Municipal Sewage Effluent Research Articles

A survey of endocrine disrupting chemicals (EDCs) in municipal sewage and animal waste effluents in the Waikato region of New Zealand

We report the results of a recent survey of the concentration of natural estrogens (17β-estradiol, 17α-estradiol, estrone, estriol) and the synthetic estrogen, 17α-ethynylestradiol in representative animal wastes and sewage treatment plant (STP) effluents in the Waikato region of New Zealand. Dairy farm effluent samples showed high levels of estradiol (19–1360 ng/L) and its breakdown product estrone (41–3123 ng/L) compared with piggery or goat farm effluents. The combined load for these estrogens (excluding β epimer) varied from 60 to > 4000 ng/L. The piggery effluent provided the lowest total estrogen load (46 ng/L), with estrone accounting for nearly 60% of the measured estrogens in this sample. The synthetic analogue, 17α-ethynylestradiol was detected only in one wastewater treatment plant sample, albeit at trace level. An estrogen receptor competitive binding assay was used to test the biological activity of the samples and confirmed that most agricultural waste samples contain high levels of estrogenic compounds. The potential of these wastes to cause endocrine disruption in the receiving ecosystem is unknown at present.

Comparative study of the estrogenic responses of mirror carp ( Cyprinus carpio) exposed to treated municipal sewage effluent (Lisbon) during two periods in different seasons

To assess the estrogenic potency of the treated domestic sewage effluent from a sewage treatment plant (STP) located in Lisbon (Chelas), 60 mirror carp ( Cyprinus carpio) were exposed to different concentrations of the sewage effluent (0%, 25%, 50% and 100%) for two periods of 28 days in two different seasons (winter/spring). Vitellogenin induction in males was used as a biomarker of exposure to xenoestrogens. At the end of the experiment, blood samples were taken for vitellogenin analysis and the fish were sacrificed and dissected. Gonad samples were taken for histological evaluation of the sewage effects. The results showed an increase in vitellogenin induction in exposed fish, both males and females, depending on the different dilutions of the sewage effluent. In comparison with controls, the gonadosomatic index decreased significantly ( P<0.05) in fish exposed to 100% treated effluent. Although statistically not significant, the hepatosomatic index (HSI) was high in all exposed fish. Histological abnormalities in fish gonads were evaluated and related to the different percentages of sewage effluent. Seasonal variations found in estrogenic responses were attributed to weather influences on sewage dilution.

Urban diffuse sources of faecal indicators

Increasing concern about bathing water quality in Scotland has led to renewed interest in diffuse sources, as well as the already closely monitored municipal sewage effluents and combined sewer overflows (CSOs) that have been the subject of multi-million pound capital expenditure schemes for several years. Early investigations of diffuse sources focused on rural land uses. This paper is an initial effort to consider the possible significance of urban diffuse sources. A review of the potential for diffuse urban sources includes consideration of sewage pollution in surface water sewers, as well as non-human sources such as pigeon and other bird roosts, and faecal material from pets such as dogs and cats. Portobello beach in Edinburgh is the case study selected, because of earlier work done by Scottish Water and SEPA. The Figgate Burn crosses Edinburgh to discharge onto the beach at Portabello, and pollution sources in its catchment are described. Additional information is reported from Dunfermline, where the sewer network has provided examples of three ways in which sewage pollution can occur in urban streams, and also Scottish examples of measures to control some non-human sources (e.g. SUDS).

Effects of treated sewage effluent on immune function in rainbow trout ( Oncorhynchus mykiss)

