EPA-600/4-81-062 July 1981 DETERMINATION OF HALOETHERS IN INDUSTRIAL AND MUNICIPAL WASTEWATERS by Paul L. Sherman, Joseph M. Kyne, Roger C. Gable, John V. Pustinger, and Carl R. McMillin Monsanto Research Corporation Dayton, Ohio 45407 Contract No. 68-03-2633 Project Officer James Longbottom Physical and Chemical Methods Branch Environmental Monitoring and Support Laboratory Cincinnati, Ohio 45268 U.S. Environmental Protection Agency Region V, Libr?ry 2 JO South Dearborn Street Chicago, Illinois 60604 ENVIRONMENTAL MONITORING AND SUPPORT LABORATORY OFFICE OF RESEARCH AND DEVELOPMENT U.S. ENVIRONMENTAL PROTECTION AGENCY CINCINNATI, OHIO 45268 NATIONAL TECHNICAL INFORMATION SERVICE ------- DISCLAIMER This report has been reviewed by the Environmental Monitoring and Support Laboratory, U.S. Environmental Protection Agency/ and approved for publication. Approval does not signify that the contents necessarily reflect the views and policies of the U.S. Environmental Protection Agency, nor does mention of trade names or commercial products constitute endorsement or recom- mendation for use. 11 ------- FOREWORD Environmental measurements are required to determine the quality of ambient waters and the character of waste effluents. The Environmental Monitoring and Support Laboratory-Cincinnati con- ducts research to: • Develop and evaluate techniques to measure the presence and concentration of physical, chemical, and radiological pollutants in water, wastewater, bottom sediments, and solid waste. • Investigate methods for the concentration, recovery, and identification of viruses, bacteria, and other microbio- logical organisms in water. Conduct studies to determine the responses of aquatic organisms to water quality. • Conduct an Agency-wide quality assurance program to assure standardization and quality control of systems for monitor- ing water and wastewater. Under provisions of the Clean Water Act, the Environmental Pro- tection Agency is required to promulgate guidelines establishing test procedures for the analysis of pollutants. The Clean Water Act Amendments of 1977 emphasize the control of toxic pollutants and declare the 65 "priority" pollutants and classes of pollut- ants to be toxic under Section 307(a) of the Act. This report is one of a series that investigate the analytical behavior of selected priority pollutants and suggests a suitable test pro- cedure for their measurement. Dwight G. Ballinger Director Environmental Monitoring and Support Laboratory 111 ------- ABSTRACT This document describes an analytical method, not based on mass spectrometry, for the analysis of haloethers in water and wastewater. The following haloethers were originally included in this study: 2-chloroethyl vinyl ether, bis(2-chloroisopropyl) ether, bis (2- chloroethyl) ether, bis(2-chloroethoxy) methane, 4-chlorophenyl phenyl ether, 4-bromophenyl phenyl ether, and (bischloromethyl) ether. The 2-chloroethyl vinyl ether and the bis(chloromethyl) ether were later deleted from the project because of extreme volatility and hydrolytic instability, respectively. A literature search was conducted to acquire published informa- tion on the hydrolytic stability of the haloehters, methods for the detection of haloethers in water, and methods for the isolation, concentration, and analysis of haloethers. Gas chromatography studies were completed to compare different pack- ings for use with haloethers and to compare the results obtained using a Hall electrolytic conductivity detection with those obtained using an electron capture detector. Various solvents were evaluated for use in extracting haloethers from wastewater. Sample preservation was studied at various pH and residual chlo- rine levels and different temperatures. The stability of halo- ethers stored in acetone and in methanol was observed. Chroma- tographic cleanup procedures were investigated for the removal of potential interferences. The workable method developed in this program for the analysis of haloethers in wastewater consisted of a liquid/liquid extraction using methylene chloride, an evaporation step using Kuderna- Danish (K-D) evaporators, a column chromatographic cleanup pro- cedure using Florisil, another K-D evaporation of the fraction from the Florisil column, and subsequent analysis by gas chro- matography using an electrolytic conductivity detector. This report was submitted in partial fulfillment of Contract No. 68-03-2033 by Monsanto Research Corporation under the sponsor- ship of the U.S. Environmental Protection Agency. This report covers the period 25 October 1977 through 31 December 1978. IV ------- CONTENTS Foreword ill Abstract iv Figures vi Tables vii 1. Introduction 1 2. Summary 2 3. Haloethers literature review 4 Introduction 4 Hydrolytic stability ..... 5 Detection of haloethers in water 10 Methods for the isolation, concentration, and analysis of haloethers 11 4. Gas Chromatography Studies 18 Columns and conditions 18 Initial detector studies 23 5. Extraction Studies 29 Extraction at pH 2 29 Extraction at pH 7 30 Extraction at pH 10 30 6. Preservation Studies 34 Preparation 34 Results 34 7. Solvent Stability Studies 37 8. Resin Studies 44 9. Column Chromatography Studies 47 Column packed with Florisil 47 Column packed with silica gel 48 10. Application of Method to Wastewater Samples. ... 53 References 59 Appendices A. Method for Sampling and Analysis 63 B. Standardization of Florisil 69 v ------- FIGURES Number Page 1 Chromatogram of haloethers on column packed with SP-1000 on Supelcoport and using flame ioniza- tion detector 20 2 Chromatogram of haloethers on column packed with SP-100 on Supelcoport and using Hall electrolytic conductivity detector 20 3 Chromatogram of haloethers on column packed with Tenax-GC and using flame ionization detector ... 21 4 Chromatogram of haloethers on column packed with Tenax-GC and using Hall electrolyte conductivity detector 21 5 Chromatogram of haloethers with new conditions ... 23 6 Calibration curve for CPPE 24 7 Chromatogram of BCIPE on column packed with SP-1000 and detected simultaneously using FID and electron capture detectors, showing electron-capture impurities 25 8 Chromatogram of haloethers on column packed with SP-1000 and detected using an electron capture detector 25 9 Chromatogram of haloethers on the modified Hall Model 700 detector 27 10 Chromatogram showing the response of BCME in comparison to three other haloethers on column packed with SP-1000 on Supelcoport 28 11 Typical Chromatogram for CEVE with purge and trap system 33 VI ------- TABLES Number 1 Haloethers in this Study 4 2 Amount of BCME Formed at 40% Relative Humidity and 26°C at Various CH20/HC1 Concentrations in Air. . 7 3 Amount of BCME Formed at Various Relative Humidities and Room Temperature at Various CH20/HC1 Concen- trations in Air 8 4 Hydrolysis Half-Life of BCME in Humid Air 8 5 Hydrolysis of Bis(chloromethy) Ether in Water and Aqueous HCl and NaOH 10 6 Haloethers Detected in Water 12 7 Analysis of Haloethers in Air with Porous Polymer Absorber/Gas Chromatography/Mass Spectrometry . . 14 8 Derivative Formation for Analysis of BCME in Air. . 16 9 Analysis of Haloethers in Water 17 10 Haloether Chromatographic Conditions for Columns Packed with SP-1000 or Tenax-GC 19 11 Retention Times of Haloethers on Two GC Columns Relative to Aldrin 19 12 New Haloether Chromatographic Conditions for Column Packed with SP-1000 22 13 Haloether Chromatographic Conditions for Column Packed with SP-1000 and Using Electron Capture Detector 24 14 Sensitivity for Haloethers 26 15 Reproducibility Data 27 16 Results of Extraction Studies 31 17 Results of Anova for Solvent Extraction Studies . . 31 18 Conditions for GC/MS Analysis of CEVE 32 19 Percent Recovery for CEVE 32 20 Preservation Study Results 35 21 Results of Anova Analysis of Preservation Study Results 36 22 Average Recovery (%) of Haloethers from Preservation Study Samples at Neutral and Basic pH 36 23 Concentrations of Solvent Solutions 37 24 Concentrations of Standards 38 25 Haloether Chromatographic Conditions with Electron Capture Detector 38 26 Concentration of Initial Methanol Solution Used for Solvent Stability Study 38 VII ------- TABLES (continued) Number Page 27 Concentration of Initial Acetone Solution Used for Solvent Stability Study 39 28 Results of Analysis of Methanol Solution After Storage for 30 Days 39 29 Results of Analysis of Acetone Solution After Storage for 30 Days 40 30 Results of Analysis of Methanol Solution After Storage for 60 Days 40 31 Results of Analysis of Acetone Solution After Storage for 60 Days 41 32 Results of Analysis of Methanol Solution After Storage for 90 Days 41 33 Results of Analysis for Acetone Solution After Storage for 90 Days 42 34 Comparison of All Storage Times. . 42 35 Statistical Data for XAD-2 Resin at pH 2 44 36 Statistical Data for XAD-2 Resin at pH 7 45 37 Statistical Data for XAD-2 at pH 10 45 38 Average Recovery Percent (Three Detectors) of Haloethers on Chromatographic Column Packed with Florisil and Eluted with 200 mL 6% Ethyl Ether in Petroleum Ether 47 39 Recovery of Haloethers on Chromatographic Column Packed with Silica Gel and Eluted with Methylene Chloride in Hexane - First FID Analysis 49 40 Recovery of Haloethers on Chromatographic Column Packed with Silica Gel and Eluted with Methylene Chloride in Hexane - Second FID Analysis 50 41 Recovery of Haloethers on Chromatographic Column Packed with Silica Gel and Eluted with Methylene Chloride in Hexane - Third FID Analysis. ..... 51 42 Recovery of Haloethers on Chromatographic Column Packed with Silica Gel and Eluted with Methylene Chloride in Hexane - (Hall Model 700) 52 43 Distribution of Wastewater Sample Portions 53 44 Concentration of Haloethers in Spiking Solution. . . 53 45 Recovery of Haloethers from Wastewater from Municipal Secondary Waste Treatment Plant Using Column Packed with SP-1000 and Hall Electrolytic Conductivity Detector 54 46 Average Results for Five Analyses of Haloether Standard Analyzed on Column Packed with SP-1000 and Using Hall Electrolytic Conductivity Detector. 55 47 Percent Recoveries of Haloethers from Industrial and Municipal Wastewater (Determined by Peak Amplitude) Using Column Packed with SP-1000 and Hall Electro- lytic Detector (Average of Three Samples) 56 48 "t" Values for Three Sets of Wastewater Samples. . . 57 viii ------- SECTION 1 INTRODUCTION This report describes work completed on EPA contract 68-03-2633, "Development and Application of Test Procedures for Specific Toxic Substances in Wastewater, Category 2: Haloethers." The objective of this program is to develop a method for the analysis of haloehters in water and wastewater which does not involve mass spectrometry. The following haloethers were included in this study: 2-chloro- ethyl vinyl ether (CEVE), bis(2-chloroisopropyl) ether (BCIPE), bi(2-chloroethyl) ether (BCEE), bis(2-chloroethoxy) methane (BCEXM), 4-chlorophenyl phenyl ether (CPPE), and 4-bromophenyl phenyl ether (BPPE). Bis(chloromethyl) ether (BCME) was origi- nally included in this category; however, due to its hydrolytic instability, BCME was removed from this study, but its chroma- tographic retention time was determined under the same conditions as the other six haloethers. The following studies were included in this project: a litera- ture review, gas chromatography, solvent stability, sample extraction and preservation, column chromatography, resin per- formance, and the application of the analytical technique to actual wastewater samples. Accomplishments are summarized in Section 2. Detailed description of all studies are provided in Sections 3 through 10 of this report. ------- SECTION 2 SUMMARY The objective of this study is to develop a method for the analysis of haloethers in water and wastewater that does not in- volve mass spectrometry (GC/MS). The method developed involves sample extraction, cleanup, and analysis by gas chromatography with an electrolytic conductivity detector. This category originally included seven compounds: chloroethyl vinyl ether (CEVE), bis (2-chloroisopropyl) ether (BCIPE), bis(2-chloroethyl) ether (BCEE), bis(2-chloroethoxy) methane (BCEXM), bis(chloro- methyl) ether (BCME), 4-chlorophenyl phenyl ether (CPPE), and 4-bromophenyl phenyl ether (BPPE). BCME and CEVE were subse- quently removed from the list, the former because of its hydro- lytic instability in water, and the latter because of its extreme volatility. Two gas chromatographic packings were compared for best results with these haloethers. The 3% SP-1000 on Supelcoport was found to be superior to Tenax-GC because of better peak shape and resolution. Comparison of the Hall electrolytic conductivity detector with the electron capture detector showed the Hall detector to be the better choice because of its specificity. The Hall detector also has better reproducibility and lower detection limits for the haloethers. Studies were completed to determine the best methods for sample- extraction and preservation, including resin sampling. A solvent stability study was also conducted. The following solvents were evaluated for the extraction of haloethers from wastewater: methylene chloride, 15% ethyl ether in hexane, and pentane. For this liquid/liquid extraction, methylene chloride proved to be the best extracting solvent. The possible use of Ambersorb XE-340 and XAD-2 resins for sample collection was also studied. Very little difference was found