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Are Pulp and Paper Mills Sources of Toxaphene to Lake Superior and Northern Lake Michigan?
J. Great Lakes Res. 25(2):383–394 Internat. Assoc. Great Lakes Res., 1999
Are Pulp and Paper Mills Sources of Toxaphene to Lake Superior and Northern Lake Michigan? Kathryn E. Shanks, Jeffrey G. McDonald, and Ronald A. Hites* School of Public and Environmental Affairs and Department of Chemistry Indiana University Bloomington, Indiana 47405 ABSTRACT. Toxaphene was a broad-spectrum pesticide consisting of a mixture of highly chlorinated bornanes and bornenes. After its ban in 1982, toxaphene concentrations have shown a general decline in the environment as a whole and in most of the Great Lakes specifically. Recent work, however, shows that toxaphene concentrations are not decreasing in fishes from Lake Superior and northern Lake Michigan. Non-atmospheric, relatively localized sources are a possible explanation for these observations. For example, toxaphene could be inadvertently produced and released by pulp and paper mills, which could be synthesizing toxaphene-like compounds as a byproduct of bleached paper production. Reported here is a study of surficial river sediment collected upstream and downstream from seven pulp and paper mills, from five areas of previous toxaphene use, and from two presumed pristine locations. Concentrations of toxaphene found downstream are similar to those found upstream from each of the pulp and paper mills. Concentrations in sediment from rivers near previous toxaphene use locations were higher than concentrations in the background samples. These data suggest that pulp and paper mills are not now sources of toxaphene but that toxaphene used as a pesticide in the Great Lakes basin (although these uses were very small compared to its use in the southern US) could be a potential source. INDEX WORDS: Toxaphene, paper mills, Lake Superior, Lake Michigan, sediment.
INTRODUCTION Toxaphene was a broad-spectrum insecticide consisting of a mixture of bornanes and bornenes substituted with up to 10 chlorines (Hartley and Kidd 1983). The Hercules Company first produced toxaphene in 1947 by the photochlorination of camphene, an isomerization product of α-pinene, which was in turn isolated from softwoods such as conifers (Rapaport and Eisenreich 1988). Commercial toxaphene consisted of approximately 600 congeners (Jansson and Wideqvist 1983), of which less than 30 have been individually isolated and characterized. During the late 1960s and early 1970s, toxaphene was the replacement of choice for DDT, and at that time, toxaphene was the most heavily used insecticide in the United States (Howdeshell and Hites 1996). Toxaphene was primarily used in the southern US as an insecticide for cotton, but its use was eventually broadened to killing insects on livestock 1Corresponding
and to controlling rough fish in lakes (Voldner and Schroeder 1989; Bidleman et al. 1988). Toxaphene was used in the Great Lakes basin and Canada, but this use accounted for < 1% of its total use (Von Rumker et al. 1975). The U.S. Environmental Protection Agency (US EPA) banned toxaphene in 1982, although existing stocks could still be used under certain circumstances until 1986 (Fed. Regist. 1982). As of 1992, most developed countries had banned the use of toxaphene; however, it may still be used in some undeveloped countries (Voldner and Li 1993). Toxaphene is transported through the atmosphere to the Great Lakes, where it contaminates fish. Toxaphene concentrations in both lake trout and smelt from the Great Lakes seem to have responded to the ban in 1982 (Glassmeyer et al. 1997). For example, the toxaphene concentrations in trout from Lake Ontario decreased by about a factor of about 10 between 1982 and 1992. There are, however, two important yet puzzling exceptions: In Lake Superior and in northern Lake Michigan, the levels of toxaphene in trout and smelt have not changed over
author. E-mail: [email protected]
383
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the last 10 to 15 years (Glassmeyer et al. 1997). Why are fish from these two locations not showing the expected decline in toxaphene concentrations such as that observed in the other Great Lakes? There are two hypotheses: (a) The water in Lake Superior and northern Lake Michigan is colder than in the other Great Lakes, resulting in reduced airwater exchange and reduced degradation of toxaphene, and (b) Toxaphene is being supplied to Lake Superior and northern Lake Michigan by nonatmospheric sources. This paper addresses this second hypothesis. There are two non-atmospheric sources that could be delivering toxaphene to the Great Lakes: First, although the use toxaphene in the Midwest was slight, it is possible that farming the soil on which it had once been applied brings contaminated soil to the surface, and this process re-releases toxaphene into the environment. Second, it is possible that toxaphene-like compounds are produced and released by pulp and paper mills, which are numerous in the Great Lakes basin. This second idea requires some chemical elaboration. As mentioned above, toxaphene is produced by the photochlorination of camphene, an isomerization product of α-pinene (Fig. 1). Both camphene and α-pinene are present in the softwood pulp from which paper is made. In fact, a typical pulp and paper mill has a waste stream coming from the pulping process that contains terpenes that could act as potential precursors of toxaphene-like compounds (Kringstad and Lindstrom 1984). In addition, pulp and paper mills are intensive users of chlorine-based bleaching agents. On average, pulp and paper mills use 60 to 70 kg of chlorine per metric ton of pulp. The chemical forms of chlorine depend on the mill and bleaching process but include Cl 2 , ClO 2 , and ClO 4– (Kringstad and Lindstrom 1984). Thus, pulp and paper mills have all the nec-
FIG. 1.
