Occurrence and distribution of linear alkylbenzene sulfonates and sulfophenylcarboxylic acids in several Iberian littoral ecosystems

The distribution of linear alkylbenzene sulfonates (LAS) and sulfophenylcarboxylic acids (SPC) has been characterized in water and sediment of five Iberian estuaries and a saltmarsh channel. The highest concentrations of LAS and SPC were detected in shallow zones close to discharge points of untreated urban effluent, and decreased sharply with increasing distance from these. SPC homologues of between 3 and 12 carbon atoms were detected, although their concentrations were several orders of magnitude lower than the corresponding LAS. The highest SPC concentrations found were of medium carboxylic chain lengths (C6-C8) in water, and of longer chain lengths (C9-C11) in particulate material. LAS homologues were associated preferentially with the particulate material. The vertical distribution of LAS in the water column was not homogeneous, in contrast to that presented by the SPC homologues. In the case of the Sancti Petri Channel, there was a net flow of LAS exportation into the Bay of Cádiz, of -38.6 kg day(-1), and a net flow for SPC of -6.0 kg day(-1). The daily mass input of LAS and their biodegradation intermediates from the Sancti Petri Channel to Cadiz Bay was 44.6 kg.     

Distribution of linear alkylbenzenes (LABs) in riverine and coastal environments in South and Southeast Asia

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 SigmaLABs in river water particles in Southeast Asia (<0.005-0.913 microg/L) was comparable to or higher than those found in Tokyo (<0.005-0.638 microg/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 ( approximately 1) and much lower than those in secondary effluents (3-5). This suggests that untreated or inadequately treated sewage is discharged into the water. SigmaLABs concentrations in sediments from South and Southeast Asia ranged from <0.002-42.6 microg/g-dry with the highest concentration occurring at several populous cities. Low I/E ratios of the sediments with high SigmaLABs 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.     

Microanalysis of anionic surfactants in waste water by infrared spectroscopy

Infrared spectroscopy was applied to identify and determine microamounts of anionic surfactants contained in sewage or river waters. The surfactants tested were linear alkylbenzene sulfonate (LAS), branched alkylbenzene sulfonate (ABS), alpha olefine sulfonate (AOS), fatty alcohol sulfate (AS) and fatty alcohol ethoxy sulfate (AES).Anionic surfactants in waters were extracted by chloroform as methylene blue complexes and sulfate type surfactants, i.e. AS and AES were then removed by subsequent hydrolysis. Residual sulfonate type surfactants were first released from methylene blue complexes by ion exchange technique and then changed to sulfonyl chloride derivatives for infrared spectroscopy. Key bands for the identification of sulfonate type surfactants are 640, 618 and 524 cm⁻¹ for LAS, ABS and AOS, respectively. Sulfate type surfactants was calculated from the difference of methylene blue active substance contents before and after hydrolysis.     

Determination of trace levels of linear alkylbenzenesulfonates in the marine environment by high-performance liquid chromatography

The widespread and increasing use of linear alkylbenzenesulfonates (LAS) has shown the need for analytical procedure of LAS. A method has been developed to isolate, concentrate and determine trace levels of LAS from marine environmental samples. LAS were extracted with Bond Elut C₁₈ reversed-phase minicolumn and quantified by high-performance liquid chromatography with fluorophotometric detection. This method can determine trace levels of LAS, simply, rapidly, specifically and sensitively and minimize the risk of contamination. This method showed the limit of determination for each LAS component of approx. 0.1 μg l⁻¹ for water, 0.03 μg g⁻¹ (dry basis) for bottom sediment or 0.3 μg g⁻¹ (wet basis) for fish sample, the recovery of 80% for water, 87% for sediment or 86% for fish sample, and the reproduceability of 3–4% relative standard deviation for five-replicated analysis of sea water or sea sediment.This proposed method was employed for the determination of LAS in marine environmental samples of Tokyo bay, Japan. A concentration range between 0.8 and 30 μg l⁻¹ of LAS was found in Tokyo bay water. The highest concentration was detected in the coastal areas.     