between the liquid/liquid extraction and the resin sorption methods. The average percent recovery for the four haloethers (BCIPE, BCEE, BCEXM, and BPPE) was 67% using resin sorption and 68.3% using liquid/liquid extraction. While there seemed to be little difference between the direct sampling parameters (pH, temperature, and residual chlorine), the XAD-2 was definitely the better choice of sampling resin because the haloethers could not be stripped from the Ambersorb XE-340 resin. ------- Sample preservation was determined at three different pH levels (2, 7, and 10) and with residual chlorine levels of 0 ppm and 2 ppm using temperatures of 0°C and 25°C. A study was also com- pleted to compare the storage stability of the haloethers in acetone and methanol. Samples of the haloethers in these water miscible solvents were stored in flame-sealed glass ampules under normal laboratory conditions for periods of 30, 60, and 90 days. CEVE was found to be very unstable in methanol, but the other five haloethers were very stable in both solvents. Two chromatographic cleanup procedures involving silica gel and Florisil were investigated for the removal of potential inter- ferences in actual wastewater samples. Column chromatography on silica gel yielded very erratic and irreproducible results, but the Florisil cleanup procedure produced very stable and accept- able results. A study was performed to determine the validity of the analytical method developed for application to actual wastewaters. Four samples were obtained, one from a municipal source and three from industrial sources. The samples were spiked, extracted, evap- orated, column chromatographed, and evaporated again before analysis by gas chromatography with an electrolytic conductivity detector. One of the industrial effluent extracts was too com- plex for analysis using extraction and column chromatographic methods developed during this project. A "t" test was performed on the data from these four sets of samples. The only signifi- cant difference in recovery occurred between samples extracted and those processed by resin sorption; resin sorption yielded better recovery for the two industrial samples. All of the aforementioned studies led to the development of an actual workable method for the analysis of wastewater. This method involved a liquid/liquid extraction using methylene chlo- ride, an evaporation step using Kuderna-Danish (K-D) evaporators, a column chromatographic cleanup procedure using Florisil, another K-D evaporation of the fraction from the Florisil column, and subsequent analysis by gas chromatography using an electro- lytic conductivity detector. ------- SECTION 3 HALOETHERS LITERATURE REVIEW INTRODUCTION A review of literature pertinent to the seven haloethers included in this program was conducted during November 1977, prior to the preliminary contract meeting. The seven haloethers of interest and their abbreviations are listed in Table 1. Information in this report was gathered from a literature search performed by MRC in 1976 on EPA contract 68-01-1980, a literature review of haloethers conducted by Syracuse University in 1975 (1), and a computerized literature search of three commercial search ser- vices, the National Library of Medicine, System Development Cor- poration, and Lockheed Information Systems. These information sources provided coverage of all scientific literature in this report through approximately 15 November 1977. The main topics discussed in the following sections are hydrolytic stability of haloethers, reports of detection of haloethers in water, and methods for the isolation, concentration and analysis of haloethers. TABLE 1. HALOETHERS IN THIS STUDY Compound Abbreviation' Bis(chloromethyl) ether BCME 2-Chloroethyl vinyl ether CEVE Bis(2-chloroethyl) ether BCEE Bis (2-chloroisopropyl) ether BCIPE Bis (2-chloroethoxy) methane BCEXM 4-Chlorophenyl phenyl ether CPPE 4-Bromophenyl phenyl ether BPPE (1) Durkin, P. R., P. H. Howard, and J. Saxena. Investigation of Selected Potential Environmental Contaminants: Halo- ethers. EPA 560/2-75-006, U.S. Environmental Protection Agency, Washington, D.C., September 1975. 178 pp. ------- HYDROLYTIC STABILITY Literature related to the hydrolytic stability of chloroethers can be divided into two types: 1) information related to all of the ethers except BCME, and 2) data related to BCME. These types are discussed separately below. Haloethers Other Than BCME Bohme and Sell (2) measured the hydrolysis rate of BCEE in a dioxane-water mixture (20M water in dioxane) at 100°C.- The half- life for BCEE under these conditions was 12.8 days. Van Duuren and co-workers (3) measured the kinetics of the hydrolysis of microliter quantities of six chloroethers in 10 mL of a water- formaldehyde (3:1) solution. The hydrochloric acid formed was titrated with an automatic recording titrator. The half-life of all ethers with alpha-chloro substituents was found to be less than 2 minutes, and the half-life of ethers with no alpha-chloro substitution was greater than 23 hours. The half-life of BCME was listed in this study as less than 2 minutes and that of BCEE as greater than 23 hours. Salomaa and associates (4) have stud- ied the hydrolysis of chlorovinyl eithers and chloro-substituted acetals under acid conditions . They found that chlorovinyl ethers, such as chloroethyl vinyl ether, are readily hydrolyzed to an aldehyde and alcohol as shown in Equation 1. C1CH2CH2-0-CH=CH2 3 • C1CH2CH2OH + CH3-C-H (1) Their equations for two hydrolysis pathways for chloro- substituted acetals are shown below: H+ + C1CH2CH2OCH2 OCH2CH3 — - — »-ClCH2CH2O=CH2 + HOCH2CH3 (2) H+ C1CH2CH2 OCH2OCH2CH3 — -— +• C1CH2CH2OH + CH2=OCK2CH3 (3) (2) Bohme, H. and K. Sell. The Hydrolysis of Halogenated Ethers and Thio Ethers in Water-Dioxane Mixtures. Chem. Ber., 81:123-130, 1973. (3) Van Duuren, B. L., C. Katz, B. M. Goldschmidt, K. Frenkel, and A. Sivak. Carcinogenicity of Halo-ethers. II. Struc- ture - Activity Relation of Analogs of Bis(chloromethyl) ether. J. Nat. Cancer Inst., 48:1431-1439, 1972. (4) Salomaa, P., A. Kankaanpera, and M. Lajuneh. Protolytic Cleavage of Vinyl Ethers. General Acid Catalysis, Struc- tural Effects and Deuterium Solvent Isotope Effects. Acta. Chem. Scand., 20 (7):1790-1801, 1966. ------- As part of a hazard priority ranking program for the National Science Foundation, Stanford Research Institute (5) predicted a half-life of 38.2 days for BCEE in water at a pH of 7. One other process for the catalytic cleavage of BCIPE, based on a patent by Dow Chemical Company, is shown below (6): HCl (C1CH2CH[CH3])20 7 ~T ** CH3-CH-CH2C1 and CH3-CH-CH2C1 (4) 6m,J.2 I | Cl OH Bis(chloromethyl) Ether The hydrolysis of BCME has been studied very extensively during the past ten years. Because BCME had been found to be a very potent carcinogen, the hydrolysis mechanism has been studied as a possible pathway for the destruction of the compound. Van Duuren, et al, (7, 8) reported that BCME reaches an equilibrium with its hydrolysis products, formaldehyde (CH20) and hydrogen chloride (HCl), in aqueous solutions as shown in Equation 5. H20 0 C1CH2OCH2C1-* HCH + HCl (5) Where this hydrolysis was studied in heavy water (D2O) (7), approximately 70% of the BCME was hydrolyzed in 2 minutes, and 80% after 18 hours according to the Van Duuren study. A number of other subsequent studies have explored the formation of BCME from HCl and formaldehyde in air or water and the hydrolysis of BCME in moist air or water. The status of hydrolysis studies in air are discussed below, followed by a discussion of hydrolysis studies in aqueous environments. (5) Brown, S. L., F. Y. Chan, J. L. Jones, D. H. Liu, K. E. McCaleb, T. Mill, K. N. Sapios, and D. E. Schendal. Research Program on Hazard Priority Ranking of Manufactured Chemicals (Chemicals 61-79). NSF-RA-E-75-190D, National Science Foundation, Washington, D.C., April 1975. 198 pp. (6) Roberts, R. F., Jr. Catalytically Cleaving Dichloro- isopropyl Ether. U.S. Patent 3,723,544 (to Dow Chemical Co.), 27 March 1973. (7) Van Duuren, B. L., A. Sivak, B. M. Goldschmidt, C. Katz, and S. Melchionne. Carcinogenicity of Halo-ethers. J. Nat. Cancer Inst., 43:481, 1969. (8) Van Duuren, B. L. Carcinogenic Epoxides, Lactones and Halo-ethers and Their Mode of Action. Ann. New YOrk Acad. Sci. 163:633-651, 1969. ------- The results of Van Duuren, et al, essentially went unnoticed with regard to their potential for the formation of BCME from HCl and formaldehyde or their potential for the incomplete hydrolysis of BCME (as indicated by only 80% hydrolysis after 18 hours). In 1973, Rohm and Haas Company (9) preliminarily announced that part-per-billion (ppb) levels of BCME may be formed in humid air from low levels of HCl and formaldehyde (5 ppm and 2 ppm, respec- tively) . Subsequent studies by Frankel, et al., of Rohm and Haas (10) and by Kallos and Solomon of Dow Chemical Company (11) found that the potential was not as great as had been initially be- lieved. Results of the Frankel Study are shown in Table 2. TABLE 2. AMOUNT OF BCME FORMED AT 40% RELATIVE HUMIDITY AND 26°C AT VARIOUS CH2O/HC1 CONCENTRATIONS IN AIR (10) CH20/HC1, ppm/ppm BCME, ppb 4,000/40,000 5,000 1,000/10,000 730 1,000/1,000 130 300/300 23 100/100 3 20/20 <0.5 (limit of detection) In the Kallos and Solomon study, BCME was found to be formed in five of 18 sample mixtures of HCl and CH20 as shown in Table 3. The reactant concentrations in both studies in which detectable BCME was formed were greater than can be tolerated by humans. One reason for the concern about the formulation of BCME from CH2O and HCl in air is the relatively long half-life of BCME in (9) Bis(chloromethyl) Ether Can Form Spontaneously. Chem. Eng, News, 51(2) :13, 8 January 1973. (10) Frankel, L. S., K. S. McCallum, and L. Collier. Formation of Bis(chloromethyl) Ether from Formaldehyde and Hydrogen Chloride. Environ. Sci. Technol., 8(4):356-359, 1974. (11) Kallow, G. J. and R. A. Solomon. Formation of Bis(chloro- methyl) Ether in Simulated Hydrogen Chloride-Formaldehyde Atmospheric Environments. Amer. Ind. Hyg. Assoc. J., 34:469-473, November 1973. ------- TABLE 3. AMOUNT OF BCME FORMED AT VARIOUS RELATIVE HUMIDITIES AND ROOM TEMPERATURE AT VARIOUS CH2O/HC1 CONCENTRATIONS IN AIR (11) CH20/HC1 , ppm/ppm 3,000/10,000 750/10,000 1,000/500 500/1,000 500/1,000 BCME, ppb 48 2 0.6 0.3 0.3 humid air. The results of Tou (12) show the half-life of BCME to be as long as 25 hours in air. The results of their study of the hydrolysis of BCME in air in various reaction vessels are shown in Table 4. These results for the formation and hydrolysis of BCME in air have been included in this report because any BCME formed in air can enter the aquatic system through washout or absorption. TABLE 4. HYDROLYSIS HALF-LIFE OF BCME IN HUMID AIR (12) ReactorRelativeHalf-life, material T, °C humidity, % hr Glass 25 67 20 Fused ground glass 25 81 25 Fe203-powder 23 42 9.0 Coated saran 23 81 7.2 (12) Tou, J. C. and G. J. Kallos. Kinetic Study of the Stabili- ties of Chloromethyl Methyl Ether and Bis(chloromethyl) Ether in Humid Air. Anal. Chem., 46(12):1866-1869, 1974. ------- In aqueous systems typically, BCME is rapidly hydrolyzed as reported by Tou and associates (13-15). However, there is potential for the formation of BCME in fairly significant con- centrations in acidic formalin solutions in contact with mate- rial containing chloride ions. The potential for the formation of BCME in such formalin solutions is discussed below followed by a review of the hydrolytio rates of BCME in more normal aqueous solutions. Frankel, et al., (10) have monitored the vapors above formalin slurries of Friedel-Crafts chloride salts and detected BCME in concentrations from 210 ppb with FeCl3 to 1,500 ppb with AlCla. Marceleno, et al., (16) also found BCME in solutions containing MgCl2 catalysts. BCME was found to form in the chloromethylating medium (HCl-CH20-ZnCla) (17). These results indicate that fairly significant amounts of BCME could be present in any formalin solution which contains chloride ion. This result would present a problem in wastewater samples if high concentrations of for- malin solution and chloride ion were present. Recent publications by Tou and associates provide details of studies of the hydrolysis of BCME in aqueous media. In one study, hydrolysis rates were measured for a 1-ppm concentration of BCME in acidic, basic, and neutral aqueous solutions. Results (13) Tou, J. C., L. B. Westover, and L. F. Sonnabend. Kinetic Study of Bis(chloromethyl) Ether Hydrolysis by Mass Spec- trometry. J. Phys. Chem., 78(11):1096-1098, 1974. (14) Tou, J. C. and G. J. Kallow. Study of Aqueous HC1 and Formaldehyde Mixtures for Formation of Bis(chloromethyl) Ether. Amer. Ind. Hyg. Assoc. J., 35:419-422, July 1974. (15) Tou, J. C., L. B. Westover, and L. F. Sonnabend. Analysis of a Non-Crosslinked, Water Soluble Anion Exhange REsin for the Possible Presence of Parts Per Billion Level of Bis(chloromethyl) Ether. Amer. Ind. Hyg. Assoc. J., 36:374-378, May 1975. (16) Marceleno, T. and P. J. Bierbaum. A Preliminary Report on the Formation and Detection of Bis-Chloromethyl Ether in the Industrial and Medical Environment. Presented at American Industrial Hygiene Association Conference, Miami, Florida, 12-17 May 1974. (17) Alvarez, M. and R. T. Rosen. Formation and Decomposition of Bis(chloromethyl) Ether in Aqueous Media. Int. J. Environ. Anal. Chem., 4:241-246, 1976. ------- of this study, presented in Table 5 (13), indicate that under the conditions listed BCME will not survive long enough to per- mit analysis using the techniques to be studied in this program. TABLE 5. HYDROLYSIS OP BIS(CHLOROMETHYL) ETHER IN WATER AND AQUEOUS HC1 AND NaOH (13) Half-life, s Solution 2N NaOH IN NaOH H2O IN HC1 2N HC1 At 0°C 88 108 277 365 630 At 20°C 29 22 38 38 63 At 40°C 11 5 7 6 8 A second study by Tou and associates showed that the hydrolysis rate of BCME is 14 seconds when equal concentrations of hydro- chloric acid and formaldehyde (at 1, 10, 100, 250, and 1,000 ppm) are added to water (14). A third study by the same workers investigated whether the hydrolysis rate of BCME in water would be changed by the presence of a final product (a non-crosslinked, water-soluble, anion exchange resin) produced from BCME (15). Results of the study showed that no BCME existed in the product. In a spiked mixture of BCME with the resin and water, BCME was still hydrolyzed very rapidly. From these studies, it is apparent that the only possible way for BCME to remain in waste- water solution is in a very rapidly agitated water solution con- taining a non-water-soluble organic phase in which BCME has a favorable distribution coefficient compared to water. Even in this situation, BCME would be continually partitioning back into the aqueous phase due to the hydrolysis of the BCME fraction in the aqueous phase. DETECTION OF HALOETHERS IN WATER Since Rosen, et al., (18) discovered the presence of bis(2-chloro- ethyl) ether in the Kanawaha River in West Virginia in 1964, a number of other government workers have reported the detection of haloethers in industrial wastewater, river water, and drinking (18) Rosen, A. A., R. T. Skeel, and M. B. Ettinger. Relation- ship of River Water Odor to Specific Organic Contaminants. J. Water Pollut. Contr. Fedr., 35 (6) :777-782, 1963. 