Environ. 8ci. Technol. 1983, 17, 530-537 (12) Ishiwatari, R.; Takada, H.; Yun, S.-J.; Matsumoto, E. Nature (London) 1983, 301, 599. (13) Eganhouse, R. P. Ph.D. Thesis, University of California, Los Angeles, CA, 1982. (14) Venkatesan, M. I.; Brenner, S.; Ruth, E.; Bonilla, J.; Kaplan, I. R. Geochim. Cosmochim. Acta 1980,44, 789. (15) Reed, W. E.; Kaplan, I. R.; Sandstrom, M.; Mankiewicz, P. API Publ. 1977, No. 4284, 183. (16) Stull, J. Los Angeles County Sanitation Districts, Ocean
Monitoring Group, Whittier, CA, personal communication, 1982.
Barrick, R. C.; Hedges, J. I.; Peterson, M. L. Geochim. Cosmochim. Acta 1980,44, 1348. Huddleston, R. L.; Allred, R. C. Dev. Ind. Microbiol. 1963, 4, 24.
Otvos, I.; Iglewski, S.; Hunneman, D. H.; Bartha, B.; Balthazh, Z.; Palyi, G. J. Chromatogr. 1973, 78, 309. Grubb, H. M.; Meyerson, S. In “Mass Spectrometry of Organic Ions”; McLafferty, F. W., Ed., Academic Press: New York, 1963; p 453. Gledhill, W. E. Adv. A p p . Microbiol. 1974, 17, 265. Swisher,R. D.; Kaelble, E. F.; Liu, S. K. J. Org. Chem. 1961, 26, 4066.
Swisher, R. D., EnvironmentalConsultant, Kirkwood, MO, personal communication, 1982. Hon-nami, H.; Hanya, T. Water Res. 1980,14,1215. Conzett, M., Procter and Gamble Co., Cincinnati, OH, personal communication, 1983. Swisher, R. D. Yukagaku 1972,21, 130. Leidner, H.; Gloor, R.; W h a n n , K. Temide Deterg. 1976, 13, 122.
Eds.; Applied Science: London, 1971, Vol. 2, p 136. (31) Kettenring, K. N. Ph.D. Thesis, University of California, Los Angeles, CA, 1981. (32) Eganhouse,R. P.; Blumfield, D. L.; Kaplan, I. R. University of California, Los Angeles, CA, unpublished data, 1983. (33) Myers, E. P. Ph.D. Thesis, California Institute of Technology, Pasadena, CA, 1974. (34) “The Ecology of the Southern California Bight: Implications for Water Quality Management”:Southern California Coastal Water Research Project, Teckical Report 104, Mar 1973. (35) Swisher, R. D. J. Water Pollut. Control Fed. 1963,35,877. (36) Haydock,I., Los Angeles County Sanitation Districts, Ocean
Monitoring Group, Whittier, CA, personal communication, 1982. (37) Wilson, K. C.; Mearns, A. J.; Grant, J. J. “Southern Cali-
fornia Coastal Water Research Project, Biennial Report, 1979-1980”; p 77. (38) Von Hennig,D. H. Tech. Bull. Shell Chem. Co. 1976,147-76. (39) Moffett, J. G.; von Hennig, D. H. Tech. Bull. Shell Chem. CO. 1981, 583-81. (40) Smokler, P. E.; Young, D. R.; Gordi, K. Mar. Pollut. Bull. 1979, 10, 331. (41) Young, D. R.; McDermott, D. J.; Heesen, T. C. J. Water Pollut. Control Fed. 1976, 48, 1919. (42) MacGregor, J. S. Fish Bull. 1974, 72, 275. (43) MacGregor, J. S. Fish. Bull. 1976, 74, 27. (44) Bascom, W. South. Calif. Coastal Water Res. Proj. Annu. Rep. 1978, 57. (45) McDermott,D. J.; Heesen, T. C.; Young, D. R. South. Calif. Coastal Water Res. Proj. Tech. Mem. 1974,217.
Willetts, A. J.; Cain, R. B. Antonie van Leeuwenhoek 1972, 38, 543.
Swisher, R. D. J. Water Pollut. Control Fed. 1963,35,1557. Cain, R. B.; Wiletts, A. J.; Bird, J. A. In ”Biodeterioration of Materials”; Walters, A. H., Huech-Van Der Plas, E. H.,
Received for review November 24,1982. Accepted April 8,1983. Financial assistance was provided by the Department of Energy (Contract E Y -76- 3- 03- 0034).
Chlorinated Neutral Organics in Biologically Treated Bleached Kraft Mill Effluents Ronald H. Voss Pulp and Paper Research Institute of Canada, Pointe Claire, Quebec, Canada H9R 3J9
Biologically treated combined mill effluents sampled at nine bleached kraft mills were surveyed for chlorinated neutral organic compounds. The test results showed only four main chlorinated compounds: chloroform (7-105 pg/L), a,a-dichlorodimethyl sulfone (64-429 pg/L), a,a,a’-trichlorodimethyl sulfone (0.3-12.4 pg/L), and (tentatively) a,a,a’,a’-tetrachlorodimethylsulfone (0.4-1.1 pg/L). Unlike chloroform, the chlorinated sulfones were found to be relatively resistant to removal by biological treatment in an aerated lagoon. However, preliminary assessment of fish bioaccumulation potential, acute fish toxicity, and Ames mutagenicity indicated that the chlorinated sulfones would have no immediate adverse effect on the aquatic environment.
