Contamination Sources



Waste & Pollution

As the urban population is growing globally and this effect is coupled with increasing consumption, waste management has become one of the most serious environmental challenges in urban areas, with adverse effects on the quality of life, human health, environmental and natural resources, and economic and social development. It is important to know the composition of a load of waste before it is send to landfill. On the other hand, only through developing an intimate understanding of the chemistry of organic chemicals can their eventual remediation be realized.

TOC in waste

Landfills are classified according to whether they can accept hazardous, non-hazardous or inert wastes. In waste management, TOC acts as a measure for contamination with organic compounds and is also used to perform quality control (QC) checks on industrial materials such as fly ash, cement, and kaolin. Also if you evaluate the recycling of residues – there is no way around TOC.

Temperature-dependent carbon fractions

The differentiation between two carbon fractions (TIC and TOC) could be insufficient as biologically inactive, residual oxidizable carbon is determined in the same fraction as TOC. When evaluating solid wastes, elemental carbon (ROC) should be determined separately, since there is no need to restrict the load of ROC to landfills. An alternative method for the determination of elemental carbon is temperature ramping as elemental carbon requires higher combustion temperatures compared to organically-bound carbon, which is realized by the soli TOC® cube.

Sources and fate of contamination

Stable isotope analysis has the power to deliver unparalleled insight into the complex interactions of organic pollutants in the environment. It can elucidate the often complex sources and fates of pollutant chemicals on land and at sea, aiding remediation strategy and shaping waste and resource management policy for protection of the environment. Developing our understanding of these processes aids our stewardship of the natural world to ensure that future generations enjoy the same wonders that we do today.

Waste & Pollution publications using our instruments

Our customers use our instruments to do some amazing research in the waste and pollution application field. To show you how they perform their research and how they use our IRMS instruments, we have collected a range of peer-reviewed publications which cite our products. You can find the citations below and then follow the links to the publishing journal should you wish to download the publication.

If you would like to investigate our available citations in more detail, or email the citation list to yourself or your colleagues then take a look at our full citation database.

84 results:

Using stable isotope analysis to discriminate gasoline on the basis of its origin.
Rapid communications in mass spectrometry : RCM (2012)
Su-Young Heo, Woo-Jin Shin, Sin-Woo Lee, Yeon-Sik Bong, Kwang-Sik Lee

RATIONALE: Leakage of gasoline and diesel from underground tanks has led to a severe environmental problem in many countries. Tracing the production origin of gasoline and diesel is required to enable the development of dispute resolution and appropriate remediation strategies for the oil-contaminated sites. METHODS: We investigated the bulk and compound-specific isotopic compositions of gasoline produced by four oil companies in South Korea: S-Oil, SK, GS and Hyundai. The relative abundance of several compounds in gasoline was determined by the peak height of the major ion (m/z 44). RESULTS: The δ(13)C(Bulk) and δD(Bulk) values of gasoline produced by S-Oil were significantly different from those of SK, GS and Hyundai. In particular, the compound-specific isotopic value (δ(13)C(CSIA)) of methyl tert-butyl ether (MTBE) in S-Oil gasoline was significantly lower than that of gasoline produced by other oil companies. The abundance of several compounds in gasoline, such as n-pentane, MTBE, n-hexane, toluene, ethylbenzene and o-xylene, differed widely among gasoline from different oil companies. CONCLUSIONS: This study shows that gasoline can be forensically discriminated according to the oil company responsible for its manufacture using stable isotope analysis combined with multivariate statistical analysis.
Tags: carbon , hydrogen , crim , poll , elem , gaschrom

Carbon and chlorine isotope ratios of chlorinated ethenes migrating through a thick unsaturated zone of a sandy aquifer.
Environmental science & technology (2011)
Daniel Hunkeler, Ramon Aravena, Orfan Shouakar-Stash, Noam Weisbrod, Ahmed Nasser, Lior Netzer, Daniel Ronen