In this study, the immune reactions of rainbow trout ( Oncorhynchus mykiss) were examined, after exposure to 10, 30 and 70% of tertiary-treated municipal sewage effluent for 27 days. Exposures were conducted concurrently with and without an immune challenge using intraperitoneal injections of inactivated Aeromonas salmonicida salmonicida. Due to the time required to prepare and analyse samples, fish sampling was conducted over two consecutive days. There was no trout mortality for any of the experimental treatments. The exposure to effluent increased in vitro lymphocyte proliferation, decreased circulating lymphocytes and increased degrading erythrocytes in peripheral blood samples. Circulating lymphocytes were only decreased in the sham-injected, but not in the A. salmonicida-injected group. In addition to effluent effects, circulating lymphocytes and lymphocyte proliferation were decreased on day 2 of sampling as compared to day 1. Concentration-dependent degradation of erythrocytes was only observed on day 2 of sampling. Capture and removal of trout on day 1 of sampling presumably caused low-level stress that affected some results on day 2. Oxidative burst, phagocytosis, lysozyme, leucocyte populations other than lymphocytes and A. salmonicida-specific IgM production were not affected by exposure to effluent, and of these parameters, only oxidative burst and total leucocytes showed sampling day effects. From these results it can be observed, that with the exception of oxidative burst, those variables affected by effluent exposure were also significantly changed by the low-level sampling stress imposed by staggered sampling. Elevated liver mixed-function oxygenase activity as measured by 7-ethoxyresorufin- O-deethylase activity, and increased bile polycyclic aromatic hydrocarbon (PAH) metabolites were observed in response to sewage effluent exposure. As both PAHs and stress are known immune suppressors, it is difficult to conclude whether or not changes in immune parameters due to effluent exposure were caused by the direct action of chemicals, or were due to a general stress response.

Geochronology of anthropogenic pollutants in riparian wetland sediments of the Lippe River (Germany)

Anthropogenic pollutants were determined in a dated sediment core, collected from a riparian wetland of the Lippe River (Ruhr district, Germany). The historical trend in heavy metals, polycyclic aromatic hydrocarbons, organochlorines, polychlorinated biphenyls and linear alkylbenzenes as well as more recent contaminants such as industrial additives, organotins, synthetic musks, methyltriclosan and some other compounds were determined for the time period between 1930 and 1986. Emission sources, information on technical production and usage, as well as on the individual pollution pathways, with appropriate environmental stability, were considered in the interpretation of the sediment contamination over the past ∼50 years. Contaminants were analysed and interpreted according to two different criteria: (a) the origin of the main contaminants as related to mining and industrial activities as well as municipal sewage and agricultural effluents and (b) the pollution history. Due to a significant appearance of formerly missing contaminants in sediments deposited since 1970, we suggest classifying contaminants as either common (predating 1970) or modern (postdating 1970). In summary, the study provided a comprehensive reconstruction of the pollution history of the Lippe River system.

Geochronology of anthropogenic pollutants in riparian wetland sediments of the Lippe River (Germany)

Anthropogenic pollutants were determined in a dated sediment core, collected from a riparian wetland of the Lippe River (Ruhr district, Germany). The historical trend in heavy metals, polycyclic aromatic hydrocarbons, organochlorines, polychlorinated biphenyls and linear alkylbenzenes as well as more recent contaminants such as industrial additives, organotins, synthetic musks, methyltriclosan and some other compounds were determined for the time period between 1930 and 1986. Emission sources, information on technical production and usage, as well as on the individual pollution pathways, with appropriate environmental stability, were considered in the interpretation of the sediment contamination over the past ∼50 years. Contaminants were analysed and interpreted according to two different criteria: (a) the origin of the main contaminants as related to mining and industrial activities as well as municipal sewage and agricultural effluents and (b) the pollution history. Due to a significant appearance of formerly missing contaminants in sediments deposited since 1970, we suggest classifying contaminants as either common (predating 1970) or modern (postdating 1970). In summary, the study provided a comprehensive reconstruction of the pollution history of the Lippe River system.

Partitioning of polycyclic aromatic hydrocarbons between water and particles compared to bioaccumulation in mussels: a harbour case.

Water and particles from three sites located in Halifax Harbour, near and further away from combined municipal sewage effluents (CMSE) were analysed for parental and alkylated polycyclic aromatic hydrocarbons (par and alkPAH). Bioavailability of PAH was compared for inter-tidal mussels collected at the same sites in April and November. The PAH fingerprint determined over 9 sampling times covering a period of 19 months differed more between phases (water and particles) and seasons, than between sites. In the spring, more alkPAH associated with diesel and gasoline were detected in the soluble phase, along with more bioaccumulation of alkPAH in inter-tidal mussels. A broader number of parPAH were detected in mussels collected in the fall. The mean sum of dissolved alkPAH concentrations was higher in water at the site closer to raw CMSE than at the other two sites and particles of that site. However, lowest bioconcentration factors (BCF) were determined in mussels of this more contaminated site. Similar biota-particle accumulation factors (BPAF) were determined for parPAH in mussels from the three sites, all lower than the BCF of alkPAH. The study indicates that sewage treatment plants will reduce the amount of parPAH especially larger than fluoranthene and pyrene from being deposited in the harbour; that alk naphthalenes and fluorenes present in water will continue to be discharged; that the disturbance of sediments can make particle-bound PAH available to mussels.