Introduction The occurrence of chlorinated organic material in spent liquors from the bleaching of kraft pulp is an inevitable result of the common practice of using Clz as a bleaching agent in the first of several consecutive steps in conventional pulp bleaching processes. In recent years, there has been a growing concern about possible adverse effects resulting from the release of such mill-originated chlori530
Environ. Sci. Technol., Vol. 17, No. 9, 1983
nated organics into the aquatic environment. This apprehension probably stems in part from a tendency to associate these chlorinated organic compounds with other chlorinated organics such as DDT and PCBs, whose hazardous effects on living organisms have been well documented. In addition, the concern about the discharge of spent bleaching liquors was heightened by the recent discovery (1,2)that spent chlorination (C) liquors exhibit a strong Ames mutagenic effect. A knowledge of the types and amounts of chlorinated organics present in pulp mill wastewaters will aid in the assessment of the risks involved in releasing such compounds into the aquatic environment. Consequently, considerable research effort has been directed toward the characterization of the chlorinated organic compounds in kraft pulp mill effluents. Two recent reviews by Claeys et al. (3) and by Leach (4) provide a good summary of the state of knowledge (as of late 1979) regarding the identity of chlorinated organics in pulp mill effluents. Until that time, the characterization work had focused mainly on the acidic compounds of low molecular weight consisting principally of chlorinated phenolics and chlorinated resin acids. More recent research, particularly that done by workers at STFI in Sweden (5-8), has provided considerable information about the identity of
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Flgure 1. Structures of compounds representatlve of chlorlnated neutral organics that have been identified in spent kraft bleachlng liquors: I , 2-chloropropenal; 11, chloroform; 111, 1,1,2,3-tetrachloro2-propene: IV, 1,1,3,3-tetrachloroacetone; V, trichloroacetaldehyde: VI, a,adlchlorcdlmethyl sulfone; V I I, chlorinated cyclopentenediones (x = 2, 3); V I II,3-chloro-4-(dichloromethyl)5-hydroxy-2(5H~furanone; IX, Chlorinated thlophenes ( x = 2-4); X, chlorobenzyl alcohol; XI, chlorlnated benzaldehydes (x = 1, 2); X I I , Chlorinated cymendols (x = 1, 2).
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chlorinated neutral organics in kraft bleach plant effluents. Although many of the chlorinated neutral organics occur in the bleach plant effluents at fairly low concentrations, increasing attention is being paid to these compounds because the nonpolar, lipid character of some of them suggests a propensity to bioaccumulate in living tissue. Most of the chemical characterization effort to date has concentrated on the individual process streams from the bleach plant. Selected compounds or classes of chlorinated organic compounds that have been identified in spent bleach plant effluents are listed in Table I. To date over 70 chlorinated neutral organics have been identified in spent kraft bleachings liquors, principally in C-stage effluents. Figure 1gives the structures of several chlorinated neutral organic compounds that have been found in effluents from the kraft bleaching process. Four of the compounds (or classes of compounds) shown in Figure 1 have been found to be mutagenic as determined by the Ames test using Salmonella typhimurium tester strains T A 1535 and TA 100. These are 2-chloropropenal (I (6, 7),3-chloro-4-(dichloromethyl)-5-hydroxy-2( 5 H )-furanone (VIII (37)),tetrachloropropene (111(39-41)), and chlorinated acetones (e.g., IV (6, 7, 35,36,42)). The 2-chloropropenal (I) and the trichlorohydroxyfuranone (VIII) appear to be major contributors to the mutagenicity of kraft chlorination effluents. Although the individual bleaching process streams have been comprehensivelyinvestigated for chlorinated organic compounds, much less work has been done to characterize the chlorinated organics present in bleached kraft total mill effluents (BKME) and, in particular, biologically treated BKME. As suggested by Claeys et al. ( 3 ) )the chemical analysts' bias for working with the individual bleaching process streams is related in part to convenience since the components are present at higher concentrations and interferences from other (particularly pulping) processes are Environ. Sci. Technol., Vol. 17, No. 9, 1983 531
Table 11. Chlorinated Organics Identified in Biologically Treated BKME compound 2,4-dichlorophenol 2,4,6-trichlorophenol 2,3,4,6-tetrachlorophenol pentachlorophenol dichloroguaiacol (3 isomers) trichloroguaiacol ( 3 isomers) chlorodehydroabietic acid ( 2 isomers) chloroform
ref compound Chlorinated Phenolics 3, 43 tetrachloroguaiacol 3, 21, 25, 43 dichlorocatechol 21, 25, 43 trichlorocatechol ( 2 isomers) 3, 43 tetrachlorocatechol 21,43 trichlorosyringol 3, 10, 21, 25, 43-45 Chlorinated Resin Acids 3, 21, 44, 45 dichlorodehydroabietic acid Chlorinated Neutrals 3, 32 tetrachloroacetone
