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1.
The purpose of this study was to investigate the effect of sewage treatment on total mercury (THg) and methylmercury (MeHg) concentrations in domestic effluents and the contribution of urban sewage treatment facilities to THg and MeHg in rivers. We determined the concentrations of THg and MeHg in unfiltered samples of untreated and treated domestic sewage from the three treatment facilities and receiving river water within the City of Winnipeg. The concentrations of THg in the Red and Assiniboine rivers ranged from 3–31 ng/L. THg was related positively to suspended sediment concentrations in the rivers. The concentrations of MeHg in these rivers were usually 0.2–0.3 ng/L. THg concentrations in raw sewage varied widely, from 2–150 ng/L. Treatment removed an average of 88% of this mercury. MeHg concentrations in raw sewage were 0.5–4.3 ng/L, however, after treatment at two treatment facilities, MeHg was greatly reduced, usually to 0.1–0.4 ng/L. Most treated sewage, therefore, had MeHg concentrations that were similar to levels in the receiving rivers and the effect of discharged effluent was usually a change of about 2% or less on concentrations in the rivers. However, one of the facilities (the West End plant) was discharging higher concentrations of MeHg, up to 2 ng/L, causing calculated increases of up to 11% in the concentration of MeHg in the Assiniboine River.  相似文献   

2.
Enteromorpha linza (L.) J. Ag. was grown in full strength sewage effluent, various combinations of sewage effluent and seawater, and in natural seawater. It was found that full strength sewage effluent with a salinity of 14 supported best growth of the alga. After a 12 day cultivation period, growth ofE. linza in full strength sewage effluent and 75% sewage effluent- seawater mixture showed 3.5-fold and 2-fold increase in fresh weight over that grown in natural seawater; respectively. Uptake of PO inf4 sup3– -P, NH3-N and NO inf3 sup– -N by cells ofE. linza was extremely efficient in all tested media. Data obtained from the experiments indicated that inorganic nitrogen rather than phosphorus was the limiting nutrient factor for growth ofE. linza in full strength sewage effluent and in other sewage effluent- seawater mixtures. NH3-N at concentrations above 4.5 ppm was found to inhibit uptake of NO inf3 sup– -N in the same culture medium by the algal cells. The fact that sewage grownE. linza contained comparatively much higher protein content (30.2% dry weight) than that grown in natural seawater (12.5% dry weight) leads to the conclusion that sewage grownE. linza could serve as an economically feasible feed for livestock in Hong Kong where the sewage is characterized by having a salinity of approximately 14. It is proposed that this multicellular green alga is a suitable algal species to serve the dual function of wastewater purification through the production of algal protein from sewage effluent having high salinities.  相似文献   

3.
Abstract

The levels of TKN, orthophosphate, heavy metals and trace organics including total PCBs and PAHs in the sediments of the East River (Dongjiang) and various reservoirs in Hong Kong were chemically analyzed. It was found that the sediments of various sections of Dongjing and the Shenzhen Reservoir were contaminated by heavy metals at slight to medium levels. Generally speaking, the highest levels of Cd, Cu, Ni, Pb and Zn were recorded in the middle and lower tributaries of Dongjaing, particularly those near Tangxia and Guanlan. Slight amount of PCBs, PAHs were also detected in the lower sections of Dongjiang, indicating industrial contamination due to economic growth in the 1980–90s. Comparatively, only slight amounts of heavy metals were detected in the sediments of some Hong Kong reservoirs that store imported Dongjiang water. Moreover, trace organics including PCBs and PAHs were rarely detected in the reservoirs of Hong Kong. Nevertheless, the high acidity in the sediments of Hong Kong reservoirs is noteworthy. Results revealed that the Dongjiang waters were purified to a certain extent before being imported to and stored at the Hong Kong reservoirs. At present, health risks from the drinking water of Hong Kong are not apparent. However, the long-term trend of organic and inorganic contamination in Dongjiang should not be overlooked and remedial actions should be taken as early as possible. Collaboration between the governments of Hong Kong and Mainland China in tackling chemical pollution in drinking water is an example of cross-border cooperation and control measures should be stepped up as soon as possible.  相似文献   

