T.J. Nestrick

Determination of trace phenols in water by gas chromatographic analysis of heptafluorobutyryl derivatives

Abstract An analytical procedure is described that permits the determination of phenol and substituted phenols, which do not possess inherent electron-capture sensitivity, at concentrations ⩾10 ng/ml in aqueous media by gas chromatographic analysis of the heptafluorobutyryl derivatives. Sample pre-concentration is not required, and a single benzene extraction removes phenolics from the water matrix prior to derivatization. The gas chromatographic analysis is performed on a column packing which exhibits high efficiency and low column bleed. These characteristics allow the determination of a large number of components in a single temperature-programmed electron-capture gas chromatographic analysis in less than 15 min. Recoveries of ten phenolics at the 20–200 ppb level are ca. 75% or greater.

Presence of chlorodibenzo dioxins in a sealed 1933 sample of dried municipal sewage sludge

Abstract Analysis of a sample of MILORGANITE® fertilizer which had been sealed in glass for exhibition in 1933 shows a broad range of chlorodibenzo-p-dioxins remarkably similar to that of more recent material. It is speculated that the compounds were formed mainly by condensation reactions after chlorination of phenolic substances in the water supply and wastes.

Novel extraction device for the determination of chlorinated dibenzo-p-dioxins (CDDs) and dibenzofurans (CDFs) in matrices containing water

Abstract The efficient extraction of CDDs/CDFs from particulate matrices containing measurable amounts of water is complicated by the need to remove the water from the particles before beginning the extraction process. Traditionally, this has been done by pre-extracting the sample with a water miscible solvent such as isopropanol or by air drying for an extended period of time over various desiccants such as sulfuric acid or phosphorus pentoxide. These techniques can suffer from three possible problems: potential loss of analytes, accidental sample contamination, or an unacceptably long sample drying time. In response to these drawbacks, we have developed an extraction device that combines the simultaneous removal and measurement of water from a particulate sample with an exhaustive Soxhlet extraction of the dried particulates.

Thermolytic surface-reaction of benzene and iron (III) chloride to form chlorinated dibenzo-p-dioxins and dibenzofurans

The investigation of a potential “denovo” synthesis for chlorinated dibenzo-p-dioxins and dibenzofurans (CDDs/CDFs) from simple compounds that can be formed during the combustion of natural fuels is presented. The interaction of benzene in the gas phase with FeCl3 on a supporting-surface is demonstrated to produce trace quantities of CDDs/CDFs over a wide range of precursor composition and thermolytic conditions. Molar yields of 0.00004% for CDDs and 0.013% for CDFs are typical for this reaction under laboratory conditions. Additional species produced in significantly greater yield include: chlorobenzenes, chlorobiphenyls and chlorodiphenyl ethers Benzene is demonstrated to be a definitive precursor for CDD/CDF products via use of [13C6]-benzene.

Perspectives of a large scale environmental survey for chlorinated dioxins: overview and soil data

Abstract On November 5, 1984, The Dow Chemical Company issued a report entitled: “Point Sources and Environmental Levels of 2378-TCDD on the Midland Plant Site of The Dow Chemical Company and in the City of Midland, Michigan.” This report is based upon the efforts of a 22-person task force who dedicated approx. 21 months of effort to the generation and analysis of over 6000 analytical data points regarding specific CDD/CDF concentrations in the four basic environmental elements of air, earth, fire (incineration), and water. A summarization of this study will be presented which includes methodology, analytical QA-QC criteria, and representative soil analyses, as they pertain to the survey conclusions.

Interlaboratory testing study on 2,3,7,8-substituted polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran isomer standard solutions

Abstract Carefully prepared isomer standard solutions of all 17 of the 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans and their corresponding crystalline materials were provided to nine environmental analytical laboratories for the purpose of performing a round robin study of the accuracy and reliability of the standard solutions. Consensus values were determined for each isomer. Good correlation was found between the target values and the consensus values.

Analytical methodology of the Dow Chemical Company for the determination of selected chlorinated dibenzo-p-dioxins and dibenzofurans in stack gas effluent matrices: Part I: Full method for determination of tetra- through octa-chlorinated congener group total concentrations and “2378”-substituted isomers

Abstract This procedure permits the determination of CDDs/CDFs (chlorinated dibenzo-p-dioxins and dibenzofurans), over the range of congener groups having from four to eight chlorine substituents, in stack gas effluent samples containing both gaseous and particulate emissions. Stack gas samples are collected isokinetically from an operating process vent to the atmosphere using a United States Environmental Protection Agency (US EPA) modified Method 5 sample collection train. Analytes are recovered by subjecting the entire contents of a sampling train to extraction with benzene so as to produce a total-sample-crude-extract. An aliquot of the crude extract is fortified with [ 13 C 12 ]-labeled CDD/CDF isomer internal standards and subjected to a classical liquid-column chromatographic cleanup procedure that is designed to isolate a crude CDDs/CDFs fraction which contains all isomers having ≥4 chlorine substituents. Total congener group concentrations are determined by examination of this fraction via HRGC-LRMS (high resolution gas chromatographylow resolution mass spectrometry) techniques. When specific isomer determinations are required within congener groups bearing from 4 to 6-chlorine atoms, it is necessary to subject the remainder of the crude CDDS/CDFs fraction to further cleanup via a 2-dimensional HPLC (high performance liquid chromatography) technique which permits isolation of the desired analytes on the basis of compound specific retention indices. Final HRGC-LRMS examination of these fractions provides the necessary qualitative and quantitative data for each analyte.

Derivatization procedure for the determination of chloroacetyl chloride in air by electron capture gas chromatography

Abstract A gas chromatographic method is described for the determination of chloroacetyl chloride (CAC) in air in the presence of monochloroacetic acid (MCA). Air containing CAC was bubbled through a reactant solution of 2,4,6-trichlorophenol (TCP) and pyridine in toluene to produce the derivative 2,4,6-trichlorophenyl chloroacetate (TCPC). Excess TCP was removed by extractions with 1 N sodium hydroxide, and TCPC was determined via electron capture gas chromatography. An average recovery of 76 ± 4% (mean ±S.D.) was obtained when CAC was added directly to the reactant solution. When air samples containing CAC were scrubbed and analyzed, recoveries averaged 70 ± 5% (mean ±S.D.). The quantitative detection limit (2.5 × noise) was 1 ng CAC/ml in the extracted organic layer [1 ppb 1 in air for a 5-1 sample]. The general applicability of this method for volatile acid halides was also explored.

Perspectives of a large scale environmental survey for chlorinated dioiins: water analyses

Abstract During 1983 and 1984, The Dow Chemical Company conducted a study to determine the extent of dioxin contamination at its Midland, Michigan plant and the surrounding area. The primary objectives of this study were to identify, rank order, and when possible quantify potential sources of dioxins to the environment and also to determine the extent of contamination in areas affected by the Dow facility. Early in the study, it was estimated that approximately 0.6g/year of 2378-TCDD was being emitted in 2.5 × 10 10 L of wastewater effluent. Data will describe observed sources of TCDD (both current and historical), environmental levels, existing water treatment methods, control measures taken, and future improvements on the water system to reduce TCDD in the effluent.

Purge vessel design in determinations of volatile organic compounds

Abstract Five purge vessels are described for use in determinations of volatile organics. Less conventional designs permit extension of the technique to untraditional samples, including soil and viscous glues.