avoided. In addition, most of the studies have been directed toward identification of those compounds responsible for observed biological effects such as acute fish toxicity (11,13,16,17,20-22,27) and Ames mutagenicity (1,2,6, 7,34-42). In particular, kraft chlorination liquor has been the subject of extensive study because this effluent has been found to be the major source of mutagenic substances produced in the kraft bleachery (1,2). Although more than 100 chlorinated organic compounds have been identified in untreated process effluents from the kraft bleaching process, far fewer chlorinated organics have been found in biologically treated combined bleached kraft mill effluent. As shown in Table 11, the chlorinated organics detected to date in biologically treated BKME consist mainly of chlorinated acidic compounds, viz., chlorinated dehydroabieticacids and chlorinated phenolics. Only two chlorinated neutral organic compounds have been reported to be present in biotreated BKME, chloroform and tetrachloroacetone. The results of a study undertaken to provide further information regarding the identity of chlorinated neutral organics in biologically treated BKME are discussed in this paper. This study has focused on biotreated BKME. From the standpoint of assessing the impact of chlorinated organics of bleach plant origin on the receiving environment, knowledge about the chlorinated organic content of the wastewater leaving the "factory gate" is more relevant than information about chlorinated organics in the individual bleaching process streams. To provide information generally applicable to biologically treated BKME, we undertook a survey of aerated lagoon outlet samples from nine softwood bleached kraft pulp mills located across Canada. These samples were collected during late fall and early winter. Experimental Section Apparatus. The gas chromatograph (GC) was a Hewlett-Packard Model 5880 equipped with a 63Nielectron capture detector (ECD) and a split/splitless capillary column inlet system. A Hewlett-Packard Model 5985A gas chromatograph/ mass spectrometry (GC/MS) system with computerized data processing was used. A glass jet separator with makeup gas addition was used as an interface to couple capillary GC columns to the quadrupole mass spectrometer. A 15 m X 0.25 mm i.d. fused silica capillary column wall-coated with SE-54 (J & W Scientific, Orangeville, CA) was used for GC and GC/MS analysis. Instrumental Conditions. Two setxi of GC conditions were used: (1)For chloroform analysis, the column temperature was 50 "C; injector, 250 "C; detector, 250 OC; carrier gas, helium at 55 kPa; ECD auxiliary gas, argon (%%)/methane (5%) with a flow rate of 44 mL/min. A split injection with 1:40 split ratio was used (column flow 532
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ref 3, 10, 21, 25, 43-45 21, 25 21, 25, 43 21, 25, 43 21
3, 21, 44, 45 21
= 0.6 mL/min; split vent flow = 24 mL/min). (2) For chlorinated neutrals analysis, the column temperature was 45 "C (held for 1 min) and then programmed to 120 OC at 15 "C/min followed immediately by a 4 OC/min temperature increase to 190 "C; injector, 250 OC; detector, 250 "C; carrier gas, helium at 55 kPa; ECD auxiliary gas, argon (95%)/methane (5%) with a flow rate of 44 mL/min. A splitless injection technique was used. For GC/MS analysis, a 15-m SE-54 fused silica capillary column was connected to the quadrupole mass spectrometer via a glass separator. Helium makeup gas at a flow rate of 30 mL/min was added at the capillary column outlet. The mass spectra were produced by electron impact at 70 eV. The jet separator interface temperature was 250 "C, and the ion source temperature was 200 "C. Preparation of Samples for GC Analysis. Chloroform Analysis. A rapid and simple method based on liquid extraction with subsequent GC/ECD analysis (46-48) was used to determine the chloroform concentration in the aerated lagoon outlet samples. A 5-mL aliquot of the effluent sample was transferred into a 7.4-mL screwcap bottle with a Teflon-lined cap. Upon addition of 1mL of isooctane (Baker Resi-analyzed) containing 0.648 ng/pL tetrachloroethylene (Aldrich, spectrophotometric grade, gold label) as internal standard, the bottle was capped tightly and then shaken vigorously for 1 min. A 2-kL portion of the extract was analyzed by split capillary GC/ECD (see GC conditions described above). Chlorinated Neutral Organic Analysis. The less volatile (relative to chloroform) chlorinated neutral organic constituents in biologically treated BKME were isolated by solvent extraction with a more polar solvent, methyl tert-butyl ether, and determined by analysis of the (unconcentrated) solvent extract by splitless capillary GC with electron capture detection. A 10-mL aliquot of effluent adjusted to a pH of ca. 1 2 was extracted in a separatory funnel with 10 mL of methyl tert-butyl ether (Burdick & Jackson, distilled in glass) containing 0.568 ng/pL of 1,2,4-trichlorobenzene (RFR Corp.) as an internal standard. A 2-pL portion of the solvent extract was subsequently analyzed by splitless capillary GC/ECD (see above for GC conditions for analysis). Quantification was based upon the internal standard method using (electronically integrated) peak areas relative to the internal standard and appropriate relative response factors. Calibration of the gas chromatograph (i.e., determination of response factors and retention times relative to the internal standard) was performed by injecting a standard mixture in methyl tert-butyl ether containing known amounts of the reference compounds in addition to the internal standard. An assumed response factor (='/2 the response factor for a,a,a'-trichlorodimethyl sulfone)
Table 111. Concentration of Chloroform in Biologically Treated BKME Samples [ CHCL I," [CHCLI," mill pg/L mill MIL A 105 G 102 B 79.8 H 21.2 C 13.8 I 9.5 D 23.9 av 43.0 E 6.5 lagoon inlet (B)b 211 F 25.3 lagoon outlet (B)b 16.3 Second series of a Less a blank value of 16.2 pg/L. samples collected from mill B at a later date.