Commercial synthesis of toxaphene.
essary ingredients for the inadvertent production of toxaphene-like compounds. If produced, these chlorinated by-products could be discharged into the mill’s receiving stream and eventually make their way to the Great Lakes. There is some literature to support the inadvertent production of toxaphene from the bleaching of paper. A study by Jarnuzi et al. (1992) found 90 ng/L and 80 ng/g of “toxaphene-like” compounds in water effluent and striped mullet fish, respectively, that had been collected near pulp and paper mills. In that study, the pentachlorinated homologue was the most predominant. Laboratory studies have also verified that camphene can be chlorinated under conditions ranging from complete darkness to simulated and real sunlight and at pHs of 2 and 8. At pH 2, the toxaphene-like products had chlorination levels which ranged from 2 to 5 in the dark and 2 to 9 under lighted conditions, depending on the time allowed for the reaction to take place (Larson and Marley 1986). At pH 8, small amounts of mono- and dichlorinated toxaphene-like products were formed under both dark and lighted conditions. To determine if these laboratory results can be extrapolated to the natural environment and to determine if pulp and paper mills are potential sources of toxaphene-like compounds to the Great Lakes, toxaphene was measured in sediment collected upstream and downstream from the discharge points of seven pulp and paper mills, most of which now use chlorine dioxide in their bleaching processes (J. Schwartz, American Forst and Paper Association, personal communication, 1998). If the mills were discharging toxaphene, relatively elevated concentrations downstream from the mills should be observed. As controls, toxaphene was also measured near locations where it may have been used for agricultural purposes and at pristine locations
Are Paper Mills Sources of Toxaphene? TABLE 1.
385
Sample locations and descriptions.
Site Rainy River Menominee River Escanaba River Peshtigo River Wisconsin River Wisconsin River
Abbr.a RA ME ES PE WI WI
Fish Lake Mississippi River
FL MN
Saginaw River SA Sheboygan River SH Root River R Grand River G Sand Lake SN aSee Figure 2 for locations bOperated by Georgia-Pacific Corp.
Location International Falls, MN Quinnesec, MI Escanaba, MI Peshtigo, WI Port Edwards, WI Nekoosa, WI
Mill Boise Cascade Champion Paper Mead Paper Badger Paper Consolidated Paper Port Edwards and Nekoosa Paperb
Type Pulp and paper Pulp and paper Pulp and paper Pulp and paper Pulp and paper Pulp and paper
Stark, MN Bemidji, MN
Background Background
Saginaw, MI Sheboygan Falls, WI Racine, WI Grand Haven, MI Scandia, MN
Previous toxaphene use Previous toxaphene use Previous toxaphene use Previous toxaphene use Previous toxaphene use
where toxaphene should only have been delivered by the atmosphere. EXPERIMENTAL METHODS Sampling Sediment samples were collected in March and July of 1997 in conjunction with the US EPA; one of the authors (KES) was present at both times. The locations of the sampling sites are listed in Table 1 and shown in Figure 2. For the pulp and paper mill sites, six samples (in close proximity to one another) were collected above and below each mill. The Wisconsin River site was sampled at three locations because there were three mills discharging their effluent into the same river. The lower two mills shared a common effluent discharge source. Samples were taken between the two discharge points as well as above and below them. The sediment collected from all sites was divided and splits were given to the mill from where the sample was obtained. Distances from the mills to where the samples were collected were all less than 0.4 km. Sediments (three replicates in close proximity to one another) were also collected from rivers that drain areas where the US EPA indicated that toxaphene had been used as a pesticide. Sand Lake, a known toxaphene use location, was sampled once to obtain a deep piston core, which was sub-divided into 13 sub-samples. Background samples (also
three replicates) were collected from pristine lakes and rivers that were assumed to be free of any input of toxaphene other than from atmospheric deposition. Samples were collected using three different methods depending on location, accessibility, and the nature of the sediment. In March 1997, the cores were collected with a 5 cm diameter gravity corer (hand-built by the Minnesota Pollution Control Agency staff). In July 1997, the cores were collected with a 5 cm diameter commercial sediment corer (WildCo Wildlife Supply, Saginaw, MI). When sediment conditions would not allow the use
FIG. 2. Map of sampling sites; sampling site codes reported in Table 1.
386
Shanks et al.
of corers on the July sampling trip, sediment was collected with an Eckman dredge sampler (WildCo Wildlife Supply). Samples were collected by wading or from a boat or bridge depending on the accessibility of the site. Sediment from core tubes was extruded, and the top 5 to 10 cm was retained for analysis. Samples from the dredge sampler were directly transferred into collection jars. A single 65cm deep sediment core was collected from Sand Lake. This core was sectioned every 5 cm. After being filled, the sample jars were placed in coolers with ice, shipped back to the laboratory, and stored at 4°C until they were warmed to room temperature for extraction.
toxaphene peaks. This file was imported into a QBasic program, which selected toxaphene peaks using chlorine isotope ratios and corrected for carbon-13 and other interferences.
