Comparison of mussels and crustacean plankton to monitor heavy metal pollution

The ability of freshwater organisms (mussels — Unio pictorum L. and crustacean plankton —Cladocera and Copepoda species) to monitor heavy metal pollution was compared under field conditions, near the effluent discharge of a sewage water treatment plant at Lake Balaton (Hungary). The mussels were transferred from their less polluted habitat to the study area. The crustacean plankton was collected at this site The concentrations of Hg Cd Cr Cut Pb, Zn, and Fe were measured m the gills of the transplanted mussels as well as the natural zooplankton in the summer period, using the AAS method. Both mussel gills and the zooplankton showed periodically high Fe-, Zn-, and Cu-concentrations. An elevated level of Hg was only observed in mussels, while high Pb- and Cr-concentrations were found only in crustacean plankton. Accordingly the zooplankton seems a more suitable model for monitoring heavy metal pollution under these field conditions.     

Bat activity affected by sewage effluent in Irish rivers

Bat activity and benthic macroinvertebrates were sampled at nine paired sites, upstream and downstream from sewage effluent discharges into Irish rivers. Bat activity was measured using broadband acoustic detectors and macroinvertebrates by three 30-s standard benthic kick samples per site. Biological indices of water quality were significantly lower downstream from sewage outfalls, relative to upstream. The soprano pipistrelle (Pipistrellus pygmaeus) was significantly more active (as measured by bat passes per unit time) at downstream sites, while Daubenton’s bat (Myotis daubentonii) was less active. These results contrast with those of a similar study in England, where P. pygmaeus were less active, and Myotis spp. were more active downstream from sewage outfalls. We suggest that P. pygmaeus were more active downstream in our study because of a preference for preying on small orthocladiinid Chironomidae (non-biting midges), which were significantly more abundant downstream. M. daubentonii may prefer Trichoptera (caddis fly), which were significantly more abundant upstream. Organic pollution may then affect bats, but its effect appears to be more complex than previously implied. Implications of changing nutrient levels in freshwaters for populations of M. daubentonii and P. pygmaeus may be different from what is currently suggested in the literature.     

Application of tracer method for investigation of dilution and decay of petrochemical effluent discharged into big river

The investigation of dilution and decay of petrochemical effluent discharged into big river have been performed. The experimental work on effluent behavior was carried out in Vistula river (P?ock area, Poland). The purpose of studies was selection of optimal location of effluent outfall under criterion of efficient mixing and evaluation of contributions of dispersion and self-purification processes to decrease the effluent concentration in river water at early stage of transport. The tracer method was applied in order to obtain the actual and expected states of effluent dilution. The radioactive tracer was been used as a reference substance to obtain the decay rates of the following components of petrochemical effluent: chemical oxygen demand (COD), phenol and oil product. ⁸²Br in a form of KBr was used as radioactive tracer. Rhodamine and uranine were used as fluorescent dyes. The river reach of the length of 10725 m was subject of investigations. The series of nine tracer experiments was performed. The measurements of distribution of concentration of tracers and selected pollutants along the river width was performed at five measurement profiles marked out on the river reach under test. Two speed boats equipped with devices for detection of radioactive and fluorescent tracers were employed to carry out the tracer experiments and sampling the river water. The results obtained allow to select an optimal location of effluent outfall. The new location selected provides remarkable improvement of dillution pattern. Expected growth of dilution rate is 1.5 times which corresponds to reduction of maximal effluent concentration of 3.85 times at distance of 10725 m downstream of the outfall. Measured values of the decay rate of certain components of effluent discharged constitute he basis for procedure of prediction of impact of petrochemical effluent on receiving river water. The data concerning the dilution and decay rate of petrochemical effluent indicate the multiplex preponderance of the dispersion process over the self-purification in early stage of pollution transport in river.     

An evaluation of two bacteriophages as sewage tracers

Two bacteriophages — phage 80 of Staphylococcus aureus and a P2-like phage (?MWD 1) of Escherichia coli (H₂S + ) — were evaluated as sewage tracers. Background plaque concentrations on the S. aureus host were < 1100 mL^?1 in seven (raw and treated) effluents tested but, on E. coli (H₂S +), they ranged from < 1100 mL^?1 in oxidation pond effluents to 1.1 × 10³ 100 mL^?1 in primary treated meatworks effluent. Thus, phage 80 appears to be a suitable tracer for both raw and treated sewage but ?MWD 1 may only be suitable for use in secondary treated effluent. In frozen samples, concentrations of both tracer phages were reduced by 90% within 2 days, but decreased more slowly over the following 68 days to around 5% of the original (unfrozen) titre. In a field test, the two phages were used simultaneously to trace the movement of oxidation pond effluents down a river system. Timing of assay of frozen samples and the advantages and limitations of bacteriophages as sewage tracers are discussed.     