was used to provide an estimated concentration for a,a,a',a'-tetrachlorodimethyl sulfone, for which no pure standard was available for calibration. Precision (percent relative standard deviation) of analysis, established from five replicate analyses of effluent from mill D, was found to be f l % and f8% for a,a-dichlorodimethyl sulfone and a,a,a'-trichlorodimethylsulfone, respectively, Extraction of a 10-mL aliquot of effluent from mill D twice with 10-mL volumes of methyl tert-butyl ether revealed that a single extraction with this solvent quantitatively recovered the chlorinated sulfones except for ala-dichlorodimethyl sulfone, for which the recovery was 90%. The concentrations reported for a,adichlorodimethyl sulfone in Table IV and Figures 2, 3,5, and 6 are not corrected for extraction efficiency. Reference Compounds. The following standards were obtained from commercial suppliers: 2,2,2-trichloroethanol (Aldrich), 1,1,2,3,3-pentachloro-l-propene (Columbia Organic Chemicals), and dimethyl trisulfide (Pfaltz & Bauer). A pure sample of a,a,a'-trichlorodimethylsulfone was prepared according to the method of Truce et al. (49). A sample of a,a-dichlorodimethyl sulfone synthesized by A. B. McKague (B.C. Research, Vancouver, B.C.) was provided by L. LaFleur (NCASI, Corvallis, OR). Biological Testing. Toxicity to juvenile rainbow trout (Salmo guirdneri) was determined by static 96-h bioassays at 10 f 1 "C using iron-free well water (pH 7.4, hardness 280 mg/L as CaCOJ for dilution. The tests were done in 5 L of solution containing five fish, giving a fish loading density of 0.8 L/g. The pH of the test solution was adjusted to 7.0 with dilute HC1 solution and aerated until oxygen saturation. Gentle aeration was used throughout the 96-h test period to maintain the oxygen level. Controls were run concurrently. For testing of the acute toxicity of a,a,a'-trichlorodimethyl sulfone, there was no replacement of the test chemical or monitoring of its concentration during the 96-h test period. Ames mutagenicity testing was performed under contract by B.C. Research, Vancouver, B.C. Results and Discussion Chloroform in Biotreated BKME. As shown in Table 111, the average chloroform concentration for the nine biologically treated BKME samples was 43 pg/L, and the levels ranged from 6.5 to 105 pg/L. The results from this study are very similar to those of Claeys et al. (3),who found an average chloroform level of 24 pg/L and a range of 4-112 pg/L from an investigation of eight bleached kraft biologically treated effluents. To get an indication of the reduction of chloroform across the biobasins, a set of samples corresponding to lagoon influent and lagoon effluent for mill B's biobasin was examined for chloroform. The removal efficiency of 92% found for mill B's aerated lagoon (Table 111)compares well with the 94% value found by NCASI from a study of the biological treatment systems
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Flgure 2. Capillary GC/ECD profiles for chlorinated neutral organics in biotreated BKME from mills A-D: S, Internal standard: 1, unknown; 2, dimethyl trisulfide (number In brackets = concentration in micrograms per liter).
at several bleached pulp mills (3, 32). After dilution of the pulp mill effluents by the recipient waters, chloroform levels are expected to be at the submicrogram per liter level (for typical dilutions of 100 and greater). The effects, if any, of such trace levels of chloroform on the receiving environment are unknown. However, owing to its volatility, chloroform is not expected to be persistent in the aquatic environment. Since 1974 when it was discovered that chloroform and, to a lesser extent, other trihalomethanes are present in certain drinking water supplies (50,51),there has been continued concern about the presence of such compounds in potable water. The trihalomethanes were found to be formed by reaction of the chlorine used for disinfection with organic material present in the drinking water. The initial concern about chloroform in drinking water supplies intensified with the report by the U S . National Cancer Institute in 1976 that chloroform is a suspected carcinogen. Subsequently, in 1978 the U.S. EPA proposed a maximum allowable limit of 100 pg/L for total trihalomethanes in drinking water supplies. As noted by the National Council for Air and Stream Improvement (3),the trace levels of chloroform of pulp mill origin likely to be present in the raw water for downstream water purification plants are expected to be of little consequence relative to the amounts present in the typical finished, C1,-disinfected drinking water or the 100 pg/L limit. Chlorinated Neutral Organic Compounds in Biotreated BKME. An examination of the capillary GC/ ECD chromatograms for chlorinated neutral organics in the nine lagoon outlet samples as shown in Figures 2 and Environ. Sci. Technol., Vol. 17,No. 9, 1983 533
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3 reveals that the general features of the GC/ECD profiles are very similar for all of the biotreated effluents. By far the single most dominant chlorinated neutral organic compound corresponds to a chlorinated sulfone, a,a-dichlorodimethyl sulfone (DDS, compound VI in Figure 1). McKague (27) and Lindstriim et al. (8) had previously identified this compound in spent kraft chlorination liquors. This sulfone was found to be present in all nine samples of lagoon-treated effluent tested, and its concentration ranged from 64 pg/L for mill I to 429 pg/L for mill A. The average DDS concentration found in biologically treated BKME was 223 pg/L. A trichlorinated sulfone, viz., a,a,a'-trichlorodimethylsulfone (TDS), was also detected in the biologically treated effluents but at levels much lower than those found for the dichloro sulfone. The average level of this compound in the biotreated effluents was 6.1 pg/L, and its concentration ranged from 0.3 pg/L for mill I effluent to 12.4 pg/L for effluent from mill B. Preliminary results indicate that a tetrachlorinated sulfone, viz., a,a,oc',d-tetrachlorodimethyl sulfone (TTDS), was also present in the treated effluent exiting from the biobasins of at least three pulp mills (mills B, D, and G) studied. The compound tentatively identified as TTDS was estimated to be present in these effluents at a concentration of -1 pg/L. The identification of DDS and TDS in biologically treated BKME samples was confirmed by comparison with the mass spectrum and GC retention time for pure standards of these compounds. Mass spectra for the diand trichlorinated sulfones are shown in Figure 4. Both mass spectra are dominated by the C1, cluster a t m / e 83, corresponding to the CHC12+fragment ion. Overall these 534
