Application of gaschromatography ion trap mass-spectrometry with screening of organophosphoreus pesticides in water

Abstract niet beschikbaarIn this work, the utility of gaschromatography-ion mass-spectrometry for the screening on pesticides in water has been studied. Essential for screening purposes is that the presence of compounds of interest can be shown by the method in a relatively rapid and simple but reliable way. The present study has been restricted to the group of organophosphoreus pesticides of which approximately 75 compounds are used in the Netherlands and hence can occur in the environment. Of 62 out of 65 pesticides examined, electron impact and chemical ionization spectra have been obtained and relative retention indices (relative to parathion) have been determined. Detection limits ranged between 50- 500 pg on column for compounds having good GC properties. 500-5000 pg were needed for some compounds having poor GC properties.RIV

Development of an improved method for chemical analysis of isoniazide in serum using pentafluorobenzoyl derivatisation and gaschromatograhphy- negative ion chemical ionization mass spectrometry

This report describes the development of a new method for the analysis of the tuberculostaticum isoniazid in human serum. The Laboratory of Chemotherapy needed a sensitive method for the analysis of this compound, which is also useful for complex matrices (e.g. sera of nephritic patients). The developed method is based on a one-step derivatization of isoniazid with pentafluorobenzoylchloride in buffered alkaline aqueous samples. First, reaction takes place on the azid moiety, followed by an intermolecular rearrangement leading to a stable, non-polar derivative, which is easily extracted (>95%) and has excellent gaschromatographic properties. The reaction is rapic ( 95%) were obtained with strong buffercapacities (1-3 molar) of the sample. For serumsamples, prior proteinprecipitation was necessary in order to obtain similar recoveries as for aqueous standards. The derivative was highly sensitive for negative-ion-chemical-ionization. The detection limit for serum was better than 0.1 mug/ml with sample sizes of 0.5 ml or less.RIV

Investigation of Ambient Air levels of 2, 3, 7, 8-Substituted polychlorinated Dibenzodioxins and Dibenzofurans in the Netherlands. Part I: Method Development

Abstract niet beschikbaarThis report describes the first results of the method development for the measurement of polychlorodibenzene-p-dioxins (PCDDs) and -furans (PCDFs) in the ambient air in the Netherlands with the aim to a better understand of occurrence and dispersion in relation to sources of these compounds. Results will be used for verification/validation of dispersion calculations by use of the dispersion and deposition model (OPS-model). The sampling strategy as well as the development of the analytical procedures for measuring PCDD/F in air will be discussed. Preliminary results indicate that with the present technique extreme low concentrations of PCDD/F can be measured with a reproducability of 20% in ambient air of 5 fg.TEQ.m-3 or higher. In an industrial/urban location in the Netherlands, background concentrations of 15 fg. TEQ.m-3 and immission concentrations of exceeding 80 fg.TEQ.m-3 have been measured.HIMH HIBG VV

WHO Gecoordineerd interlaboratorium onderzoek over de analyse van dioxines and PCB's in moedermelk en bloed

Abstract niet beschikbaarThis report describes the results of a WHO-coordinated interlaboratory comparison study on the analysis of dioxins and PCBs in mother's milk and human blood. The study is biannually organised by the WHO, Regional Office for Europe (Copenhagen) and is aiming at the identification of laboratories capable of the analysis of dioxins and related compounds at a good, internationally accepted standard. In the present study, nineteen laboratories from Europe and North- America have participated for dioxins in mother's milk, sixteen for dioxins in blood and ten and sic for the analysis of PCBs in mother's milk and human blood, respectively. The study consisted of the analysis of three different pools of milk and blood, two of which contained added PCDD/Fs. One of the pools was sent after the results of two previous pools have been reported (test for reproducability). Results were evaluated on the basis of statistical analysis in terms of repeatability, reproducibility and accuracy. In general, coefficients of varation (CV) were better for analysis in mother's milk than for the lower levels in blood. Limits for the qualification of methods were average coefficients of variation of < 20% for analysis of PCBs in milk and blood, <30% for dioxins in milk and <40% for dioxins in blood. All our four methods have been qualified. In the final ranking of laboratories, RIVM-LOC methods scored first positions for PCBs and dioxins in milk and for PCBs in blood and a third position for the analysis of dioxins in blood. The average CVs were 12.4, 3.3, 8.7 and 11,3% for analysis for PCBs and dioxins in milk and blood, respectively.HIMHHIG

Groot vluchtigheidstraject bepaling van polycyclische aromatische koolwaterstoffen (PAK&#65533;s) in de buitenlucht m.b.v. gaschromatografie - isotoopverdunning massa spectrometrie

