Publications by authors named "Hendrik Van De Weghe"

8 Publications

  • Page 1 of 1

Decreased mitochondrial DNA content in association with exposure to polycyclic aromatic hydrocarbons in house dust during wintertime: from a population enquiry to cell culture.

PLoS One 2013 3;8(5):e63208. Epub 2013 May 3.

Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium.

Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental pollutants that are formed in combustion processes. At the cellular level, exposure to PAHs causes oxidative stress and/or some of it congeners bind to DNA, which may interact with mitochondrial function. However, the influence of these pollutants on mitochondrial DNA (mtDNA) content remains largely unknown. We determined whether indoor exposure to PAHs is associated with mitochondrial damage as represented by blood mtDNA content. Blood mtDNA content (ratio mitochondrial/nuclear DNA copy number) was determined by real-time qPCR in 46 persons, both in winter and summer. Indoor PAH exposure was estimated by measuring PAHs in sedimented house dust, including 6 volatile PAHs and 8 non-volatile PAHs. Biomarkers of oxidative stress at the level of DNA and lipid peroxidation were measured. In addition to the epidemiologic enquiry, we exposed human TK6 cells during 24 h at various concentrations (range: 0 to 500 µM) of benzo(a)pyrene and determined mtDNA content. Mean blood mtDNA content averaged (± SD) 0.95 ± 0.185. The median PAH content amounted 554.1 ng/g dust (25(th)-75(th) percentile: 390.7-767.3) and 1385 ng/g dust (25(th)-75(th) percentile: 1000-1980) in winter for volatile and non-volatile PAHs respectively. Independent for gender, age, BMI and the consumption of grilled meat or fish, blood mtDNA content decreased by 9.85% (95% CI: -15.16 to -4.2; p = 0.002) for each doubling of non-volatile PAH content in the house dust in winter. The corresponding estimate for volatile PAHs was -7.3% (95% CI: -13.71 to -0.42; p = 0.04). Measurements of oxidative stress were not correlated with PAH exposure. During summer months no association was found between mtDNA content and PAH concentration. The ability of benzo(a)pyrene (range 0 µM to 500 µM) to lower mtDNA content was confirmed in vitro in human TK6 cells. Based on these findings, mtDNA content can be a target of PAH toxicity in humans.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0063208PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3643917PMC
November 2013

Combining HPLC-GCXGC, GCXGC/ToF-MS, and selected ecotoxicity assays for detailed monitoring of petroleum hydrocarbon degradation in soil and leaching water.

Environ Sci Technol 2009 Oct;43(20):7651-7

Flemish Institute for Technological Research (VITO), Mol, Belgium.

HPLC-GCXGC/FID (high-performance liquid chromatography followed by comprehensive two-dimensional gas chromatography with flame-ionization detection) and GCXGC/ToF-MS (comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry) were used to study the biodegradation of petroleum hydrocarbons in soil microcosms during 20 weeks. Two soils were studied: one spiked with fresh diesel and one field sample containing weathered diesel-like oil. Nutrient amended and unamended samples were included. Total petroleum hydrocarbon (TPH) levels in spiked soil decreased from 15,000 to 7,500 mg/kg d.m. and from 12,0O0 to 4,000 mg/kg d.m. in the field soil. Linear alkanes and aromatic hydrocarbons were better biodegradable (>60% degraded) than iso-alkanes; cycloalkanes were least degradable (<40%). Aromatic hydrocarbons up to three rings showed better degradability than n-alkanes. GCXGC/ToF-MS analysis of leaching water showed that initially various oxygenated hydrocarbons were produced. Compound peaks seemed to move up and rightward in the GCXGC chromatograms, indicating that more polar and heavier compounds were formed as biodegradation proceeded. Nutrient amendment can increase TPH removal rates, but had adverse effects on ecotoxicity and leaching potential in our experiment This was explained by observed shifts in the soil microbial community. Ecotoxicity assays showed that residual TPH still inhibited cress (Lepidium sativum) seed germination, but the leaching water was no longer toxic toward luminescent bacteria (Vibrio fischeri).
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http://dx.doi.org/10.1021/es9015603DOI Listing
October 2009

Estimation of ecotoxicity of petroleum hydrocarbon mixtures in soil based on HPLC-GCXGC analysis.

Chemosphere 2009 Dec 30;77(11):1508-13. Epub 2009 Oct 30.

Flemish Institute for Technological Research (VITO), Boeretang 200, B-2400 Mol, Belgium.