Environ. Sci. Technol., Vol. 17, No. 9, 1983
mass spectra contain little additional information to distinguish the two compounds from one another or to make an identification by mass spectral interpretation. The Cll cluster at m / e 49 (correspondingto the CH2Cl+fragment) and the peak at m / e 79 (corresponding to the CH3S02+ fragment) can be used to confirm the identity of the trichloro sulfone and the dichloro sulfone, respectively. The GC peak that was tentatively identified as a,a,a',a'tetrachlorodimethyl sulfone (TTDS) by GC/MS analysis also gave a mass spectrum very similar to those obtained for the di and trichloro sulfones (given in Figure 4). Synthesis of a pure standard of "TDS is required to obtain a complete identification. A relatively dominant GC/ECD peak that was present in five of the nine effluent extracts (e.g., see peak 2 in Figures 2 and 3) did not, in fact, correspond to a chlorinated compound. This compound has been identified as dimethyl trisulfide by GC/MS analysis. Surprisingly, this compound gave a very strong response to the electron capture detector; for example, the molar response factor for dimethyl trisulfide was found to be about 2.5 times that for tetrachloropropene. The concentration found for dimethyl trisullide in mill G biotreated effluent was 62 pg/L. Keith (52)has previously reported this compound in biologically treated effluent for an unbleached kraft paper mill. Peak 1 in Figures 2 and 3, which was common to eight of the effluent samples, is a compound that has yet to be identified. For a preliminary assessment of the effect of biological treatment on the chlorinated sulfones, new samples of combined bleached kraft mill effluents entering and leaving mill B s aerated lagoon were assayed for chlorinated neutrals. The capillary GC/ECD chromatogramsfor these two samples (see Figure 5) reveal that the chlorinated sulfones passed through this aerated lagoon with little, if any, change in concentration. It is also noteworthy that overall the GC/ECD profiles for the untreated and biotreated BKMEs are very similar. Peak 1in Figure 5 was identified as 2,2,2-trichloroethanol by GC/MS analysis. This identification was confirmed with a pure sample of this compound. The concentration of this chlorinated alcohol in the lagoon outlet sample was found to be 29 wg/L. Because the retention time for this compound is the same as that for 1,3-dichloroacetone, this peak could easily be mistaken for the dichloroacetone where identifications are based solely on retention time. According to retention time data, a small amount (-4 pg/L) of 1,1,2,3,3-pentachloro-l-propene was found in the untreated BKME (see peak 4 in Figure 5). The presence of the pentachloropropenein this (untreated) effluent sample was verified by GC/MS. Pentachloropropenewas not detected
I
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Flgure 5. GC/ECD profiles of chlorinated neutral organlcs through the biological treatment system of bleached kraft pulp mill B: S, internal standard; 1, 2,2,2-trichloroethanol; 2, unknown;3, dimethyl trisulfide; 4, 1,1,2,3,3-pentachloro-l-propene(number in brackets = concentration in micrograms per liter).
Table IV. Summary of Chlorinated Neutral Organics Found from a Survey of Nine Biologically Treated Bleached Kraft Mill Effluents frequency concn, wg/L of compounds detection'" mean range 9 43 7-105 chloroform 9 223 64-429 DDS~ 9 6.1 0.3-12.4 TDSC 3 0.7 0.4-1.1 TTDS~ DDS a Out of a total of 9 mill effluent samples. a,a-dichlorodimethyl sulfone. TDS = a,a,a'-trichlorodiTTDS = a,a,a',a'-tetrachlorodimethyl methyl sulfone. sulfone.
*
in the biologically treated effluent. Table IV provides a summary of the concentrations of chlorinated neutral organics found from this study in biologically treated bleached kraft mill effluents. As discussed previously, most of the chlorinated organics that have been reported to be present in biologically treated BKME (see Table 11)consist mainly of chlorinated acidic compounds, viz., chlorinated dehydroabietic acids and chlorinated phenolics. In order to obtain some perspective of the magnitude of the chlorinated neutral components relative to chlorinated phenolics, which account for a major part of the chlorinated acidic compounds, we extracted one of the biologically treated effluents at lower pH (pH 4) to recover both the phenolic and neutral compounds. Figure 6 gives a comparison of the GC/ECD profiles for a sample of effluent from mill B extracted at pH 4 and 12. The pH 4 chromatogram shows a,a-dichlorodimethyl sulfone (DDS) to be the single most dominant chlorinated organic constituent (neutral or acidic) present in biologically treated bleached kraft mill effluents. From an investigation of eight biologically treated bleached kraft mill effluents, Claeys et al. (3)have reported mean concentrations of 17, 6, and 39 pg/L for 12-chlorodehydroabietic acid, 14-chlorodehydroabietic acid, and 12,14-dichlorodehydroabietic acid, respectively. The results of Figure 6 also show that the alkaline conditions (pH 12) used for solvent extraction of the effluent samples do not affect the analysis of these chlorinated neutral organic compounds. Some of the chlorinated neutral organics present in the effluent could decompose under the alkaline conditions (e.g., chlorinated acetones, if present) and thus go undetected. However, the chromatogram for extraction at pH 4 (see Figure 6) indicates that except for the chlorinated phenolics, very few additional peaks relative to the strongly alkaline extraction (pH 12) were observed. This workup
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Figure 6. Comparison of GC/ECD profiles for blotreated BKME (mill B) extracted under acidic (pH 4) and alkaline (pH 12) conditions: S, internal standard; 1, unknown; 2, dimethyl trisulfide; CP3, 2,4,6-trichlorophenol; CG3, 3,4,5-trichloroguaiacol;CG4, 3,4,5,6-tetrachloroguaiacol (number in brackets = concentration in rnlcrograms per liter).