Extraction and Analysis Sample preparation, extraction, clean up, and other details have been described elsewhere (Howdeshell and Hites 1996). The one exception to this published method was the use of 13Cl1-chlordane (Cambridge Isotope Laboratories, Cambridge, MA) as the internal standard. Toxaphene was quantitated by gas chromatographic mass spectrometry (Hewlett Packard 5989A or 5973) operated in the electron capture, negative ionization mode. The instruments were equipped with 30 m, DB-5MS columns (internal diameter, 250 µm; film thickness, 0.25 µm; J&W Scientific, Folsom, CA). The injection port was operated in the splitless mode at 285°C with a 1.9 min. vent time. Helium was the carrier gas at a velocity of 25 cm/s, and the injection volume was 1 µL. The temperature program began at 40°C for 1 min; the temperature was then ramped at 10°C/min to 200°C, at 1.5°C/min to 230°C, and at 10°C/min to a final temperature of 300°C, where it was held for 5 minutes. The transfer line connecting the GC to the MS was at 300°C, and the ion source was at 125°C. The reagent gas was methane at a pressure of 0.43 Torr as measured in the ion source by a direct insertion probe in the 5989A instrument. Data were acquired using the selected ion monitoring method based on ions suggested by Swackhamer et al. (1987). A relative response factor standard of Hercules toxaphene was run every 5 samples. Quantitation used a software system recently described by Glassmeyer et al. (1999). Briefly, peaks in the background-subtracted chromatogram were integrated using Hewlett Packard’s EnviroQuant program. These data were then imported into a macro (written in-house), which generated a file of retention times and areas of potential
RESULTS AND DISCUSSION The results of this study are presented in Table 2 and summarized in Table 3. While there were considerable variations within the six (or three) replicates, only an arithmetic average and standard error of the non-zero concentrations are reported in Table 3. Using these average statistics and paired Student’s t-tests, it was found that the concentrations of toxaphene in sediments downstream from each mill’s effluent discharge point are not significantly different (at the 90% confidence level) from those upstream. On average, the concentrations of toxaphene in sediments upstream from the mills ranged from 1.4 to 8.3 ng/g, and downstream from the mills, the concentrations ranged from 1.5 to 8.7 ng/g. From these data, it can be concluded that these pulp and paper mills are probably not now sources of toxaphene to the Great Lakes. With the exception of the Sand Lake site, the average concentration of toxaphene in the sediment samples collected from rivers that drain previous toxaphene use areas ranged from 6.0 to 43 ng/g. These concentrations were somewhat higher than those in the samples collected near the pulp and paper mills. The average toxaphene concentrations at the two background sites were 0.3 and 0.5 ng/g, values much lower than those observed at all of the other sites. The samples from Sand Lake were in the form of a chronologically segmented core. In this case, the six upper sections had higher toxaphene concentrations (0.2 to 3.6 ng/g) as compared to the lower sections (not detected to 1.0 ng/g). The upper sections are comparable to the previous toxaphene use samples, and the lower sections are comparable to the background sites. The elevated concentrations in previous use areas compared to the background sites suggests that some of