Detailed HPLC-GCXGC/FID (high performance liquid chromatography followed by comprehensive two-dimensional gas chromatography with flame-ionization detection) analysis of oil-contaminated soils was performed to interpret results of selected acute ecotoxicity assays. For the five ecotoxicity assays tested, plant seed germination and Microtox were selected as most sensitive for evaluating ecotoxicity of the oil in the soil phase and in the leaching water, respectively. The measured toxicity for cress when testing the soil samples did not correspond to TPH concentration in the soil. A detailed chemical composition analysis of the oil contamination using HPLC-GCXGC/FID allows to better predict the ecotoxicological risk and leaching potential of petroleum hydrocarbons in soil. Cress biomass production per plant was well correlated to the total aromatic hydrocarbon concentration (R2=0.79, n=6), while cress seed germination was correlated (R2=0.82, n=6) with total concentration of "highly water-soluble aromatic hydrocarbons" (HSaromatics). The observed ecotoxicity of the leaching water for Microtox-bacteria related well to calculated (based on the HPLC-GCXGC/FID results) petroleum hydrocarbon equilibrium concentrations in water.
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http://dx.doi.org/10.1016/j.chemosphere.2009.10.004DOI Listing
December 2009

Organochlorine and heavy metals in newborns: results from the Flemish Environment and Health Survey (FLEHS 2002-2006).

Environ Int 2009 Oct 18;35(7):1015-22. Epub 2009 Jun 18.

Environmental Risk & Health, Toxicology Group, Flemish Institute of Technological Research, 2400 Mol, Belgium.

To collect regional information on internal levels of pollutants in humans in Flanders, 1196 mother-child pairs were systematically recruited in 2002-2003 via 25 maternities across Flanders. Cd, Pb, PCB congeners 118, 170, 138, 153 and 180, p,p'-DDE - a key metabolite of DDT- and hexachlorobenzene (HCB) were measured in cord blood or plasma. Cd was detected in 64% of the samples (geometric mean 0.21 microg/L cord blood). p,p'-DDE (110 ng/g plasma lipids) and Pb (14.7 microg/L blood), were measurable in nearly all samples. The individual PCB congeners could be detected in 40 to 81% of the newborns (138+153+180=64.4 ng/g plasma lipids). HCB (18.9 ng/g plasma lipids) and dioxin-like compounds measured by DR-CALUX(R) (23 pg CALUX-TEQ/g lipids) were above detection limit in more than 75% of the samples. Age and smoking habits of the mothers, did not influence the cord blood Pb and Cd levels. The organochlorines increased 4 to 9% per year of the mother's age (partial R(2)=0.05 to 0.22). Mothers had 2.6% less PCBs in cord blood (partial R(2)=0.02) for each unit increase in pre-pregnancy BMI. Season of delivery, breastfeeding previous children or consumption of local dairy products, were minor determinants. Up to 20% of the variability in organochlorine concentrations was explained by residence area. It was concluded that the place of birth in Flanders is an important determinant of the load of pollutants measured at the start of life. This underlines the validity of human biomonitoring on (relatively) small geographical scale.
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http://dx.doi.org/10.1016/j.envint.2009.05.002DOI Listing
October 2009

Detailed analysis of petroleum hydrocarbon attenuation in biopiles by high-performance liquid chromatography followed by comprehensive two-dimensional gas chromatography.

J Chromatogr A 2009 Feb 6;1216(9):1524-7. Epub 2009 Jan 6.

Flemish Institute for Technological Research (VITO), Boeretang 200, B-2400 Mol, Belgium.

Enhanced bioremediation of petroleum hydrocarbons in two biopiles was quantified by high-performance liquid chromatography (HPLC) followed by comprehensive two-dimensional gas chromatography (GCXGC). The attenuation of 34 defined hydrocarbon classes was calculated by HPLC-GCXGC analysis of representative biopile samples at start-up and after 18 weeks of biopile operation. In general, a-cyclic alkanes were most efficiently removed from the biopiles, followed by monoaromatic hydrocarbons. Cycloalkanes and polycyclic aromatic hydrocarbons (PAHs) were more resistant to degradation. A-cyclic biomarkers farnesane, trimethyl-C13, norpristane, pristane and phytane dropped to only about 10% of their initial concentrations. On the other hand, C29-C31 hopane concentrations remained almost unaltered after 18 weeks of biopile operation, confirming their resistance to biodegradation. They are thus reliable indicators to estimate attenuation potential of petroleum hydrocarbons in biopile processed soils.
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http://dx.doi.org/10.1016/j.chroma.2008.12.087DOI Listing
February 2009

Aqueous solubility calculation for petroleum mixtures in soil using comprehensive two-dimensional gas chromatography analysis data.

J Chromatogr A 2009 Apr 26;1216(14):2873-80. Epub 2008 Aug 26.

