay/silt sediment fraction, and desorption tests showed that availability is greater for DDT metabolites than parent DDT. The present study examined the feasibility of using activated carbon amendment to sequester DDT from sediment, including an evaluation of reactivated carbon as a less costly alternative to virgin activated carbons. Treatment success of activated carbon amendment to sediment collected from Lauritzen Channel was measured by reductions in aqueous equilibrium concentrations and uptake in semipermeable membrane devices (SPMDs). Four different activated carbons were tested and, after one month of treatment with 3.2 weight % carbon, DDT aqueous equilibrium concentrations were reduced up to 83% and SPMD uptake was reduced up to 91%. Reactivated carbon was comparable with virgin carbons in all tests. Reduction in SPMD uptake of DDT by treatment with 3.2% reactivated carbon increased to 99% after 26 months of treatment. The effectiveness of activated carbon was dependent on the type, size, dose, and contact time. The results show the potential usefulness of activated carbon amendment as a follow-up remedial technology for management of residuals after dredging contaminated sediment.  相似文献   

12.
13.
BACKGROUND: In vitro evidence exists for the potential antioxidant benefits of procyanidin-rich extracts, but in vivo studies are scarce. We have evaluated the effects of selected procyanidin-rich extracts on oxidative stress in rats in condition of prolonged consumption of these compounds and also after single administration i.e. in postprandial conditions. METHODS: Rats were fed for 8 weeks with diets supplemented with either a grape seed extract (GE), a pine bark extract (PE), or a high-degree polymerized pine bark extract (HPE). An additional study was performed in order to assess the postprandial effect of these extracts on plasma antioxidant capacity. The ferric-reducing antioxidant power (FRAP) and thiobarbituric acid-reactive substances (TBARS) were determined in plasma. For lipid peroxidation study of heart tissue, homogenates were prepared and TBARS were measured after lipid peroxidation induced by FeSO4-ascorbate. RESULTS: After 8 weeks of dietary treatment, total antioxidant capacity in plasma was significantly higher in the GE and PE groups as compared with the other two groups. Plasma TBARS concentrations and heart susceptibility to peroxidation were not significantly different between the groups. In the postprandial state, by comparing plasma antioxidant capacity 2 hours after ingestion of the different procyanidin-rich extracts (500 mg/kg body weight), we observed that FRAP values were higher in the procyanidin-rich extracts groups as compared with the control group. Moreover, plasma FRAP concentration was significantly higher in the GE group as compared with the other groups. CONCLUSION: The results of the present experiment constitute positive evidence for an in vivo antioxidant effect at the plasma level of procyanidin-containing plant extracts.  相似文献   

14.
自来水及水源水有机提取物类雌激素活性研究   总被引:11,自引:3,他引:8  
解玮  屈卫东  朱惠刚 《卫生研究》2003,32(6):541-543
为了检测自来水及水源水有机提取物的类雌激素活性 ,应用环境雌激素基因重组酵母、细胞增殖和子宫增重等三项短期生物学实验进行测定。结果发现 :水样有机提取物在相当于原水量 50ml时两项体外实验均检出雌激素活性 ,原水量 2 50ml时细胞增殖效应达到最大 ,以后随原水量增大细胞增殖效应逐步减弱。原水量 12 50ml时酵母菌β -半乳糖苷酶活性最强 ,以后随原水量增大 β -半乳糖苷酶活性逐步减弱。水厂水源水有机提取物低、中剂量组受试小鼠子宫湿重增加 ,与对照组比较有统计学意义 ,高剂量组湿重减少。提示水源水有机提取物具有类雌激素活性。采用这三项实验组成的生物学检测程序具有一定的灵敏度 ,且较快速、方便。  相似文献   

15.
The present study compared estrogenicity measured by in vitro bioassay and estrogenicity estimated by the chemical analysis of seawater from Suruga Bay, Japan. Nonylphenol, bisphenol A, estrone, 17beta-estradiol, nonhydroxy polycyclic aromatic hydrocarbons, and hydroxy polycyclic aromatic hydrocarbons, some of which show estrogenic activity, were selected as the target compounds. The yeast two-hybrid system was used to evaluate the estrogenic activities of seawater and chemicals with or without rat liver S9. Concentrations of estrogenic compounds in seawater were measured by chemical analysis using gas chromatography/ mass spectrometry. The main estrogenic compounds in seawater were estrone (< or = 9.2 ng/L), bisphenol A (< or = 1,070 ng/L), and nonylphenol (< or = 276 ng/L). The highest estrogenic activities in seawater were observed near a sewage treatment plant, but the predicted potencies based on the chemistry data were higher than those observed experimentally for the estrogenic activity in seawater. The estrogenicity measured by bioassay was raised considerably after S9 treatment; this observation was limited to the zone of freshwater immediately adjacent to the wastewater outfall.  相似文献   