Use of 90SR in fish vertebrae as an effluent exposure tracer in PCB-contaminated channel catfish

Strontium-90 was measured in the vertebrae of channel catfish (Ictalurus punctatus) collected from an embayment and the adjoining river/reservoir in order to determine their exposure to the polychlorinated biphenyl (PCB) and ⁹⁰Sr-contaminated effluent entering the embayment from a point-source discharge. Concentrations of PCBs in the fish were measured and compared with the ⁹⁰Sr levels to assess the role of the effluent as a possible source of PCB contamination in catfish in the river and embayment. Catfish exposed to the elevated levels of ⁹⁰Sr in the embayment were found to migrate into uncontaminated areas of the river where they were available to anglers. The pattern of PCB contamination in catfish did not mirror that of ⁹⁰Sr hence, little of the PCB burden of the fish in the river could be traced to continuing PCB discharges to the embayment.     

Tiber River Quality in the Stretch of a Sewage Treatment Plant: Effects of River Water or Disinfectants to Daphnia and Structure of Benthic Macroinvertebrates Community

The evaluation of Tiber River quality, in a stretch including a sewage treatment plant, has been carried out by the contemporary evaluation of water effect on Daphnia and benthic macroinvertebrates community structure. To achieve a good status of a river water by the end of 2015, as provided in the Water Framework Directive (WFD) 2000/60/EC, is necessary to know the quality starting point. To this end, several endpoints are expected by the WFD, including Daphnia toxicity test and macroinvertebrate community analysis. River water sampling was conducted in the four seasons, from upstream to downstream a sewage treatment plant. I endpoint. At the outfall of the sewage treatment plant, river water showed very high acute toxicity to Daphnia only in summer; some toxic effect can be found also upstream in spring. Results at the outfall were consistent with the hypothesis that disinfectants, mainly used in summer to treat discharging waters, are responsible of river water acute toxicity: Daphnia tests with each disinfectant (NaClO, PAA, ClO₂) showed high toxicity. River waters were also utilized in Daphnia reproduction tests. Samples at the outfall (excluding the summer one, undoubtedly toxic) caused slight reduction in survival and fecundity. Disinfectants were also checked in reproduction tests. Still at NOEC_24h, they caused a significant toxicity on both death rate and reproduction. II endpoint. Macroinvertebrate benthic community composition was evaluated upstream and downstream the sewage treatment plant, on these data Extended Biotic Index (EBI), was determined to get a score as quality class. A reduction of water quality score was found downstream the plant, one season delayed (autumn) respect the acute test on Daphnia. Effect of disinfectant discharge, river dilution capability on a short spatial scale and use of different endpoints are discussed in term of river stretch quality.     

Assessing the Impact of Effluents from a Modern Wastewater Treatment Plant on Breakdown of Coarse Particulate Organic Matter and Benthic Macroinvertebrates in a Lowland River

Wastewater treatment plants (WWTP) with insufficient technologies for wastewater purification often cause a distinct nutrient pollution in the receiving streams. The increased concentrations of dissolved nutrients can severely disturb the ecological integrity of streams, which has been recently shown for basic ecosystem processes like mineralization of coarse particulate organic matter (CPOM). The present study investigated the impact of a modern WWTP (Zentralkläranlage Jena) on breakdown rates of CPOM exposed in net bags (1 mm mesh size) to the effluent of a large municipal WWTP and an upstream control site in the Saale River (Thuringia, Germany) from April to October 2005. Control and effluent site differed significantly in water chemistry with increased concentrations of dissolved organic carbon (DOC), ammonium, sulfate, and chloride at the effluent site, while the control site displayed higher concentrations of nitrate. However, breakdown rates of toothpickers and small twigs were not significantly different between the sites, whereas breakdown rate of leaf litter was significantly higher at the effluent site (k?=?0.0124 day^?1) than at the control site (k?=?0.0095 day^?1). Benthic invertebrate assemblages inhabiting the sandy stream bed at both sites were dominated by Chironomidae and Oligochaeta, typical inhabitants of fine sediments. Although the Shannon diversity of the benthic invertebrates was slightly higher at the effluent site (0.85) than at the control site (0.63), no significant difference could be detected. Bacterial numbers in water samples and surface biofilms on glass slides also displayed no significant differences between the two sites. This study showed that the effluents of a WWTP with modern technologies for wastewater purification did not directly affect breakdown rates of CPOM, bacteria numbers in epibenthic biofilms and the water column, and the community composition of sediment inhabiting aquatic macroinvertebrates in an effluent-receiving river with already increased concentrations of dissolved nutrients.     