10 ------- water. Table 6 summarizes the compounds found, concentration if determined, and location; references are also provided (18-25). METHODS FOR THE ISOLATION, CONCENTRATION, AND ANALYSIS OF HALOETHERS The isolation, concentration, and analysis methods described in the literature have been directed primarily toward four of the haloethers (BCME, BCEE, BCIPE, and BCEXM) of interest in this program. The reported methods are described separately below for haloethers in air and in water. The air methods are included primarily to describe the gas chromatographic columns which have been utilized to date for the haloethers. Haloethers in Air The primary focus of methods for haloethers in air has been directed toward collection and analysis of BCME; few other references cover methods for other haloethers in air. Three main types of methods have been employed for collection and con- centration of haloethers: direct analysis, absorbers, and deri- vatives. These three methods are discussed in the subsequent (19) Frilous, J. Petrochemical Wastes as a Pollution Problem in the Lower Mississippi River. Paper submitted to Senate Subcommittee on Air and Water Pollution, 5 April 1971. (20) Industrial Pollution of the Lower Mississippi River in Louisiana. PB 229 814, U.S. Environmental Protection Agency, Region VI, Dallas, Texas. April 1972. 154 pp. (21) Kleopfer, R. D, and B. J. Fairless. Characterization of Organic Components in a Municipal Water Supply. Environ. Sci. Technol., 6(12):1036-1037, 1972. (22) Analytical Report New Orleans Area Water Supply Study. EPA 909/9-75-003, 1975. 90 pp. U.S. Environmental Protec- tion Agency, Region VI, Dallas, Texas. (23) Webb, R. G., A. W. Garrison, L. H. Keith, and J. M. McGuire. Current Practice in GC-MS Analysis of Organics in Water. EPA-R-73-277, U.S. Environmental Protection Agency, Athens, Georgia, August 1973. 94 pp. (24) Manwaring, J. F., W. M. Blankenship, L. Miller, and F. Voigt. Bis(chloroethyl) Ether in Drinking Water - Its Detection and Removal. J. Amer. Water Works Assoc., 69:210-213, April 1977. (25) Dressman, R. C., J. Fair, and E. F. McFarreh. Determinative Method for Analysis of Aqueous Sample Extracts for Bis(2- Chloro)Ethers and Dichlorobenzenes. Environ. Sci. Technol., 11(7) :719-721, 1977. 11 ------- TABLE 6. HALOETHERS DETECTED IN WATER Concentration, Location Reference Bis(2-chloroethyl) ether Bromophenyl phenyl ether Bromophenyl phenyl ether Bis(2-chloroethyl) ether Bis (2-chloroisopropyl) ether Bis(2-chloroethyl) ether Bis (2-chloroisopropyl) ether r -" _a a _a _a a _a 0.5 to 5.0 2.0 Kanawha River, West Virginia New Orleans drinking water Jefferson Parish No. 2 Jefferson Parish No. 2 Jefferson Parish No. 2 Evansville, Indiana drinking water Evansville, Indiana Ohio River, Evansville 18 19 20 20 20 21 21 Bis(2-chloroethyl) ether Bish(.2-chloroisopropyl) ether Bis(2-chloroethoxy) methane Bis(2-chloroethyl) ether Bis(2-chloroisopropyl) ether Bis(2-chloroethyl) ether Bis(2-chloroethyl) ether Bis(2-chloroethyl) ether Bis(2-chloroisopropyl) ether 0.07 0.16 0.12 0.18 0.05 0.03 140,000 160 _a 10 0.4 0.01 to 0.36 0.02 to 0.55 Carrollton Jefferson Parish No. 1 Jefferson Parish No. 2 Carrollton Jefferson Parish No. 1 Jefferson Parish No. 2 Synthetic rubber plant Synthetic rubber plant Glycol plant thickening and sediment pond Philadelphia Northeast water treatment plant Delaware River, Philadelphia Various cities during NOMS . Various cities during NOMS 22 22 22 22 22 22 23 23 23 24 24 25 25 Detected but not quantified. ------- paragraphs; where appropriate, the gas chromatographic column and type of detector are described. Direct Analysis— A number of laboratory studies, primarily involving the formation or hydrolysis of BCME, have utilized the direct analysis of air and water samples (12-15). In these studies, a semi-membrane silicone fiber probe was used and connected directly to a high- resolution mass spectrometer. Direct analysis for fumigant gases was performed by Berck (26) using a (1.8 m x 4 mm) stainless-steel column packed with 10% SE-30 on Diatoport S. The gases were analyzed for BCEE, and a thermal conductivity detector was used. Absorbers— A variety of absorbers have been used to collect haloethers (primarily BCME ) from air. The absorbers were subsequently thermally desorbed onto a gas chromatographic column connected to a low- or high-resolution mass spectrometer. Table 7 cites the haloethers collected, the abosrber used for collection, the gas chromatographic column employed, and the literature refer- ence from which these data were taken (10, 11, 27-35). (26) Berck, B. Determination of Fumigant Gases by Gas Chromato- graphy. J. Agr. Food Chem., 113:373-377, 1965. (27) Collier, L. Determination of Bischloromethyl Ether in the ppb Level in Air Samples by High Resolution Mass Spectro- scopy. Environ. Sci. Technol., 6 (10) :930-932, 1972. (28) Shadoff, L. A., G. J. Kallos, and J. S. Woods. Determina- tion of Bis(chloromethyl) Ether in Air by Gas Chromato- graphy - Mass Spectrometry. Analytical Chemistry, (45(14): 2341-2344, 1973. (29) Ellgehausen, D. Determination of Volatile Toxic Substances in the Air by Means of a Coupled Gas Chromatograph - Mass Spectrometer System. Analytical Letters, 8(l):ll-23, 1975. (30) Sawicki, E. Bis(chloromethyl) Ether (Bis-CME) in Air Analytical Method. Health Lab Sci., 12:403-406, 1975. (31) Pellizzari, E. D., B. H. Carpenter, J. E. Bunch, and E. Sawicki. Collection and Analysis of Trace Organic Pol- lutants in Ambient Atmospheres - Techniques for Evaluating Concentration of Vapors by Sorbent Media. Environ. Sci. Technol., 9(6):552-555, 1975. (32) Pellizzari, E. D., B. H. Carpenter, and J. E. Bunch. Col- lection and Analysis of Trace Organic Vapor Pollutants in Ambient Atmospheres, Thermal Desorption of Organic Vapors (Continued) 13 ------- TABLE 7. ANALYSIS OF HALOETHERS IN AIR WITH POROUS POLYMER ABSORBER/GAS CHROMATOGRAPHY/MASS SPECTROMETRY Haloether Absorber Gas chromatographic column Reference BCME Porapak Q BCME Ascarite/ Chromosorb 101 BCME Chromosorb 101 BCME Porapak Q BCME Porapak Q BCME Chromosorb 101 BCME, BCEE Chromosorb 101 Chromosorb 104 Tenax-GC Porapak Q Activated carbons 20% Carbowax 600 on Chromosorb W Carbowax 400/Porasil C Oxypropionitrile/ Porasil C 25% Dldecylphthalate on Chromosorb P 20% Tricresyl phos- phate on Chromo- sorb W BCME Porapak Q Tenax Chromosorb 101 Chromosorb 104 BCME, BCEE Tenax-GC BCME Porapak Q Chromosorb 101 Chromosorb 11 (1.22 m x 2 mm or 4 mm) OV-225 3% OV-225 on Chromosorb W 80/100 mesh, 3 m x 2 mm 2% DECS on Chromosorb W (HP) 80/100 mesh, 3.6 m x 2.5 mm 27 11 28 10 29 30 31 32 Porapak Q (1.8 m, 50/80 mesh) Chrosorb 101 (1.8 m, 80/100 mesh) 15% Polyterg B-300 on Chromosorb P (3.6 m, 60/80 mesh) 7% OV-225 on Gas Chrom Q (3.6 m, 80/100 mesh) 20% Carbowax 20M-TPA on Chromosorb W (4.6 m, 60/80 mesh) 10% DC-200 (3.1 m) 7% OV-225 (4.6 m) OF-1(1.95%)/OV-17(1.5%)(6.1 m) 1% SP-1000(6.1 mm) 33 Tenax GC (3.6 m x 2.5 nun) 2% DECS on Supelcoport (80/100 mesh)(3.6 m x 2.5 30% Polyethylene glycol adipate on 100/120 mesh Celite (2.7 m x 4 mm) mm) 34 35 14 ------- Two methods based on the use of absorbers for collection utilize solvent for desorption. The National Institute of Occupational Safety and Health (NIOSH) traps BCEE from workplace environ- ments on charcoal. The BCEE is desorbed with carbon disulfide and analyzed using gas chromatography on 10% FFAP on 80/100 mesh, acid-worked, DMCS-treated Chromosorb W (36). An approach developed by MRC for the EPA's Office of Toxic Sub- stances (37) under contract for the analysis of 3-chloroethers (chloroethyl ethyl ether, CEVE, BCEE, BCIPE, BCEXM, and 1,2 bis[2-chloroethoxy] ethane) in air involves the use of Tenax- GC as an absorber. The Tenax-GC tube is then desorbed with methanol and analyzed using gas chromatography/mass spectrometry. The gas chromatographic colmn is Tenax-GC, and the mass spectro- meter is operated in the selected-ion mode. Derivative— The third procedure used to collect and analyze BCME in air is based on derivative formation followed by gas chromatography with an electron capture detector. The derivatives are formed via the reaction in methanol solution between BCME being scrubbed from the air and the sodium salt of 2,4,6-trichlorophenol. Other sodium salts of alkyl or aryl oxides have been used by other (Continued) from Solid Media. Environ. Sci. Technol., 9(6)556-560, 1975. (33) Frankel, L. S. and R. F. Black. Automatic Gas Chromato- graphic Monitor for the Determination of Parts-Per-Billion Levels of Bis(chloromethyl) Ether. Anal. Chem., 48(4): 732-737, 1976. (34) Pellizzari, E. D., J. E. Bunch, R. E. Berkley, and J. McRa-e. Collection and Analysis of Trace Organic Vapor Pollutants in Ambient Atmospheres, The Performance of a Tenax-GC Cartridge Samples for Hazardous Vapors. Analytical Letters, 9(1):45-63, 1976. (35) Evans, K. P., A. Mathias, N. Mellar, and R. Selvester. Detection and Estimation of Bis(chloromethyl) Ether in Air by Gas Chromatography - High Resolution Mass Spectrometry. Anal. Chem., 47 (6) :821-824, 1975. (36) NIOSH Analytical Methods for Set V. NIOSH-SCP V, National Institute for Occupational Safety and Health, Cincinnati, Ohio, December 1976. 43 pp. (37) Sherman, P. L., A. M. Kemmer, L. Metcalf, and H. D. Toy. Environmental Monitoring Near Industrial Sites: 3-Chloroethers. EPA 56/6-78-003, U.S. Environmental Pro- tection Agency, Washington, D.C., 1978. 271 pp. 15 ------- workers. The materials used to form derivatives, the gas chromatographic colmn used for analysis, and the literature reference are listed in Table 8 (38-40). TABLE 8. DERIVATIVE FORMATION FOR ANALYSIS OF BCME IN AIR Derivative reagent Gas chromatographic column -Reference Sodium 2,4,6-trichlorophenate Sodium phenate Sodium methoxide Sodium ethoxide Sodium thiophenate Sodium 2,4,6-trichlorophenate Sodium 2,4,6-trichlorophenate 0.1% QF-1 and 0.1% OV-17 on 100/200 mesh textured glass beads (GLC 100)(1.8 m x 4 mm) LAC-2R446 + 2% H3P04 38 39 40 The major methods for the isolation and concentration of halo- ethers from water have centered around sorption on charcoal or solvent extraction. Methods of analysis are primarily gas chromatography with different detectors. (38) Solomon, R. A. and G. J. Kallos. Determination of Chloro- methyl Methyl Ether and Bis Chloromethyl Ether in Air at the Parts Per Billion Level by Gas-Liquid Chromatography. Anal. Chem., 47(6)955-957, 1975. (39) Solomon, R. A. Detection of Chloromethyl Methyl Ether or Bischloromethyl Ether, U.S. Patent 3,944,389 (to Dow Chem- ical Co.), 16 March 1976. (40) Sawicki, E. Analytical Method for Chloromethyl Methyl Ether (CMME) and Bischloromethyl Ether (BCME). Health Lab Sci., 13:78-81, 1976. 