Occurrence, fate, and fluxes of perfluorochemicals (PFCs) in an urban catchment: Marina Reservoir, Singapore

2012 ◽  
Vol 66 (11) ◽  
pp. 2439-2446 ◽  
Author(s):  
Viet Tung Nguyen ◽  
Karina Yew-Hoong Gin ◽  
Martin Reinhard ◽  
Changhui Liu
Keyword(s):  
Sea Water ◽  
Transformation Products ◽  
Point Sources ◽  
Storm Runoff ◽  
Storm Events ◽  
Urban Catchment ◽  
Sources And Sinks ◽  
Approximation Analysis ◽  
High Concentrations ◽  
Dry Weather Flow

A study was carried out to characterize the occurrence, sources and sinks of perfluorochemicals (PFCs) in the Marina Catchment and Reservoir, Singapore. Salinity depth profiles indicated the reservoir was stratified with lower layers consisting of sea water (salinity ranging from 32 to 35 g L−1) and a brackish surface layer containing approximately 14–65% seawater. The PFC mixture detected in catchment waters contained perfluoroalkyl carboxylates (PFCAs), particularly perfluorooctanoate (PFOA), perfluorohexanoate (PFHpA), perfluorooctane sulfonate (PFOS) and PFC transformation products. PFC concentrations in storm runoff were generally higher than those in dry weather flow of canals and rivers. PFC concentration profiles measured during storm events indicated ‘first flush’ behavior, probably because storm water is leaching PFC compounds from non-point sources present in the catchment area. Storm runoff carries high concentrations of suspended solids (SS), which suggests that PFC transport is via SS. In Marina Bay, PFCs are deposited in the sediments along with the SS. In sediments, the total PFC concentration was 4,700 ng kg−1, approximately 200 times higher than in the bottom water layers. Total perfluoroalkyl sulfonates (PFSAs), particularly PFOS and 6:2 fluoro telomer sulfonate (6:2 FtS) were dominant PFCs in the sediments. PFC sorption by sediments varied with perfluorocarbon chain length, type of functional group and sediment characteristics. A first approximation analysis based on SS transport suggested that the annual PFC input into the reservoir was approximately 35 ± 12 kg y−1. Contributions of SS, dry weather flow of river/canals, and rainfall were approximately 70, 25 and 5%, respectively. This information will be useful for improving strategies to protect the reservoir from PFC contamination.

COASTAL AND ESTUARINE SEDIMENT DYNAMICS IN THE MEZEN BAY AND ESTUARIES MEZEN AND KULOY

2018 ◽  
Author(s):  
Н. Демиденко ◽  
N. Demidenko
Keyword(s):  
River Water ◽  
River Discharge ◽  
Sea Water ◽  
Sediment Dynamics ◽  
Estuarine Sediment ◽  
Sea Surface ◽  
Cross Sectional ◽  
Sand Waves ◽  
Tidal Estuaries ◽  
High Concentrations

In the Mezen bay and estuaries Mezen and Kuloy can be high concentrations of mud suspension there, involving the formation at times mobile suspensions and settled mud. Within estuaries the river water is mixed with the sea water by the action of tidal motions, by waves on the sea surface and by the river discharge forcing its way to the sea. Nearly all shallow tidal estuaries, where currents exceed about 1,0m s-1 and where sand is present, have sand waves. Sand waves have a variety of cross-sectional and plan forms.

First flush effects in an urban catchment area in Aalborg

1998 ◽  
Vol 37 (1) ◽  
pp. 251-257 ◽  
Author(s):  
Torben Larsen ◽  
Kirsten Broch ◽  
Margit Riis Andersen
Keyword(s):  
Water Quality ◽  
Catchment Area ◽  
Quality Parameters ◽  
Average Concentration ◽  
First Flush ◽  
Storm Events ◽  
Urban Catchment ◽  
Discharge Measurements ◽  
Quality Measurements

The paper describes the results of measurements from a 2 year period on a 95 hectare urban catchment in Aalborg, Denmark. The results of the rain/discharge measurements include 160 storm events corresponding to an accumulated rain depth of totally 753 mm. The water quality measurements include 15 events with time series of concentration of SS, COD, BOD, total nitrogen and total phosphorus. The quality parameters showed significant first flush effects. The paper discusses whether either the event average concentration or the accumulated event mass is the most appropriate way to characterize the quality of the outflow.

Bank filtration: a suitable process for the removal of iodinated X-ray contrast media?