4.
This is the first report of the detection of two new anti-influenza drugs, peramivir (PER) and laninamivir (LAN), in Japanese sewage effluent and river waters. Over about 1 year from October 2013 to July 2014, including the influenza prevalence season in January and February 2014, we monitored for five anti-influenza drugs—oseltamivir (OS), oseltamivir carboxylate (OC), zanamivir (ZAN), PER, and LAN—in river waters and in sewage effluent flowing into urban rivers of the Yodo River system in Japan. The dynamic profiles of these anti-influenza drugs were synchronized well with that of the numbers of influenza patients treated with the drugs. The highest levels in sewage effluents and river waters were, respectively, 82 and 41 ng/L (OS), 347 and 125 ng/L (OC), 110 and 35 ng/L (ZAN), 64 and 11 ng/L (PER), and 21 and 9 ng/L (LAN). However, application of ozone treatment before discharge from sewage treatment plants was effective in reducing the levels of these anti-influenza drugs in effluent. The effectiveness of the ozone treatment and the drug dependent difference in susceptibility against ozone were further evidenced by ozonation of a STP effluent in a batch reactor. These findings should help to promote further environmental risk assessment of the generation of drug-resistant influenza viruses in aquatic environments.  相似文献   

5.
吴健生  易腾云  王晗 《生态学报》2021,41(22):8718-8731
自然气候条件相近但社会经济制度差异显著的深圳与香港为我国制度探索与经济建设提供了重要窗口,两地的景观格局演变规律与发展趋势将深刻影响粤港澳大湾区的生态文明建设进程。以深港两地三期历史土地覆被数据为依据,应用CA-Markov模型预测了2030年景观类型,采用地学信息图谱、景观格局指数等方法对比了深港景观格局的时空分异特征,并通过地理探测器模型、logistic回归模型等方法,探讨了深圳与香港景观格局变化的驱动机制的异同。结果表明:(1)研究期内,深港两地景观格局变化显著,各景观类型之间互相转移频繁。深圳人造地表景观面积将持续增加,而香港则呈现先减少后增加的趋势;(2)深港两地的优势景观类型仍然是人造地表与林地。两地景观形状将趋于简单,相比于香港,深圳景观在呈现较高多样性的同时具有更为破碎化的特点;(3)夜间灯光所表征的经济发展水平对两地人造地表的扩张影响很大。在政策规划、社会经济水平、自然地理条件等多种因素的综合作用下,两地未来景观发展趋同存异。  相似文献   

6.
Alfalfa ( Medicago sativa L.) plants were grown in the absence or presence of the steroidal estrogens, estrone and 17β-estradiol, under varying conditions. Plants were analysed for the following parameters: plant weight, estrogen content, phytoestrogen content, degree of nodulation and nitrogen fixation activity. It was found that under controlled greenhouse conditions: (1) Treatment with estrogens in the range of 0.005 to 0.5 μg 1−1 increases both shoot and root dry weitht. In contrast, estrogen in concentrations of 50 to 500 μg 1−1 decreases plant growth. (2) The effect of estrogen of growth is most marked in the absence of nitrogen. (3) Estrone is more effective in increasing growth than 17 β-estradiol. (4) In the plants where estrogen induced growth there was no significant increase in nitrogen fixation activity and nodule number. (5) Endogenous estrogen content of the plant did not increase at concentrations (0.005-0.5 μg 1−1) which increased vegetative growth. (6) Endogenous estrogen content of the plant did increase at concentrations of estrogen (50-500 μg 1−1 which inhibited vegetative growth and nodule weight. It can be concluded that estrogen in concentrations found in sewage water (0.3 μg estrogen 1−1) can affect the vegetative growth of alfalfa plants.  相似文献   