Occurrence of selected surfactants in untreated and treated sewage

Several surfactants were monitored in treated and untreated sewage in nine municipal wastewater treatment plants (WWTPs) in western Austria. The nine sampled WWTPs cover a wide variety referring to size and applied treatment technology. The investigation focused on linear alkylbenzene sulphonate (LAS), quaternary ammonia compounds (QAC), nonylphenol (NP), octylphenol (OP), nonylphenolmono- (NP(1)EO) and -diethoxylates (NP(2)EO). Whereas LAS, NP, OP and NP(1,2)EO were analysed separately in the liquid phase and in the solid phase, the QACs were measured in the total sample. Total influent concentrations of LAS varied between 2.4 mg l(-1) up to 6.7 mg l(-1) whereas total effluent concentrations were in the lower microg l(-1) range (11-50 microg l(-1)). Whichever the type of treatment, a clear removal during treatment was observed. Solid liquid distribution coefficients K(d) were calculated for untreated sewage. The calculated K(d) values varied between 1300 and 3900 l kg(-1). OP was of minor importance with total influent concentrations below 1microg l(-1). NP and NP(1,2)EO were present in all analysed influents in concentrations between 1 and 35microg l(-1). Effluent concentrations were notably lower than the measured influent concentrations. K(d) values for NP varied between 500 and 6600 l kg(-1), for NP(1)EO between 800 and 2700 l kg(-1) and for NP(2)EO between 100 and 1800 l kg(-1). From the QACs several alkyl benzyl (BAC), dialkyl (DDAC) and trialkyl (ATAC) ammonium chlorides with varying alkyl chain lengths were analysed. Highest total concentrations in the influents to the WWTPs were observed for the BAC-C12 and the ATAC-C16 homologues. Effluent concentrations were notably lower compared to influent concentrations, indicating removal by adsorption and/or biodegradation. The influence of the removal by adsorption increased with increasing alkyl chain length.     

Arsenic in hair and nails of individuals exposed to arsenic-rich groundwaters in Kandal province, Cambodia

The health implications of the consumption of high arsenic groundwater in Bangladesh and West Bengal are well-documented, however, little is known about the level of arsenic exposure elsewhere in Southeast Asia, where widespread exploitation of groundwater resources is less well established. We measured the arsenic concentrations of nail and hair samples collected from residents of Kandal province, Cambodia, an area recently identified to host arsenic-rich groundwaters, in order to evaluate the extent of arsenic exposure. Nail and hair arsenic concentrations ranged from 0.20 to 6.50 microg g(-1) (n=70) and 0.10 to 7.95 microg g(-1) (n=40), respectively, in many cases exceeding typical baseline levels. The arsenic content of the groundwater used for drinking water purposes (0.21-943 microg L(-1) (n=31)) was positively correlated with both nail (r=0.74, p<0.0001) and hair (r=0.86, p<0.0001) arsenic concentrations. In addition, the nail and hair samples collected from inhabitants using groundwater that exceeded the Cambodian drinking water legal limit of 50 microg L(-1) arsenic contained significantly more arsenic than those of individuals using groundwater containing <50 microg L(-1) arsenic. X-ray absorption near edge structure (XANES) spectroscopy suggested that sulfur-coordinated arsenic was the dominant species in the bulk of the samples analysed, with additional varying degrees of As(III)-O character. Tentative linear least squares fitting of the XANES data pointed towards differences in the pattern of arsenic speciation between the nail and hair samples analysed, however, mismatches in sample and standard absorption peak intensity prevented us from unambiguously determining the arsenic species distribution. The good correlation with the groundwater arsenic concentration, allied with the relative ease of sampling such tissues, indicate that the arsenic content of hair and nail samples may be used as an effective biomarker of arsenic intake in this relatively recently exposed population.     