16 ------- Table 9 lists the method of isolation and concentration, the gas chromatography detector, and the literature reference for halo- ethers in water (18, 21, 23, 41). In addition to these standard techniques, Deinzer, et al., tested the use of a cellulose ace- tate reverse-osmosis membrane for concentrating BCEE and BCIPE from water (42). They were not successful in increasing the con- centration of these two compounds in the reject water using that specific membrane. TABLE 9. ANALYSIS OF HALOETHERS IN WATER Haloether Isolation concentration technique Gas chromatograph column Detector Reference BCEE, BCIPE BCEE, BCIPE, BCEXM BCEE, BCIPE BCEE, BCIPE Carbon chloroform extraction Solvent Carbon chloroform extraction Extraction with 5% ethyl ether in hexane Extraction with 15% ethyl ether in hexane BCEM, CEVE Purge and trap BCIPE, BCEE, BPPE BCIPE, BCEE Hethylene chloride extraction 4% FFAP on Chromosorb W (1.8 m x 2.1 mm or 4 mm) 5% SE-30 on Chromosorb W 60/80 mesh (1.8 m x 2 mm) 5% OV-17 on Chromosorb W 60/80 mesh (1.8 m x 2 mm) 4% SE-30 + 6% OV-210 on Gas Chrom. Q (1.8 m x 2.1 mm) 3% SP-1000 on Supelcoport 100/120 mesh (1.8 m x 2.1 mm) 0.2% Carbowax 1500 on Carbopak C (60/80 mesh) (2.4 m x 2.1 mm) + Carbowax 1500 on Chromosorb W (0.3 m x 2.1 mm) 1% SP-2250 on Supelcoport (100/120 mesh) (1.8 m x 2 mm) OV-17 SCOT column IR FID, mass spectrometry FID, mass spectrometry 18 23 21 Microcoulometric, electrolytic conductivity 25 Mass spectrometry 41 Mass spectrometry Mass spectrometry 41 41 (41) Sampling and Analysis Procedures for Screening of Industrial Effluents for Priority Pollutants, U.S. Environmental Pro- tection Agency, Cincinnati, Ohio, April 1977. (42) Deinzer, M., R. Melton, and D. Mitchell. Trace Organic Con- taminants in Drinking Water; Their Concentration by Reverse Osmosis. Water Res., 9:799-805, 1975. 17 ------- SECTION 4 GAS CHROMATOGRAPHY STUDIES Gas chromatography studies were conducted to determine the opti- mum column and conditions for use with haloethers. In addition, electron capture and electrolytic conductivity detectors were studied to determine the most selective and sensitive detector for use with the haloethers. The results of these studies are described in the following subsections. In summary, initial studies of the gas chromatography of the halo- ethers resulted in the selection of SP-1000 on Supelcoport over Tenax-GC as the column of choice. Early studies of detector sensitivity showed that the electron capture detector was more sensitive than the electrolytic conductivity detector. Unfortu- nately, bis(2-chloroisopropyl) ether was found to contain a large number of electron-capturing impurities, while showing no signif- icant impurities with either the electrolytic conductivity de- tector or the flame ionization detector. Because of the BCIPE electron-capturing impurities, work was continued on the electro- lytic conductivity detector and the resulting improvements made possible the use of this detector. With the modified electro- lytic conductivity detector, sensitivity was approximately equal to electron capture and flame ionization detectors but with much greater specificity. The retention time was determined for bis(chloromethyl) ether on the SP-1000 column under the same conditions as those used for the other haloethers. Details regarding this work are provided below. COLUMNS AND CONDITIONS Previous work with similar compounds indicated two columns worthy of more detailed study. The columns were packed with SP-1000 on Supelcoport or with Tenax-GC. Both yielded adequate separations. Conditions found to be optimum for both columns are listed in Table 10. Figures 1 and 2 consist of the chromatograms obtained with SP-1000, and Figures 3 and 4 were obtained with Tenax-GC. Table 11 lists the retention time of the six haloethers on the two columns relative to Aldrin. The superior peak shapes for the haloethers when chromatographed on the column packed with SP-1000 make this the column of choice. An important fact learned during this study concerning SP-1000 was the need to use ultra-high-purity (UHP) grade helium as carrier gas. When regular-grade helium, nitrogen, or argon/methane (95/5) are used 18 ------- TABLE 10. HALOETHER CHROMATOGRAPHIC CONDITIONS FOR COLUMNS PACKED WITH SP-1000 OR TENAX-GC Item Description/value Chromatograph Hewlett-Packard Model 5700 Injection port temperature 250°C Column gas flow 40 nL/min helium Column 1.8 m x 2.1 mm, glass packed with 3* SP-1000 on supelcoport (100/120 mesh) or Tenax-GC (60/80 mesh) Column program SP-1000 - 60°C for 2 min, programmed at 8°C/min to 230°C Tenax - 150"C for 4 min, programmed at 16"C/min to 310°C Detector conditions for Figures 1 through 4 Hall 700 furnace 850"C Hall-electrolyte flow 3.0 mL/min, 40/60 isopropyl alcohol/ water FID temperature 300"C Gases Column effluent 40 mL/min helium split with 26 mL/min to Hall and 14 mL/min to FID Hall 24 mL/min helium makeup; 50 mL/min hydrogen FID 30 mL/min hydrogen; 240 mL/min air Sample: 1 uL of hexane containing: Compound Concentration, ng/yiL CEVE 262 BCEE 305 BCIPE 275 BCEXM 300 CPPE 250 BPPE 355 Aldrin 275 TABLE 11. RETENTION TIMES OF HALOETHERS ON TWO GC COLUMNS RELATIVE TO ALDRIN Column packed with SP-1000 on Column packed Compound Supelcoport with Tenax-GC CEVE BCEE BCIPE BCEXM CPPE BPPE Aldrin 0.12 0.41 0.37 0.58 0.86 0.94 1.00 0.25 0.50 0.53 0.60 0.81 0.88 1.00 19 ------- K) O TITU- SWf>LE> NIX INJECTED AT METHOD= FID £HJ*GE- IBB 9<10<43 ON JAN 31. 1978 RAM- HFK9>JK, f*C> Pf9'JK a TO 25 NINC1 OIO 3 NIH) 2i.ee BFPE BCEXM ,i3.ee CPPE A" 12 15 Time, min 18 21 24 Figure 1, Chromatogram of haloethers on column packed with SP-1000 on Supelcoport and using flame ionization detector (see Table 10 for conditions). TITLE- SAMPLE' NIX INJECTED AT 9'19'43 OH JAN 31. 1978 METHOD* HALL RAH> RHeW'JK, PRC- JKH9-JK EHUWGE- 1 TIME- e TO 23 HINC1 OIO 3 NIN) BCEE CEVE Hexane .83 » 9.32 Aldrin BCIPE 1 I 1 BPPE .21 I 41 1 BCEXM fl «.ee I 1 CPPEll I tL •«]< V— JV ILJvJ 22.96 15 s 0 3 69 12 15 1» 21 24 Time, min Figure 2. Chromatogram of haloethers on column packed with SP-1000 on Supelcoport and using Hall electrolytic conductivity detector (see Table 10 for conditions). ------- TITLE- SAMPLE- HIX-1/1 INJECTED AT 12'11'89 ON FEB 6, 1978 METHOD. FID (MM- RflW'JK PRC' PFIW'JK ENLARGE- 208. TIME' 8 TO 21 NINCt 010- 3 MIN) BPPE 6.0 Aldrin .16.27 TITLE- SNO RTS* SftnPtE- HIX-1/1 INJECTED AT 13'33'W ON FEB 6. 1978 METHOD' HALL RAM> RH189-JK PRC- FH12 ENLARGE- 48 TIME- 8 TO 25 HIHO 010- 3 «IH> 12 15 18 21 12 15 Time, min 18 21 24 Figure 3. Chromatogram of haloethers on column packed with Tenax-GC and using flame ionization detector (see Table 11 for conditions). Figure 4. Chromatogram of haloethers on column packed with Tenax-GC and using Hall electrolytic conduc- tivity detector (see Table 11 for conditions). ------- as carrier, the peak shape of the haloethers degrades with time. With the use of UHP-grade helium, no peak shape degradation was observed for the SP-1000 column when used continuously for thirty days. After the initial column and conditions study was completed, additional work refined the chromatographic conditions using the SP-1000 column. The new conditions reduced the chromatographic run time from over 21 minutes to less than thirteen minutes. There was no sacrifice in peak separation in spite of a 40% savings in time. The neW chromatographic conditions are listed in Table 12, with the resulting chromatogram in Figure 5. TABLE 12. NEW HALOETHER CHROMATOGRAPHIC CONDITIONS FOR COLUMN PACKED WITH SP-1000 Item Description/value Chromatograph Hewlett-Packard Model 5710 A Injection port temperature 250°C Auxiliary transfer line 250°C Column gas flow 30 mL/min UHP-grade helium Column 1.8 m x 2.1 mm, glass, packed with 3% SP-1000 on Supelcoport (100/120 mesh) Column program 100°C for 4 min, programmed at 16°C/min to 230°C Detector conditions for Figure 5 Hall 310 furnace 850°C Hall-electrolyte flow 0.5 mL/min, 50/50 ethyl alcohol/water Hydrogen flow 70 mL/min Sample: 1 yL of acetone containing: Compound Concentration, ng/yL BCIPE 50 BCEE 62 BCEXM 53 CPPE 50 BPPE 52 22 ------- 0.39 HEXANE BCBXH 7.80 BPPE CPPK 12.54 11.57 - JL_IL_ 8 10 12 Tine, min 14 16 Figure 5. Chromatogram of haloethers with new conditions (see Table 12 for conditions). INITIAL DETECTOR STUDIES In the early stages of this study, the electron capture detector seemed to be the best candidate for final selection as the method for haloether detection. Linearity was very good for all com- pounds being studied. Figure 6 shows an example of this linear- ity for CPPE. Although the sensitivity and reproducibility data (see Tables 14 and 15 near the end of this section) are not impressive, it was felt that refinement in technique and condi- tions could improve results to the desired level. The greatest problem with the electron capture detector was created by one of the haloethers. Even the "purest" sample of BCIPE that we could obtain contained over 20 electron-capturing impurities. These - impurities created peaks which interfered with other haloethers. Based on the desire to keep BCIPE in the study, it was decided to investigate other detectors. Data and sample chromatograms from these early studies are shown in Table 13 and Figures 7 and 8. The flame ionization detector (FID) was used routinely during the selection of optimum conditions and columns. This detector gave very good results in sensitivity, linearity and reproducibility for our pure haloether standards (see Tables 14 and 15). However; knowing wastewaters contain many compounds which would be ex- tracted and detected along with the haloethers, we did not con- sider the FID as our final detector choice because it is so non-specific. 23 ------- 250 200 a 150 100 50 456789 CONCENTRATION, mg/ml 10 11 12 Figure 6. Calibration curve for CPPE. TABLE 13. HALOETHER CHROMATOGRAPHIC CONDITIONS FOR COLUMN PACKED WITH SP-1000 AND USING ELECTRON CAPTURE DETECTOR Item Description/value Chromatograph Hewlett-Packard Model 5713 Injection port temperature 250°C Electron capture detector temperature Column Column program Gases Column 300 "C 1.8 m x 2.1 mm, glass packed with 3% SP-1000 on supelcoport (100/120 mesh) 60"C for 2 min, then programmed at 8°C/ min to 230"C Electron capture makeup Sample: 2 yL of hexane containing: Ether Concentration, 40 mL/min ultra-high-purity helium 20 mL/min, 5% methane in argon CEVE BCEE BCEXM CPPE BPPE 205 138 133 50 8 24 ------- M Ul s a a o 24 Figure 7. Chromatogram of BCIPE on column packed with SP-1000 and detected simultaneously using FID and electron capture detectors, showing electron-capture impurities. TITLE STORAGE $TABILITV-H»Y SAMPLE HEXANE tNUL INJECTED AT 9 48 W ON AP* «. 19T» METHOD EXT1 ft* t«ei7«-IK ft? EKJ^GE- 1 TIME' 0 TO Zl.9 HIKI OIO 3 MM) BPPE 21.20 BCEXM 13.26 CPPE 19.45 12 15 Time, rain IS 21 24 Figure 8. Chromatogram of haloethers on column packed with SP-1000 and detected using an elec- tron capture detector. ------- The early work with the model 700 Hall electrolytic conductivity detector was not very promising. If this detector were to be used, sensitivity and reproducibility would have to be improved (see Tables 14 and 15). It was difficult to stabilize the unit each day, and linearity of results over a wide range of concen- trations was not possible. In spite of these problems, it was decided to be worthwhile to develop the system because of the Hall's specificity. A number of changes were made on the model 700 Hall detector which significantly improved the sensitivity and the reproduci- bility of the detector (see Tables 14 and 15). The major changes were: • The addition of a glass-lined, heated (^275°C) collection port at the exit of the chromatograph as well as the heat- ing of the transfer line. • The use of ethanol/water or absolute ethanol as the electro- lyte solution instead of isopropanol/water. • Modifications on the exit end of the quartz tube, such as the use of Teflon instead of stainless steel and the insertion of the tube from the detector cell up into the end of the quartz tube. The Hall detector still does not give linear results over a wide range of concentrations, but careful calibration will give re- liable values for the haloethers. The greatest advantage of this system is the specificity for the compounds of this study. Fig- ure 9 shows a sample chromatogram from the modified model 700 Hall detector. TABLE 14. SENSITIVITY FOR HALOTHERS 5 x noise, Electron Haloether CEVE BCIPE BCEE BCEXM CPPE BPPE capture 40 9. 28 26 12 1. 0 6 FID 1 0 1 1 0 0 .5 .65 .25 .75 .25 .15 Hall 8. 46 8. 240 5. 28 ng Modified 700 4 6 8 Hall 0. 0. 0. 0. 1. 0. 700 5 45 25 20 1 55 26 ------- TABLE 15. REPRODUCIBILITY DATA Standard manual injection - • 1 yL solution containing: CEVE BCIPE BCEE BCEXM CPPE BPPE 105 ng 100 ng 98 ng 96 ng 100 ng 99 ng Relative standard deviation/ percent Haloether Electron capture FID Hall 700 Modified Hall 700 CEVE BCIPE BCEE BCEXM BPPE 10.4 6.3 11.1 15.5 7.0 42.5 1.2 1.2 0.8 1.2 23.1 11.2 22.1 37.7 28.7 6.4 4.5 3.4 3.7 3.9 Hall 310 1.9 2.4 4.6 2.4 1.3 Caused by the venting of the solvent peak. u B* u 8: 12 15 18 Time (min) 21 24 27 Figure 9. Chromatogram of haloethers on the modified Hall Model 700 detector. 27 ------- The final detector used was the model 310 Hall electrolytic con- ductivity detector. As with the model 700 Hall, many alterations were needed before good results were possible. Results from the model 310 are comparable to those from the modified model 700 (see chromatogram in Figure 5). Detector Summary and Recommendation Each of the detectors discussed in this section has its own limi- tations; EC - interference peaks from BCIPE, FID - nonspecific, both Hall models - nonlinear over a wide range. The final selection of a detector must be based on the quality of results needed and the type of sample being analyzed. We have no control over the number or types of compounds in the wastewaters to be analyzed. Therefore, we feel it is essential to select a detec- tor that is as specific as possible for our compounds. The Hall detector models are the most specific detectors discussed. The Hall's major problem (nonlinearity over wide ranges) can be overcome with careful calibration techniques, while the problems of the other detectors have no obvious solutions. We feel the electrolytic conductivity detector is the best choice for halo- ether detection. Bis(chloromethyl) Ether Bis(chloromethyl) ether was analyzed by gas chromatography using a column containing 3% SP-1000 on Supelcoport (100/120 mesh). The BCME elutes at approximately 2.7 minutes under the conditions normally employed for the haloethers (60°C for 2 minutes, then programmed at 8°C/min to 230°C and held at that temperature for 8 minutes). There was no problem in separating the BCME from the CEVE, as shown in Figure 10. 