Een methode is ontwikkeld voor de meting van poly aromatische koolwaterstoffen (PAK) in de buitenlucht m.b.v. gaschromatografie - isotoopverdunning massa spectrometrie. De methode was ontworpen voor de meting van de grootst mogelijke vluchtigheidstraject binnen de groep inclusief de meestvoorkomende en vluchtige naftalenen. Het monstervolume bedroeg circa 500 m3 bij een bemonsteringssnelheid van ca. 18 m3/h. Het monstername apparaat bevatte drie sorptie trappen voor de simultane bemonstering van resp. de deeltjes gebonden fractie, de weinig vluchtige en de vluchtige PAK�s. De recoverie van de methode bedroeg gemiddeld ca. 90 %. De detectiegrens was circa 5 pg/m3 voor de niet-vluchtig en deeltjes gebonden fractie. Resultaten van toepassing van de methode in een woongebied (Bilthoven) toonden een vrij stabiel profiel van voorkomen van de belangrijkste PAK congeneren in achtergrondlucht. Vergelijking van specifieke verhoudingen van bepaalde PAK congeneren met literatuur gegevens duidde op een belangrijke bijdrage van verkeer aan PAK�s in lucht.A method was developed for the measurement for polycyclic aromatic hydrocarbons in ambient air by gas chromatography isotope dilution mass spectrometry. The method was designed to measure the largest possible volatility range of PAHs including the abundant naphthalenes. Samples volumes were approx. 500 m3 in size at a sampling rate of approx. 18 m3/h. The sampler contained three sorption stages for the simultaneous capturing of particle bound and low and high volatile gaseous PAHs, respectively. Recoveries of sampling spikes were on average 90 %. The detection limit was approx. 5 pg/m3 for the high boiling range PAHs. Results obtained showed a quite steady profile for most PAHs in background air in the Netherlands. Comparison of abundance ratios with data in the literature indicate that traffic exhausts were the major source for the PAHs in the area.RIV

[Home-built electrospray ionisation source for a quadrupole mass-spectrometer.]

This report describes the manufacturing, the working and results of preliminary applications of a home-built electrospray ionisation source. The source was constructed for a quadrupole mass-spectrometer (MS) (Finnigan 4000). The elements of the source and interface are: a micro needle at high potential to the capillary, a capillary for transport of the ions and a sampling orifice (skimmer) to the mass analyser and detector. That interface enables the transport of ions from atmospheric pressure to the required high vacuum in the mass analyser as well as an appropriate focussing of ions corresponding. The design concerns the physical dimensions of the different parts and the electrical potentials. The results show that the electrospray process, the transport and the focussing operate satisfactorely. The highest sensitivity was measured for Gramicidin S (polypeptide, MW 1141 Dalton) of about 10 femtomol. For substances with a lower molecular weight the sensitivity was much lower and ranged from about 100 fmol for the polysaccharide streptomycin (MW 581 Da) to 50 pmol for polar low MW herbicides glyfosate and glufosinate. It seems useful to construct an extra focussing device between the skinner and the analyser to enhance the transmission efficiency for the low molecular weight species (<400 Da)

Development of a method for the analysis of polybromo biphenyls and bifenyl oxides in plastics