Brain AChE activity studies in some fish species collected from a mercury contaminated estuary

In an attempt to investigate the impact of the discharge of Hg contaminated effluent from a chlor-alkali industry into the Rushikulya river estuary, brain AChE activity was measured in three fish species, S. sihama, A. nenga and S. argus, sampled from the contaminated water of the estuary. The residual Hg levels in the brain tissue of the fishes were also determined. The maximum brain residual Hg level, 0.702 ± 0.205 mg kg^?1 ww, was recorded in S. sihama. The inhibition of the AChE activity observed in that species was as much as 26.48% when compared to the normal enzyme activity. The levels of inhibition. observed in the other two fish species, A. nenga and S. argus, were also more than the 10% index level suggested. A significant negative correlation observed between the brain residual Hg levels and the AChE activity levels suggested the use of fish brain AChE measurement as a regular monitoring protocol in assessment of the pollution of aquatic systems by Hg.     

Apparent Rapid Loss of Endocrine Disruptors from Wetlands Used to Store Either Tertiary Treated Sewage Effluent or Stormwater Runoff

The disruption of endocrine systems due to environmental contaminants potentially impacts on the developmental, behavioural, regulatory and reproductive systems of animals. A major source of exposure of animals (terrestrial and aquatic) to endocrine-disrupting compounds is through contact with contaminated surface waters contaminated with sewage effluent and/or stormwater discharge. We studied the response to endocrine-disrupting compounds of Gambusia holbrooki mosquito fish resident of wetlands that were used for the storage of either treated sewage effluent or stormwater runoff. We found that fish from wetlands that received polluted waters directly from the source (treated sewage effluent or stormwater runoff) demonstrated a morphological response consistent with endocrine disruption. In contrast, fish in the second in the series of wetlands that housed treated sewage effluent did not show evidence of such response. However, those from the second in the series of stormwater receiving wetlands did display a morphological response, although it could be considered milder than was observed in fish from the first in this effluent stream. Fish were also smaller in the wetland that received sewage effluent directly from the sewage treatment plant than elsewhere. Although the differences were not statistically significant, the average size of fish in the first in the series of stormwater wetlands were also small and second only to those in the first sewage effluent wetland.     

An Integration of Water Physicochemistry,Algal Bioassays,Phytoplankton, and Zooplankton for Ecotoxicological Assessment in a Highly Polluted Lowland River

Results of different approaches potentially useful for the evaluation of water ambient quality were analysed and compared in a small temperate lowland river with mixed diffuse and multiple-point source pollution. The Reconquista River (Buenos Aires Province, Argentina), one of the most polluted watercourses of Latin America, receives agrochemicals as well as domestic and industrial (mostly untreated) effluents. Physical and chemical water variables were determined; unispecies algal bioassays (with Chlorella pyrenoidosa and Scenedesmus acutus) were carried out in laboratory; and density and structure of phyto- and zooplankton were analysed at three sites in four dates (representing a range of likely conditions in the river). A general scheme of association among plankton, bioassays and physical/chemical variables was elaborated, that helped to infer possible control factors in this multi-stressed system. Some empirical methods, but mainly mathematical ones including multivariate techniques (as PCA, cluster analysis), were applied for evaluation of samples. A preliminary selection of indices and attributes as potential indicators of the water river quality was made, and then applied for assay a tentative integrative ordination of samples. The relative best water quality was recorded when-where dissolved oxygen concentration, algal diversity and planktonic crustacean density were higher. The worst water quality corresponded to the lack of cladocerans and lowest crustacean density, and higher: organic and industrial pollution, major nutrients (ammonium and orthophosphates), BOD, hardness, conductivity, algal biomass in bioassays, phytoplankton density (>10 000 ind. mL^-1), dominance of a single algal species (>90%), and rotifer proportion in zooplankton (>85%).     