Urban population exposure to lead and cadmium in east and south-east Asia

Information is still scarce for many Asian countries on general population exposure to two potentially toxic heavy metals of lead (Pb) and cadmium (Cd). The present review on publications from this study group is intended to provide an overview of the non-occupational exposure to Pb and Cd among general populations in east and south-east Asia. During the period of 1991-1998, surveys were conducted in four cities in south-east Asia, five cities in mainland China, and two cities each in Japan and Korea. Peripheral blood, morning spot urine and 24-h food duplicate samples were collected from 20-50 non-smoking adult women in each survey site. The samples were digested by heating in the presence of mineral acids, and then analyzed by inductively-coupled plasma mass spectrometry for the metals in blood (Pb-B and Cd-B), in urine (Pb-U and Cd-U), and in food duplicate (Pb-F and Cd-F). Measures were subjected to statistical analysis with an assumption of log-normal distribution. Pb-B, Pb-U and Pb-F levels varied substantially among the 11 urban sites; GM distributed in ranges of 32-65 microg/l for Pb-B, 2.1-7.5 microg/g cr (creatinine) for Pb-U, and 7-32 microg/day for Pb-F. The same was also the case for Cd exposure parameters, the distribution ranges being 0.5-1.8 microg/l for Cd-B, 1.2-3.1 microg/g cr for Cd-U, and 5-32 microg/day for Cd-F. It appeared that the exposure to Pb and Cd was highest in Kuala Lumpur, and Tokyo + Kyoto, respectively, and lowest in Tokyo + Kyoto and in Manila. Additional surveys in Japan showed that Pb exposure was even lower in rural areas than in Tokyo + Kyoto. When compared with the values reported in the literature, Pb exposure levels among Asian populations appear to be similar to the levels in Europe and in the United States, whereas Cd exposure seems to be higher in Asia than in Europe. The contribution of the dietary route in Pb absorption was variable and was inversely related to the extent of air pollution, whereas Cd uptake was almost exclusively via the dietary route with little contribution of the respiratory route.     

Influence of the hydrophilic moiety of anionic and nonionic surfactants on their aerobic biodegradation in seawater

The extent and kinetics of the primary biodegradation have been characterized for the most commonly-used surfactants, employing four homologues with the same alkyl chain: dodecyl ethoxy sulfate (C₁₂AES), sodium dodecyl sulfate (SDS), dodecyl alcohol ethoxylate (C₁₂AEO) and dodecyl benzenesulfonate (C₁₂LAS). A brief acclimatization period has been required to enable an effective degradation of C₁₂LAS and C₁₂AES to take place, but this lag phase has not been detected for SDS and C₁₂AEO. Primary biodegradation percentages at the end of these experiments were higher than 99%, showing a fast degradation rate in all cases (average half-life lower than 2 days). The secondary biodegradation of C₁₂LAS was also monitored. C₁₂LAS external isomers, which are predominant, are preferentially degraded by successive β-oxidations, generating significant amounts of external even isomers of sulfophenylcarboxylic acid (SPC) (mainly 2,3ΦC_4,6SPCs). In ontrast, internal isomers are converted into internal odd isomers of SPC (mostly 4,5ΦC_5,7SPCs) by ω-oxidation followed by α-oxidation and/or β-oxidations.     

Linear alkylbenzene sulfonates in indoor floor dust

A method was developed to analyse linear alkylbenzene sulfonates (C10-C13 LAS) in vacuumed floor dust in office buildings by the use of HPLC chromatography. Floor dust was sampled with a specially designed vacuum cleaner and fractionated into fibres and particles. The content of LAS in the particle fraction of floor dust sampled from seven different public buildings varied between 34 microg LAS g(-1) dust and 1,500 microg LAS g(-1) dust, while the content of the fibre fractions was generally higher with up to 3,500 microg LAS g(-1) dust. The use of a cleaning agent with LAS resulted in increases approximately 30% of the amount of LAS in the floor dust after floor wash relative to just before floor wash. However, the most important source of LAS in the indoor floor dust appeared to be residues of detergent in clothing. Thus, a newly washed shirt contained 2,960 microg LAS g(-1) clothing. The analysis of the office dust samples indicated that LAS (and probably other detergents) might be of importance for the indoor environment.     