2004 ◽  
Vol 50 (5) ◽  
pp. 261-268 ◽  
Author(s):  
S. Schittko ◽  
A. Putschew ◽  
M. Jekel
Keyword(s):  
Drinking Water ◽  
Contrast Media ◽  
Surface Waters ◽  
Sampling Period ◽  
Transformation Products ◽  
Bank Filtration ◽  
Anoxic Conditions ◽  
X Ray ◽  
High Concentrations ◽  
Media Concentration

After bank filtration, effluent influenced surface waters are often used as raw drinking water. It is known that high concentrations of iodinated X-ray contrast media are detectable in such surface waters and thus, more knowledge about the behaviour of the contrast media during bank filtration is necessary and the subject of investigations in this study. The adsorbable organic iodine (AOI), four widely used iodinated X-ray contrast media and four possible transformation products were quantified in an influenced lake, five groundwater wells and a drinking water well. Under anoxic conditions the AOI as well as the concentration of the contrast media are decreased by bank filtration, whereby the AOI is decreased by 64% and the contrast media concentration can be reduced up to 95%, depending on the compound. In the raw drinking water the following average concentrations were determined: Iopromid <20 ng/L, Diatrizote 166 ng/L, Iopamidol 166 ng/L and Iohexol 34 ng/L. Instationary conditions during the sampling period indicate that, at least under anoxic conditions, a large part of the contrast media and transformation products, which are still iodinated, may be associated to colloids and/or humic material.

scholarly journals Assessing dry weather flow contribution in TSS and COD storm events loads in combined sewer systems

2011 ◽  
Vol 63 (12) ◽  
pp. 2983-2991 ◽  
Author(s):  
M. Métadier ◽  
J. L. Bertrand-Krajewski
Keyword(s):  
Time Series ◽  
Oxygen Demand ◽  
Seasonal Effect ◽  
Storm Events ◽  
Combined System ◽  
Time Step ◽  
Urban Catchment ◽  
Sewer Systems ◽  
Continuous Discharge

Continuous high resolution long term turbidity measurements along with continuous discharge measurements are now recognised as an appropriate technique for the estimation of in sewer total suspended solids (TSS) and Chemical Oxygen Demand (COD) loads during storm events. In the combined system of the Ecully urban catchment (Lyon, France), this technique is implemented since 2003, with more than 200 storm events monitored. This paper presents a method for the estimation of the dry weather (DW) contribution to measured total TSS and COD event loads with special attention devoted to uncertainties assessment. The method accounts for the dynamics of both discharge and turbidity time series at two minutes time step. The study is based on 180 DW days monitored in 2007–2008. Three distinct classes of DW days were evidenced. Variability analysis and quantification showed that no seasonal effect and no trend over the year were detectable. The law of propagation of uncertainties is applicable for uncertainties estimation. The method has then been applied to all measured storm events. This study confirms the interest of long term continuous discharge and turbidity time series in sewer systems, especially in the perspective of wet weather quality modelling.

scholarly journals Exposure of the Main Italian River Basin to Pharmaceuticals

2011 ◽  
Vol 2011 ◽  
pp. 1-11 ◽  
Author(s):  
Federico Ferrari ◽  
Agata Gallipoli ◽  
Matteo Balderacchi ◽  
Maria M. Ulaszewska ◽  
Ettore Capri ◽  
...  
Keyword(s):  
Surface Waters ◽  
Point Sources ◽  
Preliminary Survey ◽  
Italian Economy ◽  
Sediment Samples ◽  
Pharmaceutical Contamination ◽  
Low Levels ◽  
High Concentrations ◽  
River Po ◽  
Sources Of Contamination

This study give a preliminary survey of pharmaceutical contamination and accumulation in surface waters and sediments along the river Po basin (74,000 km2, the largest in Italy), a strategic region for the Italian economy: it collects sewage from a vast industrialized area of Italy (Autorità di Baciono del fiume Po, 2006, 2009). 10 pharmaceuticals (atenolol, propanolol, metoprolol, nimesulide, furosemide, carbamazepine, ranitidine, metronidazole, paracetamol, and atorvastatin) from several therapeutic classes were searched in 54 sampling points along the river Po from the source to the delta, and at the mouth of its major effluents. In water samples were found pharmaceuticals in the range of 0.38–0.001 μg/L, except for furosemide (max conc. 0.605 μg/L), paracetamol (max conc. 3.59 μg/L), metoprolol (never detected) and for atenolol (not analysed). In sediment samples, only paracetamol was not detected, while the others were generally found in the range of 0.4–0.02 μg/kgwwwith high concentrations for atenolol (max conc. 284μg/kgww) and furosemide (max conc. 98.4μg/kgww). The findings confirm also STPs as point sources of contamination. Despite of the much evidence for the adverse effects of pharmaceuticals in the aquatic environment, the observed low levels cannot be considered to pose a serious risk to human health; further studies are necessary for a comprehensive risk assessment.