Estrogenicity in bile of juvenile rainbow trout as measure of exposure and potential effects of endocrine disruptors.

Estrogenicity in the bile of juvenile rainbow trout exposed to effluents from municipal sewage treatment plants and various industries was assayed by using a recombinant yeast strain containing the human estrogen receptor alpha gene. Estrogenicity in bile also was measured after deconjugation of steroids to provide an estimate of the exposure and as an endpoint for potential effects on the organism. In unexposed fish or fish exposed for three weeks at control localities, 0.5 to 9 ng of estradiol equivalents (EEq) were found per gram of bile (ng EEq/g bile). Fish exposed for three weeks in cages placed in the receiving waters near outlets of municipal effluent had an average activity of 26 ng EEq/g bile. Fish exposed to undiluted sewage water in aquaria had a bile estrogenicity of 51 to 87,000 ng EEq/g bile. Unconjugated estrogens contributed only 8% or less to the estrogenicity in bile of fish exposed to municipal effluents. Municipal sewage effluents were more estrogenic than the industrial effluents that were investigated. Estrogenicity in bile was compared to that in extracts of wastewater by using the same receptor assay, and to vitellogenin induction in the plasma of the same fish. Bile estrogenicity proved to be a useful and sensitive (internal) measure of exposure and indicated its potential for the display of biological effects as a complement or replacement of more laborious assays.

Field Studies on the Fate and Transport of Pharmaceutical Residues in Bank Filtration

AbstractBank filtration and artificial ground water recharge are important, effective, and cheap techniques for surface water treatment and removal of microbes, as well as inorganic, and some organic, contaminants. Nevertheless, physical, chemical, and biological processes of the removal of impurities are not understood sufficiently. A research project titled Natural and Artificial Systems for Recharge and Infiltration attempts to provide more clarity in the processes affecting the removal of these contaminants. The project focuses on the fate and transport of selected emerging contaminants during bank filtration at two transects in Berlin, Germany. Several detections of pharmaceutically active compounds (PhACs) in ground water samples from bank filtration sites in Germany led to furthering research on the removal of these compounds during bank filtration. In this study, six PhACs including the analgesic drugs diclofenac and propyphenazone, the antiepileptic drugs carbamazepine and primidone, and the drug metabolites clofibric acid and 1‐acetyl‐1‐methyl‐2‐dimethyl‐oxamoyl‐2‐phenylhydrazide were found to leach from the contaminated streams and lakes into the ground water. These compounds were also detected at low concentrations in receiving public supply wells. Bank filtration either decreased the concentrations by dilution (e.g., for carbamazepine and primidone) and partial removal (e.g., for diclofenac), or totally removed PhACs (e.g., bezafibrate, indomethacine, antibiotics, and estrogens). Several PhACs, such as carbamazepine and especially primidone, were readily transported during bank filtration. They are thought to be good indicators for evaluating whether surface water is impacted by contamination from municipal sewage effluent or whether contamination associated with sewage effluent can be transported into ground water at ground water recharge sites.

Oxidative stress responses in longnose sucker ( Catostomus catostomus) exposed to pulp and paper mill and municipal sewage effluents

While recent evidence indicates that the generation of reactive oxygen species (ROS) and associated oxidative damage are frequently observed in fish populations with exposure to pulp and paper mill effluents, the potential for ROS generation from municipal sewage effluents has not been addressed. This study investigates the utility of measures of oxidative stress in delineating the effects of both pulp and paper mill and municipal sewage discharges. Longnose sucker ( Catostomus catostomus) were collected below three pulp and paper mill and two municipal sewage effluent discharges over a 3-year period within the Wapiti and Athabasca River systems in northern Alberta. Biochemical responses in longnose sucker varied between the two rivers systems, with more pronounced changes occurring within the Wapiti River. Of the suite of biochemical parameters examined, fatty acyl-CoA oxidase (FAO) activity was the most sensitive indicator of pulp and paper mill exposure, but was only infrequently induced with exposure to municipal sewage effluent. Hepatic and gonadal 2-thiobarbituric acid reactive substances, lipid hydroperoxides, and hepatic free iron were less consistently elevated with exposure to pulp and paper mill effluent than FAO activity, and were also only infrequently altered with sewage effluent exposure. Hepatic ascorbic acid, liver somatic index, and condition factor were consistently altered with exposure to both sewage and pulp and paper mill effluents. While specific biochemical and organismal responses varied with effluents and time, the collective suite of oxidative stress endpoints proved to be useful tools in identifying relative influences of municipal sewage and pulp and paper mill effluent on fish populations in adjacent receiving waters.