Levels Of Linear Alkylbenzenesulfonates (LAS) In Sediments Of The Berre Lagoon (FRANCE)

A method is described to extract, concentrate and determine trace levels of linear alkylbenzenesulfonates (LAS) (a major anionic surfactant) from sediment samples. It consists of an ultrasonic extraction, followed by clean up and enrichment with C18 mini-columns cartridges and determination by HPLC. Both efficiency and accuracy of the method are high, i.e. mean recovery of 85% and repeatability of 2.8% relative standard deviation for five-replicate LAS analyses. The spatial distribution of LAS and their composition of homologues in sediments of the Berre lagoon, the widest lagoon of the Mediterranean littoral, have been studied. The levels of total LAS in sediments range from 0.21 to 5.00?mg=g (dry weight). Results show that LAS principally associated with solids in suspension, and originating from industrial and urban wastewaters, are principally discharged into the Arc and Cadière Rivers then decant in the mouths of these rivers. The maximum concentrations have been monitored in three zones of the site: the Bolmon lagoon, the Vaine lagoon and the northeast part of the Berre lagoon. The distribution of the LAS homologues in the sediments is not the same as that of the commercial LAS. A great percentage of C13-LAS has been observed (>50%).     

The behavior of polar aromatic sulfonates during drinking water production: a case study on sulfophenyl carboxylates in two European waterworks

First investigations are reported on the efficiency of individual purification steps at two waterworks to eliminate sulfophenyl carboxylates (SPC) originating from biodegradation of linear alkylbenzene sulfonate surfactant. The average SPC concentrations in the waters taken from the Llobregat river, Spain and the Rhine river, Germany amounted to 5.0 and 1.8 microg L(-1), respectively. In the Spanish waterworks, neither prechlorination nor flocculation followed by rapid sand filtration had an impact. After ozonation, granular activated carbon filtration, and final chlorination the SPC level was about 2 microg L(-1) in such processed drinking water. In the German waterworks already the rapid sand filtration diminished the SPC concentration by >85%. Subsequent subsoil passage resulted only in a slight elimination, but once again a slow sand filtration prior to the closing chlorination substantially removed the polar micro-pollutants down to a level of <0.05 microg L(-1) SPC.     

A paleolimnological perspective on industrial-era metal pollution in the central Andes, Peru

To date, few studies have investigated the environmental legacy associated with industrialization in the South American Andes. Here, we present an environmental archive of industrial pollution from (210)Pb-dated lake cores recovered from Laguna Chipian, located near the Cerro de Pasco metallurgical region and Laguna Pirhuacocha, located near the Morococha mining region and the La Oroya smelting complex. At Laguna Chipian, trace metal concentrations increase beginning ~1900 AD, coincident with the construction of the central Peruvian railway, and the rapid industrial development of the Cerro de Pasco region. Trace metal concentrations and fluxes peak during the 1950s before subsequently declining up-core (though remaining well above background levels). While Colonial mining and smelting operations are known to have occurred at Cerro de Pasco since at least 1630 AD, our sediment record preserves no associated metal deposition. Based on our (14)C and (210)Pb data, we suggest that this is due to a depositional hiatus, rather than a lack of regional Colonial pollution. At Laguna Pirhuacocha, industrial trace metal deposition first begins ~1925 AD, rapidly increasing after ~1950 AD and peaking during either the 1970s or 1990s. Trace metal concentrations from these lakes are comparable to some of the most polluted lakes in North America and Europe. There appears to be little diagenetic alteration of the trace metal record at either lake, the exception being arsenic (As) accumulation at Laguna Pirhuacocha. There, a correlation between As and the redox-sensitive element manganese (Mn) suggests that the sedimentary As burden is undergoing diagenetic migration towards the sediment-water interface. This mobility has contributed to surface sediment As concentrations in excess of 1100 microg g(-1). The results presented here chronicle a rapidly changing Andean environment, and highlight a need for future research in the rate and magnitude of atmospheric metal pollution.     