Loss-on-ignition LOI was determined for all samples. Sediment samples were weighed, placed in crucibles, and dried at 105°C for 24 hours to remove water. Samples were then re-weighed and heated in a muffle furnace at 525°C for 24 hours and weighed again. Total organic carbon was estimated by dividing the LOI by 1.724 (Howard and Howard 1990).
Are Paper Mills Sources of Toxaphene?
387
TABLE 2. Summary of locations sampled, toxaphene concentrations per homologue, total toxaphene per dry weight of sediment, loss-on-ignition (LOI), total organic carbon (TOC), and total toxaphene per gram organic carbon. In this table “n” means not detected at a limit of detection of about 0.05 ng/g dry sediment per homologue. Rounding of the data to one decimal place may cause slight apparent errors in addition.
GPS Coordinates Code Lat./Lon. Rainy River, Upstream RA 1-1 48 35 38.8N/93 09 27.6W RA 1-2 48 35 37.1N/93 09 25.2W RA 1-3 48 35 38.4N/93 09 24.2W RA 1-4 48 35 37.1N/93 09 25.2W RA 1-5 48 35 36.5N/93 09 19.5W RA 1-6 48 35 38.8N/93 07 19.3W Average Std err Rainy River, Downstream RA 2-1 48 50 30.0N/94 41 44.8W RA 2-2 48 50 31.0N/94 41 38.8W RA 2-3 48 50 33.3N/94 41 41.6W RA 2-4 48 50 30.2N/94 41 38.6W RA 2-5 48 50 33.3N/94 41 38.6W RA 2-6 48 50 33.4N/94 41 35.1W Average Std err Menomenee River, Upstream ME 1-1 45 46 00.8N/87 58 25.5W ME 1-2 45 46 06.4N/87 58 57.7W ME 1-3 45 46 00.3N/87 58 35.9W ME 1-4 45 45 59.0N/87 58 20.5W ME 1-5 45 45 54.2N/87 58 04.9W ME 1-6 45 45 50.5N/87 58 04.9W Average Std err Menomenee River, Downstream ME 2-1 45 45 33.5N/87 54 26.7W ME 2-2 45 45 30.9N/87 54 33.5W ME 2-3 45 45 26.0N/87 54 36.0W ME 2-4 45 45 25.3N/87 54 49.4W ME 2-5 45 45 30.1N/87 54 53.7W ME 2-6 45 45 28.5N/87 55 12.3W Average Std err Escanaba River, Upstream ES 1-1 45 50 24.0N/87 05 28.7W ES 1-2 45 50 24.6N/87 05 28.3W ES 1-3 45 50 25.3N/87 05 27.3W ES 1-4 45 50 27.1N/87 05 26.9W ES 1-5 45 50 28.7N/87 05 26.4W ES 1-6 45 50 26.7N/87 05 17.6W Average Std err
Date Collected
Toxaphene (ng/g dry sed.) Toxaphene by homologue ng/g dry LOI 6 7 8 9 10 sed %
Toxaphene ng/g TOC Organic % Carbon
Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97
0.1 n 0.1 0.1 n 0.1 0.1 0.02
0.5 n 1.3 3.5 0.5 0.6 1.3 0.6
n n 0.2 n n 0.2 0.1 0.06
0.1 n 0.1 n 0.2 n 0.2 n 0.1 n 0.2 0.4 0.1 0.2 0.02
0.7 0.1 1.8 3.7 0.6 1.4 1.4 0.5
15.4 6.8 16.0 38.9 10.8 16.5 17.4 4.6
9.1 4.0 9.4 22.9 6.4 9.7 10.2 2.7
8 2 19 16 9 15 11 3
Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97
n 2.6 0.2 0.2 0.1 0.1 0.7 0.5
0.1 1.0 0.8 0.8 0.3 0.4 0.6 0.1
0.3 0.1 n n 0.1 n 0.2 0.1
n 0.8 0.2 0.1 n 0.4 0.4 0.2
n 0.1 n n n n 0.1
0.4 4.6 1.2 1.2 0.5 1.0 1.5 0.6
18.9 6.0 5.9 4.3 4.5 5.1 7.5 2.3
11.1 3.5 3.5 2.6 2.6 3.0 4.4 1.4
4 131 35 46 18 32 44 18
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
n n 14.9 n n n 14.9
0.7 2.7 7.0 n n 0.2 2.7 1.5
n 0.1 1.2 0.1 n 6.0 n 0.6 0.2 n n 10.0 0.7 3.4 0.5 2.0
n n 1.3 n 0.1 n 0.7 0.6
0.8 4.0 29.2 0.6 0.3 10.2 7.5 4.6
2.5 2.2 4.1 7.9 1.0 2.2 3.3 1.0
1.5 1.3 2.4 4.6 0.6 1.3 1.9 0.6
55 301 1201 13 57 804 405 200
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
n n n 0.1 n n 0.1
0.6 6.5 5.0 2.2 n 7.8 4.4 1.3
n 0.6 1.3 13.1 n 4.1 n 0.1 0.6 0.4 n 3.1 0.9 3.6 0.4 2.0
n 1.7 1.9 n n 3.1 2.3 0.4
1.2 22.7 11.0 2.4 1.0 14.0 8.7 3.6
3.9 7.7 6.3 3.8 5.2 6.0 5.5 0.6
2.3 4.5 3.7 2.2 3.0 3.5 3.2 0.4
51 502 298 111 32 399 232 80
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
