Sewage Treatment Works Effluent Research Articles

Linear alkylbenzene sulfonate and boron monitoring in four catchments in the UK contribution to GREAT-ER #11

A comprehensive monitoring programme was carried out in the Aire, Calder, Went and Rother catchments in the UK. A total of 804 effluent samples from 36 sewage treatment works (STWs) and 1100 water samples from 54 river sampling sites were analysed. Concentrations of linear alkylbenzene sulfonate (LAS), boron and other water quality determinands in STW effluent and river waters over a 2-year period (August 1996–August 1998) are reported. The data illustrate the temporal and spatial variations in concentrations of LAS and boron in river waters and effluents. Concentrations of LAS in effluents reflect the biological treatment employed and the influence of tertiary treatment is clearly demonstrated.

Steroid estrogens profiles along river stretches arising from sewage treatment works discharges.

Concentrations of estradiol, estrone, and ethinylestradiol were measured in the water column (daily for 28 or 14 days) and in the bed sediment (weekly over the same period) of the River Nene and the River Lea, U.K., upstream and downstream of sewage treatment works (STW). The concentrations of the three steroids in the STW effluents were also measured. Estrone was detected at the highest concentration and in almost all samples from the three STW effluents, concentrations ranging from <0.4 to 12.2 ng/L. Estradiol was also detected frequently (<0.4-4.3 ng/L), but ethinylestradiol was detected infrequently (<0.4-3.4 ng/L). Positive detections were only found for estrone in the sediment, and these seemed to be unrelated to the water column concentrations. Levels of estrone were clearly raised above background levels in the rivers as a result of the STW discharges. Levels of estradiol and ethinylestradiol were too close to their detection limits to assess the STW impact. River water estrone concentration declined downstream at a rate that was in excess of that due to dilution. The most likely cause of this decline is a combination of sorption and biodegradation equivalent to a first-order decay half-life of 2.5 days for the River Nene and 0.5 days for the River Lea.

Estrogenic activity measured in a sewage treatment works treating industrial inputs containing high concentrations of alkylphenolic compounds—A case study

Chemical analyses were combined with a biological assay to investigate the main estrogenic chemicals as they passed through a sewage treatment works (STW) and entered a river. The STW studied was unusual in that it received wastewater from the textile trade. This wastewater was shown to contain high concentrations of alkylphenol polyethoxylates and their degradation products, such as nonylphenol. High-performance liquid chromatography fractionation, combined with biological assay, showed that the majority of the estrogenic activity was contributed by the alkylphenolic chemicals and the natural estrogens 17beta-estradiol and estrone. Despite removal of a high proportion of the alkylphenolic chemicals by the various treatment processes within the STW, concentrations in the final effluent were still high compared to most other STW effluents in the United Kingdom. The effluent was very estrogenic to caged fish, as was the river water 2 and 5 km downstream of the STW, even though less so. Using various approaches, attempts were made to determine which group of chemicals contributed most to the estrogenic activity of the effluent. The analysis suggested that, in this unusual situation, the alkylphenolic chemicals may contribute the majority of the estrogenic activity of the effluent. However, this conclusion was based on a number of uncertainties that are presently unresolved and hence can be considered only tentative.

Binding of Waterborne Steroid Estrogens to Solid Phases in River and Estuarine Systems

Natural and synthetic steroid estrogens have been detected in sewage treatment work effluents discharged into rivers. An understanding of the partitioning of these estrogens between water and sediment is critical for the prediction of their fates in river systems. Hence, a series of experiments was conducted to ascertain the effects of differing environmental conditions on estrogen partitioning to sediment. Fugacity level 1 (sediment phase) output data demonstrated a good correlation with removal of estrogens from the water phase. Synthetic estrogens, with their higher Kow values, were removed more readily from the water phase than the natural estrogens. Maximum sorption to the sediment phase was attained after 1 h of shaking. At higher estrogen concentrations, there was a decrease in estrogen removal, while higher levels of sediment induced greater removal. The sorption of estrogen to sediments correlated with total organic carbon content. However, the presence of organic carbon was not a prerequisite fo...

Long-Term Temporal Changes in the Estrogenic Composition of Treated Sewage Effluent and Its Biological Effects on Fish

Sewage treatment works (STW) effluents throughout the U.K. have been shown to be estrogenic, inducing vitellogenin (VTG) synthesis in caged and wild fish for considerable distances (up to several kilometers) downstream of the effluent discharge. Thresholds for vitellogenin induction in caged fish in those studies have been derived from short-term exposures, and may not necessarily be representative of thresholds for estrogenic responses in wild fish living in rivers that contain STW effluent. In addition, very little is known about the long-term fluctuations in the concentrations of the estrogenic components of STW effluents. In this paper, it was established that the concentrations of natural steroid estrogens and xenoestrogens (alkylphenolic chemicals) in a treated sewage effluent fluctuated temporally (over 8 months), from between 36 and 308 ng/L and between <0.2 (detection limit) and 10.7 μg/L, respectively. Long-term exposure of maturing adult roach to a graded concentration of this effluent (0, 9.4,...

Field Measurement and Modelling the Fate of Aniline and Lindane in a UK Lowland River

The application of models to predict the behaviour of chemicals in the aquatic environment will assume increasing importance as the sophistication of river pollution management increases. A field validation of a model which enables such predictions, the US EPA EXAMS II model, is reported. The study was carried out on a stretch of a UK lowland river, the River Calder in West Yorkshire, and utilised a sewage treatment works (STW) effluent discharge as a point source of the two chemicals, aniline and lindane, modelled. Concentrations of aniline and lindane were measured in samples of water, suspended particulates and sediments taken from the river and STW effluent and the measured results compared with those predicted by the EXAMS model. Good agreements were generally obtained between the model predictions and the measured values for the water and bed sediment, but the levels measured in the suspended particulates were significantly higher than those predicted. The most likely explanation for this discrepancy was that the equilibrium partitioning approach employed by EXAMS was inappropriate for the suspended particulate associated chemicals. However, since the majority (>>95%) of both aniline and lindane in the water column was in the dissolved phase, this was not a significant drawback to the use of EXAMS for the prediction of fate and behaviour.