Mineralization of alkylbenzenesulfonates in water by means of contact glow discharge electrolysis

Mineralization of aqueous alkylbenzenesulfonates (ABS) was investigated by means of contact glow discharge electrolysis (CGDE). Toluenesulfonic and dodecylbenzenesulfonic acids in a neutral phosphate buffer solution were smoothly degraded and eventually converted to inorganic carbon and sulfate ion when CGDE was conducted under the applied DC voltage of 500 V and current of ca. 90 mA. As the intermediate products, some phenolic compounds were detected as well as carboxylic acids such as oxalate, formate and so on. It was demonstrated that the decay of ABS followed the first-order rate law. Based on the detailed analysis of the hydroxylation products and kinetic consideration, it was assumed that hydroxyl radicals would play a crucial role in the oxidative degradation of aqueous ABS. The features of CGDE as a tool for the removal of organic pollutants in water were discussed in comparison with other physicochemical methods.     

Simultaneous determination of alkylbenzenesulfonates and dialkyltetralinsulfonates in water by liquid chromatography

A previous method based upon Liquid Chromatography (HPLC) with fluorometric detection for determining linear alkylbenzenesulfonates (LAS) in aqueous environmental samples has been modified for extending it to the monitoring of dialkyltetralinsulfonates (DATS). DATS are reaction byproducts of LAS surfactant synthesis. 10, 100, 200, 1000 ml of respectively untreated sewage, treated one, riverwater and groundwater samples have been extracted by a 0.5-g Graphitized Carbon Black (GCB) cartridge. After sample extraction, co-extracted basic, neutral and weakly acidic compounds have been washed out by a formic acid containing solvent system. DATS and LAS have been then reextracted by passing through the cartridge a basified organic eluant mixture. After solvent removal and residue reconstitution by a suitable solvent system, the subfractionation of the analytes have been achieved by chromatographing them on a C-8 reverse-phase HPLC column. Recovery studies have shown that DATS have been quantitatively extracted by the GCB cartridge. By this procedure, the concentrations in water of DATS entering and leaving two sewage treatment plants in Rome have been monthly monitored over 1 year. With respect to LAS, the higher resistance to biodegradation of DATS has been demonstrated by comparative biodegradation tests. Analysis of a sewage-contaminated groundwater sample has shown that, although DATS are minor components in LAS formulations, the concentration of the former was even higher than that of the latter, with C₁₀ DATS being the most abundant species.     

HPLC detection of linear alkylbenzenesulfonates surfactants (LAS) in marine sediments of the urban sewage area of Cortiou (Marseille,France)

An improved selective method for determining linear alkylbenzenesulfonates surfactants (LASs) in marine sediments using solid‐phase extraction and RP‐HPLC with UV detection is described. The complete analytical method is used on surface sediments from the creek of Cortiou, France. This site is affected by the sewage from the urban area of Marseille. The total LAS concentrations in the sediment range from 12.19?µg/g near the existing outlet to 0.47?µg/g beyond Maire Island. The flux of pollution provided by the outfall is preferentially oriented from east to west by the Liguro‐Provençal current. The significant values are mainly confined on a perimeter of 2.5?km around the outfall. The particule size observations concerning the sediments show that oxygenated sandy zones, where eliminating mechanisms (desorption, biodegradation) particularly occur, are mainly located on the Chèvres plateau and around Jarre, Plane and Riou Islands.     

Monitoring anionic surfactants at a sea outfall, Halifax Harbour, Canada

Anionic surfactants enter the coastal water via untreated sea outfall discharges. A concentration range between 1.0 and 200 μg l⁻¹ can be found in polluted areas. The highest concentration being detected near the point source. In Halifax Harbour, high concentrations of surfactants are associated with the presence of rising plumes. Wind and tidal currents can affect both the spreading of these compounds and the waste field. Under certain circumstances, anionic surfactants may be used as waste effluent tracers but in combination with other parameters.     