2.K z.r Figure 10. Chromatogram showing the response of BCME in comparison to three other haloethers on column packed with SP-1000 on Supelcoport. 28 ------- SECTION 5 EXTRACTION STUDIES Extraction studies for the six haloethers using spiked laboratory samples were conducted at three pH's (2, 7, and 10) with three solvents (methylene chloride, 15% ethyl ether in hexane, and pen- tane). Due to problems caused by the presence of a large number of electron-capturing impurities in BCIPE, it was necessary to perform a separate extraction study for the compound. The pro- cedures used for the studies are described in detail for the pH 2 studies. The pH 7 and pH 10 extractions were conducted in exactly the same manner except for the composition of the buf- fers, which are described below. Extraction at pH 2 Three one-liter buffered deionized water solutions were spiked with 10 yL of a standard solution of five of the haloethers (CEVE, BCEE, BCEXM, CPPE, and BPPE) in acetone. The deionized water was prepared by adding 0.82 mL of concentrated hydrochloric acid to one liter of water (0.01M). The concentrations of the five halo- ethers in the acetone spiking solution were 8.2 mg/mL of CEVE, 5.5 mg/mL of BCEE, 5.3 mg/mL of BCEXM, 0.32 mg/mL of BPPE, and and 2.0 mg/mL of CPPE. Three additional one-liter solutions of deionized water were spiked with 100 yL of an acetone solution containing 9.24 mg/mL of BCIPE. The solutions were extracted immediately after spiking with three 60-mL portions of pentane. These extracts were combined and passed through a 2-gram bed of sodium sulfate which was held in a glass funnel by glass wool. The dried extracts were' then evaporated using Kuderna-Danish evaporators to a volume of %4 mL. These concentrates were then transferred to tared, Viton, septum- capped vials and reweighed. The final volume of the concentrates was determined by dividing the net weight of the concentrates by the density of pentane. The three extraction concentrates from the solutions spiked with the five haloethers (CEVE, BCEE, BCEXM, CPPE, and BPPE) were analyzed onal.8mx2.lmm glass column packed with 3% SP-1000 on (100/200 mesh) Supelcoport, with an electron capture detector. The three remaining concentrates from solutions spiked with BCIPE were analyzed onal.8mx2.lmm glass column packed with 29 ------- (60/80 mesh) Tenax-GC, with a flame ionization detector. In both analyses, the areas of the peaks were integrated and the percent recovery determined by comparing the areas of the concentrates with those of standard samples. Calibration curves were deter- mined for all six haloethers with the appropriate detector, and the curves were found to be linear in the concentration range used. The extraction study was repeated for two other solvents (15% ethyl ether in hexane, and methylene chloride) using the same procedure as that described above for pentane. However, for these other solvents, the hexane was solvent exchanged for methylene chloride during the Kuderna-Danish evaporation. This solvent exchange was acomplished by allowing the methylene chlo- ride to evaporate to ^6 mL, adding 20 mL of hexane and evapora- ting to 6 inL, and finally adding 10 mL of hexane and allowing the solvent to evaporate to M' mL. Extraction at pH 7 Extraction studies at pH 7 were performed in the same manner as those studies at pH 2 except for the buffered deionized water. The buffered deionized water for the pH 7 studies was prepared by mixing 500 mL of 0.1M potassium dihydrogen phosphate with 291 mL of 0.1M sodium hydroxide and diluting to one liter. Extraction at pH 10 Extraction studies at pH 10 were also performed in the same manner as those at pH 2 and pH 7 except for the buffered deion- ized water composition. The buffered solutions for the pH 10 studies were prepared by mixing 500 mL of 0.025M borax (sodium tetraborate) with 183 mL of 0.1M sodium hydroxide and diluting to one liter. Results The analytical results of the extraction studies are presented in Table 16. Each value listed for "percent recovered" repre- sents an average of three different extractions at a given pH and for a given solvent. These results were analyzed using anal- ysis of variance (ANOVA), and the resulting F values for each haloether and the average are listed in Table 17. For CEVE, pH was the only variable which contributed significantly to the total variance. For BCIPE, both pH and solvent were significant contributors to the variance. For the four other haloethers, only the solvent contributed to the variance. These ANOVA results, together with the data presented in Table 16, indicate that the best average recoveries of the haloethers are achieved using methylene chloride as solvent. 30 ------- TABLE 16. RESULTS OF EXTRACTION STUDIES Solvent 15% Ethyl ether in hexane PH 7. 7 10 Haloether CEVE BCIPE BCEE 8CEXM CPPE BPPE CEVE BCIPE BCEE BCEXM CPPE BPPE CEVE BCIPE BCEE BCEXM CPPE BPPE Percent recovered (average) 29.6 66.4 66.9 55.9 67.3 57.4 65.9 88.5 63.7 68.0 65.1 57.1 44.2 61. 7C 59.9 54.5 54.4 52.7 RSD,3 % 32.4 21.8 16.3 15.0 9.8 8.7 16.5 7.6 3.1 14.5 12.5 12.7 29.8 __ 20.8 24.7 30.8 30.4 Methylene Percent recovered (average) 31.3 51.2 69.7 83.2 82.9 68.9 70.7 61.6 93.2 88.0 85.6 81.3 55.0 92.1 101.6 75.3 93.2 82.9 chloride RSD,3 % 9.5 21.5 20.3 11.2 12.7 14.6 31.5 8.2 1.6 7.3 6.8 6.3 41.2 5.2 8.1 8.5 4.3 1.9 Pentane Percent recovered (average) 37. 8L 22. lb 43.4 50.5 62.8 55.8 . 61.7 76.2 46.1 43.3 61.1 63.1 30.7 63.0 42.7 38.4 66.1 67.3 RSD,3 % 32.1 — 9.8 13.9 20.0 21.3 47.3 10.7 8.7 27.8 12.5 6.5 13.8 10.8 5.3 6.4 2.3 0.56 RSD = relative standard deviation. Value for one extraction. °Average of two extractions. TABLE 17. RESULTS OF ANOVA FOR SOLVENT EXTRACTION STUDIES Degrees Variable of freedom Solvent j PH 1 Replicates 2 2 2 T values 3 3 3 .55 .55 .55 CEVE 0.69 9.64 1.22 BCEE 72.05 3.10 1.49 BCEXM 34.8 2.68 1.11 F values CPPE 20 0 0 .65 .01 .005 BPPE 16.6 1.97 0.61 BCIPE 18.1 10.1 0.73 Average 27.1 4.6 0.86 ------- The average recoveries for all six haloethers combined using methylene chloride as a solvent were 64.5%, 81.0%, and 83.4% at pH 2, pH 7, and pH 10, respectively. A t-test was employed to determine whether these means are statistically different from each other at the 95% confidence interval. The t-test indicated that there is a statistically significant difference in the mean values obtained at pH 2 and pH 7, and also at pH 2 and pH 10. There is, however, no difference in the mean values obtained at pH 7 and pH 10. These statistical analyses indicate that when the six -ethers are extracted by a group, the average variance due to the solvent used, the pH, and the reproducibility constituted approximately 60%, 10%, and 1%, respectively, of the total variance. Chloroethyl Vinyl Ether Because of the general inability to recover CEVE from the samples due to its volatility, it was decided to test CEVE for percent recovery as a purgeable. Hence, 50 yL of a solution containing 1.2 mg/mL of CEVE was injected into 5 mL of organic-free water. The sample was then sparged for 12 minutes with helium at a flow of 40 mL/min. The trapping device was a stainless-steel tube (0.3 m long, 3.2 mm OD) packed with ^0.2 m of Tenax-GC and ^50 mm of silica gel. After sparging, the tube was thermally desorbed onto a Carbowax column held at -40°C. The sample was then an- alyzed by GC/MS using a Hewlett-Packard 5981 GC/MS with a H-P 5934 data system. The conditions for the GC/MS analysis are listed in Table 18. The data for the percent recovery of CEVE by this method are listed in Table 19. A typical chromatogram is shown in Figure 11. TABLE 18. CONDITIONS FOR GC/MS ANALYSIS OF CEVE Item Value/description Carrier gas Temperature program Column and packing Injection port temperature Helium at 30 ml/min -40°C to 180°C/min 1.8 m x 3.2 ram, stainless steel, packed with Carbowax 1500 on Carbopak C; 0.3 m x 3.2 urn, stainless steel, precolumn packed with Carbowax 1500 on Supelcoport 250°C 32 ------- TABLE 19. PERCENT RECOVERY FOR CEVE Area average, Major three masses runs Std. dev. Rel. std. dev., % Std. area Recovery, % 63 106 41906 23974 6592 2980 15.7 12.4 12072 7889 34.7 30.4 IXS'79 FRN 5559 . 1ST SCxPG: 331 X' 1.00 V 1.00 '06. 63. < GAIN 5 B56S TX Figure 11. Typical chromatogram for CEVE with purge and trap system. 33 ------- SECTION 6 PRESERVATION STUDIES Preservation studies were conducted by spiking one-liter solu- tions of buffered deionized water at pH 2, pH 7, and pH 10 with the standard solution of five haloethers (CEVE, BCEE, BCEXM, CPPE, and BPPE) in acetone. The studies were conducted at residual chlorine levels of 0 ppm and 2 ppm and storage tempera- tures of 4°C and 25°C; storage time was seven days. Extraction of the stored solutions was performed using methylene chloride. In the following two sections/ the composition of each sample is described and results are provided for the preservation study. The analytical portion of this study was done using the electron capture detector, therefore BCIPE was excluded because of the number of electron-capturing impurities. Preparation The preservation samples containing 0 ppm residual chlorine were prepared in the same manner as described in the extraction stu- dies (Section 5). Once prepared, each solution was stored in a separate amber glass jug at 4°C or 25°C. Three sample solutions were stored at each set of conditions. The matrix of samples containing 2 ppm of residual chlorine were also prepared in the same manner except that 10 mL of a 432 mg/liter solution of cal- cium hypochlorite was added to each solution before dilution to one liter. This hypochlorite concentration generates a residual chlorine level of 2 ppm. After preparation, these solutions were stored in amber glass jugs as described above. After storage, the solutions were extracted with methylene chlo- ride. The methylene chloride extracts were combined, dried with sodium sulfate, concentrated, solvent exchanged with hexane, and analyzed as described for the extraction studies. Results The analytical results of the preservation studies are presented in Table 20. The "average percent recovered" values listed represent an average of three separate extractions. These data were subjected to ANOVA testing and the results are shown in Table 21. These results are expressed in gross terms with "+" denoting significant contributions of the variable to 34 ------- the variance and "-" showing no significant contribution. The effect of the pH-chlorine level interaction is as important as the main factors, chlorine level and pH. Temperature had no statistical effect on the variability. The pH-temperature inter- action was significant for BCEE and BPPE. TABLE 20. PRESERVATION STUDY RESULTS Chlorine , pH ppm 2 0 2 2 7 0 7 2 10 0 10 2 Haloether CEVE BCEE BCEXM CPPE BPPE CEVE BCEE BCEXM CPPE BPPE CEVE BCEE BCEXM CPPE BPPE CEVE BCEE BCEXM CPPE BPPE CEVE BCEE BCEXM CPPE BPPE CEVE BCEE BCEXM CPPE BPPE At 4 Percent recovered (average ) * 61.7 75.7 78.7 90.6 10.4 78.3 66.2 20.2 18.7 25.3 66.9 65.3 80.3 87.9 * 59.4 68.1 73.2 79.3 37.7 69.8 63.8 66.6 78.4 74.6 55.5 78.8 68.2 60.8 °C RSD,3 % * 23.2 22.0 9.5 7.6 32.3 6.9 22.3 60.5 70.2 31.1 13.0 24.0 10.3 8.8 * 26.5 10.1 5.4 9.8 17.8 26.0 26.0 22.3 18.2 10.5 15.7 4.0 8.2 42.0 At 25 Percent recovered (average) * 76.6 71.0 86.9 91.9 12.5 66.0 89.0 16.4 11.5 28.7 61.4 71.4 74.0 76.5 * 68.7 54.9 70.3 72.5 26.8 53.4 54.0 63.3 57.3 68.6 80.2 70.2 76.9 77.1 °C RSD,3 % * 2.6 3.5 3.8 4.6 20.4 12.4 9.7 61.0 25.2 25.3 8.1 5.7 8.0 2.6 * 17.5 20.8 7.6 6.6 19.3 10.1 20.3 1.5 8.0 13.7 6.5 16.9 9.2 0.76 a RSD = relative standard deviation. * = none detected. 