7.
Estrone (E1), 17β-estradiol (E2) and 17α-ethynylestradiol (EE2) discharged from sewage treatment plants (STPs) into surface waters, are seen as a threat effecting aquatic life by its estrogenic character. Therefore, much research is conducted on the fate and removal of these compounds. Since these compounds are present in influents and effluents in the ng/l range, methods for detection deserve special attention. Most important processes that play a role in the removal of estrogens are: adsorption, aerobic degradation, anaerobic degradation, anoxic biodegradation and photolytic degradation. Halflifes tend to vary and are remarkably shorter when low initial concentrations are applied. In general anaerobic conditions result in longer halflifes then aerobic conditions. EE2 shows far most persistence of the compounds, thereby also the estrogenic effect in vitro is about 2–3-fold higher compared to E2. The three compounds show a higher affinity to sorb to sludge compared to other tested adsorption materials like sediment. Aerobic degradation is far the most efficient in removing these compounds, but adsorption seems to play a significant role in retaining the estrogens inside full-scale STPs. Removal rates in full scale plants depend on the HRT, SRT and loading rates, but lack of information on the exact dependency so far prevents an optimal design able to fully eliminate estrogens from wastewater.  相似文献   

8.
Labadie P  Peck M  Minier C  Hill EM 《Steroids》2007,72(1):41-49
Vertebrate-type sex steroids have been detected in a number of mollusk species and may play a role in the reproductive physiology of the animal. Mollusks are also exposed to exogenous estrogenic steroids that are present in sewage effluents, and these may add to the estrogenic burden of exposed animals. We investigated the uptake of estrogens in the blue mussel, Mytlius edulis and report for the first time the identity of estrogen fatty acid ester metabolites formed in vivo in an invertebrate. We exposed mussels to waterborne radiolabeled [(14)C]-17beta-estradiol (E2) or estrone (E1) and determined the nature of their metabolites using radio-HPLC and mass spectrometry (MS). After 13 days of exposure to 10ng/L E2, concentrations of radiolabeled residues were 2428-fold higher in M. edulis soft tissues compared with the ambient water concentration of E2. All the E2 residues in the mussel were present as a lipophilic ester which, in depuration studies, had a half-life of 8.3 days. Exposure of mussels to [(14)C]-E1 (70ng/L) resulted in formation of a similar lipophilic metabolite that after hydrolysis released [(14)C]-E2. Tandem MSMS analyses of the purified steroid ester fraction isolated from mussels exposed to either E2 or E1 revealed that they had the same composition and comprised C16:0, C16:1 and C16:2 esters of E2. This work reveals that in vivo E1 is rapidly metabolized to E2 in mussels prior to conjugation to C16 fatty acid esters, proving that C17-ketoreductase and C16 fatty acid acyl-CoA:E2 acyltransferase are important enzymes for the metabolism of estrogens in M. edulis.  相似文献   

9.
T Tanaka  M Katoh  A Kubodera 《Steroids》1986,48(5-6):361-368
The binding of catechol estrogens (2-hydroxyestrone, 4-hydroxyestrone, 2-hydroxyestradiol, and 4-hydroxyestradiol) to estrogen receptors in 7,12-dimethylbenz(a)anthracene (DMBA)-induced rat mammary tumor cytosols was investigated. Cytosol estrogen receptors exhibited high affinities (Ka = 1.12-1.88 X 10(8) M-1) for all catechol estrogens as well as estradiol. The receptor level of catechol estrogens (46.1-97.5 fmol/mg protein) was 1.6-3.0 times higher than that of estradiol; especially the binding of 4-hydroxyestrone to estrogen receptors was the highest of all catechol estrogens and estradiol. In judging the receptor level of more than 20 fmol/mg protein to be positive, the binding of catechol estrogens to estrogen receptors was approximately correlated with that of estradiol. The positive receptor level of catechol estrogens was found in a half of tumor cytosols which showed the negative receptor level of estradiol. These results suggested that characteristic estrogen receptors indicating high affinities for catechol estrogens might be present in rat mammary tumor cytosols.  相似文献   