procedure would tend to isolate those chlorinated organics that are chemically somewhat persistent. Estimation of Environmental Impact. Although over 70 chlorinated neutral organics have been identified in spent kraft bleaching liquors (see Table I), we were able to find only the following four major compounds consistently in biologically treated combined bleached kraft mill effluents: chloroform, a,a-dichlorodimethyl sulfone (DDS), a,a,a'-trichlorodimethyl sulfone (TDS), and a,a,a',a'tetrachlorodimethyl sulfone (TTDS). However, this study does not exclude the possibility that some of the other chlorinated neutral organics (cited in Table I) might also be present in the biologically treated BKME samples. Although the electron capture detector, which was used for the analysis of our effluent extracts, is selective and sensitive for chlorine-containing organic compounds, the sensitivity of this detector declines appreciably for the less highly (particularly mono- and di-) chlorinated organic compounds. For example, the ECD responses (on a weight basis) of tetra-, tri-, and dichlorinated benzenes relative to monochlorobenzene have been found (53)to be approximately 7000, 5000, and 500, respectively. An inspection of the GC/ECD traces in Figure 2 shows that if other more highly chlorinated (i.e., containing three or more chlorine substituents) neutral organics amenable to GC analysis are present in the biotreated BKME samples, the concentrations for such compounds are likely for the most part to be < 1 pg/L. Holmbom and Lehtinen (21) have reported the presence of tetrachloroacetone at a concentration of 40 pg/L in combined bleached kraft mill effluent after biological treatment. It is not clear if these workers had confirmed the presence of this compound in the effluent by GC/MS analysis. In separate experiments, we have observed that tetrachloroacetone in water can be chemically degraded after standing for 1 day at neutral pH and at room temperature. The latter observation suggests that such a compound is not likely to survive the rigorous treatment conditions prevailing in a well-operated aerated lagoon. For an assessment of the risks involved in releasing chemicals to the aquatic environment, information about factors such as the biodegradability, persistence, bioaccumulation tendency, and biological effects of such compounds is required (54). In this study, we have identified di- and trichlorinated dimethyl sulfones (DDS and TDS) to be common conN
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stituents of biologically treated BKME. The inability of an aerated lagoon to remove these compounds (e.g., see Figure 4) indicates that they are resistant to biological degradation and thus likely to be relatively persistent compounds in the pulp mill receiving waters. The octanol-water partition coefficients Wow) for various organic compounds have been found to correlate well with their corresponding bioconcentration factors (Kb) in fish (55-57). Consequently, a determination of a chemical’s octanolwater partition coefficient has been recommended as a rapid, less expensive screening technique (56)to eliminate the need for bioconcentration testing. We have determined the KO,value of TDS to be 7.6. Using McKay’s correlation (57) where Kb = 0.048KOw, we obtained a value of 0.365 for TDS’s bioconcentration factor. On the basis of a scale where the bioconcentration potential for the pesticide p,p’-DDE is 100 (56) the bioconcentration potential for a,a,a’-trichlorodimethyl sulfone is clearly very low (7 X lo4)! For comparison, the bioconcentration potentials for chloroform, 2,4,6-trichlorophenol, 1,2,4-trichlorobenzene, and p,p’-DDT are 1 X 3.7, 5.5, and 58, respectively. The less chlorinated a,a-dichlorodimethyl sulfone (DDS) can be expected to have an even lower bioaccumulation potential than TDS. For example, in a separate experiment, we have found that the recovery of TDS from an aqueous sample by extraction with hexane was -12%, where the recovery of DDS was -2%. Two laboratory biological tests were made on a,a,a’trichlorodimethyl sulfone (TDS) to get some information about possible biological effects for this compound. These tests were for acute toxicity using rainbow trout and mutagenic activity determined by the Ames test (58). TDS was observed to be nontoxic to juvenile rainbow trout for concentrations up to 25 mg/L. Similarly, this compound was found to be nonmutagenic when tested against microbial strains TA 100 and TA 1535 with and without metabolic activation (S9). An aqueous solution of TDS (1.1mg/L) was used for mutagenicity testing. The highest level of TDS tested was 1.1pg/plate (1mL). According to McKague, a,a-dichlorodimethyl sulfone is neither toxic to rainbow trout up to 10 mg/L (27) nor Ames mutagenic (59). In summary, although available evidence suggests the chlorinated sulfones (DDS and TDS) to be persistent chemicals in the environment, other information relating to their bioaccumulation potential, acute fish toxicity, and Ames mutagenicity indicates that these compounds are not likely to be an immediate serious risk to the aquatic environment. Acknowledgments
I am grateful to A. Rapsomatiotis for technical assistance, T. Kovacs for fish bioassay testing, and L. LaFleur (NCASI, Corvallis, OR) for helpful discussions and provision of a reference sample of a,a-dichlorodimethylsulfone. The a,a,a’-trichlorodimethyl sulfone standard was synthesized by A. Quesnel while on a cooperative work term from the University of Waterloo, Waterloo, Ontario. Registry No. VI, 37557-96-3; TDS, 64568-19-0; TTDS, 86013-22-1; dimethyl trisulfide, 3658-80-8; chloroform, 67-66-3.