Flemish Institute for Technological Research (VITO), Boeretang 200, B-2400 Mol, Belgium.

An assessment of aqueous solubility (leaching potential) of soil contaminations with petroleum hydrocarbons (TPH) is important in the context of the evaluation of (migration) risks and soil/groundwater remediation. Field measurements using monitoring wells often overestimate real TPH concentrations in case of presence of pure oil in the screened interval of the well. This paper presents a method to calculate TPH equilibrium concentrations in groundwater using soil analysis by high-performance liquid chromatography followed by comprehensive two-dimensional gas chromatography (HPLC-GCXGC). The oil in the soil sample is divided into 79 defined hydrocarbon fractions on two GCXGC color plots. To each of these fractions a representative water solubility is assigned. Overall equilibrium water solubility of the non-aqueous phase liquid (NAPL) present in the sample and the water phase's chemical composition (in terms of the 79 fractions defined) are then calculated using Raoult's law. The calculation method was validated using soil spiked with 13 different TPH mixtures and 1 field-contaminated soil. Measured water solubilities using a column recirculation equilibration experiment agreed well to calculated equilibrium concentrations and water phase TPH composition.
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http://dx.doi.org/10.1016/j.chroma.2008.08.072DOI Listing
April 2009

High-performance liquid chromatography fractionation using a silver-modified column followed by two-dimensional comprehensive gas chromatography for detailed group-type characterization of oils and oil pollutions.

J Chromatogr A 2008 Jan 11;1179(1):33-40. Epub 2007 Oct 11.

Flemish Institute for Technological Research (VITO), Boeretang 200, Mol, Belgium.

Successful remediation of oil-contaminated soils relies on a sound preceding characterization of the oil chemical composition and physicochemical properties. Comprehensive two-dimensional gas chromatography with flame ionization detection (GCxGC/FID) is known to be very suitable for the analysis of complex samples such as petroleum hydrocarbons. However, in spite of the high-separation power offered by GCxGC, it fails to completely separate certain hydrocarbon groups in petroleum hydrocarbon mixtures. This hampers a detailed chemical composition assessment which can lead to wrong conclusions on the behaviour of the oil in soil systems, e.g. biological degradability and water solubility. This paper describes a high-performance liquid chromatography (HPLC) system with a silver-modified column as a prefractionation step to GCxGC to improve chemical identification. With HPLC, the petroleum hydrocarbons were baseline separated into a saturated fraction (including alkanes and cycloalkanes) and an unsaturated fraction (including alkenes, aromatic hydrocarbons and heterocyclic components). Each fraction eluted in a small time window limiting the dilution caused by HPLC. The two fractions were collected and quantitatively analyzed with GCxGC/FID. Cold splitless injection of 4 microl was adopted to compensate the dilution caused by the prefractionation step. With oil-spiked soil samples, a good reproducibility was obtained (RSD=3.5%; n=7) and the recovery was satisfactory (87.7%).
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http://dx.doi.org/10.1016/j.chroma.2007.09.085DOI Listing
January 2008

Application of comprehensive two-dimensional gas chromatography for the assessment of oil contaminated soils.

J Chromatogr A 2006 Dec 20;1137(1):91-100. Epub 2006 Oct 20.

VITO, Boeretang 200, B-2400 Mol, Belgium.

A crucial step in the remediation of oil contaminated soils is the characterization of the pollution. Information on the chemical composition is used to assess the toxicity (and thus the need for remediation) and to determine the most appropriate technology for treatment. Mostly these analyses are carried out in routine environmental laboratories using gas chromatography with flame ionization detection (GC/FID) based on a protocol developed by the Total Petroleum Hydrocarbon Criteria Working Group (TPHCWG). In the present study, an alternative method was developed using comprehensive two-dimensional gas chromatography (GCXGC) with FID. Sample preparation was limited to pressurized liquid extraction (PLE), and the analysis was carried out on a commercially available instrument with a conventional column combination (RTX-1/BPX50) and with standard chromatographic software. Compared to the TPH method, the group-types in the GCXGC analysis are chemically better defined and more specific information is obtained especially for the (toxicologically important) aromatic hydrocarbon fraction. Preliminary results indicate that higher recoveries and lower RSDs are obtained with GCXGC, probably because of the less complex sample preparation. Furthermore a data processing method was developed to generate TPH results from GCXGC data; the volatility distribution profiles compared very well with conventional TPH data. The possibility of extracting physicochemical properties directly from the GCXGC chromatogram was briefly explored, but software limitations hindered this promising application.
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http://dx.doi.org/10.1016/j.chroma.2006.10.014DOI Listing
December 2006