2004-2011年滹沱河忻州段水质变化及影响因素

[目的]研究2004—2011年滹沱河流域忻州段地表水水质的变化,并对影响水质变化的自然社会经济因素进行探讨。[方法]利用2004—2011年的水质监测数据和有关的自然社会经济统计数据,采用有机污染综合指数方法。[结果](1)滹沱河忻州段近8a的地表水水质变化可分为持续恶化和快速改善两个阶段,2007年是水质变化趋势的转折点,两个阶段有机污染综合指数(T值)分别为5.51和2.85。(2)自然因素方面,河道水量、降水量与水质均呈负相关,相关系数分别为0.675,0.532(p0.01)。河道水量、降水量对各河段水质改善作用有限。社会因素方面,水质恶化主要与工业废水排放量、施用化肥量、生活污水排放量、污水处理能力有关,相关系数分别为0.689(p0.01),0.633(p0.01),0.465(p0.05)和0.905(p0.01)。[结论]2009年后虽然生活污水超过了工业废水排放,但污水处理厂的达标运行使河段水质进一步改善,污水处率是今后该地区水质持续改善的前提保障。经济发展与城镇化并未给水质带来压力,而且经济发展已成为改善水质的积极动力。     

再生水短期灌溉对土壤-作物中重金属分布影响的试验研究

再生水是农业灌溉的重要水资源。该文在田间小区开展了为期4年的再生水灌溉试验，研究了重金属在土壤-作物系统中的转化与分布规律。结果表明：短期内重金属在土壤中的累积不明显，且土壤和作物籽粒中的重金属含量都远低于国家标准规定的允许值，再生水短期灌溉对土壤环境和作物均不会造成污染影响；同时，不同再生水灌溉水量条件下，土壤中重金属含量无显著差异，再生水灌溉带入土壤中的重金属量小于作物收获所带走的重金属量，带出量和带入量对土壤中重金属平衡的影响较小。     

THE SEASONAL CHANGES OF KERATINOLYTIC FUNGI IN SEDIMENTS OF CATALONIAN RIVERS (SPAIN)

The Catalonian river sediments were found to be rich in keratinolytic fungi. The keratinolytic fungal populations showed clear seasonal changes in the river sediments. The main factors ‘regulating’ these populations in such habitat were temperature, dissolved oxygen concentration, pH, ammonium, nitrates, total fungal number, BOD₅, water poisons (cyanides, detergents, phenols), salinity and, presumably, strong insolation associated with low water levels. The last was probably of special importance in the deterioration of the fungal populations in the spring/summer season. A toxic effect on keratinolytic fungi in sediments was observed.Chrysosporium keratinophilum was found to be most resistant to industrial contaminants and salinity. Therefore, this species could be used as an indicator of water pollution.     

Effects of Urban Sewage on Dissolved Oxygen,Dissolved Inorganic and Organic Carbon,and Electrical Conductivity of Small Streams along a Gradient of Urbanization in the Piracicaba River Basin

In Brazil most of the urban sewage is dumped without treatment into rivers. Because of this, it is extremely important to evaluate the consequences of organic matter rich sewage on the structure and functioning of river ecosystems. In this study we investigated the effects of urban sewage on the dissolved oxygen (O₂), dissolved inorganic (DIC) and organic carbon (DOC), and electrical conductivity (EC) in 10 small streams of the Piracicaba River basin, southeast region of Brazil. In the Piracicaba River basin, which is one of the most developed regions of the country, only 16% of the total sewage load generated is treated. These streams were classified into two groups, one with heavy influence of urban sewage and another with less influence. Both concentrations and seasonal variability were distinct between the two groups. The streams that received sewage effluent had a combination of low O₂ with high DIC, DOC, and EC. In the polluted streams, concentrations of dissolved carbon forms and EC were higher and O₂ concentration lower during the low water period. In the less polluted streams seasonal variations in concentrations were small. We also investigated the efficiency of a sewage treatment plant installed two years ago in the catchment of one of these streams. It was observed an increase in the O₂ concentration after the beginning of the treatment, and a decrease of DIC and DOC concentrations especially during the low water period. However, no significant change was observed in the EC, suggesting that the concentrations of major ions is still unaltered, and that a secondary treatment is necessary in order to reduce ion load into the stream.     

BOD and COD studies of synthetic and semisynthetic cutting fluids

It is estimated that between 20 400 and 23 850 × 10⁶ 1 of spoiled cutting fluids are discarded in the U.S. each year. Most undergo some form of biological waste treatment, yet there is little information regarding the effectiveness of such treatment on these fluids. In this study, sixteen commercially available synthetic and semisynthetic cutting fluid concentrates were tested for their susceptibility to biological degradation. The BOD5S of each compound was determined as an indication of biological oxidation potential. Inocula of both sewage and river origin were used, with statistically identical results. It was found that biological utilization ranged from 0 to 31% of the total oxygen demand, as measured by COD. Studies with triazine and morpholine preservatives showed no relationship between effectiveness of preservation and degradability.     