10.
Aims:  Micro-organisms and molecular markers for microbial source tracking (MST) in coastal waters are often present at low numbers, and often exhibit significant variability in time and space. In this study, we investigated the uptake, accumulation, and persistence of human associated Enterococcus in the mussel Mytilus edulis .
Methods and Results:  The human associated molecular markers esp in Enterococcus faecium , and M66 in Enterococcus faecalis were targetted by PCR in seawater and mussel samples from coastal sites affected by sewage contamination. Both native mussels and mussels transplanted from pristine to polluted sites were included. The results showed that the esp and M66 markers were often not detectable in seawater whereas mussels were enriched in the markers. Human associated E. faecalis accumulated rapidly in M. edulis , and reached maximum levels after 4–6 h with concentration 30–300 times greater than in the surrounding seawater. Enterococcus faecalis retained in M. edulis showed a survival comparable to planktonic E. faecalis in seawater with half lives of 30 and 22 h, respectively. Human associated markers remained detectable for 120 h in M. edulis after faecal contamination.
Conclusions:  The study demonstrated that native and transplanted M. edulis can accumulate and retain human associated molecular markers relevant for MST.
Significance and Impact of the Study:  Mussels should be considered as additional targets in MST studies in coastal waters.  相似文献   

11.
J ones , K., B etaieb , M. & T elford , D.R. 1990. Thermophilic campylobacters in surface waters around Lancaster, UK: negative correlation with campylobacter infections in the community. Journal of Applied Bacteriology 69 , 758–764.
The incidence of campylobacter enteritis in Lancaster City Health Authority is three times the UK average for similar sizes of population and has marked seasonal peaks in May and June.
Environmental monitoring of surface waters around Lancaster showed that ther-mophilic campylobacters were absent from drinking water from the fells and from the clean upper reaches of the River Conder but were present in the main rivers entering Morecambe Bay, the lower reaches of the River Conder, the Lancaster canal, and seawater from the Lune estuary and Morecambe Bay. AH the surface waters tested showed the same seasonality, namely, higher numbers in the winter months and low numbers or none in May, June and July. The absence of thermo-philic campylobacters in the summer months may be due to high sunshine levels because experiments on the effects of light showed that campylobacters in sewage effluent and seawater were eliminated within 60 and 30 min of daylight respectively but survived for 24 h in darkness.
As the concentrations of campylobacters in surface waters were at their lowest precisely at the time of peak infections in the community it is unlikely that surface waters form Lancaster's reservoir of campyiobacter infection for the community.  相似文献   

12.
This study was performed to evaluate and compare the effects of estradiol sulfamate (J995) and estradiol (E2) on the hepatic levels of the estrogen receptor (ER) and its mRNA, in ovariectomized (OVX) and OVX+hypophysectomized (OVXHX) female rats and to study the effects on the liver-derived serum compounds angiotensin I, triglycerides, high-density lipoprotein (HDL) and cholesterol. ER concentrations were determined using ligand-binding assay (LBA) and enzyme immuno assay (EIA), and the mRNA levels using solution hybridization.

The rats were treated orally (p.o.) or subcutaneously (s.c.) for 7 days, with treatments initiated 14 days after surgery.

No differences were found in ER mRNA levels between J995 and E2 treated rats.

The s.c. administered estrogens increased ER levels in OVX rats. Addition of GH+DEX to OVXHX rats restored the ER to levels above those seen in intact rats, whereas simultaneous oral treatment with E2 significantly decreased ER levels again. The s.c. treatment with either J995 or E2 limited the increase caused by addition of GH+DEX.

After oral treatment angiotensin I levels were increased by E2, but not by J995, while triglycerides, HDL and cholesterol levels were decreased by oral E2, J995 showing a similar pattern but was less effective.