n n n n 0.1 n 0.1
n 1.5 n 2.9 40.3 0.3 11.2 9.7
n 0.2 n 0.1 n 0.6 0.3 0.1
n 1.8 n 3.7 41.1 3.1 8.3 6.6
68.2 76.1 9.8 50.7 3.9 6.9 36.0 13.4
40.1 44.8 5.8 29.8 2.3 4.1 21.2 7.9
n 4 n 12 1768 76 465 434 (Continued)
n n n n n n
n 0.2 n 0.7 0.6 2.3 0.9 0.5
388 TABLE 2.
Shanks et al. Continued
GPS Coordinates Code Lat./Lon. Escanaba River, Downstream ES 2-1 45 48 23.3N/87 05 52.3W ES 2-2 45 48 25.8N/87 05 55.7W ES 2-3 45 48 39.3N/87 05 59.2W ES 2-4 45 48 39.8N/87 06 00.8W ES 2-5 45 48 41.7N/87 06 01.8W ES 2-6 45 48 27.1N/87 05 56.9W Average Std err Peshtigo River, Upstream PE 1-1 45 03 35.3N/87 44 48.1W PE 1-2 45 03 58.1N/87 44 40.6W PE 1-3 45 04 03.5N/87 44 38.9W PE 1-4 45 04 10.7N/87 44 35.4W PE 1-5 45 04 24.9N/87 44 39.5W PE 1-6 45 03 36.3N/87 44 52.5W Averagee Std err Peshtigo River, Downstream PE 2-1 45 02 46.7N/87 44 42.6W PE 2-2 45 02 44.3N/87 44 39.6W PE 2-3 45 02 40.2N/87 44 39.1W PE 2-4 45 02 34.8N/87 44 37.4W PE 2-5 45 02 28.3N/87 44 35.7W PE 2-6 45 02 25.4N/87 44 34.6W Average Std err Wisconsin River, Upstream WI 1-1 44 26 44.2N/89 43 26.0W WI 1-2 44 26 55.4N/89 43 04.5W WI 1-3 44 26 59.3N/89 42 20.0W WI 1-4 44 27 06.4N/89 41 14.8W WI 1-5 44 27 12.8N/89 41 15.5W WI 1-6 44 27 09.4N/89 41 49.5W Average Std err Wisconsin River, Middle WI M-1 44 22 27.1N/89 51 01.1W WI M-2 44 22 27.2N/89 51 04.9W WI M-3 44 22 39.9N/89 50 45.3W WI M-4 44 22 41.3N/89 50 42.4W WI M-5 44 23 03.9N/89 50 09.2W WI M-6 44 23 04.4N/89 50 09.8W Average Std err
Date Collected
Toxaphene (ng/g dry sed.) Toxaphene by homologue ng/g dry LOI 6 7 8 9 10 sed %
Toxaphene ng/g TOC Organic % Carbon
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
0.2 n n 31.0 n 0.1 10.4 10.3
0.4 n 0.9 0.1 0.2 n 0.4 0.2
n n 0.1 0.2 0.4 n 0.2 0.1
0.2 0.6 0.1 0.2 1.2 2.1 0.7 0.3
0.1 n n n n 0.1 0.1
0.9 0.6 1.1 31.4 1.7 2.3 6.3 5.0
0.8 0.9 4.0 21.9 5.5 1.7 5.8 3.3
0.5 0.5 2.3 12.9 3.3 1.0 3.4 1.9
189 106 45 244 54 227 144 36
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
n n n n n n
1.0 3.0 1.6 n 0.3 2.6 1.7 0.5
n n n n n 0.5 0.5
0.1 n 0.1 1.0 0.7 0.1 0.4 0.2
n n n n 0.2 0.1 0.2 0.1
1.0 3.0 1.6 1.0 1.4 3.2 1.9 0.4
4.9 0.8 3.1 1.2 10.1 7.8 4.6 1.5
2.9 0.5 1.8 0.7 5.9 4.6 2.7 0.9
36 663 90 139 22 71 170 100
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
n n 8.1 n 0.3 n 4.2 3.9
0.1 0.9 7.2 n 0.6 0.8 1.9 1.3
n 0.3 0.3 n n n 0.3
n 0.1 3.4 2.0 0.4 0.1 1.2 0.6
n n 0.9 1.8 n n 1.3 0.4
0.1 1.3 19.8 3.7 1.4 0.9 4.6 3.1
3.2 2.1 3.4 0.4 0.9 1.2 1.9 0.5
1.9 1.2 2.0 0.3 0.5 0.7 1.1 0.3
4 108 997 1453 262 133 493 241
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
n n n n n n n
0.5 1.0 n n 0.3 n 0.6 0.2
0.3 0.6 n 0.3 n n 0.4 0.1
0.1 0.3 0.3 1.1 n 4.9 1.3 0.9
0.1 0.1 n n n 2.4 0.8 0.8
1.0 2.0 0.4 1.4 0.3 7.3 2.0 1.1
3.6 3.6 2.2 0.7 1.1 0.5 1.9 0.6
2.1 2.1 1.3 0.4 0.6 0.3 1.1 0.3
46 95 28 329 42 2411 491 387
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
n 0.4 n 10.4 n n 0.3 2.4 0.8 0.9 0.1 0.7 0.4 3.0 0.2 1.9
0.1 0.1 0.6 0.2 0.3 1.6 n 0.8 0.2 1.4 1.6 18.2 0.5 3.7 0.3 2.9
0.1 n 0.4 0.2 1.3 10.6 2.5 2.0
0.7 11.2 2.3 3.7 4.6 31.3 9.0 4.7
2.6 10.4 6.3 2.6 8.2 10.1 6.7 1.4
1.5 6.1 3.7 1.5 4.8 6.0 3.9 0.8
45 181 61 243 96 525 192 73 (Continued)
Are Paper Mills Sources of Toxaphene? TABLE 2.
389
Continued
GPS Coordinates Code Lat./Lon. Wisconsin River, Downstream WI 2-1 44 18 24.1N/89 53 51.4W WI 2-2 44 18 20.7N/89 53 40.6W WI 2-3 44 18 12.3N/89 53 36.4W WI 2-4 44 18 05.6N/89 53 33.3W WI 2-5 44 17 59.1N/89 53 29.9W WI 2-6 44 17 48.0N/89 53 31.3W Average Std err
