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1.
The goal of this study was to quantify the microbial load (enterococci) contributed by the different animals that frequent a beach site. The highest enterococci concentrations were observed in dog feces with average levels of 3.9 × 107 CFU/g; the next highest enterococci levels were observed in birds averaging 3.3 × 105 CFU/g. The lowest measured levels of enterococci were observed in material collected from shrimp fecal mounds (2.0 CFU/g). A comparison of the microbial loads showed that 1 dog fecal event was equivalent to 6940 bird fecal events or 3.2 × 108 shrimp fecal mounds. Comparing animal contributions to previously published numbers for human bather shedding indicates that one adult human swimmer contributes approximately the same microbial load as one bird fecal event. Given the abundance of animals observed on the beach, this study suggests that dogs are the largest contributing animal source of enterococci to the beach site.  相似文献   

2.
Although urban wet weather discharges may have elevated concentrations of fecal indicator bacteria impacting water quality at swimming beaches, not all of these bacteria may arise from human sources. In this study, the contribution of non-human fecal indicator bacteria was quantified by sampling coastal reference beaches in southern California. Samples were collected at beaches near stormwater discharges from undeveloped watersheds and analyzed for total coliform, Escherichia coli, and enterococci. Surfzone samples exceeded water quality thresholds >10 times more frequently during wet weather than dry weather. Exceedences were greatest <24 h following rainfall, then steadily declined on successive days. Early season storms exceeded thresholds more frequently, and by greater magnitude, compared to late season storms. Large storms exceeded thresholds more frequently than smaller-sized storms, partly due to the breaching of sand berms. When discharges did reach the surf zone, bacterial concentrations in the wave wash were correlated with watershed bacterial flux.  相似文献   

3.
Biochemical fingerprinting (BF) databases of 524 enterococci and 571 Escherichia coli isolates and an antibiotic resistance analysis (ARA) database comprising of 380 E. coli isolates from four suspected sources (i.e. dogs, chickens, waterfowls, and human sewage) were developed to predict the sources of faecal pollution in a recreational coastal lake. Twenty water samples representing four sampling episodes were collected from five sites and the enterococci and E. coli population from each site were compared with those of the databases. The degree of similarity between bacterial populations was measured as population similarity (Sp) coefficient. Using the BF-database, bacterial populations of waterfowls showed the highest similarity with the water samples followed by a sewage treatment plant (STP). Higher population similarities were found between samples from STP and water samples especially at two sites (T2 and T3) which were located near the sewerage pipes collecting wastewater from the study area. When using the ARA-database, the highest similarity was found between E. coli populations from STP and water samples at sites T2 and T4. Both faecal indicators and as well as methods predicted human faecal pollution, possibly through leakage from submerged sewerage pipes. The results indicated that the Sp-analysis of faecal indicator bacterial populations from suspected sources and water samples can be used as a simple tool to predict the source(s) of faecal pollution in surface waters.  相似文献   

4.
Traditional and molecular methods (PCR) were used to detect, quantify and identify the source of fecal pollution in coastal sites of Puerto Rico and Trinidad. Enterococci and Escherichia coli standard plate counts were used as a general indicator of fecal contamination while the PCR detection of Bifidobacteria adolescentis and human or bovine specific Bacteroidales were used to examine potential sources. Seven of 14 sites in Trinidad including Maracas Bay which is a major public beach contained significant fecal contamination based on enterococci numbers counts exceeding established thresholds for areas of direct contact. Forty six percent of the 27 stations in Puerto Rico were over the established thresholds for enterococci and 49% according to E. coli counts. About 31% of the stations examined in Puerto Rico had evidence of human derived fecal contamination. Human fecal pollution was detected in only one station from Trinidad. Bovine derived contamination was detected only once.  相似文献   