Compound-specific isotope analysis (CSIA) can potentially be used to relate vapor phase contamination by volatile organic compounds (VOCs) to their subsurface sources. This field and modeling study investigated how isotope ratios evolve during migration of gaseous chlorinated ethenes across a 18 m thick unsaturated zone of a sandy coastal plain aquifer. At the site, high concentrations of tetrachloroethene (PCE up to 380 μg/L), trichloroethene (TCE up to 31,600 μg/L), and cis-1,2-dichloroethene (cDCE up to 680 μg/L) were detected in groundwater. Chlorinated ethene concentrations were highest at the water table and steadily decreased upward toward the land surface and downward below the water table. Although isotopologues have different diffusion coefficients, constant carbon and chlorine isotope ratios were observed throughout the unsaturated zone, which corresponded to the isotope ratios measured at the water table. In the saturated zone, TCE became increasingly depleted along a concentration gradient, possibly due to isotope fractionation associated with aqueous phase diffusion. These results indicate that carbon and chlorine isotopes can be used to link vapor phase contamination to their source even if extensive migration of the vapors occurs. However, the numerical model revealed that constant isotope ratios are only expected for systems close to steady state.

Stable carbon isotope evidence for nitrogenous fertilizer impact on carbonate weathering in a small agricultural watershed.
Rapid communications in mass spectrometry : RCM (2011)
F Brunet, C Potot, A Probst, J-L Probst

The isotopic signature of Dissolved Inorganic Carbon (DIC), δ(13)C(DIC), has been investigated in the surface waters of a small agricultural catchment on calcareous substratum, Montoussé, located at Auradé (south-west France). The Montoussé catchment is subjected to intense farming (wheat/sunflower rotation) and a moderated application of nitrogenous fertilizers. During the nitrification of the NH(4)(+), supplied by fertilization, nitrate and H(+) ions are produced in the soil. This anthropogenic acidity is combined with the natural acidity due to carbonic acid in weathering processes. From an isotopic point of view, with 'natural weathering', using carbonic acid, δ(13)C(DIC) is intermediate between the δ(13)C of soil CO(2) produced by organic matter oxidation and that of the carbonate rocks, while it has the same value as the carbonates when carbonic acid is substituted by another acid like nitric acid derived from nitrogen fertilizer. The δ(13)C(DIC) values range from -17.1‰ to -10.7‰ in Montoussé stream waters. We also measured the δ(13)C of calcareous molassic deposits (average -7.9‰) and of soil organic carbon (between -24.1‰ and -26‰) to identify the different sources of DIC and to estimate their contribution. The δ(13) C(DIC) value indicates that weathering largely follows the carbonic acid pathway at the springs (sources of the stream). At the outlet of the basin, H(+) ions, produced during the nitrification of N-fertilizer, also contribute to weathering, especially during flood events. This result is illustrated by the relationship between δ(13)C(DIC) and the molar ratio NO(3)(-)/(Ca(2+) + Mg(2+)). Consequently, when the contribution of nitrate increases, the δ(13)C(DIC) increases towards the calcareous end-member. This new isotopic result provides evidence for the direct influence of nitrogen fertilizer inputs on weathering, CO(2) consumption and base cation leaching and confirms previous results obtained using the chemistry of the major ions present in the field, and in soil column experiments.
Tags: carbon , poll , gashead

Geochemistry and arsenic behaviour in groundwater resources of the Pannonian Basin (Hungary and Romania)
Applied Geochemistry (2011)
Helen a L Rowland, Enoma O. Omoregie, Romain Millot, Cristina Jimenez, Jasmin Mertens, Calin Baciu, Stephan J. Hug, Michael Berg