In summary, these results on hepatic ER levels and estrogen dependent compounds produced by the liver showed that J995 has a lower impact on the normal liver functions after oral treatment than E2. Thus, J995 is a very promising substance for development of oral estrogen treatment with reduced hepatic side effects.  相似文献   


13.
Transgenic marine medaka (Oryzias dancena) germlines were generated by the microinjection of the red fluorescent protein (RFP) reporter gene (rfp) driven by the endogenous choriogenin H gene (chgH) promoter. The selected transgenic lines contained multiple copies of the transgene (3–42 copies per cell) in their genomes. Although all the founders were mosaic, the transgene was stably transmitted from the F1 generation to all subsequent generations following a Mendelian pattern. Different transgenic lines showed different responsiveness to estradiol-17β (E2) exposure at the mRNA and protein levels, and the expression efficiency was dependent upon the transgene copy number. The induction of RFP was significantly affected by the developmental stage of transgenic larvae: later-stage larvae (older than 7 days post-hatching) showed higher sensitivity to E2 exposure than earlier-stage larvae. The response of transgenic expression to E2 was fairly dependent upon the E2 dose (200–3,200 ng/L) and exposure period (1–7 days), according to both a microscopic examination of RFP intensity and a qRT–PCR assay. The transgenic marine medaka showed similar transgenic responses to E2 under freshwater, brackish, and seawater conditions. In addition to E2, the transgenic RFP signal was also successfully induced during 1-week exposure to various other natural (1 μg/L estrone and 10 μg/L estriol) and synthetic (xeno)estrogens (0.1 μg/L 17α-ethynylestradiol, 1 μg/L diethylstilbestrol, and 10 mg/L bisphenol A). The efficiency of transgene expression varied greatly among the chemicals tested. The results of this study suggest that the chgHrfp transgenic marine medaka species will be useful in the in vivo detection of waterborne estrogens under a wide range of salinity conditions.  相似文献   

14.
Y.B. Ho 《Hydrobiologia》1990,203(1-2):73-81
The use of Ulva lactuca L. as an indicator of metal contamination was assessed by analysing the levels of Mn, Fe, Ni, Cu, Zn, Cd and Pb in the alga collected from 24 intertidal sites around the Island of Hong Kong. Twelve of the sites are in the rural southern parts of the Island where the coastal waters are relatively clean. The remaining 12 sites are located in the north and within Victoria Harbour which receives, apart from industrial effluents, untreated domestic sewage from a population of some 3.5 million. The mean levels of Mn, Fe, Ni, Cu, Zn and Pb in Ulva from the urban sites were respectively 4.0, 4.6, 1.8, 2.3, 2.4 and 4.6 folds those from the rural sites. However, similar levels of Cd were found in the alga amongst all the sites. Locations of high levels of metal contamination, particularly to the eastern end of the Harbour, have been identified. Preliminary results indicate that Ulva is a good indicator of Mn, Fe, Cu, Zn and Pb contaminations.  相似文献   

15.
Pharmaceuticals and personal care products (PPCPs), including estrogen pharmaceuticals, have been an environmental concern for well more than a decade, but no environmental emissions inventory for Canada has yet been published. Endogenous estrogens cannot be distinguished from the equivalent pharmaceutical estrogens in the environment. Therefore, data were compiled to estimate total environmental emissions of endogenous and retail pharmaceutical estrogens by the Canadian population for year 2007. Approximately 1,700 kg of pharmaceutical estrogens were dispensed through retail pharmacies in Canada in 2007. Of this amount, total environmental emissions were estimated to be approximately 730 kg, half to surface water via municipal sewage outfalls (> 90% via sewage treatment plants providing primary, secondary, or tertiary treatment), and half to the soil vadose zone and (potentially) groundwater via in situ sewage treatment systems. Approximately 960 kg of endogenous estrogens were excreted by the Canadian population, with about 420 kg reaching the environment, again approximately half to each of surface water and soil/groundwater. In situ sewage treatment may deliver an equivalent load of estrogens to the environment as do sewage treatment plants, despite servicing only 22% of the Canadian population.  相似文献   