5.
The pharmaceutical residues in waste water from the largest sewage treatment plant (STP) in Northern Taiwan and in seawater around the effluent discharged area were determined. An environmental risk assessment for the marine environment was conducted based on the environment risk quotient (ERQ). The concentrations of the analyzed compounds in STP influent and effluent were generally higher than those found in coastal seawater. Relatively higher values were found at the estuarine mouth and the discharged area, suggesting that the STP effluent is a point source. The removal efficiency and half life of the analyzed compounds were 6.3-46.8% and 3-18 days, respectively. The ERQ value theoretical calculation was generally greater than 1. However, when the measured concentrations replaced the predicated concentrations, the ERQ values were considerably lower than 1. Therefore, our results call for a re-evaluation of the risks posed by pharmaceuticals to coastal marine ecosystems in Northern Taiwan.  相似文献   

6.
Urban sewage is considered one of the most important sources of marine pollution in South America, because most coastal cities do not have proper facilities to treat and dispose of sewage. The Paranaguá estuarine system is an important estuarine environment of the South American coast where fishing, urban and tourist activities, industries and the main Brazilian grain shipping port are potential sources of pollution in this area. The anthropogenic input of sedimentary organic matter, represented by sewage contribution, was evaluated by fecal steroid concentrations. The coprostanol levels were comparatively low (<0.10 μg g−1), except at the sites close to Paranaguá city, where the coprostanol concentration reached 2.22 μg g−1 showing strong sewage contamination. Fecal steroid levels were comparable to the lower to midrange concentrations reported for coastal sediments worldwide. The results of this work demonstrated that sewage pollution can be considered a problem for a small part of the Paranaguá estuary.  相似文献   

7.
The occurrence and concentration of the fuel additive methyl-tert-butyl ether (MTBE) were measured in dry weather runoff, municipal wastewater and industrial effluents, and coastal receiving waters in southern California. Combined, refineries and sewage treatment plants release approximately 214 kg day(-1) of MTBE into the marine environment, with Santa Monica Bay receiving most (98%) of this discharge. Dry weather urban runoff was analysed for samples collected from 25 streams and rivers, and accounted for less than 0.5% of the mass of MTBE discharged to coastal waters. Receiving water samples were collected from 23 stations in Santa Monica Bay, Los Angeles Harbour and Mission Bay or San Diego Bay. MTBE was detected at low concentrations near effluent discharges, however there was no evidence of baywide MTBE contamination related to these outfalls. Marinas and areas used intensively for recreational boating had the highest average MTBE concentration (8.8 microg l(-1)). Surface water contamination was most widespread in San Diego Bay and Mission Bay, areas with no refinery or sewage treatment plant inputs.  相似文献   

8.
Human fecal contamination of coral reefs is a major cause of concern. Conventional methods used to monitor microbial water quality cannot be used to discriminate between different fecal pollution sources. Fecal coliforms, enterococci, and human-specific Bacteroides (HF183, HF134), general Bacteroides-Prevotella (GB32), and Clostridium coccoides group (CP) 16S rDNA PCR assays were used to test for the presence of non-point source fecal contamination across the southwestern Puerto Rico shelf. Inshore waters were highly turbid, consistently receiving fecal pollution from variable sources, and showing the highest frequency of positive molecular marker signals. Signals were also detected at offshore waters in compliance with existing microbiological quality regulations. Phylogenetic analysis showed that most isolates were of human fecal origin. The geographic extent of non-point source fecal pollution was large and impacted extensive coral reef systems. This could have deleterious long-term impacts on public health, local fisheries and in tourism potential if not adequately addressed.  相似文献   