The effects of dissolved organic matter on the decomposition of di-n-butyl phthalate by ozone/hydrogen peroxide process

The effects of the dissolved organic matter (DOM) on the ozone decay and the di-n-butyl phthalate (DBP) decomposition during ozone/hydrogen peroxide (O3/H2O2) process were investigated (DBP-d4 was used instead of DBP). Four surface waters, two secondary municipal sewage effluents (SMSEfs) and Suwannee river natural organic matter were used as DOM. The ozone decompositions in the DOM solutions were separated by instantaneous ozone consumption and slower ozone decay. The effect of H2O2 addition on the ozone decay was clearly observed at slower ozone decay. Ozone decomposition rate at slower ozone decay increased linearly with H2O2 dose. DBP-d4 was exponentially decreased with ozone consumption. Ozone consumption required to decompose 90% of DBP-d4 ((deltaO3)90%) in SMSEFs was higher than those in surface waters. The (deltaO3)90% per DOC of DOM values were from 22 to 23 micromole/mgC for SMSEFs and from 10 to 17 micromole/mgC for surface waters. The (deltaO3)90% values were correlated to specific ultraviolet absorbance at 254 nm (SUVA254) for surface waters.

Occurrence and Some Properties of the Androgenic Activity in Municipal Sewage Effluents

Androgenicity was tested in municipal effluents before and after treatment in sewage treatment plants using different treatment methods. The activity was tested with a recombinant yeast strain transfected with the gene for the human androgen receptor. Fractionation of effluents showed some basic properties of compounds with androgenic activity. Effluents from Swedish domestic sewage treatment plants contained compounds with androgenic effects. Levels varied from 0–160 ng dihydrotestosterone (DHT) equivalents/L. The androgenicity was higher in untreated effluents and removals of 26 and 42% for STWs without secondary treatment and 96– > 99% were recorded for STWs with secondary and tertiary treatment. As with estrogens in municipal effluents, STWs using biological treatment such as activated sludge and solid supported microbial processes were more effective in reduction of androgenic activity. Plants using only precipitation methods removed less of the activity. The androgens were composed of at least three individual compounds, similarly or less lipophilic than DHT.

Treated sewage effluent (water) potential to be used for horticultural production in Botswana

Botswana being semi-arid and arid country, the provision of drinking water and water for agricultural production is becoming increasingly scarce and expensive. Measures that can augment the available sources of water or measures that can reduce the demand on potable water should be given serious consideration. Horticulturists have incorporated new technology into many of their production programs, which has enabled them to grow more horticultural crops with less water; however, more effort is needed. Techniques such as drip irrigation, sensors, growing plants with low water requirements, timing and scheduling of irrigation to the growth needs of the plant, mulching, and establishing a minimum water quality standard for horticultural crops must be used to stretch agricultural water supplies. Recycling agricultural water and using treated municipal sewage effluent is a viable option for increasing horticultures’ future water supply in Botswana. Agriculture wastewater and sewage effluents often contain significant quantities of heavy metals and other substances that may be toxic to people but beneficial to horticultural crops. However, before sewage effluent can be used for commercial production of vegetables and fruits, research must be undertaken to determine whether there is accumulation of heavy metals and faecal coliforms in the edible portion of the horticultural produce which may be detrimental to human health 15–20 years later. Research must be undertaken to assess the impact of sewage effluent on soil physical, chemical properties and environment after continued use.

