Assessment of Sewage Molecular Markers: Linear Alkylbenzenes in Sediments of an Industrialized Region in Peninsular Malaysia (original) (raw)
Related papers
Water Research, 2004
This paper reports the result of sewage pollution monitoring conducted in South and Southeast Asia during 1998-2003 using linear alkylbenzenes (LABs) as molecular tracers of sewage contamination. Eighty-nine water samples collected from Malaysia, Vietnam, and Japan (Tokyo), and 161 surface sediment samples collected from Tokyo, Thailand, Malaysia, Philippines, Vietnam, Cambodia, Indonesia, and India were analyzed for alkylbenzenes. The concentration range of P LABs in river water particles in Southeast Asia (o0.005-0.913 mg/L) was comparable to or higher than those found in Tokyo (o0.005-0.638 mg/L). I/E ratios (a ratio of internal to external isomers of LABs) in tropical Asian waters were close to the value of LABs in raw sewage (B1) and much lower than those in secondary effluents . This suggests that untreated or inadequately treated sewage is discharged into the water. P LABs concentrations in sediments from South and Southeast Asia ranged from o0.002-42.6 mg/g-dry with the highest concentration occurring at several populous cities. Low I/E ratios of the sediments with high P LABs concentrations suggest a heavy load of untreated sewage. Clearly in view of the current data and evidence of the implications of sewage pollution, this paper highlights the necessity of the continuation of water treatment system improvement in tropical Asia. r
Distribution of Linear Alkylbenzenes (LABs) in Sediments of Sarawak and Sembulan Rivers, Malaysia
2012
The current study is one of the first studies evaluating the levels of linear alkylbenzenes (LABs) in surface sediments of Sarawak and Sembulan rivers which are located in the east coast of Malaysia. The LABs, which are molecular tracers of sewage contamination, were measured in 15 surface sediment samples collected from these rivers. The samples were extracted, fractioned and analyzed by gas chromatography mass spectrometry (GC-MS). The findings revealed that the concentrations of ΣLABs ranged from 156.47 to 7386.19 ng/g dry weight (dw) in the sediments of Sarawak River and from 643.18 to 5567.12 ng/g dw in the sediments of Sembulan River. The highest LABs levels were detected in the sediments collected from the sampling location SS9 in Sembulan River whereas the lowest levels were observed in the SS1 sampling location in Sarawak River. The I/E ratios (ratio of internal to external isomers of LABs) for Sarawak River sediments ranged from 0.52 to 0.98 while for Sembulan River they fell within the range 0.87-1.79. The I/E ratio at the sampling station SS4 was much lower than the I/E ratios at the other stations, thus indicating that the wastewater discharged into Sarawak River from the areas surrounding station SS4 was poorly treated.
2009
The current study is one of the first studies evaluating the levels of linear alkylbenzenes (LABs) in surface sediments of Sarawak and Sembulan rivers which are located in the east coast of Malaysia. The LABs, which are molecular tracers of sewage contamination, were measured in 15 surface sediment samples collected from these rivers. The samples were extracted, fractioned and analyzed by gas chromatography mass spectrometry (GC-MS). The findings revealed that the concentrations of ΣLABs ranged from 156.47 to 7386.19 ng/g dry weight (dw) in the sediments of Sarawak River and from 643.18 to 5567.12 ng/g dw in the sediments of Sembulan River. The highest LABs levels were detected in the sediments collected from the sampling location SS9 in Sembulan River whereas the lowest levels were observed in the SS1 sampling location in Sarawak River. The I/E ratios (ratio of internal to external isomers of LABs) for Sarawak River sediments ranged from 0.52 to 0.98 while for Sembulan River they fell within the range 0.87-1.79. The I/E ratio at the sampling station SS4 was much lower than the I/E ratios at the other stations, thus indicating that the wastewater discharged into Sarawak River from the areas surrounding station SS4 was poorly treated.
Environmental Pollution, 2014
Babitonga Bay is a South Atlantic estuary with significant ecological function; it is part of the last remaining areas of mangrove communities in the Southern Hemisphere. The aim of this study was to determine the spatial distribution of the faecal sterols and linear alkylbenzenes (LABs) in surface sediments and to perform an integrated evaluation of several molecular marker indices to assess the sewage contamination status in the study area. The highest observed concentrations of faecal sterols (coprostanol þ epicoprostanol) and LABs were 6.65 mg g À1 and 413.3 ng g À1 , respectively. Several faecal sterol indices were calculated and correlated with coprostanol levels; these analyses showed that the index limits presented in the current literature could underestimate the sewage contamination in this study area. For the overall estuarine system, a low sewage impact may be assumed based on the low total mass inventories calculated for coprostanol (between 1.4% and 4.8%).