Groundwater resources in the Pannonian Basin (Hungary, Romania, Croatia and Serbia) are known to contain elevated naturally occurring As. Published estimates suggest nearly 500,000 people are exposed to levels greater than the EU maximum admissible concentration of 10μg/L in their drinking water, making it the largest area so affected in Europe. In this study, a variety of groundwaters were collected from Romania and Hungary to elucidate the general geochemistry and identify processes controlling As behaviour. Concentrations ranged from <0.5 to 240μg/L As(tot), with As predominantly in the reduced As(III) form. Using cluster analysis, four main groups of water were identified. Two groups (1 and 2) showed characteristics of water originating from reducing aquifers of the area with both groups having similar ranges of Fe concentrations, indicating that Fe-reduction occurs in both groups. However, As levels and other redox characteristics were very different. Group 1, indicative of waters dominated by methanogenesis contained high As levels (23-208μg/L, mean 123μg/L), with group 2 indicative of waters dominated by SO42--reduction containing low As levels (<0.5-58μg/L, mean 11.5μg/L). The remaining two groups were influenced either by (i) geothermal and saline or (ii) surface contamination and rain water inputs. Near absence of As in these groups, combined with positive correlations between δ7Li (an indicator of geothermal inputs) and As(tot) in geothermal/saline influenced waters indicate that elevated As is not from an external input, but is released due to an in-aquifer process. Geochemical reasoning, therefore, implies As mobilisation is controlled by redox processes, most likely microbially mediated reductive dissolution of As bearing Fe-oxides, known to occur in sediments from the area. More important is an overlying retention mechanism determined by the presence or absence of SO42-Ongoing SO42--reduction will release S2-, removing As from solution either by the formation of As-sulfides, or from sorption onto Fe-sulfide phases. In methanogenic waters, As released by reductive dissolution is not removed from solution and can rise to the high levels observed. Levels of organic C are thought to be the ultimate control on the redox conditions in these 2 groups. High levels of organic C (as found in group 1) would quickly exhaust any SO42- present in the waters, driving the system to methanogenesis and subsequent high levels of As. Group 2 has much lower concentrations of organic C and so SO42- is not exhausted. Therefore, As levels in waters of the Pannonian Basin are controlled not by release but by retention mechanisms, ultimately controlled by levels of TOC and SO42- in the waters.δD and δ18O analysis showed that groundwaters containing elevated As dated mostly from the last ice-age, and are sourced from Late Pliocene to Quaternary aquifers. The importance of TOC and retention capabilities of SO42--reduction have only previously been suggested for recent (Holocene) sediments and groundwater, most notably those in SE Asia as these are the most likely to contain the right combination of factors to drive the system to a redox situation leading to high aqueous As concentrations. In contrast, it is shown here that a much older system containing As bearing Fe-oxides, also has the potential to produce elevated levels of As if the TOC is suitable for the microbial population to drive the system to the correct redox situation and SO42- is either absent or wholly consumed. © 2010 Elsevier Ltd.

δ 13 C and δD measurements of volatile organic compounds in a variety of emissions by thermal desorption compound specific isotope analysis t
Atmospheric Environment (2011)
Christiane Vitzthum von Eckstaedt, Kliti Grice, Marisa Ioppolo-Armanios, Mark Jones

Compound specific isotope analysis (CSIA) is becoming more widely accepted as a tool for determining the sources of contaminants and monitoring their transport and fate in the environment. However, measuring ??D of volatile organic compounds (VOCs) in atmospheric samples is still underexplored. The present study applies thermal desorption-gas chromatography-isotope ratio mass spectrometry (TD-GC-irMS) for the first time to measure stable hydrogen isotope analyses of VOCs in an alumina refinery emission. ?? 13C data is also collected. A sampling train was designed using TenaxTA as the adsorbent material to gain reliable and reproducible results for CSIA. ?? 13C values for VOCs (C 6-C 14) ranged from -22 to -31???, which is similar to ?? 13C value range reported for naturally occurring components. The ??D values (21 to -137???) in this study were consistently more enriched in D compared to ??D values of VOCs previously reported making the ?? values of VOCs in the industrial stack unique. Therefore ??D analysis may provide a means for tracking VOCs in atmospheric samples. ?? 2011 Elsevier Ltd.
Tags: carbon , hydrogen , poll , gaschrom

Stable Isotope Characterization of Ammonium Metavanadate
Alan M Volpe, Michael J Singleton

This paper describes hydrogen (2H/1H), nitrogen (15N/14N), and oxygen (18O/16O) isotopic characteriza- tion of ammonium metavanadate (NH4VO3), a toxic industrial chemical (TIC). We analyzed nineteen high purity compounds obtained from nine suppliers, which show large ranges in trivariate stable isotope compositions, nearly 100-fold greater than analytical uncertainty. Covariation between d2H and d15N values indicates these ratios can be used to trace ammonia compounds, which are critical for the industrial purification of vanadyl ions and precipitation of ammoniummetavanadate crystals. d2H and d18O plot far from the Meteoric Water Line (MWL), and suggest materials and industrial processing may lead to decoupling of H and O isotopes. We show how stable isotope characterization is a valuable forensic tool that discriminates between NH4VO3 samples due to differences in source materials, modes of production, and facility location
Tags: carbon , nitrogen , crim , poll , elem