Evaluation of an on-line coupled continuous flow liquid membrane extraction and precolumn system as trace enrichment technique by liquid chromatographic determination of bisphenol A

An on-line coupled continuous flow liquid membrane extraction (CFLME) and C 18 precolumn system was developed for sample preconcentration in liquid chromatography determination. After preconcentration by CFLME, which is based on the combination of continuous flow liquid–liquid extraction and supported liquid membrane, bisphenol A (BPA) was enriched in 960 μl of 1 mol l −1 NaOH used as acceptor. This acceptor was on-line neutralized and transported onto the C 18 precolumn where analytes were absorbed and focused. Then the focused analytes were injected onto a C 18 analytical column for separation and detected at 220 nm with a diode array detector. CFLME related parameters such as flow rates, pH of donor and acceptor, and enrichment time were optimized. The proposed method presents a detection limit of 0.03 μg l −1 ( S/ N=3) when 60 ml samples was enriched with an enrichment time of 30 min. Compared with C 18 based column-switching procedure, this proposed procedure presents similar sample throughput and lower detection limits. The proposed method was successfully applied to determine BPA in tap water, river water, and municipal sewage effluent samples.

Treated municipal sewage discharge affects multiple levels of biological organization in fish

The objectives of this study were to examine cellular-, organ-, and organism-level responses in longear sunfish ( Lepomis megalotis) and fish community structure in a stream in which treated municipal sewage effluent is discharged and in a nearby reference stream with little surrounding land use. A modified version of the U.S.E.P.A. Rapid Bioassessment Protocol V, which combines a habitat assessment with Karr's index of biotic integrity, was used on 400-m reaches of each stream. The study site had a higher proportion of tolerant species and omnivores and a lower proportion of top predators, suggesting alterations in the fish community and a slight level of water quality impairment. Significant increases in condition factor, hepatosomatic index, serum testosterone, and plasma vitellogenin concentrations were observed in male sunfish collected from the study stream in comparison to fish collected from the reference stream. There were no differences between sites in hepatic expression of the 70-kDa stress protein (HSP70). In conclusion, effects were observed at cellular, organ, organism, and community levels of biological organization in fishes exposed to treated municipal sewage effluent.

Occurrence, Fate, and Assessment of Polycyclic Musk Residues in the Aquatic Environment of Urban Areas — A Review

AbstractIn recent years, polycyclic musk compounds frequently used as synthetic fragrances in perfumes and various household products have been recognized as important organic residues in the aquatic environment, especially, in urbanized areas. These persistent contaminants are primarily discharged via municipal sewage effluents into the receiving surface waters. In some investigations of samples from different environmental compartments, 1, 3, 4, 6, 7, 8‐hexahydro‐4, 6, 6, 7, 8, 8‐hexamethylcyclopenta‐(g)‐2‐benzopyran (HHCB; Galaxolide®, Abbalide®) and 7‐acetyl‐1, 1, 3, 4, 4, 6‐hexamethyltetralin (AHTN; Tonalide®, Fixolide®) were identified as the most important synthetic musk compound residues. In Europe, all of the other synthetic musks, including the nitro musk compounds, were only found at trace‐level concentrations more than 20 times lower than those measured for HHCB.This paper compiles and discusses the results from investigations of sewage, sewage sludge, surface water, aquatic sediment, and biota samples. The results from several prolonged monitoring investigations of musk residues in Berlin, Germany, are presented as an example for the occurrence and fate of polycyclic musks in the aquatic system of an urbanized area. Significant differences were observed for the concentration ratios of HHCB and AHTN in samples originating from different aquatic compartments. Thus, an average HHCB/AHTN ratio of approximately 2.5:1.0 was measured in sewage sludges, sewage effluents, surface waters, and fish. In sediment samples, AHTN was, however, found at concentrations equal or even higher than those measured for HHCB (HHCB/AHTN ratio of 0.90:1.0). Bioaccumulation, metabolism in fish, and environmental and human risk assessment issues are discussed and results obtained for the urban area of Berlin are compared with those from other investigations.