9.
Water, sponge and coral samples were collected from stations impacted by a variety of pollution sources and screened for human enteric viruses as conservative markers for human sewage. While human enteroviruses and adenoviruses were not detected, noroviruses (NoV; human genogroups I and II) were detected in 31% of samples (especially in sponge tissue). Stations near inlets were the only ones to show multiple sample types positive for NoV. Fecal indicator bacteria and enteric viruses were further evaluated at multiple inlet stations on an outgoing tide. Greatest indicator concentrations and highest prevalence of viruses were found at the mouth of the inlet and offshore in the inlet plume. Results suggest that inlets moving large volumes of water into the coastal zone with tides may be an important source of fecal contaminants. Efforts to reduce run-off or unintended release of water into the Intracoastal Waterway may lower contaminants entering sensitive coastal areas.  相似文献   

10.
《Marine pollution bulletin》2014,78(1-2):118-129
There is a growing concern of seawater intrusion to freshwater aquifers due to groundwater overexploitation in the eastern coastal belt of Southern India. The problem becomes complex in the regions where industrial effluents are also contaminating the freshwater aquifers. In order to understand the hydrochemical complexity of the system, topographic elevation, static water level measurements, major ion chemistry, ionic cross plots, water type contours and factor analysis were applied for 144 groundwater samples of shallow and deep sources from Quaternary and Tertiary coastal aquifers, located within the industrial zone of 25 km2 area near Cuddalore, Southern India. The ionic cross plots indicates dissolution of halite minerals from marine sources and seawater mixing into inland aquifers up to the level of 9.3%. The factor analysis explains three significant factors totaling 86.3% of cumulative sample variance which includes varying contribution from marine, industrial effluent and freshwater sources.  相似文献   

11.
Sources of Enterococcus faecalis isolates from Pensacola Beach, FL. were identified using a library-based approach by applying the statistical method of average similarity to single and composite data sets generated from separate analyses. Data sets included antibiotic resistance analysis (ARA), rep-fingerprints, and fatty acid methyl ester (FAME) profiles. Use of a composite data set composed of ARA and rep-fingerprints, added to the confidence of the identifications. The addition of FAME data to composite data sets did not add to the confidence of identifications. Source identification was performed to better understand risk associated with higher densities of enterococci found in swash zone interstitial water (SZIW) as compared to adjacent bathing water on Pensacola Beach, FL. The "swash zone" is that area of the beach continually washed over by waves. As the potential sources of enterococci were limited in this environment, only two library units, sea gull and human, were constructed. Identification of the beach isolates using a composite data set indicated a sea gull origin. The clonality of the beach isolates suggested that the beach environment selects certain subspecies of E. faecalis.  相似文献   

12.
Caffeine in Boston Harbor seawater   总被引:1,自引:0,他引:1  
Caffeine has been detected in Boston Harbor seawater with concentrations ranging from 140 to 1600 ng l(-1), and in Massachusetts Bay seawater at concentrations from 5.2 to 71 ng l(-1). Sources of caffeine appear to be anthropogenic with higher concentrations in the seawater of Boston's inner harbor and in freshwater sources to the harbor. Charles River water and Deer Island sewage treatment plant effluent, the two major sources of freshwater to the harbor, contained 370 and 6700 ng l(-1) of caffeine, respectively, in 1998. Sewage influent and effluent concentrations appear to be consistent with consumption estimates of caffeinated beverages for the Boston area and total organic carbon removal targets for treated sewage. Caffeine was inversely correlated to salinity in a transect from the mouth of Boston Harbor to Stellwagen Basin, indicating it may be a useful chemical tracer of anthropogenic inputs to marine systems.  相似文献   