35 ------- TABLE 21. RESULTS OF ANOVA ANALYSIS OF PRESERVATION STUDY RESULTS Variable C12 pH-Cla Compound Temperature level pH level Temperature-pH CEVE - + + + BCEE - - + BCEXM - - ' - CPPE - + + + BPPE - + + + + + = Caused significant variation. - = Caused no significant variation. The data in Tables 20 and 21 show that the only precaution needed for sample preservation is an adjustment of the pH to at least 7 because of the sensitivity of CEVE to acid hydrolysis and the reaction between residual chlorine and BPPE and CPPE at acid pH. Closer examination of Table 20 shows that there is very little difference, if any, between preservation at pH 7 or pH 10. Also, the table shows little difference between preservation at 4°C or 25°C. Since preserving samples in ice for shipping is more time consuming, more expensive, and requires more care; it is fortu- nate that cold storage is not needed. The data for CEVE appears to be most erratic. Much of this vari- ance can be attributed to the extreme volatility of this compound, Recovery of the haloethers increases significantly with the re- moval of CEVE from the list as shown in Table 22. TABLE 22. AVERAGE RECOVERY (%) OF HALOETHERS FROM PRESERVATION STUDY SAMPLES AT NEUTRAL AND BASIC pH At 4°CAt 25°C Chlorine Five Four Five Four pH level, ppm haloethers haloethers haloethers haloethers 7 7 10 10 0 2 0 2 65.2 56.0 63.3 67.6 75.1 70.0 69.6 65.8 62.4 54.6 51.0 74.6 70.8 66.6 57.0 76.1 36 ------- SECTION 7 SOLVENT STABILITY STUDIES Five haloethers were included in the solvent stability study: CEVE, BCIPE, BCEE, BCEXM, and BPPE. CPPE was not included in this study because of its cost ($2/mg or $1,250 for the study). The concentrations used in this study were determined using the data generated in the sensitivity studies for the two detectors (electron capture and electrolytic conductivity). The concen- trations used were equal to 1,000 times the baseline noise for the least sensitive detector. The concentration of the BCEXM was changed to 12.0 mg/mL because sufficient material was not on hand to use the concentration of 48.0 mg/mL in each solvent. Acetone and methanol were the two water-miscible solvents used in this study. These materials were high-purity, "distilled in glass" solvents purchased from Burdick and Jackson. Each solu- tion was made up in a 250-mL glass volumetric flask. Using a 5-mL syringe with 0.05-mL gradations, the compounds were added in the amounts shown in Table 23. Twelve 4-mL aliquots of each solution were quantitatively transferred, using a 4-mL glass pipet, into 5-mL prescored sealable-glass ampules. The ampules were placed in dry ice for cooling and then flame sealed. Immediately after sealing and after storage times of 30, 60, and 90 days, three ampules were opened, placed in septum-capped vials, and analyzed against fresh standards (Table 24) by gas chromatographic conditions are listed in Table 25. Data from the analyses of the solutions are shown in Tables 26 - 33; data from all four storage times are summarized in Table 34. TABLE 23. CONCENTRATIONS OF SOLVENT SOLUTIONS (250 mL) Amount added, Concentration, Compound mL mg/mL CEVE 1.95 8.2 BCIPE 2.10 9.2 BCEE 1.15 5.6 BCEXM 2.50 12.0 BPPE 1.0 5.7 37 ------- TABLE 24. CONCENTRATIONS OF STANDARDS (1 itlL) Compound CEVE BCIPE BCEE BCEXM CPPE Amount added, UL 7.8 8.4 4.2 8.6 4.0 Concentration , mg/roL 8.2 9.2 5.6 10.3 5.7 TABLE 25. HALOETHER CHROMATOGRAPHIC CONDITIONS WITH ELECTRON CAPTURE DETECTOR Item Description/valug Chromatograph Injection port temperature Electron capture detector temperature Column Column program Gases Column: Electron capture makeup: Hewlett-Parkard Model 5713 250"C 300°C 1.8 m x 2.1 mm, glass, packed with 3% SP-1000 on Supelcoport (100/120 mesh) 60°C for 2 min, then pro- grammed at 8°C/min to 230°C 40 mL /min ultra-high- purity helium 20 mL/min, 5% methane in argon TABLE 26. CONCENTRATION OF INITIAL METHANOL SOLUTION USED FOR SOLVENT STABILITY STUDY Concentration Haloether CEVE BCIPE BCEE BCEXM BPPE Concentration added , 8 9 5 12 5 .2 .2 .6 .7 found (avg. of 3 runs) , yg/mL 9. 5. 14 5. 2 7 4 Avg. std. 5 4 4 0 rel. dev. , % .1 .4 .7 .91 38 ------- TABLE 27. CONCENTRATION OF INITIAL ACETONE SOLUTION USED FOR SOLVENT STABILITY STUDY Concentration Concentration found (avg. Avg. rel. added, of 3 runs), std. dev., Haloether yg/mL yg/mL % CEVE BCIPE BCEE BCEXM BPPE 8.2 9.2 5.6 12 5.7 9.9 9.9 6.0 16 5.4 4.9 2.4 3.4 3.8 0.48 TABLE 28. RESULTS OF ANALYSIS OF METHANOL SOLUTION AFTER STORAGE FOR 30 DAYS ConcentrationAvg.rel. Sample (avg. of 3 runs), std. dev., Percent number Haloether ug/mL % change 30 M-l CEVE 0 -a -a BCIPE 9.6 8.0 +4.3 BCEE 5.6 3.4 -1.8 BCEXM 14 2.9 0.0 BPPE 6.3 14 +17 30 M-2 CEVE 0 -a -a BCIPE 9.6 .7.2 +4.3 BCEE 5.6 1.6 -1.8 BCEXM 14 1.4 0.0 BPPE 5.7 9.2 +6.0 30 M-3 CEVE -0 -a -a BCIPE 9.8 4.6 +6.5 BCEE 5.6 1.9 -1.8 BCEXM 15 1.9 +7.1 BPPE 5.9 14 +9.3 aNot determined. 39 ------- TABLE 29. RESULTS OF ANALYSIS OF ACETONE SOLUTION AFTER STORAGE FOR 30 DAYS Sample number 30 A-l 30 A-2 30 A-3 Haloether CEVE BCIPE BCEE BCEXM BPPE CEVE BCIPE BCEE BCEXM BPPE CEVE BCIPE BCEE BCEXM BPPE Concentration (avg. of 3 runs) , vg/mL 11 9.7 6.0 16 6.1 10.1 9.9 6.0 16 6.3 10 10 6.1 16 5.9 Avg. rel. std. dev., % 2.5 2.4 3.7 2.0 12 3.7 0.92 0.3 1.0 13 3.8 1.1 1.8 1.7 14 Percent change +11.1 -2.1 0.0 0.0 +13 . +2.0 0.0 0.0 0.0 +17 +1.0 +1.0 +1.7 0.0 +9.3 TABLE 30. RESULTS OF ANALYSIS OF METHANOL SOLUTION AFTER STORAGE FOR 60 DAYS Sample number 60 M-l 60 M-2 60 M-3 Haloether CEVE BCIPE BCEE BCEXM BPPE CEVE BCIPE BCEE BCEXM BPPE CEVE BCIPE BCEE BCEXM BPPE Concentration (avg. of 3 runs) , yg/mL 0 9.0 5.5 14 5.2 0 9.1 5.4 14 5.2 0 9.3 5.5 15 5.2 Avg. rel. std. dev., % _a 3.2 4. a 4.0 0.4 a 1.2 1.2 1.4 1.3 _a 2.9 2.9 2.6 11 Percent change a -2.2 -3.6 0.0 -3.8 _a -1.1 -5.6 0.0 -3.8 _a +1.1 -3.6 +6.6 -3.8 aNot determined. 40 ------- TABLE 31. RESULTS OF ANALYSIS OF ACETONE SOLUTION AFTER STORAGE FOR 60 DAYS Sample number 60 A-l 60 A-2 60 A-3 Haloether CEVE BCIPE BCEE BCEXM BPPE CEVE BCIPE BCEE BCEXM BPPE CEVE BCIPE BCEE BCEXM BPPE Concentration (avg. of 3 runs) , yg/mL 11 11 6.3 17 4.7 11 10 6.2 17 5.0 9.9 9.5 5.7 15 4.4 Avg. rel. std. dev., % 3.0 0.5 0.9 0.7 0.6 5.9 4.8 5.4 7.7 9.7 1.8 1.6 1.6 1.6 0.5 Percent change +10 +10 +4.8 +5.9 -15. +10 +10 +3.3 +5.9 -8.0 0.0 -4.2 -5.2 -6.7 -23 TABLE 32. RESULTS OF ANALYSIS OF METHANOL SOLUTION AFTER STORAGE FOR 90 DAYS Sample number 90 M-l 90 M-2 90 M-3 Concentration Avg. (avg. of 3 runs), std. Haloether yg/mL CEVE BCIPE BCEE BCEXM BPPE CEVE BCIPE BCEE BCEXM BPPE CEVE BCIPE BCEE BCEXM BPPE 0 11 6. 12 5. 0 12 6. 13 5. 0 12 6. 13 5. 3 8 5 9 6 9 1 1 1 0 _ 3 3 3 1 *•» 0 1 0 0 rel. dev. , % a .4 .5 .9 .6 a .4 .5 .9 .8 a .9 .6 .7 .1 Percent change _a + 20 +11 -14 + 7.4 _a +30 +14 -7.2 +9.3 a +30 +16 -7.2 +9.3 aNot determined. 41 ------- TABLE 33. RESULTS OF ANALYSIS FOR ACETONE SOLUTION AFTER STORAGE FOR 90 DAYS Sample number 90 A-l 90 A-2 90 A-3 Haloether CEVE BCIPE BCEE BCEXM BPPE CEVE BCIPE BCEE BCEXM BPPE CEVE BCIPE BCEE BCEXM BPPE Concentration (avg. of 3 runs) , pg/mL 19 12 5.8 15 6.0 17 11 5.4 13 5.9 15 10 5.6 12 5.7 Avg. rel. std. dev. , % 13 8.7 9.4 11 2.3 6.2 4.1 4.9 4.6 1.4 6.7 4.7 5.4 6.5 3.4 Percent change +92a +21 -3.4 -7.3 +11 +72a +11 -10 -19 +9.3 +52a +1.0 -6.7 -25 +5.6 An unresolved impurity peak eluted as a hump on the trailing edge of the CEVE peak. This caused the computer to inte- grate both peaks together - giving very high values. The hump may be a degradation product of electron capturing impurities. TABLE 34. COMPARISON OF ALL STORAGE TIMES Haloether Initial analysis (avg 3 runs), yg/mL Percent recovery (avg 3 samples) 30 days, 60 days, 90 days, percent percent percent Acetone solution CEVE BCIPE BCEE BCEXM BPPE 9.9 ± 0.5 9.9 ± 0.2 6.0 ± 0.2 16.0 ± 0.6 5.4 ± 0.1 105 ± 3 100 ± 2 100 ± 2 100 ± 2 113 ± 15 107 ± 4 103 ± 3 102 ± 3 102 ± 3 94 ± 3 172 ± 15 111 ± 6 93 ± 6 83 ± 6 109 ± 3 Methanol solution CEVE BCIPE BCEE BCEXM BPPE 9. 5. 14. 5. 2 ± 7 ± 0 ± 4 ± 0. 0. 0. 0. 5 2 6 1 105 ± 98 ± 100 ± 111 ± 7 2 2 14 99 96 100 96 ± 2 ± 3 ± 3 ± 4 130 114 93 109 + + + + 2 2 2 3 42 ------- These statistics show that CEVE is very unstable in methanol. In the initial analysis of the methanol solution, we were unable to arrive at an acceptable concentration for CEVE. The concen- tration of CEVE in methanol was a steadily decreasing value with time. This is due largely to the rapid hydrolysis of CEVE in methanol. By the time the 30 day samples were analyzed, the CEVE had hydrolyzed completely and we were unable to detect any CEVE. Inspection of the data in Table 34 seems to indicate that, except for CEVE, which has since been dropped from the study be- cause of its volatility, the compounds are stable in both acetone and methanol. There is some fluctuation in data of the samples over the varying time periods. This is attributed largely to the impurities in BCIPE and their decomposition and interference. The purest sample of BCIPE that could be obtained still contained over 30 electron-capturing impurities, many of which had retention times near those of the other haloethers. These impurities made the analysis very difficult. Because of these impurity interfer- ences, we were unable to obtain any data regarding the growth of degradation peaks from the original haloether compounds. A sample chromatogram showing the elctron-capturing impurities in BCIPE is shown in Figure 7 (see page 25). 43 ------- SECTION 8 RESIN STUDIES Studies were completed to evaluate the Ambersorb XE-340 and XAD-2 resins for use as concentrators. The two resins were Soxhlet extracted with acetontrile overnight; then Soxhlet extracted with methanol overnight. The resin was then stored in methanol. They were packed into columns (10 mm ID) to a depth of 6 cm. Buffered solutions (of pH 2, pH 7, and pH 10) were prepared in the manner described for the extraction studies (Section 5). One-liter portions of the buffers were then spiked with 100 uL of the concentrated haloether solutions and passed through the resin beds. The beds were then eluted using 150 mL of ethyl ether for the XAD-2 and 150 mL of acetone for the Ambersorb XE-340. Both resins showed the ability to remove the haloethers from water. However, we were unable to strip the haloethers from the Ambersorb XE-340 using either acetone or methanol. The XAD-2 resin worked well on both counts, and the recovery data are presented in Tables 35-37 for pH values of 2, 7, and 10. Due to the high volatility of CEVE, we were unable to recover any appreciable amounts of the compound. Analysis of the data using the F test showed no significant variation in the percent re- covery at any of the three pH values used. TABLE 35. STATISTICAL DATA FOR XAD-2 RESIN AT pH 2 Ether CEVE a BCIPE #1 #2 #3 BCEE # 1 12 #3 BCEXM #1 #2 #3 BPPE fl #2 #3 Perc reoov 62. 71. 79. 40. 47. 47. 59. 67. 77. 69. 81. 81. Average :ent percent •ered recovered 2 7 71.2 7 4 4 45.0 2 3 3 67.9 3 9 7 77.7 6 Rel. std. Std. dev. dev. , % 8.8 12.3 4.0 8.9 9.0 13.3 6.8 8.7 Insufficient data for statistics. 44 ------- TABLE 36. STATISTICAL DATA FOR XAD-2 RESIN AT pH 7 Ether CEVEa BCIPE #1 #2 #3 BCEE # 1 #2 #3 BCEXM #1 #2 #3 BPPE #1 #2 #3 Percent recovered 58.0 76.2 77.8 43.8 56.1 54.3 59.0 69.8 77.9 65.6 67.2 82.7 Average percent Rel. std. recovered Std. dev. dev. , % 70.7 11.0 15.5 51.4 6.7 12.9 68.9 9.5 13.7 71.8 9.4 13.1 Insufficient data for TABLE statistics. 37. STATISTICAL DATA FOR XAD-2 AT pH 10 Ether CEVEa BCIPE #1 #2 #3 BCEE tl #2 #3 BCEXM #1 #2 #3 BPPE #1 #2 #3 Percent recovered 80.9 68.7 83.6 54.8 52.8 65.7 84.8 66.9 81.6 78.0 69.2 78.0 Average percent Rel. std. recovered Std. dev. dev. , % 77.8 7.9 10.2 57.8 7.0 12.0 77.8 9.6 12.3 75.1 5.1 6.7 Insufficient data for statistics. 45 ------- In comparing the resin sorption method of sampling and analysis with the grab and extraction method, we see that each has its own advantages and disadvantages. Grab sampling requires only an adjustment to neutral pH and is therefore very simple in com- parison with pumping an exact amount of sample through the resin tube. Neither method requires refrigeration. The resin method requires considerable preparation i.e., Soxhlet extraction and tube packing. The grab sampling, on the other hand, requires only a one gallon bottle. The resin tubes are smaller and would be easier and cheaper to ship than the gallon bottles which weigh about 9 pounds each. The resin method seems to give recovery data equal to the grab and extraction method. Serious consideration should be given to this method as an alternative. 46 ------- SECTION 9 COLUMN CHROMATOGRAPHY STUDIES Column chromatography studies were conducted to find a chromato- graphic medium sufficient for the removal of potential interfer- ences that may be encountered in actual industrial wastewaters. Column Packed with Florisil Four columns were packed with Florisil and eluted with 200 mL of varying concentrations of ethyl ether in petroleum ether accord- ing to the Method for Organochlorine Pesticides in Industrial Effluents (43). Data for the recovery of the six haloethers from the Florisil columns are listed in Table 38. The samples were run simulta- neously using a Hall Model 700 detector and a FID, as well as a Hall Model 310 detector. Table 38 provides the average recovery for the three detectors. TABLE 38. AVERAGE RECOVERY PERCENT (THREE DETECTORS) OF HALOETHERS ON CHROMATOGRAPHIC COLUMN PACKED WITH FLORISIL AND ELUTED WITH 200 mL 6% ETHYL ETHER IN PETROLEUM ETHER Ether CEVE BCIPE BCEE BCEXM CPPE BPPE Average percent recovered (3 detectors) 6.8 82.1 79.0 71.6 78.5 80.9 Average standard deviation 4.2 2.7 2.6 8.6 4.7 5.2 Relative standard deviation, percent 61. 8a 3.3 3.3 12.0 6.0 6.4 aTwo detectors (not detected on FID due to solvent venting). (43) Determination of Organochlorine Pesticides in Industrial Effluents. Federal Register, 38(125):17319, Part II, Appendix II, 29 June 1975. 47 ------- Most of the haloethers elute in the 6% ethyl ether fraction, as shown in Table 38, with only a slight amount (10%) of BCEXM eluting in the second or 15% ethyl ether fraction. None of the haloethers were detected in the 50% ethyl ether fraction. Fur- ther studies showed that 300 inL of 6% ethyl ether in petroleum ether was sufficient to remove all (including BCEXM) of the haloethers from the column. Column Packed with Silica Gel Columns with 2 cm ID were slurry packed with 20 grams of 60-200 mesh silica gel. The haloether samples were then charged on the head of the column and eluted with varying concentrations (5, 10, 20, 30, and 50%) of methylene chloride in hexane. An experiment was conducted with four identical samples charged on four columns. The FID analyses of the resulting fractions are shown in Table 39. Since the data were so erratic, the analyses were repeated. These results are shown in Table 40. Faced with another set of erratic data, it was decided to start again with a repeat experiment. The resulting fractions were analyzed with the FID (Table 41) and the Hall Model 700 detector (Table 42). The recovery of the six haloethers was very erratic and did not reproduce from one replicate to the other. There- fore, Florisil appeared to be the packing of choice for the sample cleanup. Because of the erratic data shown in Tables 39-42, the use of silica gel was not explored further as a column cleanup media. It was further concluded that 300 mL eluate of 6% ethyl ether in petroleum ether is needed to get complete release of all the haloethers from the Florisil. 