Date Collected Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
Grand River, Previous use G1 43 02 41.1N/86 09 39.9W G2 43 03 09.6N/86 09 52.3W G3 43 03 26.7N/86 10 33.1W Average Std err Root River, Previous use R1 42 43 44.7N/87 47 36.1W R2 42 43 47.1N/87 47 23.5W R3 42 44 00.4N/87 46 45.4W Average Std err Saginaw River, Previous use SA 1 43 29 21.2N/83 54 29.4W SA 2 43 30 06.5N/83 53 37.8W SA 3 43 31 47.9N/83 52 56.1W Average Std err Sheboygan River, Previous use SH 1 43 43 53.2N/87 48 46.7W SH 2 43 43 44.7N/87 48 51.8W SH 3 43 43 39.6N/87 48 59.0W Average Std err
Toxaphene ng/g TOC Organic % Carbon
n n 0.3 n 0.7 n 0.5 0.2
n 0.9 n n 2.2 n 1.6 0.6
n 5.3 n n 0.2 n 2.7 2.6
0.4 5.0 0.9 n 4.4 9.7 4.1 1.7
n 0.3 n n 2.6 3.4 2.1 0.9
0.4 11.6 1.2 n 10.1 13.1 7.3 2.7
1.4 0.7 0.7 1.2 2.6 0.3 1.2 0.3
0.8 0.4 0.4 0.7 1.5 0.2 0.7 0.2
50 2852 278 n 658 6504 2069 1216
n n n
0.1 n 0.1 0.1
0.3 n n 0.3
0.1 n n
n n n
0.5 n 0.1 0.3 0.2
27.2 27.1 27.0 27.1 0.1
16.0 16.0 15.9 16.0 0.1
3 n 1 2 1
Mar-97 Mar-97 Mar-97
n 0.1 0.1 0.1 0.0
n 0.2 0.4 0.3 0.1
n n 0.1 0.1
n n 0.1 0.1
n n n
n 0.3 0.7 0.5 0.2
17.5 18.8 15.8 17.4 0.9
10.3 11.1 9.3 10.2 0.5
n 2 8 5 2
Mar-97 Mar-97 Mar-97
1.3 n 0.7 1.0 0.3
6.9 1.4 2.7 3.7 1.7
1.6 n 1.8 1.7 0.1
1.3 n 0.2 0.7 0.5
0.2 n n 0.2
11.2 1.5 5.4 6.0 2.8
2.0 2.5 2.6 2.4 0.2
1.2 1.5 1.6 1.4 0.1
940 99 346 461 249
Jul-97 Jul-97 Jul-97
0.3 20.9 1.1 7.4 6.7
31.0 34.8 24.9 30.2 2.9
3.4 0.7 4.6 2.9 1.2
0.2 1.0 2.2 1.1 0.6
0.61 0.5 1.7 0.9 0.4
35.4 57.9 34.6 42.6 7.6
2.7 3.6 9.2 5.2 2.0
1.6 2.1 5.4 3.1 1.2
2213 2717 635 1855 627
Jul-97 Jul-97 Jul-97
n n n
10.8 2.4 19.6 10.9 5.0
0.2 n 3.3 1.7 1.6
2.8 0.1 1.0 1.3 0.8
0.4 n 0.2 0.3 0.1
14.1 2.5 24.2 13.6 6.3
15.5 1.4 3.0 6.7 4.5
9.1 0.8 1.8 3.9 2.6
155 300 1348 601 376
Jul-97 Jul-97 Jul-97
n 0.5 n 0.5
15.7 31.8 n 23.8 8.0
n 0.8 n 0.8
0.1 0.6 7.7 2.8 2.5
n n 1.2 1.2
15.9 33.7 9.0 19.5 7.4
11.3 1.2 4.2 5.5 3.0
6.6 0.7 2.5 3.3 1.8
239 4872 365 1826 1524 (Continued)
Mississippi River, Background MN 1 information MN 2 not MN 3 available Average Std err Fish Lake, Background FL 1 45 34 38.8N/93 01 30.8W FL 2 45 34 35.6N/93 01 31.1W FL 3 45 34 37.2N/93 01 27.6W Average Std err
Toxaphene (ng/g dry sed.) Toxaphene by homologue ng/g dry LOI 6 7 8 9 10 sed %
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TABLE 2.
Continued
GPS Coordinates Code Lat./Lon. Sand Lake, Previous use SN 1 45 13 46.3N/92 48 14.8W SN 2 45 13 46.3N/92 48 14.8W SN 3 45 13 46.3N/92 48 14.8W SN 4 45 13 46.3N/92 48 14.8W SN 5 45 13 46.3N/92 48 14.8W SN 6 45 13 46.3N/92 48 14.8W SN 7 45 13 46.3N/92 48 14.8W SN 8 45 13 46.3N/92 48 14.8W SN 9 45 13 46.3N/92 48 14.8W SN 10 45 13 46.3N/92 48 14.8W SN 11 45 13 46.3N/92 48 14.8W SN 12 45 13 46.3N/92 48 14.8W SN 13 45 13 46.3N/92 48 14.8W Average Std err
TABLE 3.
Date Collected Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97
Toxaphene (ng/g dry sed.) Toxaphene by homologue ng/g dry LOI 6 7 8 9 10 sed % 0.1 0.1 0.8 0.2 0.1 0.1 0.1 n n 0.1 n n n 0.2 0.1
0.1 1.4 2.8 1.2 1.6 0.6 0.2 0.1 0.1 0.5 n 0.2 n 0.8 0.3
n 0.2 n n 0.2 0.6 n n n n n n n 0.3 0.1
n n n n n 0.1 0.1 0.1 n n n n 1.0 0.3 0.2
n n n n n n n n n n n n n
0.2 1.8 3.6 1.5 2.0 1.3 0.4 0.2 0.1 0.5 n 0.2 1.0 1.1 0.3
23.2 16.7 15.2 15.4 16.2 18.3 20.9 21.0 19.9 31.6 25.7 25.5 7.7 19.8 1.7
Toxaphene ng/g TOC Organic % Carbon 13.7 9.8 8.9 9.1 9.5 10.8 12.3 12.4 11.7 18.6 15.1 15.0 4.5 11.6 1.0
1 18 40 16 21 12 3 2 1 3 n 1 22 11 3
Summary of toxaphene concentrations and standard errors.