16.
17.
The incidence of campylobacter enteritis in Lancaster City Health Authority is three times the UK average for similar sizes of population and has marked seasonal peaks in May and June. Environmental monitoring of surface waters around Lancaster showed that thermophilic campylobacters were absent from drinking water from the fells and from the clean upper reaches of the River Conder but were present in the main rivers entering Morecambe Bay, the lower reaches of the River Conder, the Lancaster canal, and seawater from the Lune estuary and Morecambe Bay. All the surface waters tested showed the same seasonality, namely, higher numbers in the winter months and low numbers or none in May, June and July. The absence of thermophilic campylobacters in the summer months may be due to high sunshine levels because experiments on the effects of light showed that campylobacters in sewage effluent and seawater were eliminated within 60 and 30 min of daylight respectively but survived for 24 h in darkness. As the concentrations of campylobacters in surface waters were at their lowest precisely at the time of peak infections in the community it is unlikely that surface waters form Lancaster's reservoir of campylobacter infection for the community.  相似文献   

18.
C Longcope  J H Pratt 《Steroids》1977,29(4):483-492
On the basis of the ratios of the estrogen conjugates in their urine (estriol/estrone + estradiol: E3/[E1+E2]), 19 women were divided into two groups: 9 women had ratios less than 0.6 and 10 women had ratios greater than 1.3. All women had measurements made of endogenous estrogens in their plasma by radioimmunoassay. They were then given constant infusions of 3H-estrone, 3H-estradiol and 14C-estriol during days 5-7 and days 20-22 of their cycles, and metabolic clearance rates (MCR) and blood production rates (PB) of estrone, estradiol and estriol were determined. Despite the wide disparity in their ratios of urinary estrogens, no differences could be found between the groups for the MCR's and PB's for all estrogens at either time of the cycle. The mean ratios of PB's (PB3/[PB2+PB1]) of estrone, estradiol and estriol ranged from 0.07 to 0.10 for each group during the cycle. The amounts of estriol entering the blood are small compared to the amounts of estrone and estradiol and do not correlate with the ratios of their urinary conjugates.  相似文献   

19.
目的:研究雌激素水平与围绝经期妇女心血管疾病的相关性。方法:回顾分析258例围绝经期患者的临床资料,研究心血管疾病发生情况。选取以合并心血管疾病患者为观察组,另选择无心血管疾病的患者为对照组,测定并比较两组患者的血清雌二醇(E2)水平。结果:258例患者中患有心血管疾病患者共50例(19.38%),观察组和对照组患者年龄差异无统计学意义(P〉0.05),血清E2含量分别为12.35±2.56pmol/L和46.84±3.85μmol/L,观察组显著低于对照纽(P〈0.05)。结论:心血管疾病的发生与雌激素水平下降直接相关。  相似文献   

20.
Y. B. Ho 《Hydrobiologia》1981,77(1):43-47
The amounts of tissue nitrogen, phosphorus, potassium, sodium, calcium and iron were estimated in the green alga Ulva lactuca L. collected from 9 rural and 14 urban littoral sites in the waters around Hong Kong Island during 1978 and 1979. The mean levels of tissue nitrogen and phosphorus were respectively 65% and 87% more in urban sites than in rural ones. Very significant correlation (r = 0.920) was found between the logarithmic concentration of seawater inorganic nitrogen and that of tissue nitrogen. The same applied to soluble reactive phosphorus in seawater and tissue phosphorus (r = 0.886). The levels of potassium, sodium and calcium in the alga were relatively uniform. However considerable variation in the level of iron was detected. The potential use of Ulva as an indicator species for eutrophication is discussed.  相似文献   

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