13.
Fecal indicator levels in nearshore waters of South Florida are routinely monitored to assess microbial contamination at recreational beaches. However, samples of sand from the surf zone and upper beach are not monitored which is surprising since sand may accumulate and harbor fecal-derived organisms. This study examined the prevalence of fecal indicator organisms in tidally-affected beach sand and in upper beach sand and compared these counts to levels in the water. Since indicator organisms were statistically elevated in sand relative to water, the study also considered the potential health risks associated with beach use and exposure to sand. Fecal coliforms, Escherichia coli, enterococci, somatic coliphages, and F(+)-specific coliphages were enumerated from sand and water at three South Florida beaches (Ft. Lauderdale Beach, Hollywood Beach, and Hobie Beach) over a 2-year period. Bacteria were consistently more concentrated in 100g samples of beach sand (2-23 fold in wet sand and 30-460 fold in dry sand) compared to 100ml samples of water. Somatic coliphages were commonly recovered from both sand and water while F(+)-specific coliphages were less commonly detected. Seeding experiments revealed that a single specimen of gull feces significantly influenced enterococci levels in some 3.1m(2) of beach sand. Examination of beach sand on a micro-spatial scale demonstrated that the variation in enterococci density over short distances was considerable. Results of multiple linear regression analysis showed that the physical and chemical parameters monitored in this study could only minimally account for the variation observed in indicator densities. A pilot epidemiological study was conducted to examine whether the length of exposure to beach water and sand could be correlated with health risk. Logistic regression analysis results provided preliminary evidence that time spent in the wet sand and time spent in the water were associated with a dose-dependent increase in gastrointestinal illness.  相似文献   

14.
This study evaluates the main sources of antropogenic Pb in one of the most industrialized centers of the southern Chilean coast (36 degrees S). Stable lead isotopes ((206)Pb/(207)Pb, (208)Pb/(207)Pb) were used to trace main Pb sources to coastal sediments, considering the suspended particulate matter (SPM) from marine (traps), continental (rivers) and industrial effluents, sediments and leaded gasoline samples. The atmospheric input was evaluated through natural collectors; i.e. Raqui-Tubul salt marsh. Results show that marine samples lie on a trend between industrial effluents ( approximately 1.16, 2.44) and natural sources (1.20, 2.50), not related to gasoline consumption. Salt marsh sediments show comparable isotopic composition to marine samples, suggesting the importance of the atmospheric input in the coastal sediments, not related to the leaded gasoline composition either. The continental input (1.18, 2.48) is highly influenced by precipitation, being difficult to separate both sources (atmosphere and continental runoff), showing also similar isotopic ratio to marine sediments. The signal of industrial emissions is masked with the introduction of Pb with higher isotopic ratios, compared to the values observed in the material collected from traps (SPM approximately 1.19, 2.48). The contribution of more radiogenic Pb by the upwelling is suggested.  相似文献   

15.
太湖流域非点源污染特征与控制   总被引:2,自引:1,他引:1  
李兆富  杨桂山 《湖泊科学》2004,16(Z1):83-88
太湖流域非点源污染已经相当严重,直接威胁太湖流域的水环境安全.本文综述了太湖流域非点源污染来源于:农业生产的化肥、农药污染;畜禽水产养殖污染;城市地表径流面源和道路线源污染;城镇、农村生活污水的非达标排放;大气的干湿沉降等.并分析了太湖流域非点源污染的影响因素以及时空分布特点,最后从控制非点源污染源和污染物输移过程提出控制和治理非点源污染的措施.  相似文献   

16.
Optical properties of colored dissolved organic matter (CDOM) were measured as a tracer of polluted waters in a Southern California surf-zone with consistently high levels of fecal indicator bacteria. Salinity, temperature, fecal coliform, absorbance (200-700nm) and fluorescence (lambda(excitation)=350nm; lambda(emission)=360-650nm) were measured in the creek and surf-zone during a dry and rain event. Fluorescence to absorption ratios for CDOM were used to distinguish water masses, with two distinct CDOM end-members identified as creek (flu/abs=8.7+/-0.8x10(4)) and coastal (flu/abs=2.2+/-0.3x10(4)). Waters containing the same CDOM end-member had highly variable bacterial levels during the dry event, suggesting intermittent sources of bacteria added to a uniform water source, consistent with marine birds. During the rain event, increased levels of the creek end-member and bacteria indicated a second bacteria source from runoff.  相似文献   