Dit rapport beschrijft de verdere ontwikkeling van een analysemethode voor de bepaling van brandvertragende middelen polybroombifenylen en -bifenyloxiden (PBB's en PBBO's) in kunststoffen. De methode is bedoeld voor handhavingsdoeleinden van een toekomstige Algemene Maatregel van Bestuur op het verbod tot verwerking van deze stoffen in kunststoffen. Onderzoek betrof met name de isolatie van deze stoffen uit een grote varieteit aan materialen, waarna ze vervolgens m.b.v. gaschromatografie-electronen-invangdetectectie (GC-ECD) zijn bepaald. Onderscheid is gemaakt tussen oplosbare en niet oplosbare kunststoffen. Voor de eerstegenoemde groep is oplossen van het materiaal de meest eenvoudige en betrouwbare methode voor de kwantitatieve isolatie van de PBB's/PBBO's. Voor niet oplosbare kunststoffen is de reflux-extractietechniek (Soxhlet) onderzocht. Kritische parameters hierin zijn de extractieduur en het rendement. De methode is toegepast op een proefmonster van het niet-oplosbare low density polyethyleen (LDPE). De minimale extractieduur bedroeg 2 h bij een opbrengst van minimaal circa 75%. Opgelost polymeer na beide methoden veroorzaakte geen problemen bij de analyse, mede door de zeer sterke verdunning van extracten/oplossingen. Neerslaan van opgelost polymeer kan zonodig worden toegepast. Hierbij traden geen verliezen op. Extracten en oplossingen zijn voor analyse verdund tot een verhouding van 1 deel kunststof per 1.000.000 delen oplosmiddel. De gevoeligheid van de methode was beter dan de vereiste ondergrens van 1 g PBB/PBBO's per kg kunststof (0.1 gew%). De lineariteit van de methode, met name de detectie, bedraagt circa twee orden van grootte, en kan door extra verdunnen van extracten naar gewenst niveau worden uitgebreid. Andere kenmerken als precisie en reproduceerbaarheid waren vanwege het ontbreken van betrouwbare standaarden en referentiematerialen niet nauwkeurig te bepalen. Voor de toepassing van de methode in de praktijk zullen deze nog nader moeten worden vastgesteld middels een interlaboratorium vergelijkings- en validatie-onderzoek. Hiervoor zijn testmaterialen van een grote diversiteit kunststoffen met PBB/PBBO's in het relevante concentratiegebied (0.1-25 gew%) dringend gewenst.This report describes the development of a method for the analysis of polybromo biphenyls and bifenyl oxides (PBBs/PBBOs) in plastics. The method will be used for regulatory purposes on the possible future banning of these compounds. Investigations were mainly focused on the liberation of these compounds from the solid samples. Analysis was performed by the proposed method of choice, gas chromatography-electron capture detection (GC-ECD). For this purpose the materials of interest were divided into solvable and non-solvable materials. For solvable material, analytes were quantitatively liberated from the matrix simply by dissolvation of the material. For non-solvable materials, reflux extraction in toluene using the Soxhlet method was studied and tested on low density polyetylene (LDPE). Critical parameters for this method are the duration of extraction and the corresponding yield. For LDPE the extraction time of 2 h was found suitable, with an estimated yield of 75%. In both methods, dissolved polymer did nor cause interferences or other problems during GC-ECD analysis. Precipitation of dissolved polymers can be applied when required. No losses of analytes were observed during this process. Extracts and solutes were highly diluted prior to analysis, viz. to a ratio of 1 part of material into 1.000.000 parts of solvent (ppb). The limit of determination of the method was better than the required level of 1 g PBB/PBBO/kg (0.1 w%). The linearity of the method was limited by the ECD detector to about two orders of magnitude, but can be increased by a further dilution of final extract in proportion to the expected level in the material under investigation. Other performance characteristics of the proposed method could not be determined due to the lack of reference materials. Before implementing in practice, these should be evaluated preferably in an interlaboratory comparison and validation trial. For this purpose and for future use in the laboratories involved, a larger variety of appropriate reference materials known addition levels should be made available.DGM/SV

[Determination of polychlorodibenzo-p-dioxins and furans in ambient air from a rural area in the North East of the Netherlands.]

Abstract niet beschikbaarThis report describes the results of immission measurements for PCDD/F in a rural area in the North East of the Netherlands (Drenthe). Results of these measurements show that the average background concentration of polychlorodibenzo-p-dioxins (PCDDs) and furans (PCDFs) in ambient air were about 30 +- 15 fg TEQ/m3. This value is higher than the predicted concentration of 10-20 fg TEQ/m3 based on the results of the dispersion and deposition model (OPS-model). In addition, also tetra-and-pent- congenerprofiles and congener patterns are studied and compared with emissions patterns.HIMH HIGB VV

[Determination of polychlorodibenzo-p-dioxins and furans in ambient air from an urban area in the Netherlands (Part IV).]

Abstract niet beschikbaarThis report describes the results of polychlorodibenzo-p-dioxins (PCDDs) and furans (PCDFs) measurements in ambient air in a rural area in the centre of the city conglomerate 'Randstad", about 30 km North of a large industrial area 'Botleck' and two large capacity refuse waste incinerators (Rotterdam and AVR). Measurements were performed near the village of Zegveld during the period of June and July 1993. Dioxin concentrations found varied between 5+-2 to 60+-15 fg TEQ/m3, depending on the wind direction and other weather conditions with an average value of 18+-18 fg TEQ/m3 (n=11). The high range levels were found in trajectories from the South-West, down stream from the incinerators, and relatively low levels (<5-10 fg TEQ/m3) in trajectories from West (North Sea), North and East. The long-term-average background level was calculated as 25+-5 fg TEQ/m3 based on estimates of mean concentrations in the four trajectory directions, weighed with the corresponding long-term-average distribution of wind directions. This background value corresponds fairly well with a predicted value of 35 fg/m3. Model calculations were based on the estimated national emissions and dioxin fluxes from abroad by the end of 1990. When results from both methods are mutually comparable and valid, the small difference might indicate a small, poorly significant dicline of dioxin levels in air in this part of the country during the past few years.HIMH HIGB VV

[Determination of polychlorodibenzo-p-dioxins and furans in ambient air from an urban area in the Netherlands (part III).]

Abstract niet beschikbaarThis report describes the results of immission measurements for PCDD/F in an urban area in the South East of the Netherlands (Zuid-Limburg). Results of these measurements show that the average background concentration of polychlorodibenzo-p-dioxins (PCDDs) and furans (PCDFs) in ambient air were about 54 +- 19 fg TEQ/m3. This value is higher than the predicted concentration of 20-30 fg TEQ/m3 based on the results of the dispersion and deposition model (OPS-model).HIMH HIGB VV