The stable isotopic composition (37Cl/35Cl) of dissolved chloride in rainwater
Applied Geochemistry (2010)
Geoff Koehler, Leonard I. Wassenaar

The stable isotopic composition of dissolved Cl- in rainwater was measured from a coastal and an interior location in eastern Canada. At the interior Bonner Lake, Ontario, site the δ37Cl values of dissolved Cl- in precipitation ranged from −3.5‰ to −1.2‰ (SMOC) with an amount-weighted annual average of −2.3‰. At the coastal site, Bay D’Espoir, Newfoundland, δ37Cl values of dissolved Cl- values ranged from −3.1‰ to 0.0‰ with an amount-weighted annual average of −1.3‰. These negative δ37Cl values provide evidence that atmospheric HCl is 37Cl depleted, presumably from acidification of sea-salt aerosols. Accordingly, dissolved Cl- in the headwaters of two montane rivers in Western Canada had similarly depleted δ37Cl values. These results have implications to the interpretation of the isotopic compositions of dissolved Cl- in surface waters, formation fluids, and groundwaters.

The stable-carbon kinetic isotope effects of the reactions of isoprene, methacrolein, and methyl vinyl ketone with ozone in the gas phase
Atmospheric Environment (2008)
Richard Iannone, Ralf Koppmann, Jochen Rudolph

The stable-carbon kinetic isotope effects (KIEs) for the gas-phase reactions of isoprene, methacrolein (MACR), and methyl vinyl ketone (MVK) with ozone were studied in a 25 L reaction chamber at 298?2 K and ambient pressure. The time dependence of both the stable-carbon isotope ratios and the concentrations was determined using a gas chroma- tography combustion isotope ratio mass spectrometry (GCC–IRMS) system. The volatile organic compounds (VOCs) used in the KIE experiments had natural-abundance isotopic composition thus KIE data obtained from these experiments can be directly applied to atmospheric studies of isoprene chemistry. All 13C/12C KIEs reported herein are as per mille 3 values, where 3¼(KIE?1)?1000&, and KIE¼k12/k13. The following average stable- carbon KIEs were obtained: (8.40?0.11)& (isoprene), (8.38?0.42)& (MACR), and (8.01?0.07)&(MVK). The stable-carbon KIE values of three 1-alkenes, which were used as reference compounds for relative rate experiments, were also determined: (5.48?0.09)& (1-heptene), (4.67?0.17)&(1-octene), and (4.59?0.56)&(1-nonene). The 3 values for the reactions of isoprene and 1-heptene with ozone agree with measurements in a previous study [Iannone, R., Anderson, R.S., Rudolph, J., Huang, L., Ernst, D., 2003. The carbon kinetic isotope effects of ozone–alkene reactions in the gas-phase and the impact of ozone reac- tions on the stable carbon isotope ratio of alkenes in the atmosphere. Geophysical Research Letters 30, 1684, doi: 10.1029/2003GL017221.], but the values presented here have a substantially improved accuracy. The 3 values for 1-octene and 1-nonene reactions with ozone have not been measured before and closely follow the 1/NC dependence (where NC represents the number of carbon atoms in the alkene) derived in the aforementioned study. MACR and MVK had 3 values that were somewhat below the expected range of values predicted by the 1/NC dependence found for alkenes.