48 ------- TABLE 39. RECOVERY OF HALOETHERS ON CHROMATOGRAPH1C COLUMN PACKED WITH SILICA GEL AND ELUTED WITH METHYLENE CHLORIDE IN HEXANE - FIRST FID ANALYSIS Percent recovered Haloether Using 5% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPEa BPPE Using 10% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPEa BPPE Using 20% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPEa BPPE Using 30% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPEa BPPE Using 50% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPEa BPPE Total Elution CEVE BCIPE BCEE BCEXM CPPEa BPPE No. 1 w - 3.4 0.4 100.7 _ 4.9 4.5 0.7 ~ _ 71.3 53.7 — ~ _ 1.9 22.5 0.2 — _ 0.2 — 43.3 — •» 78.3 84.1 44.6 100^.7 No. 2 _ 0.6 8.4 - 101.1 _ 2.9 4.8 - ~ _ 90.8 80.4 — ~ _ 1.8 40.3 68.7 ~ - 0.2 — 27.6 — _ 96.3 133.9 96.3 101.1 No. 3 _ 1.0 14.5 5.4 100.3 - 7.4 4.9 - — * - 99.7 107.8 — ™ - 5.4 50.7 0.8 "™ - - — 8.6 ™ _ 113.5 177.9 1 14.8 100.3 No. 4 - 1.1 - 5.3 100.5 - 19.0 4.9 2.7 " - 87.1 79.5 ~ ~ - 2.5 59.5 46.5 " - 0.2 _ 19.9 " _ 109.9 143.9 74.4 100.5 included. 49 ------- TABLE 40. RECOVERY OF HALOETHERS ON CHROMATOGRAPHIC COLUMN PACKED WITH SILICA GEL AND ELUTED WITH METHYLENE CHLORIDE IN HEXANE - SECOND FID ANALYSIS Haloether Using 5% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPEa BPPE Using 10% MeCl2 in Hexane CEVE BCIPE v BCEE BCEXM CPPEa BPPE Using 20% MeCl2 in Hexane CEVE BCIPE BCEE BCEXM CPPEa BPPE Using 30% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPEa BPPE Using 50% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPEa BPPE Total Elution CEVE BCIPE BCEE BCEXM CPPEa BPPE Percent No. 1 ^ - 4.2 7.9 107.9 _, 4.7 4.2 _ - _ 68.4 51.9 . - _ 2.1 22.7 _ - _ 0.2 - 60.2 - _ 75.4 83.0 68.1 107.9 No. 2 — 0.5 8.2 — 105.7 _ 2.9 4.7 _ - _ 88.9 80.4 _ - _ 1.7 40.0 73.2 - _ 0.3 - 29.3 - _ 94.3 133.3 102.5 105.7 recovered No. 3 — 1.0 - 5.7 101.0 _ 7.1 4.7 _ - _ 96.5 104.8 - - _ 5.8 51.6 0.8 - _ - - 8.8 - _ 110.4 161.1 15.3 101.0 No. 4 ^ 1.0 — 5.6 100.7 — 18.8 4.8 _ - _ 86.6 79.9 _ - _ 2.5 61.0 50.6 - _ _ - 26.6 - _ 108.9 145.7 82.8 100.7 aNot included. 50 ------- TABLE 41. RECOVERY OF HALOETHERS ON CHROMATOGRAPHIC COLUMN PACKED WITH SILICA GEL AND ELUTED WITH METHYLENE CHLORIDE IN HEXANE - THIRD FID ANALYSIS Baloether Using 5% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPE BPPE Using 10% MeCla in Hexane CEVE BCIPE BCEE BCEXM • CPPE BPPE Using 20% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPE BPPE Using 30% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPE BPPE Using 50% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPE BPPE Total Elution CEVE BCIPE BCEE BCEXM CPPE BPPE Percent recovered No. 1 No. 2 No. 3 No. _ .. _ - - _ _ _ - 10.7 40.3 7.7 10 6.4 39.6 5.5 7 3.5 27 - 100 _ -. _ 65.7 36.2 46.5 66.9 35.0 45.2 1 — — — 4.1 _ _ _ _ 44.0 44.5 1.4 — - — 80.8 58.6 66 29.5 2 _ _ _ _ 1.3 _ _ _ 41.3 13.9 6.1 20 65.7 36.8 74 _ _ _ _ _ _ 1.6 0.7 3.5 41.3 94.7 68.8 114 65.7 66.3 177 _ _ _ 120.4 76.5 54.2 10 120.7 76.7 50.7 8 4 _ - - - .3 .0 . .2 .1 - - .0 _ - - - - - _ .6 .3 - - — _ .7 .8 - - — — .5 .2 - .3 .'0 51 ------- TABLE 42. RECOVERY OF HALOETHERS ON CHROMATOGRAPHIC COLUMN PACKED WITH SILICA GEL AND ELUTED WITH METHYLENE CHLORIDE IN HEXANE - (HALL MODEL 700) Haloether Percent recoverea No. 1No. 2No. 3No. 4 Using 5% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPE BPPE Using 10% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPE BPPE Using 20% MeCl2 in Hexane 0.1 0.1 6.9 41.3 4.1 31.9 8.5 5.4 4.3 0.3 0.1 59.6 33.2 48.8 64.1 27.9 35.4 0.1 8.6 4.9 27.2 94.5 1.0 1.0 CEVE BCIPE BCEE BCEXM CPPE BPPE Using 30% MeCla in Hexane CEVE BCIPE BCEE BCEXM CPPE BPPE Using 50% MeCl2 in Hexane CEVE BCIPE BCEE BCEXM CPPE BPPE Total Elution CEVE BCIPE BCEE BCEXM CPPE BPPE - - - 0.1 38.9 38.9 1.7 - 0.1 0.2 0.4 0.4 _ 43.1 2.5 0.1 0.2 0.7 1.7 43.1 2.6 0.6 106.0 108.2 - - - - 0.5 1.1 0.3 82.9 - - 0.7 - _ 14.5 65.1 0.1 - 0.6 8.8 97.4 65.1 0.2 75.7 61.5 1.6 4.3 0.1 0.1 1.3 0.4 _a _a _a _a _a _a _ 6.3 35.9 - 0.2 0.2 1.9 10.6 36.0 0.1 55.7 40.3 1.7 - - - - — _ 68.1 4.1 - - - - 21.9 76.2 - 0.4 0.2 1.7 117.2 174.8 0.1 10.0 6.1 aMissing. 52 ------- SECTION 10 APPLICATION OF METHOD TO WASTEWATER SAMPLES Wastewater samples were obtained from a municipal secondary waste treatment plant and three industrial sites. Each of these four samples was divided into seventeen one-liter portions as shown in Table 43. The spiked samples were one-liter portions of wastewater spiked with 100 uL of a solution containing the con- centrations of the six haloethers listed in Table 44. These concentrations are equal to 1,000 times the baseline noise for either the Hall electrolytic conductivity detector or the flame ionization detector, depending which was least sensitive for that particular haloether. TABLE 43. DISTRIBUTION OF WASTEWATER SAMPLE PORTIONS No< of 1-liter Sample portions Blank 1 Spiked as received for extraction 3 Spiked as received for XAD 3 Blank for XAD 1 Spiked storage 7 days at 4°C, for extraction 3 Spiked storage 7 days at 25°C, for extraction 3 Spiked storage 7 days at 4°C, for XAD 3 TABLE 44. CONCENTRATION OF HALOETHERS IN SPIKING SOLUTION Concentration, Haloether mg/mL CEVE BCEE BCIPE BCEXM CPPE BPPE 1.17 0.97 0.54 1.38 0.3 0.14 53 ------- The samples were extracted with three 60 mL portions of methylene chloride. These three portions were combined, dried with sodium sulfate, concentrated with hexane, and eluted from Florisil using 300 mL of a solution containing 6% ethyl ether in petroleum ether, Then, the samples were again concentrated using K-D evaporator, the volume adjusted to 10 mL, and the samples were ready for analysis. Table 43 shows that the XAD resin sorption method was also used to prepare samples fr analysis. In this procedure the wastewater samples were spiked and run through the resin procedure as described in Section 8. The samples were then either stripped and analyzed immediately or stored for 7 days at 4°C and then stripped and analyzed. All of the analyses were done using the Hall electrolytic con- ductivity detector with a column packed with 3% SP-1000. The municipal wastewater was the first to be analyzed. The results of these analyses are shown in Table 45. This table shows results based on both peak area and peak amplitude as determined by a Hewlett-Packard computer integrator. TABLE 45. RECOVERY OF HALOETHERS FROM WASTEWATER FROM MUNICIPAL SECONDARY WASTE TREATMENT PLANT USING COLUMN PACKED WITH SP-1000 AND HALL ELECTROLYTIC CONDUCTIVITY DETECTOR Sample condition Spiked, as received, extracted (3 samples) Spiked, as received, XAD- 2 (3 samples) Spiked, storage at 25°C, extracted ( 3 samples ) Spiked, storage at 4°C, (3 samples) Haloether CEVE BCIPE BCEE BCEXM CPPE BPPE CEVE BCIPE BCEE BCEXM CPPE BPPE CEVE BCIPE BCEE BCEXM CPPE BPPE CEVE BCIPE BCEE BCEXM CPPE BPPE Based on Percent recovered 9.28 72.17 70.67 75.36 80.93 92.28 8.59 65.33 51.58 64.58 63.30 89.60 21.43 85.00 83.91 85.06 97.50 159.85 11.94 74.61 71.17 73.35 78.22 85.49 peak area Rel. std. dev . , % 32.5 2.9 7.7 4.4 11.6 55.7 35.6 12.0 11.5 13.6 20.1 51.6 22.5 6.4 11.1 8.2 14.4 60.9 16.1 10.1 10.0 6.4 14.4 9.7 Based on peak amplitude Percent recovered 16.66 67.86 64.59 68.36 73.17 81.26 13.31 58.6 47.33 55.95 64.39 . 73.81 21.57 60.77 58.29 59.58 64.59 71.95 20.32 73.73 71.32 74.25 76.72 75.62 Rel. std. dev. , % 4.3 14.3 17.5 19.2 16.2 8.8 10.5 ' 4.6 5.6 4.1 0.3 5.5 9.3 7.6 7.1 9.3 7.1 7.3 2.8 1.2 1.9 ' 1.3 2.0 1.2 54 ------- No final conclusions could be drawn from Table 45 because of the unresolved question of peak areas versus amplitudes. There- fore, an experiment was devised to determine which method of measurement gave more consistent results. The average results for five analyses of a standard sample with the Hall detector are listed in Table 46. An improvement of the relative standard deviation was noted in almost all cases for the results cal- culated using amplitudes as compared to those calculated using areas. Therefore, it was decided to use peak amplitude in the rest of the analyses. TABLE 46. AVERAGE RESULTS FOR FIVE ANALYSES OF HALOETHER STANDARD ANALYZED ON COLUMN PACKED WITH SP-1000 AND USING HALL ELECTROLYTIC CONDUCTIVITY DETECTOR Relative standard deviation, % Haloether CEVE BCIPE BCEE BCEXM CPPE BPPE Concentration , yg/mL 23.4 10.8 19.4 27.6 6.0 2.8 Based on peak area 10.5 3.9 3.2 4.4 7.8 17.8 Based on peak amplitude 4.0 2.2 1.4 2.4 2.2 3.6 After the decision was made to use peak amplitude, the rest of the wastewater analyses were completed. The blank samples (except for source #3) had no response on the Hall detector at retention times which interfered with the haloethers. Source #3 had several interferences which could not be removed with the Florisil cleanup. These interferences were so large and eluted so close to some of the haloethers that they overshadowed all compounds near them. The data for recovery of the haloethers from the wastewaters are shown in Table 47. A "t" test was conducted on the data from the three sites; the values for these sets are listed in Table 48. The "t" values were generated by the following comparison. The mathematical formula used in calculating the "t" values was: - Xa| S2 55 ------- Ul TABLE 47. PERCENT RECOVERIES OF HALOETHERS FROM INDUSTRIAL AND MUNICIPAL WASTEWATER (DETERMINED BY PEAK AMPLITUDE) USING COLUMN PACKED WITH SP-1000 AND HALL ELECTROLYTIC DETECTOR (AVERAGE OF THREE SAMPLES) As received Percent Percent Sample recovered RSD Industrial tl BCIPE BCEE BCEXM CPPE BPPE Industrial 12 BCIPE BCEE BCEXM CPPE BPPE Industrial #3a Municipal fl BCIPE BCEE BCEXM CPPE BPPE 68.0 56.5 60.2 73.3 82.9 62.9 51.2 51.4 70.1 71.7 67.9 64.6 68.4 73.2 81.3 0.4 0.6 2.0 2.8 3.2 1.2 1.7 1.6 0.4 1.0 14.3 17.3 19.2 16.2 8.8 Stored at 25 °C for 1 week Percent recovered 70.9 67.1 70.7 74.1 79.8 64.6 53.0 54.3 71.4 72.1 60.8 58.3 59.6 64.6 72.0 Percent RSD 4.6 5.3 6.3 3.0 2.6 3.0 5.6 4.1 1.4 0.2 7.6 7.1 9.3 7.1 7.3 Stored at 4°C for 1 week Percent recovered 71.2 59.8 67.6 77.1 89.4 65.3 52.7 56.0 72.5 73.3 73.7 71.3 74.3 76.7 75.6 Percent RSD 3.2 5.8 5.5 2.7 4.5 3.4 4.2 5.8 1.4 1.4 1.2 1.9 1.3 2.0 1.2 XAD-2 Percent recovered 76.9 66.4 69.1 77.5 79.2 76.2 64.8 69.3 77.3 76.3 58.6 47.3 56.0 64.4 73.8 Percent RSD 1.4 3.1 2.5 1.8 1.2 2.4 1.2 3.0 3.5 1.7 4.6 5.6 4.1 0.3 5.S XAD-2 stored for 1 week Percent recovered 72.6 61.3 63.8 75.4 84.4 77.7 66.5 70.7 77.3 77.8 63.8 60.6 61.1 68.8 74.9 Percent RSD 2.6 3.8 5.2 2.6 4.7 2.9 2.1 2.0 1.7 1.5 2.3 6.4 4.3 4.1 5.1 Unable to obtain recovery data because of interferences. ------- TABLE 48. "t" VALUES FOR THREE SETS OF WASTEWATER SAMPLES Sample Industrial Industrial Municipal Haloether #1 BCIPE BCEE BCEXM CPPE BPPE #2 BCIPE BCEE BCEXM CPPE BPPE BCIPE BCEE BCEXM CPPE BPPE A/B B/C 1.52 0.23 5.08 2.52 3.90 0.92 0.46 1.71 1.57 3.68 1.43 0.41 0.99 0.14 2.15 0.75 2.16 1.33 0.98 2.01 1.14 4.42 0.91 5.17 1.07 4.22 1.16 4.69 1.81 1.17 A/C 2.39 1.63 3.30 2.22 2.33 1.76 1.08 2.38 3.91 2.23 1.03 1.03 0.65 0.51 1.36 A/D 13.85 8.06 7.41 2.88 2.23 11.53 19.77 4.84 4.57 8.22 1.60 2.60 2.39 1.28 1.57 D/E 3.41 2.82 2.46 1.58 2.20 0.89 0.76 0.97 0 1.72 2.93 4.90 0.57 0.50 0.34 Note: A/B: A/C: B/C: A/D: D/E: Initial (A) Initial (A) 25°C (B) to Initial (A) XAD-2 (D) to to 25°C (B) to 4°C (C) 4°C (C) to XAD-2 (D) XAD-2/week (E) where Xi and X2 are the values of the two samples being compared and Si and S2 are the standard deviation of each. If the "t" value is >2.776, then there is a 95% probability that the two data points are not from the same population. If the "t" value is >8.610, the probability of the two data points being from different populations is 99.9%. Observation of the data from Table 48 seems to indicate that, on the whole, there is not much difference in the samples extracted initially or stored at 25°C and 4°C. There is, however, a statistical difference in the samples analyzed using extraction as opposed to those using the XAD-2 resin. For the two industrial waters, the data indicate XAD concentration results in better recoveries than methylene chloride extraction for most of the haloethers. The method application study determined the effectiveness of the elements in the Phase I research. Experience indicates that most elements of the study have been resolved. The 3% SP-1000 on Supelcoport performed without failure. The Hall detector proved to be a reliable system when proper precuations were observed, and the current GC temperature program gives well defined results within an efficient time frame. Interferences, however, may prove to be a significant limitation to the application of the 57 ------- method. Many non-halogenated compounds were identified in waste- water samples by GC/MS which gave significant peaks on the Hall detector spectra. Wastewater #3 of this study, in particular, confirmed potential interference problems with the extraction- cleanup procedure/detector system used. Since both liquid/ liquid extraction and XAD resin sorption give good recovery data, further research could determine if XAD resins could reduce the interferences which were observed in various waste- water types. It has been shown that the haloethers have no special "storage problems. However, special storage is indicated for biologically active wastewaters because of possible composition changes which may interfere with haloether detection. 