Air cargo services in Asian industrialising economies: Electronics manufacturers and the strategic use of advanced producer services

The use of advanced producer services is critical to manufacturing firms in industrialising economies, but most research on such services has been situated in wealthy post-industrial economies. We examine the use of one class of advanced producer services - those provided by the air cargo industry - by manufacturers in Southeast Asia. The air cargo industry has grown rapidly in this region and plays an increasingly important intra- and interregional integrative role. We are interested specifically in the demand for knowledge-intensive advanced air cargo services, which include for instance time-definite express services, by electronics manufacturers in Singapore, Malaysia and the Philippines. Employing several analytical approaches, we find that demand for advanced air cargo services is related to the degree to which a firm's operations are knowledge-intensive, its size, and the scope of its internationalisation.Received: 4 June 2002, Accepted: 12 November 2002, JEL Classification: L63, L93, N75We gratefully acknowledge funding provided by the National Science Foundation, Geography and Regional Science Program for ?Air Cargo Services and Competitive Advantage in Industrialising Economies? under BCS 0078734 (TRL) and BCS 0078621 (JTB). We wish to thank our colleagues in Malaysia: Professor Morshidi Sirat, Dr Hassan Naziri Khalid, and Mohamad Haron Harashid, School of Humanities, Universiti Sains Malaysia, Penang; and in the Philippines: Daniel Mabazza and Jonas Gaffud, Department of Geography, U of Philippines, Diliman, Quezon City. Joshua Lepawsky and Brian Zacho provided invaluable research assistance during the fieldwork and with the subsequent analyses.     

Selection and evaluation of adsorbents for the removal of anionic surfactants from laundry rinsing water

Low-cost adsorbents were tested to remove anionic surfactants from laundry rinsing water to allow re-use of water. Adsorbents were selected corresponding to the different surfactant adsorption mechanisms. Equilibrium adsorption studies of linear alkyl benzene sulfonate (LAS) show that ionic interaction results in a high maximum adsorption capacity on positively charged adsorbents of 0.6-1.7 gLAS/g. Non-ionic interactions, such as hydrophobic interactions of LAS with non-ionic resins or activated carbons, result in a lower adsorption capacity of 0.02-0.6 gLAS/g. Negatively charged materials, such as cation exchange resins or bentonite clay, have negligible adsorption capacities for LAS. Similar results are obtained for alpha olefin sulfonate (AOS). Cost comparison of different adsorbents shows that an inorganic anion exchange material (layered double hydroxide) and activated carbons are the most cost-effective materials in terms of the amount of surfactant adsorbed per dollar worth of adsorbent.     

粤港澳大湾区入境旅游发展差异及其影响因素

采取构建旅游发展指数、基尼系数、GIS方法和市场集中度、熵值法等研究方法，对粤港澳大湾区入境旅游发展水平及客源结构差异的时空演变特征进行刻画，研究发现：①2000年至今，粤港澳大湾区入境旅游发展经过培育阶段（2000~2003年）、快速发展阶段（2004~2008年）和新常态阶段（2009~2017年）3个阶段；②入境旅游区域差异虽有所减小，但持续呈现以香港、澳门为第一层级，深圳、广州为第二层级，其余7市位于第三、四层级的多级格局；③在客源结构方面，香港市场多样性最强，客源结构多元且受距离限制小；澳门的市场多样性不断下降，客源集中在东亚、东南亚等近程市场；珠三角市场稳定性较强；④9市2区在城市功能和地位上的差异是入境旅游呈现多级格局且客源结构存在差异的主要原因。     

The Use of Economic Instruments for Water Management in Selected EU Member Countries

The use of economic instruments for environmental management is being encouraged by the European Commission for the management of water abstractions and effluent discharges. Economic instruments are being applied increasingly by EU Member States to complement the traditional 'command and control'approach, based on the licensing system. However, the design and the purpose of the charging schemes, and the levels of charges raised in the different EU Member States, vary widely.
This paper (a) discusses the use of abstraction and effluent charges applied in France, Germany, The Netherlands, and England & Wales, (b) assesses the impact of the schemes on water abstractions and effluent discharges, and (c) evaluates the feasibility of the application of incentive charging schemes.