16.
17.
In this study, ethanol extracts of stems and leaves of Costus cf. arabicus L. were evaluated for antibacterial activity against multidrug-resistant strains of Escherichia coli and Staphylococcus aureus. The antibacterial and modulatory activities of the extracts were assayed by microdilution. The light-enhanced antibacterial activity was assayed by a light regimen. The growth of the bacteria tested was not inhibited by the extracts. The minimum inhibitory concentration values were ≥1,024 μg/mL. However, the antibiotic activity of aminoglycosides was synergistically enhanced when these extracts at subinhibitory concentrations were combined with the antibiotics. Also, both extracts showed activity against the wild-type bacterial strains, but the leaf extract was the more active extract, being active against both S. aureus and E. coli. Therefore, we conclude that the ethanol extracts of stems and leaves of C. cf. arabicus L. have potential light-induced antibacterial activity and synergistic antibiotic activity. This study showed that these extracts may be a promising source of antibacterial and modulatory agents.  相似文献   

18.
Extracts of sediments from rivers in an industrialized area in the Czech Republic were used to evaluate suitability of a simple in vitro bioassay system to detect estrogen receptor (ER)-mediated activity in the complex mixture. Total estrogenic activity was detected by measuring luciferase activity in a stably transfected cell line containing an estrogen-responsive element linked to a luciferase reporter gene. For appropriate interpretation of ER-mediated activity, the effect of sediment extracts on the cell cytotoxicity was assessed at the same time. All sediment samples elicited considerable estrogenic activity. Fractionation of the extracts along with bioassay testing and subsequent instrumental analysis allowed the estrogenic fractions to be identified. The Florisil fraction, which was intermediate in polarity, was the most estrogenic. Instrumental analysis documented that the concentration of the degradation products of alkylphenol ethoxylates did not occur at sufficient concentrations to account for the estrogenic activity. Mass-balance calculations and testing of fractions confirmed that certain polycyclic aromatic hydrocarbons (PAHs) or their metabolites were the most likely compounds contributing to estrogenicity. Some other compounds, such as PCNs and PAH derivatives, that were present in the first and second fraction were tested for their potential estrogenic activity. Their ER-mediated activity and contribution to the overall responses of the complex extracts were very low. The concentrations of 17β-estradiol present in the bioassay media was an important factor for the evaluation of (anti)estrogenicity of single compound(s) or complex mixtures. Received: 15 June 2001/Accepted: 27 February 2002  相似文献   

19.
Coagulant dosing of stormwater runoff with polyaluminum chlorides (PACs) is used in numerous waterbodies to improve water clarity, but the potential risks of PACs to aquatic organisms in Lake Tahoe, California are not fully understood. To assess these risks, the USEPA 3-species toxicity test and a non-standard fish test using Japanese medaka (Oryzias latipes) were used to determine the toxicity of PAC-treated and non-treated stormwater samples to aquatic species. Stormwater samples were collected from three sites representing runoff from different urbanized areas in May 2004; samples received coagulant dosing using three different coagulants (JC1720, PAX-XL9, Sumalchlor50) at levels optimized with jar testing. Raw stormwaters were toxic to algae and fathead minnows (mortality). Treatment with coagulants increased toxicity to zooplankton (reproduction) and had no consistent effects on the other toxicity metrics.  相似文献   

20.
Most analyses of prenatal substance use focus on individual level correlates and ignore community level variables and the effect of the dependency of respondents within communities. This analysis uses multilevel logistic regression models to more accurately assess the correlates of perinatal substance use in California. Statistical results indicate that a significant portion of substance use can be attributed to neighborhood heterogeneity, and that traditional models of substance use may inaccurately attribute this variation to individual level regression coefficients. Substantive results indicate that levels of neighborhood public assistance had an independent, significant effect on the prevalence of all substances tested for except alcohol. Black women had higher predicted prevalence risks for alcohol and cocaine while White women had higher predicted risks for tobacco, marijuana and amphetamines. Racial contrasts were non-significant for the overall illicit drug category and opiates, after controlling for neighborhood public assistance. Finally, individual level variables, with the exception of age, were not moderated by levels of neighborhood public assistance.  相似文献   

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