58 ------- REFERENCES 1. Durkin, P. R., P. H. Howard, and J. Saxena. Investigation of Selected Potential Environmental Contaminants: Halo- ethers. 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G., A. W. Garrison, L. H. Keith, and J. M. McGuire. Current Practice in GC-MS Analysis of Organics in Water. EPA-R-73-277, U.S. Environmental Protection Agency, Athens, Georgia, August 1973. 94 pp. 24. Manwaring, J. F., W. M. Blankenship, L. Miller, and F. Voigt, Bis(chloroethyl) Ether in Drinking Water - Its Detection and Removal. J. Amer. Water Works Assoc., 69:210-213, April 1977. 25. Dressman, R. C., J. Fair, and E. F. McFarreh. Determinative Method for Analysis of Aqueous Sample Extracts for Bis (2- Chloro)Ethers and Dichlorobenzenes. Environ. Sci. Technol., 11(7):719-721, 1977. 26. Berck, B. Determination of Fumigant Gases by Gas Chromato- graphy. J. Agr. Food Chem., 113:373-377, 1965. 27. Collier, L. Determination of Bischloromethyl Ether in the ppb Level in Air Samples by High Resolution Mass Spectro- scopy. Environ. Sci. Technol., 6 (10):930-932, 1972. 28. Shadoff, L. A., G. J. Kallos, and J. S. Woods. 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Federal Register, 38 (125):17319, Part II, Appendix II, 29 June 1975. 62 ------- APPENDIX A METHOD FOR SAMPLING AND ANALYSIS During the first year of this contract, a complete method was developed for the sampling and analysis of haloether in water and wastewater. The method involves a liquid-liquid extraction using methylene chloride, a solvent exchange with hexane, a Florisil- column chromatographic cleanup procedure, and subsequent analysis by gas chromatography using an electrolytic conductivity detector. A detailed description of this method is provided below. Scope and Application This method covers the determination of the following halogenated ethers in wastewaters: • bis(2-chloroisopropyl) ether (BCIPE) • bis(2-chloroethyl) ether (BCEE) • bis(2-chloroethoxy) methane (BCEXM) • 4-chlorophenyl phenyl ether (CPPE) • 4-bromophenyl phenyl ether (BPPE) Summary This method offers an alternative to the high cost and technical expertise required for the analysis of haloethers by gas chroma- tography/mass spectrometry. The procedure involves a liquid- liquid extraction using methylene chloride and a column chromato- graphic cleanup procedure to remove potential interferences. The samples are then analyzed by gas chromatography using an electro- lytic conductivity detector. Apparatus and Reagents Required For sample extraction, the following are required: • 2,000-mL separatory funnel with Teflon stopcock • 8-ounce Boston round bottle (glass) • 4-dram vials (glass) and caps with conical polyethylene liners 63 ------- • Funnel (60-mm diameter) • Glass beads (2-mm diameter) • Aluminum foil • Kuderna-Danish (K-D) glassware with three-ball (micro) Sny'der column, 500-mL evaporation flask, and 10-mL receiver ampule • Extracting solvent - methylene chloride, "distilled in glass" • Sodium sulfate - (ACS) granular, anhydrous (400°C for 4 hours For chromatographic cleanup, the following are required: • Florisil - 60/100 mesh • Chromatographic columns - 11 mm ID x 300 mm long with 250-ml reservoir (KIMAX) with removal Teflon stopcocks • Glass wool • Kuderna-Danish evaporators with three-ball (macro) Snyder column, 500-mL evaporation flask, and 10-mL receiver ampule • 4-dram vials (glass) and caps with conical polyethylene liners • Septum-capped, glass, sample vials • Sodium sulfate - (ACS) granular, anhydrous (400°C for 4 hours) • Petroleum ether - "distilled in glass" • Ethyl ether - (ACS) reagent grade • Hexane - "distilled in glass" • Laurie acid - reagent grade • Sodium hydroxide - (ACS) reagent grade For sample analysis, the following are required: • Gas chromatograph - temperature programmable • Detector - electrolytic conductivity • Glass column - 2.1 mm ID x 1.8 m long • Column packing - 3% SP-1000 on 100/120-mesh Supelcoport • 10-yl syringe • Carrier and auxilliary gases - helium and hydrogen, pure grades, to preserve column life and avoid interferences • Haloethers standards - Commercial sources of haloether are listed below: 64 ------- Compound Commercial source BCIPE Monsanto Research Corporation, Dayton, Ohio 45407 BCEE RFR Corp., Hope, Rhode Island 02831 BCEXM Pfaltz & Bauer, Stamford, Conn. 06902 CPPE RFR Corp., Hope, Rhode Island 02831 BPPE Pflatz & Bauer, Stamford, Conn. 06.902 • Ethanol - absolute (95%) • Deionized water Sampling and Preservation Procedure Collect samples in one-liter glass containers having an inert liner (Teflon) incorporated in the cap. Prewash and solvent rinse the containers prior to sampling to prevent interferences. Follow conventional sampling practices. Preserve the samples by sealing the bottle lids with a plastic tape and icing for shipment. Sample Extraction Procedure (I) Transfer a measured 1,000 mL of sample from the container to a two-liter separatory funnel. Discard the balance of the water from the container. (2) Add 60 mL of the extracting solvent (methylene chloride) to the sample container and shake vigorously to rinse the bottle thoroughly. Transfer the solvent to the separatory funnel and shake the separatory funnel vigorously for 2 minutes. (3) Allow the two phases to separate and draw the bottom (methy- lene chloride) layer into an 8-ounce Boston round bottle. (4) Repeat Steps (2) and (3) two more times. (5) Plug a standard laboratory funnel with glass wool and fill with approximately 40 mm of anhydrous, granular sodium sulfate. (6) Pass the collected fractions through the sodium sulfate and collect in a 500-mL K-D flask. (7) Rinse the 8-ounce Boston round bottle with approximately 50 mL of methylene chloride, pass it through the sodium sul- fate, and collect in the 500-mL K-D flask. 65 ------- (8) Place two glass beads into the flask, attach the three-ball Synder column to the flask, and place the lower half of the ampule in a steam bath. (9) Insulate the K-D flask with aluminum foil to complete the evaporation in approximately 10-15 minutes. (10) When the volume of the methylene chloride in the flask reaches approximately 10 mL, pour 50 mL of hexane in the top of the Snyder column. Be sure that there is a good washing of the walls of the Snyder column when the hexane passes down to the flask. (11) Evaporate until the ampule is nearly dry. Drain the con- densed vapors from the column into the cooled flask to obtain a final volume of approximately 6 mL. (12) Rinse the Snyder column and walls of the K-D flask with an additional 1 mL of hexane. (13) Remove the Snyder column and flask from the ampule. (14) Transfer the concentrate to a 4-dram vial. Rinse the ampule with 1 mL of hexane and also transfer to the vial. Cap and seal the vial, and store in a cool, dark place to await column chromatography (volume at this point will equal ^8 mL). Quantitation Procedure Complete the quantitative measurements using gas chromatography with an electrolytic conductivity detector at the conditions listed below: Item Value/description Carrier gas Helium at 40 mL/min Temperature program 60°C with 2 min post-script, then 8°C/min to 230°C with a 4-min hold Column and packing 1.8 m x 2.1 mm ID glass packed with 3% SP-1000 on 100/200 mesh Supelcoport Injection port temperature 250°C Detector conditions Tracor Model 700 Hall electrolytic conductivity detector or equivalent halogen selective de- tector. Furnace temperature at 900°C; trans- fer line temperature at 250°C. Absolute ethanol (95%) electrolyte at 0.3 mL/min. 66 ------- Take the vials containing the samples and transfer the contents of each to a 10-mL volumetric flask. Rinse each vial with a total of 1 mL of hexane, transfer to flask and rinse again (rinses should equal ^1 mL). Dilute each sample to exactly 10 mL using more hexane. Transfer the contents to each flask into septum-capped vials for gas chromatography and possible column chromatography. Dilute the standard solutions containing haloethers in the con- centrations shown below, by injecting 80 yL into 4 mL of hexane. The dilute solution is the gas chromatography standard and is 20 times baseline noise. Haloether Concentration/ ug/mL BCIPE 120 BCEE 70 BCEXM 50 CPPE 300 BPPE 150 The above concentrations are equal to 1,000 times the baseling noise for each compound on the Tracer Model 700 Hall electrolytic conductivity detector. Procedure for Removal of Interference Remove interference by Florisil column adsorption chromatography using the following procedure which has been taken from the "Method for Organochlorine Pesticides in Industrial Effluents" (43) . Place a charge of activated Florisil (weight determined by lauric acid value as described in Appendix B) in a glass chromatography column. After settling the Florisil by tapping the column, add about 15 mm of granular, anhydrous sodium sulfate to the top of the Florisil. Pre-elute the column, after cooling, with 50-60 mL of petroleum ether. Discard the eluate. Just prior to exposure of the sul- fate layer to air, quantitatively transfer the sample exact (either the contents of the 4-dram vial or the contents of the 10-mL volumetric flask) onto the column by decantation and sub- sequent petroleum ether washings. Charge eluate to 300 mL of 6% ethyl ether in petroleum ether. Adjust the elution rate to 5 mL/ rain and collect the eluate in a 500-mL K-D flask equipped with a 10-mL ampule. Concentrate the eluate to approximately 6 mL in a K-D evaporation system using a steam bath, transfer to a 10-mL volumetric flask with subsequent rinsings, and dilute to exactly 10 mL. 67 ------- Transfer to a septum-capped vial, and analyze by gas chromatography. Quality Assurance Practice Use standard quality assurance practices with this method. Collect field replicates to validate the precision of the samp ling technique. Analyze laboratory replicates to validate the precision of the analysis. Analyze fortified samples to vali- date the accurracy of the analysis. Calculations and Reporting Determine the concentration in the sample according to the following formula: microgram/liter = where A = ng standard/standard area, integrator counts or cm2 B = sample aliquot area, integrator counts or cm2 Vt = volume of total extract, mL Vi = volume of extract injected, y. Vs = volume of water extracted, £ Report results in micrograms per liter without corrections for recovery data. When duplicate and spiked samples are analyzed, report all data obtained. 68 ------- APPENDIX B STANDARDIZATION OF FLORISIL This rapid method for determining the adsorptive capacity of Florisil is based on the adsorption of lauric acid from hexane solution. An excess of lauric acid is used and the amount not adsorbed is measured by alkali tritration. The weight of lauric acid adsorbed is used to calculate, by simple proportion, the equivalent quantities of Florisil for batches having different adsorptive capacities. Apparatus Required (1) 25-mL buret with 1/10 mL graduations (2) Erlenmeyer flasks - 125 mL narrow mouth and 25 mL glass stoppered (3) Pipette - 10 mL and 20 mL transfer type (4) 500-mL volumetric flasks Reagents and Solvents Required (1) Ethyl alcohol - USP or absolute, neutralized to phenolphthalein (2) Hexane - "distilled in glass" (3) Lauric acid - purified, CP (4) Lauric acid solution prepared by transferring, 10,000 gram lauric acid to a 500-mL volumetric flask, dissolving in hexane, and diluting to 500 mL (1 mL = 20 mg) (5) Phenolphthalein Indicator - dissolve 1 gram in alcohol and dilute to 100 mL 69 ------- (6) Sodium hydroxide - dissolve 20 grains of NaOH (pellets, reagent grade) in water and dilute to 500 m: (IN). Dilute 25 mL of IN NaOH to 500 mL with water (0.05N). Standardize as follows: Weigh 100-200 mg lauric acid into 125 mL Erlenmeyer flask; add 50 mL of neutralized ethyl alcohol and 3 drops phenolphthalein indicator; titrate to permanent end point; calculate mg lauric acid/mL of 0.05N NaOH (about 10 mg/mL). Procedure (1) Transfer 2.000 gram Florisil to 25-mL glass-stoppered Erlenmeyer flasks. Cover loosely with aluminum foil and heat overnight at 130°C. Stopper, cool to room temperature, add 20.0 mL lauric acid solution (400 mg), stopper, and shake occasionally for 15 minutes. Let absorbant settle and pipette 10.0 mL of supernatant into 125-mL Erlenmeyer flask. Avoid inclusion of any Florisil. (2) Add 50 mL of neutral alcohol and 3 drops indicator solution; titrate with o.OSN to a permanent end point. Calculation of Lauric Acid Value and Adjustment of Column Weight (1) Calculate the amount of lauric acid adsorbed on Florisil as follows: lauric acid value = mg lauric acid/gram of Florisil = 200 - [(mL required for titration) x (mg lauric acid/,1 O.OSN NaOH)] (2) To obtain an equivalent quantity of any batch of Florisil, divide 110 by lauric acid value for that bath and multiply by 20 g. 70 ------- |