On-site solid-phase extraction and laboratory analysis of ultra-trace synthetic musks in municipal sewage effluent using gas chromatography–mass spectrometry in the full-scan mode

Fragrance materials such as synthetic musks in aqueous samples, are normally determined by gas chromatography–mass spectrometry in the selected ion monitoring (SIM) mode to provide maximum sensitivity after liquid–liquid extraction of 1-l samples. Full-scan mass spectra are required to verify that a target analyte has been found by comparison with the mass spectra of fragrance compounds in the National Institute of Standards and Technology (NIST) mass spectral library. A 1-l sample usually provides insufficient analyte for full scan data acquisition. This paper describes an on-site extraction method developed at the US Environmental Protection Agency (Las Vegas, NV, USA) for synthetic musks from 60 l of wastewater effluent. Such a large sample volume permits high-quality, full-scan mass spectra to be obtained for a wide array of synthetic musks. Quantification of these compounds was achieved from the full-scan data directly, without the need to acquire SIM data. The detection limits obtained with this method are an order of magnitude lower than those obtained from liquid–liquid and other solid-phase extraction methods. This method is highly reproducible, and recoveries ranged from 80 to 97% in spiked sewage treatment plant effluent. The high rate of sorbent-sample mass transfer eliminated the need for a methanolic activation step, which reduced extraction time, labor, and solvent use. More samples could be extracted in the field at lower cost. After sample extraction, the light-mass cartridges are easily transported and stored.

Nutrient release and sediment oxygen demand in a eutrophic land-locked embayment in Hong Kong

Tolo Harbour is a large eutrophic land-locked estuarine embayment in Hong Kong. The rapid urbanization, commercio-industrial activities and lack of legislative control around the Tolo catchment produced large quantities of untreated or partially treated municipal sewage, agricultural wastes and cottage industrial effluents which were discharged into Tolo Harbour via rivers and watercourses. Control measures were implemented to reduce the external nutrient loading into the harbour since the early 1980s. Nutrient data for the period 1982 to 1997 were analyzed for temporal trends. Over the period of observation, the total inorganic nitrogen and total phosphorus both show an increasing trend, despite a decade of efforts in reducing nutrient loading. The release rates of potentially mobile nitrogen (N) and phosphorus (P) from the sediments collected from Tolo Harbour were determined by N and P release experiments under oxic conditions. The experimental results showed that the sediment released significant amount of nutrients, especially orthophosphates and ammonia nitrogen. The maximum release rates were 15.0 and 206.0 mg/m 2/day, respectively. Although the external nutrient loading has been reduced, nutrients could gradually be released back into the water column from the contaminated sediments and delay improvement of the water quality.

Salmonellain sewage effluent raises ecological and food-safety concerns

Salmonella bacteria continue to be an important public-health problem and have a serious economic impact on the U.S. poultry industry. Although the majority of human infections traceable to Salmonella enteritidis are related to egg consumption, this serotype has also been isolated from a variety of nonegg food items such as meat, vegetables and fish. In Southern California, S. enteritidis phage type 4 infection is the predominant serotype found in human patients. However, the organism has also been found in municipal sewage effluent and in rodent and poultry environments. S. enteritidis phage type 4 was first detected in human patients in Southern California in 1990, but wasn't isolated from food-producing animals until its occurrence at a Southern California egg-layer ranch in 1994. An epidemiological study revealed that the layer flock was infected via effluent originating from a nearby municipal sewage-treatment plant. Human sewage effluent was the primary environmental source, combined with wildlife that further amplified and disseminated the bacteria. This discovery has important implications for understanding the ecology of S. enteritidis infection in poultry and humans and developing appropriate methods to prevent its further spread.

Trophic Conditions and Stoichiometric Nutrient Balance in Subtropical Waters Influenced by Municipal Sewage Effluents in Mazatlán Bay (SE Gulf of California)

This work presents results of a study carried out between February 1995 and August 1996, on the trophic state of coastal waters influenced by a sewage outfall in Mazatlán Bay. Dissolved nutrients (ammonia, nitrate, nitrite, total inorganic nitrogen, reactive silicate and inorganic phosphate) and phytoplankton were used as parameters. The relative abundance by phytoplanktonic group changed in the different sites, in some sites (monthly sampled) bacillariophyte was the best-represented group with abundance ca. 70%. In additional sites around outfall and where red tides blooms occurred, this group was lower representation on the phytoplanktonic community. The application of two trophic indices based on nutrient concentrations corroborated along with the Shannon–Wiener diversity index indicates that Mazatlán Bay can be regarded as a predominantly eutrophic system. Additionally, the stoichiometric balance criterion in all selected sites confirmed that the mean ratio for the nutrients calculated does not reach the Redfield ratio Si:N:P of 16:16:1.