L i t e r a t u r e Cited (1) Ander, P.; Eriksson, K.-E.; Kolar, M.-C.; Kringstad, K.; Rannug, U.; Ramel, C. Sven. Papperstidn. 1977,80, 454. (2) Eriksson, K.-E.; Kolar, M.-C.; Kringstad, K. Sven. Papperstidn. 1979, 82, 95. (3) Claeys, R. R.; LaFleur, L. E.; Borton, D. L. In “Water Chlorination: Environmental Impact and Health Effects”; Jolley, R. L., Brungs, W. A., Cumming, R. B., Eds.; Ann 536
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Arbor Science: Ann Arbor, MI, 1980; Vol. 3, p 335. (4) Leach, J. M. In “Water Chlorination: Environmental Impact and Health Effects”; Jolley, R. L., Brungs, W. A., Cumming, R. B., Eds.; Ann Arbor Science: Ann Arbor, MI, 1980; Vol. 3, p 325. (5) Lindstrom, K.; Nordin, J. Sven. Papperstidn. 1978,81,55. (6) Stockman, L.; Stramberg, L.; de Sousa, F. Cellul. Chem. Technol. 1980, 14, 517. (7) Kringstad, K. P.; Ljungquist, P. 0.;de Sousa, F.; Stromberg, L. M. Environ. Sci. Technol. 1981, 15, 562. (8) Lindstrom, K.; Nordin, J ; Osterberg, F. In “Advances in the Identification and Analysis of Organic Pollutants in Water”; Keith, L. H., Ed.; Ann Arbor Science: Ann Arbor, MI, 1981; Vol, 2, p 1039. (9) Rogers, I. H.; Keith, L. H. Technical Report 465; Environment Canada, Fisheries and Marine Service, 1974. (10) Rogers, I. H.; Keith, L. H. In “Identification and Analysis of Organic Pollutants in Water”; Keith, L. H., Ed.; Ann Arbor Science: Ann Arbor, MI, 1976; p 625. (11) Leach, J. M.; Thakore, A. N. J.Fish. Res. Board Can. 1975, 32, 1249. (12) Lindstrom, K.; Nordin, J. J. Chromatogr. 1976, 128, 13. (13) Leach, J. M.; Thakore, A. N. CPAR Project Report 245-3; Environmental Protection Service, Environment Canada, Ottawa, 1976. (14) Thakore, A. N.; Oehlschlager, A. C. Can. J. Chem. 1977, 55, 3298. (15) Bacon, G. B.; Silk, P. J. CPAR Project Report 675-1; Environmental Protection Service, Environment Canada, Ottawa, 1978. (16) Mortimer, R. D.; Wong, A. CPAR Project Reports 711-1 and 711-2; Environmental Protection Service, Environment Canada, Ottawa, 1978, 1979. (17) Voss, R. H.; Wearing, J. T.; Wong, A. CPAR Project Report 828-1; Environmental Protection Service, Environment Canada, Ottawa, 1979. (18) Lindstrom, K.; Osterberg, F. Can. J. Chem. 1980,58,815. (19) Voss, R. H.; Wearing, J. T.; Mortimer, R. D.; Kovacs, T.; Wong, A. Pap. Puu 1980,62,809. (20) Holmbom, B. Pap. Puu 1980,62,523. (21) Holmbom, B.; Lehtinen, K.-J.; Pap. Puu 1980, 62, 673. (22) Kachi, S.; Yonese, N.; Yoneda, Y. Pulp Pap. Can. 1980,81, No. 10, 105. (23) Shimada, K. J. Jpn. Wood Res. SOC. 1980, 26, 543. (24) Salkinoja-Salonen, M.; Sundman, V. In “Lignin Biodegradation: Microbiology, Chemistry, and Potential Applications”; Kirk, T. K., Higuchi, T., Chang, H.-M., Eds.; CRC Press: Boca Raton, FL, 1980; Vol. 2, p 179. (25) Voss, R. H.; Wearing, J. T.; Wong, A. In “Advances in the Identification and Analysis of Organic Pollutants in Water”, Keith, L. H., Ed.; AM Arbor Science: Ann Arbor, MI, 1981; Vol. 2, p 1059. (26) Salkinoja-Salonen, M.; Saxelin, M.-L.; Pere, J.; Jaakola, T.; Saarikoski, J.; Hakulinen, R.; Koistinen, 0. In “Advances in the Identification and Analysis of Organic Pollutants in Water”; Keith, L. H., Ed.; Ann Arbor Science: Ann Arbor, MI, 1981; Vol. 2, p 1131. (27) McKague, A. B. Can. J. Fish. Aquat. Sci. 1981, 38, 739. (28) Ota, M.; Durst, W. B.; Dence, C. W. Tappi 1973,56, No. 6, 139. (29) Kanazawa, K.; Hosoya, S.; Nakano, J. Jpn. Tappi 1977,31, No. 7, 45. (30) Shimada, K. Jpn. Tappi 1977, 31, No. 2, 39. (31) Harris, E. E.; Sherrard, E. C.; Mitchell, R. L. J. Chem. SOC. 1934, 56, 889. (32) Claeys, R. R. Technical Bulletin 298; National Council of the Paoer Industrv for Air and Stream Improvement, 1977. (33) Bjorseih, A.; Lunie, G.; Gjos, N. Acta Chem. Scand., Ser. B 1977, 31, 797. (34) Biorseth, A.; Carlberg, - G. E.; Moller, M. Sci. Total Environ. 1979, 11, 197. (35) Douglas, G. R.; Lee, E. G.-H.; McKague, A. B., paper presented a t the CPPA 67th Annual Meeting, Montreal, Canada, 1981. (36) McKague, A. B.; Lee, E. G.-H.; Douglas, G. R. Mutat. Res. 1981, 91, 301.