A technique for atmospheric measurements of stable carbon isotope ratios of isoprene, methacrolein, and methyl vinyl ketone
Journal of Atmospheric Chemistry (2007)
R. Iannone, R. Koppmann, J. Rudolph

A technique was developed to measure stable carbon isotope ratios (13C/12C) of light volatile organic compounds (VOCs) such as isoprene, methacrolein (MACR) and methyl vinyl ketone (MVK) using gas chromatography combustion isotope ratio mass spectrometry (GCC-IRMS). An automated sampling and cryofocussing system allowed for the extraction of VOCs from air samples of up to 140 L of air collected over 3 h, and the subsequent 13C/12C analysis of the VOCs by GCC-IRMS. Chromatography using selective transfer between two columns was used to improve the separation for selected compounds, increasing peak resolution and attaining less noisy baselines. Still, some target compounds could not be completely separated from co-eluting peaks. To reduce the bias of isotope ratio determinations, which can result from incomplete peak resolution, a peak-fitting procedure has been developed. In cases of overlapping peaks or substantial baseline drift, this peak fitting allows more accurate determination of isotope ratios than conventional integration schemes. Comparisons between off-line IRMS measurements and a peak-evaluation procedure using a prepared VOC gas-phase standard show that isotope ratios derived from large (>1 ng of carbon per peak) and well-resolved peaks have a reproducibility of ±0.3‰. With smaller masses in the range of 0.1–1 ng of carbon, reproducibility decreased to ±(0.5– 0.8)‰. For a 140 L sample of air, such small masses of carbon correspond to mixing ratios in the low pptV range. The developed measurement technique was applied to a small set of ambient air samples taken during hot, sunny periods from late May to early August, 2005, at Forschungszentrum Jülich, Germany, a semi-rural area. The range of δ13C values determined for isoprene, benzene, and toluene are consistent with those reported in the literature. GCC-IRMS results of δ13C for ambient samples of isoprene, MACR, and MVK, measured at mixing ratios of 15–280 pptV, are presented and discussed

Compound-specific chlorine isotope ratios of TCE, PCE and DCE isomers by direct injection using CF-IRMS
Applied Geochemistry (2006)
Orfan Shouakar-Stash, Robert J. Drimmie, Min Zhang, Shaun K. Frape

A method for determining compound-specific Cl isotopic compositions (d37Cl) was developed for tetrachloroethene (PCE), trichloroethene (TCE), cis-dichloroethene (cis-DCE), trans-dichloroethene (trans-DCE) and 1,1-dichloroethene (1,1-DCE). The isotope ratio mass spectrometry (IRMS) used in this study has nine collectors, including two for m/z 50 and 52 (CH3Cl) and two for m/z 94 and 96 (CH3Br). The development of this method is based on the fact that fragments with mass ratios of 94/96, 95/97 and 96/98 are produced from PCE, TCE and DCE isomers during ion bombardment in the source of a mass spectrometer. Using continuous flow isotope ratio mass spectrometry coupled with gas chromatog- raphy (GC–CF-IRMS), it is possible to separate these compounds on-line and directly measure the Cl isotopic ratios of the fragments with the specific mass ratios. Both pure phase and aqueous samples were used for Cl isotopic analysis. For pure phase samples, a vapour phase of the chlorinated ethenes was injected directly into the GC, whereas the solid phase micro extraction (SPME) method was used to extract these compounds from aqueous solutions. The precisions of this analytical technique were ±0.12&(1r, n = 30), ±0.06&(1r, n = 30), and ±0.08&(1r, n = 15) for PCE, TCE and DCE isomers, respectively. The limits of quantification (LOQ) for analyzing Cl isotopic composition in aqueous solutions were 20, 5, and 5 lg/L for PCE, TCE and DCE isomers, respectively. This corresponds to 6–9 nano-mole of Cl, which is approximately 80 times lower than the most sensitive exist- ing method. Compared to methods previously available, this new development offers the following advantages: (1) The much lower LOQ make it possible to extract these compounds directly from aqueous solutions using SPME without pre-concentration; (2) The linking of a GC with an IRMS eliminates off-line separation; and (3) Because the fragments used for isotopic ratio measurement are produced during ion bombardment in the mass spectrometer, there is no need to convert chlorinated ethenes to methyl chloride. As a result, this technique greatly enhances the efficiency for isotopic analysis by eliminating procedures for pre-concentration, off-line separation and sample preparation. In addition, it also reduces the potential for isotopic fractionation introduced during these procedures. Compound-specific Cl stable isotope analysis can be used as a tool to study the sources of organic contaminants in groundwater and their behaviour in the subsurface environments. It may also assist in understanding processes such as transport, mixing, and degradation reactions