A Micropuncture Study of Kidney Function in the River Lamprey Lampetra Fluviatilis Adapted to Sea Water

1980 ◽  
Vol 88 (1) ◽  
pp. 239-248
Author(s):  
A. G. LOGAN ◽  
R. MORRIS ◽  
J. C. RANKIN
Keyword(s):  
Fresh Water ◽  
Kidney Function ◽  
Sea Water ◽  
Chloride Ions ◽  
Water Reabsorption ◽  
Plasma Electrolyte ◽  
River Lamprey ◽  
Micropuncture Study ◽  
Urine Composition ◽  
High Concentrations

Micropuncture techniques have been used to investigate kidney function in lampreys adapted to hyperosmotic media. Plasma electrolyte concentrations were maintained well below corresponding concentrations in the external environment. Urine composition was variable, but generally showed high concentrations of magnesium, sulphate and chloride ions. Lampreys in 50% sea water produced urine which was hypo or iso-osmotic to plasma, whereas those in 100% sea water produced hyperosmotic urine. Urine flow rate in 50% sea water was one tenth of that in fresh water, due to a reduction in filtration rate and an increase in water reabsorption by the kidney. As in fresh water, little if any filtered water was reabsorbed by the proximal segment. Almost 90% of filtered water was reabsorbed by the kidney of 100% sea water lampreys and most of this must have occurred in the distal and collecting segments.

Runoff quality and pollution loadings from a tropical urban catchment

2005 ◽  
Vol 52 (9) ◽  
pp. 125-132 ◽  
Author(s):  
Z. Yusop ◽  
L.W. Tan ◽  
Z. Ujang ◽  
M. Mohamed ◽  
K.A. Nasir
Keyword(s):  
Water Quality ◽  
Open Space ◽  
Quality Standards ◽  
Storm Events ◽  
Water Quality Standards ◽  
Class V ◽  
Urban Catchment ◽  
River Quality ◽  
Runoff Quality ◽  
National Water

Runoff quality draining from 17.14km2 urban catchment in Johor Bahru, Malaysia, was analysed. The land-use consists of residential (30.3%), agricultural (27.3%), open space (27.9%), industrial (8.1%) and commercial (6.4%) areas. Three storm events were sampled in detail. These storms produced stormflow between 0.84mm and 27.82mm, and peakflow from 2.19m3/s to 42.36m3/s. Water quality showed marked variation during storms especially for TSS, BOD and COD with maximum concentrations of 778mg/l, 135mg/l and 358mg/l, respectively. Concentrations of TOC, DOC, NH3-N, Fe and level of colour were also high. In general, the river quality is badly polluted and falls in Class V based on the Malaysian Interim National Water Quality Standards. Event Mean Concentrations (EMC) for various parameters varied considerably between storms. The largest storm produced higher EMC for TSS, NO3-N and SS whereas the smaller storms tend to register higher EMC for BOD, COD, NH3-N, TOC, Ca, K, Mg, Fe and Zn. Such variations could be explained in terms of pollutant availability and the effects of flushing and dilution. Based on a three-month average recurrence interval (ARI) of rainfall, the estimated event loadings (ton/ha) of TSS, BOD, COD, TOC, NH3-N and NO3-N were 0.055, 0.016, 0.012, 0.039, 0.010, 0.0007 and 0.0002, respectively. Heavy metals present in trace quantities. Storms with 3 months ARI could capture about 70% of the total annual loads of major pollutants.

scholarly journals Concentrations and Loads of Dissolved and Particulate Organic Carbon in Urban Stormwater Runoff

Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1031 ◽  
Author(s):  
Stefan Kalev ◽  
Gurpal S. Toor
Keyword(s):  
Organic Carbon ◽  
Stormwater Runoff ◽  
Light Availability ◽  
Rain Gauge ◽  
Urban Landscapes ◽  
Storm Events ◽  
Wet Season ◽  
The Difference ◽  
Urban Stormwater Runoff ◽  
High Concentrations