Environ. Sci. Technol. 1983, 17, 537-542
(37) Holmbom, B. R.; Voss, R. H.; Mortimer, R. D.; Wong, A. (38) (39) (40) (41)
(47) Richard, J. J.; Junk, G. A. J. A W W A 1977, 69, 62. (48) Eklund, G.; Josefsson, B.; Roos, C. J. High Resolut. Chromatogr., Chromatogr. Commun. 1974, 1, 34. (49) Truce, W. E.; Birum, G. H.; McBee, E. T. J. Am. Chem. SOC.1952, 74, 3594. (50) Rook, J. J. Water Treat. Examin. 1974, 23, 234. (51) Bellar, T. A.; Lichtenberg, J. J.; Kroner, R. C. J. AWWA
Tappi 1981,64, No. 3, 172. McKague, A. B.; Rettig, S. J.; Trotter, J.; Douglas, G. R. Can. J. Chem. 1981,59, 3372. Nestmann, E. R.; Lee, G.-H.; Matula, T. I.; Douglas, G. R.; Mueller, J. C. Mutat. Res. 1980, 79, 203. Ellenton, J. A.; Douglas, G. R.; Nestmann, E. R. Can. J. Genet. Cytol. 1981, 23, 17. Rannug, U. In ”Water Chlorination: Environmental Impact and Health Effects”;Jolley, R. L., Brungs, W. A,, Cumming,
R. B., Eds.; Ann Arbor Science: Ann Arbor, MI, 1980; Vol. 3, p 851. (42) Rapson, W. H.; Nazar, M. A.; Butsky, V. V. Bull. Environ. Contam. Toxicol. 1980,24, 590. (43) LaFleur, L. Technical Bulletin 347; National Council of the Paper Industry for Air and Stream Improvement, 1981. (44) Leach, J. M.; Meier, H. P.; Chung, L. T. K.; Mueller, J. C. CPAR Project Report 408-3; Environmental Protection Service, Environment Canada, Ottawa, 1978. (45) Leach, J. M.; Chung, L. T. K. EPA-600/S2-80-206; U.S. EnvironmentalProtection Agency: Washington, DC, 1981. (46) Mieure, J. P. J. A W W A 1977, 69, 60.
1974, 66, 703. (52) Keith, L. H. Environ. Sci. Technol. 1976, 10, 555. (53) Oliver, B. G.; Bothen, K. D. Anal. Chem. 1980,52, 2066. (54) Landner, L. Sven. Papperstidn. 1979, 82, 444. (55) Neely, W. G.; Branson, D. R.; Blau, G. E. Environ. Sci. Technol. 1974, 8, 1113. (56) Veith, G. D.; DeFoe, D. L.; Bergstedt, B. V. J.Fish. Res.
Board Can. 1979, 36, 1040.
(57) McKay, D. Environ. Sci. Technol. 1982, 16, 274. (58) Ames, B. N.; McCann, J.; Yamasaki, E. Mutat. Res. 1975, 31, 347.
(59) McKague, A. B., B. C. Research, Vancouver, B.C., personal communication, 1982. Received for review December 8,1982. Accepted April 12, 1983.
NOTES Estimating Activity Coefficients for Use In Calculating Environmental Parameters William Brian Arbuckle Department of Civil Engineering, The University of Akron, Akron, Ohio 44325
rn A solution-of-groups method is available for calculating activity coefficients (UNIFAC) that requires only a compound’s structure. Activity coefficients can then be used to estimate octanol/water partition coefficients and aqueous solubilities and combined with vapor pressures to estimate Henry’s law constants. The UNIFAC method is outlined and used to estimate a limited number of values for each of the above parameters. Estimates of Henry’s law constants were best, with an average absolute error (difference between the logarithms of predicted and observed values) of 0.112 log units. The octanol/water partition coefficient’s average absolute error was 0.333 log units with a maximum error of 1.0; all but one of the predicted values are greater than the actual values. Solubilities were predicted least accurately (average absolute error of 0.418 log units with a maximum error of 1.9). The greatest errors resulted when predicted C,values were less than 0.1 mol/m3. With specific organic contaminants becoming a concern in our waters and wastes, predicting a compound’s behavior in the environment and in treatment processes becomes important. The octanol/water partition coefficient (K,J is used to predict a compound’s ability to bioaccumulate (1) and its ability to sorb on soils and sediments (2). Henry’s law constants (H)are needed for predicting air/water exchanges (3). A compound’s solubility (C,) is important whenever water/compound contact is likely (3). Limited tabulations of octanol/water partition coefficients (4),solubilities (5,6)and Henry’s law constants (7) are available. If octanol/water partition coefficients, solubilities, and Henry’s law constants are unavailable, 0013-936X/83/0917-0537$01.50/0
they could be calculated from activity coefficients. A method to estimate activity coefficients is available that requires only a knowledge of a chemical’s structure.
UNIFAC The UNIFAC method can be used to calculate activity coefficients from chemical structures. It was introduced in 1975 (8) and was recently extended (9). It is based on the UNIQUAC model for determining activity coefficients for nonideal mixtures (IO). UNIQUAC (universal quasichemical) separates the activity coefficient for each component in a multicomponent mixture into two parts; a combinatorial part that depends on the component’s molecular structure (basically a sum of functional group volumes and areas) and a residual part dependent upon functional group interaction within the entire mixture. The resulting model is In yi = In y? + In yiR (1) where yi = activity coefficient for the ith molecular component in the mixture. The superscripts refer to the combinatorial (c) and residual (R) parts. In UNIQUAC, experimental binary-phase equilibria data are required to determine the yiR. Fredenslund et al. used a solution-of-groups approach to replace the experimental data needs of UNIQUAC (8) and therefore to calculate yiR. Their method is UNIFAC (UNIQUAC functional-group activity coefficient). A solution-of-groups method is based on the fact that while many thousands of chemicals exist and may be of concern, considerably fewer functional groups make up all these compounds (for instance, all the linear alkanes contains
0 1983 American Chemical Society
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