17.
Hydrogen peroxide concentrations [H(2)O(2)] have been measured over the last two decades in multiple studies in surface waters in coastal, estuarine and oceanic systems. Diurnal cycles consistent with a photochemical production process have frequently being observed, with [H(2)O(2)] increasing by two orders of magnitude over the course of the day, from low nM levels in the early morning to 10(2)nM in late afternoon. Production rates range from <10 for off-shore ocean waters to 20-60nMh(-1) for near-shore coastal and estuarine environments. Slow night-time loss rates (<10nMh(-1)) have been attributed to biological and particle mediated processes. Diurnal cycles have also frequently been observed in fecal indicator bacteria (FIB) levels in surf zone waters monitored for microbial water quality. Measured peak peroxide concentrations in surface coastal seawaters are too low to directly cause FIB mortality based on laboratory studies, but likely contribute to oxidative stress and diurnal cycling. Peroxide levels in the surf zone may be increased by additional peroxide production mechanisms such as deposition, sediments and stressed marine biota, further enhancing impacts on FIB in marine bathing waters.  相似文献   

18.
Antibiotic resistance in bacteria is a growing problem that is not only restricted to the clinical setting but also to other environments such as marine species that harbor antibiotic resistant bacteria and therefore may serve as reservoirs for antibiotic-resistance genetic determinants. The aim of this study was to evaluate antibiotic resistance phenotypes in enterococci isolated from fecal samples of gilthead seabream and the associated mechanisms of resistance. A collection of 118 samples were analyzed and 73 enterococci were recovered. The strains showed high percentages of resistance to erythromycin and tetracycline (58.9% and 17.8%, respectively). Lower level of resistance (<13%) was detected for quinupristin-dalfopristin, ampicillin, high-level-gentamicin, high-level-streptomycin, high-level-kanamycin, ciprofloxacin and chloramphenicol. The erm(B), tet(L) or tet(M), aac(6′)-aph(2″) and aph(3′)-IIIa genes were shown in isolates resistant to erythromycin, tetracycline, high-level gentamicin and high-level kanamycin, respectively. Antibiotic resistance in natural microbiota is becoming a concern of human and environmental health.  相似文献   

19.
Sediment from the sewage sludge dump site area in the New York Bight contains bacteria resistant to antibiotics and heavy metals. The purpose of this study was to determine if antibiotic resistance could be transferred from donor to recipient Escherichia coli strains inoculated into glass vessels containing sediment and seawater obtained near the dump site. Temperature was maintained at 10°C, the mean winter temperature of benthic water at the dump site. Transconjugants (recipients which inherit donor genes for tetracycline resistance) were isolated from the seawater and sediment within one hour after inoculation and were found in all subsequent sediment samples for one month. Donor and recipient E. coli remained viable in the sediment for at least one month. Our results indicate that sewage sludge polluted sediment may serve as an environment conducive to conjugal transfer of antibiotic resistance genes.  相似文献   

20.
The coastal water quality of Çanakkale Dardanelles (Turkey) was assessed based on bacteriological data and physical–chemical parameters. Total coliform (TC), fecal coliform (FC), and enterococci (ENT) bacteria along with physicochemical parameters were measured monthly up to a year at 12 different sampling sites located through both coastal lines of the strait. The fecal bacteria were abounded at several sampling sites such as B1, B3, G3, and G4 due to direct wastewater discharges and septic leakages or overloading. Storm water runoff and sediment resuspension were important pathways for the transport of coliform and ENT bacteria to the Dardanelles, as the region receives high precipitation and strong winds for most part of the year. The values of pH, temperature, and salinity were in typical ranges for the studied area. The microbiological and physicochemical data were correlated individually and in combination. The best fit correlations for bacterial data were attained between TC and FC or TC and ENT (R = 0.67 or ?0.68), while those for the combined data were obtained for TC with temperature (R = 0.94) and TC with salinity (R = ? 0.70).  相似文献   

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