Mill Boise Cascade
Abbr. RA
Champion Paper
ME
Mead Paper
ES
Badger Paper
PE
Consolidated Paper Port Edwards and Nekoosa Paper
WI WI WI
Location Upstream Downstream Upstream Downstream Upstream Downstream Upstream Downstream Upstream Middle Downstream
these areas could be potential sources of toxaphene to the environment, where it could make its way into the Great Lakes. However, it is not possible to estimate how much toxaphene this process might be contributing to Lake Superior or to northern Lake Michigan. These measurements of toxaphene in sediment are compared to some previously reported measurements in Table 4. The previously reported toxaphene concentrations in Lakes Ontario, Michi-
Toxaphene ng/g dry sediment 1.4 ± 0.5 1.5 ± 0.6 7.5 ± 4.6 8.7 ± 3.6 8.3 ± 6.6 6.3 ± 5.0 1.9 ± 0.4 4.6 ± 3.1 2.0 ± 1.1 9.0 ± 4.7 7.3 ± 2.7
Toxaphene ng/g organic carbon 11 ± 3 44 ± 18 410 ± 200 230 ± 80 460 ± 430 140 ± 36 170 ± 100 490 ± 240 490 ± 390 190 ± 70 2,100 ± 1,200
gan, and Superior sediments range from 3 to 45 ng/g, values which are similar to the concentrations reported here for sediment in rivers near pulp and paper mills and near sites of previous toxaphene use, which range from 1.4 to 43 ng/g. Previously reported toxaphene concentrations at other background locations range from 0.6 to 9 ng/g, values which are somewhat higher than the 0.3 and 0.5 ng/g obtained at the background locations of this study. Averaging the samples from Sand Lake over
Are Paper Mills Sources of Toxaphene? TABLE 4. Toxaphene concentrations in selected sediments. Site Rivers near pulp and paper mills Rivers near previous usage sites
Conc. (ng/g dry wgt.) 1.4–9.0 6.0–43
Lake Ontariob Lake Ontarioc Lake Michiganb Lake Superiora Lake Superiorb
15 10–20 15–45 3–15 15
Sand Lake Siskiwit Lakea Outer Islanda Apostle Islandsb Lake Nipigond Mississippi River Fish Lake aPearson et al. (1997) bSwackhamer et al. (1996) cHowdeshell and Hites(1996) dStern and Muir (unpublished data)
1 9 4 4–9 0.6–3 0.3 0.5
the entire core gave a toxaphene concentration of 1 ng/g, a value comparable with other background locations. Because hydrophobic organic contaminants such as toxaphene preferentially associate with organic matter in sediments, the data were also normalized to organic carbon (last column of Table 2). The upstream and downstream averages are also summarized in Table 3. Like the dry weight normalized data, these organic carbon normalized data did not show significantly higher toxaphene concentrations downstream from the pulp and paper mills either. These comparisons support the conclusion that pulp and paper mills are probably not now sources of toxaphene to Lake Superior or to northern Lake Michigan. Rappe et al. (1998) analyzed the sample splits that were provided to the Georgia Pacific Co., and in most cases, these authors found less than about 0.2 ng/g dry weight of total toxaphene. These values seem unusually low, being about 1 to 5% of the concentrations reported here in the same samples. The difference in these results between the two laboratories may indicate a possible bias inherent in one or both of the toxaphene analytical methods. It should be pointed out that all of the data in Table 4 were obtained with the Swackhamer et al. (1987) method while the Rappe et al. (1998) data were ob-
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tained with another method. It is possible that the differences between the two data sets for the Georgia Pacific samples are due to differences in the two methods. It is important to note, however, that neither laboratory finds significant differences in toxaphene concentrations in sediment samples collected from upstream and downstream of pulp and paper mills. The homologue profiles for toxaphene from river sediments near the five pulp and paper mill locations are shown in Figure 3. With the exception of the Wisconsin River, the homologue profiles are not consistent between the upstream and downstream samples near each mill and are not consistent with the commercial mixture of Hercules toxaphene. The homologue profiles for the three samples from the Wisconsin River are consistent with one another, but they differ from the commercial mixture. Most of the homologue profiles for the toxaphene previous use areas and for the background locations (Fig.3) show that the hepta-chlorinated homologue is the most abundant homologue in these samples. Unfortunately the high variability of these homologue profiles prevents drawing firm conclusions about the source of toxaphene in these samples. Miskimmin et al. (1995) have observed that two specific hexa- and heptachlorinated toxaphene homologues (called “hex-sed” and “hep-sed”) are dominant in sediment samples from previous use locations. These authors attribute the presence of these homologues to anaerobic microbial reductive dechlorination of technical toxaphene. Initially, it was thought that these congeners might be present in the samples from the previous use areas as well. However, comparisons of the gas chromatographic retention times of the hexa- and heptachlorinated toxaphene congeners in the samples with those containing “hex-sed” and “hep-sed” showed that these two congeners were not significant components of the samples. Gary Stern, a co-author of the Miskimmin et al. (1995) study, also analyzed our previous use sediment extracts and did not see “hep-sed” or “hex-sed” present in any of the samples. There is considerable variability in the toxaphene concentrations, in the losses-on-ignition (LOI), and in the homologue profiles among the replicate samples taken at the same locations because of problems associated with sampling sediment in rivers. Sediment in rivers can vary dramatically over small spatial regions. For example, at one location, the sediment collected for this study ranged from rich organic sediment to sand to coarse gravel. In addition, the location of sediment deposition zones in a
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FIG. 3. Toxaphene homologue profiles from sediments collected near pulp and paper mills, from previous toxaphene use locations, and from background locations and Hercules toxaphene.