Journal of Water and Wastewater, 2020
Linear alkylbenzenes is one of the most important surfactants in the industry. Due to their source specificity, degradation resistance and long-term survival in marine sediments, these compounds are unique molecular markers for studying organic matter input derivatives and their effects on aquatic environments. Due to the presence of multiple sources of these compounds in the study areas, this study was conducted to determine the linear alkyl benzene concentrations in the 5 rivers of Nekaroud, Tajan, Talaroud, Babolroud and Sorkhroud that lead to the Caspian Sea. In this study, 15 river samples were collected from the bottom of rivers (near estuaries) from 0-5 cm depth by Grab van veen device. After preparation, the extracted samples were injected into a gas chromatography-mass spectrometer (GC-MS). Finally, the concentration of linear alkyl benzene compounds in surface sediments of 5 rivers leading to the Caspian Sea was determined. The average concentration of linear alkylbenzene compounds in rivers was determined in the range of 56730/28-91288/58 ng/g dry weight. Based on the results, stations in the densely populated and urban areas showed higher concentrations of these compounds. There was also a positive correlation between these compounds and total organic carbon (TOC) (p< 0.05). Therefore, the concentration changes of these compounds are a function of the TOC concentration changes in the sediments. The ratio of internal to external isomers (I/E) in the studied rivers ranged from 0.25 to 0.44. High concentrations of alkyl benzene with a low I/E ratio showed that the streams of Mazandaran province were heavily influenced by human activities. According to cluster analysis, Nekaroud and Tajan rivers have lower concentration than other rivers and are more desirable for release of fish than other rivers.
Environmental Toxicology and Chemistry, 1997
Linear alkylbenzenes (LABs) were detected in the Point Loma Wastewater Treatment Plant (PLWTP) effluent, Tijuana River runoff, microlayer, water column particulates, and sediments collected off the coast of San Diego in 1994. The distributions of LABs in various media and sampling locations suggested that these compounds were essentially derived from domestic waste discharges. The PLWTP outfall is a major source for LAB inputs, while the Tijuana River runoff discharges much lower amounts of LABs. However, the contents of sewage-derived organics can be enhanced in the sea surface microlayer near the mouth of the Tijuana River. In addition, the I/E ratios indicated that 30-55% of the LABs were degraded in the water column particulates and sediments. Other processes (e.g., dilution, evaporation, bioaccumulation, etc.) may also be important in removing LABs from the discharge zone. Sewage-derived organic materials can be carried into remote areas via suspension of fine particulates. Keywords-Linear alkylbenzenes Sewage tracer Transport and fate Coastal marine environment 12 12 I/E ϭ ⌺ (C-LAB-4 ϩ C-LAB-3 ϩ C-LAB-2) 12 12 12 A high I/E value indicates a high degree of LAB biodegradation, due to the selective biodegradation of the external isomers relative to the internal isomers [19]. Using linear alkylbenzenes to trace sewage-derived materials
Environmental pollution (Barking, Essex : 1987), 2018
The molecular markers sterols and linear alkylbenzenes (LABs) were analyzed in the surficial sediments and suspended particulate matter (SPM) of a subtropical estuary in South Atlantic (Paranaguá Estuarine System). The purpose of this study was identify the spatial distribution of sewage and the input of biogenic organic matter (OM) and to provide comparative insights about their behavior, compositions, and sources. The concentration of coprostanol ranged from < DL (detection limit) to 2.67 μg g in SPM and from < DL to 0.94 μg g in sediments. Total LABs ranged from 43.8 to 480.0 ng g in SPM and from < DL to 21.0 ng g in sediments. LABs homologs composition varied between the two matrices. The local hydrodynamic pattern may promote water column homogenization, dispersion, and dilution of sewage particles, and preferential sedimentation in fluvial and mixture zones. Results suggest that SPM is a good matrix for larger spatial and short time scale evaluation while sediments ma...
2009
Environmental pollution has become a major concern in all aspect of the world. This pollution appears to be everywhere including the coastal areas. Coastal zones, especially bays, estuaries, shoals, and reefs near large cities or the mouths of major rivers, often overwhelmed by human-caused contamination. High levels of toxic chemicals, heavy metals, disease-causing organisms, oil, sediment, and plastic refuse are adversely affecting some of the most attractive and productive ocean regions. The potential losses caused by this pollution amount to billions of dollars each year. Rivers and estuaries in Malaysia are important for fisheries, recreational and marine activities, tourism, and maintaining biodiversity in the tropical area. However, the rivers and estuaries are under constant threat of various pollutions. One of the major threats is organic pollutants. There are varieties of potential sources such as industrial and commercial development, shipping industries and other human activities.
Distribution of PAHs and N-Alkanes In Klang River Surface Sediments, Malaysia
bakkdev.um.edu.my, 2002
Surface sediment samples were collected from five locations at the downstream of Klang River in January 2007 to examine the spatial distribution, composition, and sources of 19 parent polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbon (n-alkanes) using gas chromatographymass spectrometry. The total concentrations of the 19 PAHs in the sediments were found to range from 1304 to 2187 ng g-1 sediment. Meanwhile, total concentrations of n-alkanes ranged from 17008 to 27116 µg g-1 sediment. The concentration of n-alkanes in the sediment was significantly correlated (r = 0.991, p = 0.001) with the content of sediment organic carbon. In this study, all the sediments exhibited phenanthrene/anthracene (PHE/ANT >15) fluoranthene/(fluorantene+pyrene) (FLT/FLT+PYR < 0.4), methylphenanthrenes/phenanthrene (MP/P >1), combustion PAHs/total PAHs (CombPAH/∑19PAH <0.3), terrigenous/aquatic ratio for hydrocarbons greater than 23. The also data showed that petrogenic and natural inputs were predominant at all the locations investigated. Multiple sources of n-alkanes and PAHs in the river sediments were also explained by low carbon preference index (CPI) values, different ratios of diploptene/∑C 23-C 25 n-alkanes, poor correlation between diploptene and ∑C 23-C 25 , average chain length (ACL) of 29.54 ± 0.09, correlation between CPI and ACL (r = 0.847, p= 0.035), and high ratio of naphthalene/total PAHs.