Recycling of water for irrigation: Persistence of enteroviruses in sewage effluent and natural waters receiving the effluent

A virological analyses of a sewage treatment plant which provided chlorinated, activated sludge treated sewage effluent to irrigate a complete two-year crop of sugarcane was made. The raw, the activated sludge treated and the chlorinated sewage effluent, as well as streams and a harbor receiving sewage effluents were concentrated by either the polymer two-phase, PE-60, Al(OH)₃, protamine sulfate, or cellulose membrane method and assayed for human enteric viruses. Viruses were recovered from 100% (11/11) of the raw sewages tested at concentrations ranging from 27 to 19 000 PFU l^?1 while 76% (13/17) of the activated sludge treated effluent was positive at concentrations ranging from 7 to 5222 PFU l^?1. After chlorination, 58% (31/53) of the samples was positive for virus at concentrations ranging from 2 to 750 PFU l^?1. Human enteroviruses were also isolated from shallow flowing streams at distances up to 3 mi (5 km) from the closest known sewage effluent discharge point and from a harbor approximately 0.5 mi (0.8 km) from the point of sewage discharge entering the harbor. The viruses most often isolated were echovirus 7, coxsackievirus B-4, B-5 and poliovirus 1, 2, and 3. These results indicate that although activated sludge treatment plus chlorination remove approximately 90% of the virus from the raw sewage, the final treated sewage effluent, which is normally discharged into a stream and in this experimental study to irrigate sugarcane, still contains a significant concentration of infectious viruses. Furthermore, the recovery of enteroviruses from waterways at points distant from the sewage treatment plants indicates that sewage-borne viruses persist in natural water environment. The significance of enteric viruses in waters accessible to the public and used for irrigation purposes remains to be determined.     

Biodegradability of Disinfectants in Surface Waters from Buenos Aires: Isolation of an Indigenous Strain Able to Degrade and Detoxify Benzalkonium Chloride

Biodegradability of chlorhexidine (CH), triclosan (TC), and benzalkonium chloride (CBA) has been tested in 18 surface water sampling points in the urban area of Buenos Aires. Sampling points were located in both the Reconquista and the Matanza-Riachuelo basins as well as in the La Plata River. High tolerance to the three disinfectants was found and indigenous strains capable of degrading CBA and TC were isolated. Neither tolerance nor biodegradation were correlated with sewage pollution. A strain that degrades CBA was identified as belonging to the genus Pseudomonas using the API20NE system and 16SRNA sequencing. In batch assays, the strain was capable of degrading 100, 200, and up to 500 mg L^?1 of CBA in 10, 25, and 46 h respectively with specific growth rates (μ) of 0.56, 0.30, and 0.14 h^?1. The efficiency of the process was between 99.5–98.0% in terms of compound removal and between 93.8–89.1% in terms of chemical oxygen demand (COD). The detoxification of the compound as a result of the biodegradation was assessed using Pseudokirchneriella subcapitata, Vibrio fischeri, and Lactuca sativa as test organisms.     

Analysis of the distribution of some polycyclic aromatic hydrocarbons in sediments and suspended matter in the River Seine (France)

Sixteen EPA chosen polycyclic aromatic hydrocarbons (PAH) were studied in the sediments and the suspended matter of the River Seine to determine existing pollution. Analyses were carried out by HPLC with coupled fluorimetric and UV detectors. PAH contents were found to be highly variable depending on many factors such as anthropogenic activities, weather and flow rate of the river, and occasionally they rose to alarming levels. Contents of 16 PAH ranged from 1.5 to 7.4 μg g^?1 in the sediments, but a peak at 60.7 μg g^?1. In the suspended matter the contents were usually below 10 μg g^?1. From these results and taking into account the mean content of suspended matter in the river downstream from Paris, the total adsorbed PAH concentration in the river Seine should be about 60 ng l^?1. Evidence has been established that storm drain discharges are a major source of pollution.     

微核技术在新立河水质污染监测中的应用

为了解滨城区新立河水质的污染状况,选取水库出水闸、西谢庄桥、黄河2路桥、黄河5路桥、黄河8路桥、黄河12路桥、黄河15路桥及北外环路桥8个河段处为取样点,利用蚕豆根尖细胞微核技术对各采样点进行了生物监测。调查了各河段样点的排污口数及水质表观特征,综合评价了新立河水质的污染情况。结果表明,在污染最严重的黄河5路桥至黄河15桥河段污染指数均3.50,该河段污染来源主要来自生活污水及工业废水,排污口数达调查河段的58.54%。排放污水为黑色,带有明显恶臭。利用蚕豆根尖细胞微核技术监测结果与现场调查的水质表观污染状况基本吻合。综合分析表明,新立河水质污染较严重,且有导致生物染色体分裂异常现象,需加大力度进行治理。