Urban landscapes are significant contributors of organic carbon (OC) in receiving waters, where elevated levels of OC limit the light availability, increase the transport of pollutants, and result in high costs of potable water treatment. Our objective in this study was to investigate the concentrations, fractions (dissolved and particulate), and loads of OC in a residential catchment (3.89 ha drainage area) located in Florida, United States. The outlet of the stormwater pipe draining the residential catchment was instrumented with an automated sampler, a flowmeter, and a rain gauge. The rainfall and runoff samples collected over 25 storm events during the 2016 wet season (June to September) were analyzed for dissolved organic carbon (DOC) and total organic carbon (TOC), with particulate OC (POC) calculated as the difference between TOC and DOC. Mean concentration of DOC was 2.3 ± 1.7 mg L−1 and POC was 0.3 ± 0.3 mg L−1 in the rainfall, whereas DOC was 10.5 ± 6.20 mg L−1 and POC was 2.00 ± 4.05 mg L−1 in the stormwater runoff. Concentrations of DOC were higher during the rising limb of the hydrograph in 15 out of 25 storm events, suggesting flushing of DOC, with an increase in the amount of runoff, from the landscape sources in the residential catchment. The estimated total export of OC during the 2016 wet season was 66.0 kg ha−1, of which DOC was 56.9 kg ha−1 (86.2% of TOC), and POC was 9.1 kg ha−1 (13.8% of TOC). High concentrations and loads of OC, especially DOC, in the stormwater runoff imply that residential catchments in urban watersheds are hot-spots of DOC influx to water bodies. Reducing DOC transport in the urban landscapes is complex and require identifying the origin of DOC and then using site-specific targeted approaches to mitigate DOC loss.

The Effect of Salt Stress on the Catabolism of Sugars in Leaves and Roots of a Mangrove Plant, Avicennia marina

1997 ◽  
Vol 52 (3-4) ◽  
pp. 187-192 ◽  
Author(s):  
Yuko Fukushima ◽  
Hamako Sasamoto ◽  
Shigeyuki Baba ◽  
Hiroshi Ashihara
Keyword(s):  
Malic Acid ◽  
Sea Water ◽  
Tca Cycle ◽  
Avicennia Marina ◽  
Salt Resistance ◽  
Pentose Phosphate ◽  
Neutral Fraction ◽  
Mangrove Plant ◽  
High Concentrations ◽  
Old Trees

Abstract Respiration and related aspects of metabolism were investigated in the roots and leaves of 2-year-old trees of the mangrove plant, Avicennia marina in the presence of 100, 250 and 500 mᴍ NaCl. The rate of respiration of leaves increased with increasing concentrations of NaCl in the incubation medium, but respiration of roots was not similarly affected. In order to examine the relative rates of catabolism of glucose by the glycolysis-tricarboxylic acid (TCA) cycle and the oxidative pentose phosphate pathway (PP pathway), we determined the rates of release of 14CO2 from [1-14C]glucose and from [ 6 -14C]glucose in segments of roots and leaves. The ratios of rates (C6/C1) in roots varied from 0.30 to 0.44, while ratios of 0.85 to 0.99 were obtained when leaves were incubated in the presence of various concentrations of NaCl. It appeared that the PP pathway was more involved in sugar catabolism in the roots than in the leaves of A. marina. Uniformaly 14C-labelled sucrose, incubated with segments of roots and leaves for 18 h, was converted to CO2, amino acids (mainly glutamine), organic acids (mainly malic acid), sugars and ethanol-insoluble macromolecules. The incorporation of radioactivity into most of these components was not significantly affected by NaCl. However, in leaves (but not in roots) the release of 14CO2 from [ U -14C]sucrose was en­ hanced by NaCl at 250 mᴍ and 500 mᴍ, while the rate of incorporation of radioactivity into macromolecules was reduced by high concentrations of NaCl. Incorporation of radioactivity from [ U -14C]sucrose into malic acid was enhanced in both roots and leaves by an increase in the concentration of NaCl from 100 mᴍ to 500 mᴍ (this concentrations is similar to that in sea water). Independent of the concentration of NaCl, more than half of the radioactivity in the neutral fraction from leaves was incorporated into an unidentified sugar, while in the same fraction from roots, the radioactivity was associated with glucose, fructose and sucrose. On the basis of these results, a discussion is presented of the characteristics of catabolism of sugars in A. marina in relation to salt resistance.

scholarly journals First flush of storm runoff pollution from an urban catchment in China

2007 ◽  
Vol 19 (3) ◽  
pp. 295-299 ◽  
Author(s):  
Li-qing LI ◽  
Cheng-qing YIN ◽  
Qing-ci HE ◽  
Ling-li KONG
Keyword(s):  
Storm Runoff ◽  
First Flush ◽  
Urban Catchment ◽  
Runoff Pollution
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