Are Paper Mills Sources of Toxaphene? river can shift because of day-to-day and seasonal flow variations, because of the presence of ice, and because of human influences (such as damming of the rivers and motor boat use). Sediment focusing and defocusing in rivers may also be a major problem, and historic information on the presence of toxaphene could be lost if sediment defocusing were significant. Despite these problems, the sediment samples from these rivers analyzed in this study were sufficiently high in organic carbon to retain toxaphene. We reach this conclusion for two reasons: First, the toxaphene concentrations measured in these river sediments are similar to those measured in lakes, particularly the Great Lakes. Second, the LOI values, and by extension the total organic carbon values, are typical of those for sediments known to accumulate pollutants (Simcik et al. 1996, Baker et al. 1991, Wong et al. 1995). Although these results do not indict the pulp and paper industry as a current toxaphene source, it should be pointed out that things may have been different in the past, and they may be different in the future. Additional toxaphene measurements of mills’ effluent streams and of their various paper products would be helpful. ACKNOWLEDGMENTS We thank David DeVault, Harold Wiegner, Patricia King, Lawrence Lins, and Paul Novak, Jr. for their assistance in sampling. Special thanks go to Sharon Kendall for technical assistance and to Gary Stern for providing the “hex-sed” and “hep-sed” secondary standard. We thank the U.S. Environmental Protection Agency for funding (Grant X985360). REFERENCES Baker, J. E., Eisenreich, S. J, and Eadie, B. J. 1991. Sediment trap fluxes and benthic recycling of organic carbon, polycyclic aromatic hydrocarbons, and polychlorobiphenyl congeners in Lake Superior. Environ. Sci. Technol. 25:500–509. Bidleman, T. F., Zaranski, M. T., and Walla, M. D. 1988. In Toxic Contamination in Large Lakes Vol 1. Schmidtke, N. W., Ed., pp. 257–284. Chelsea, MI: Lewis Publishers. Fed. Regist. 1982. 47:53784. Glassmeyer, S. T., De Vault, D. S., Myers, T. R., and Hites, R. A. 1997. Toxaphene in Great Lakes fish: A temporal, spatial, and trophic study. Environ. Sci. Technol. 31:84–88.
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———, Shanks, K. E., and Hites, R. A. 1999. Automated toxaphene quantitation method. Anal. Chem. 71: 1448–1453. Hartley, D., and Kidd, H., Eds. 1983. The Agrochemicals Handbook. Nottingham, England: The Royale Society of Chemistry. Howard, P. J. A., and Howard, D. M. 1990. Use of organic carbon and loss-on-ignition to estimate soil organic matter in different soil types and horizons. Biol. Fertil. Soils. 9:306–310. Howdeshell, M. J., and Hites, R. A. 1996. Historical input and degradation of toxaphene in Lake Ontario sediment. Environ. Sci. Technol. 30:220–224. Jansson, B., and Wideqvist, U. 1983. Analysis of toxaphene (PCC) and chlordane in biological samples by NCI mass spectrometry. Int. J. Environ. Anal. Chem. 13:309–321. Jarnuzi, G., Matsuda, M., and Wakimoto, T. 1992. Environmental pollution of toxaphene and toxaphenelike compounds generated in chlorobleaching process. II. Concentration and congener pattern of polychlorinated pinenes in fish. Kankyo Kagaku. 2:364–365. Kringstad, K. P., and Lindstrom, K. 1984. Spent liquors from pulp bleaching. Environ. Sci. Technol. 18:236A–248A. Larson, R. A., and Marley, K. A. 1986. Formation of Toxaphene-Like Contaminants During Simulated Paper Pulp Bleaching. Water Resource Center, University of Illinois, Urbana, IL. WRC 205. Miskimmin, B. M., Muir, D. C. G., Schindler, D. W., Stern, G. A., and Grift, N. P. 1995. Chlorobornanes in sediments and fish 30 years after toxaphene treatment of lakes. Environ. Sci. Technol. 29:2490–2495. Pearson, R. F., Swackhamer, D. L., Eisenreich, S. J., and Long, D. T. 1997. Concentrations, accumulations, and inventories of toxaphene in sediments of the Great Lakes. Environ. Sci. Technol. 31:3523–3529. Rapaport, R. A., and Eisenreich, S. J. 1988. Historical atmospheric inputs of high molecular weight chlorinated hydrocarbons to eastern North America. Environ. Sci. Technol. 22:931–941. Rappe, C., Haglund, P., Anderson, R., and Buser, H. 1998. Search for chlorobornanes in river sediments: Part 2. Organohalogen Compounds 35:291–294. Simcik, M. F., Eisenreich, S. J., Golden, K. A., Liu, S. Lipiatou, E., Swackhamer, D. L., and Long, D. T. 1996. Atmospheric loading of polycyclic aromatic hydrocarbons to Lake Michigan as recorded in the sediments. Environ. Sci. Technol. 30:3039–3046. Swackhamer, D. L., Charles, M. J., and Hites, R. A. 1987. Quantitation of toxaphene in environmental samples using negative ion chemical ionization mass spectrometry. Anal. Chem. 59:913–917. ———, Eisenreich, S. J., and Long, D. T. 1996. Atmospheric Deposition of Toxic Contaminants to the Great Lakes: Assessment and Importance. Volume II. PCDDs, PCDFs and Toxaphene in Sediments of the
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Great Lakes. Report to the U.S. EPA and the Great Lakes Protection Fund. Voldner, E. C., and Li, Y. F. 1993. Global usage of toxaphene. Chemosphere 27:2073–2078. ———, and Schroeder, W. H. 1989. Modeling of atmospheric transport and deposition of toxaphene into the Great Lakes ecosystem. Atmos. Environ. 23:1949–1961. Von Rumker, R. A., Lawless, W., Neiners, A. F., Lawrence, K. A., Kelso, G. C., and Horaz, F. 1975. A
Case Study of the Efficiency of the Use of Pesticides on Agriculture. U. S. EPA. 540/9–75–025. Wong, C. S., Sanders, G., Engstrom, D. R., Long, D. T., Swackhamer, D. L., and Eisenreich, S. J. 1995. Accumulation, inventory, and diagenesis of chlorinated hydrocarbons in Lake Ontario sediments. Environ. Sci. Technol. 29:2661–2672. Submitted: 16 November 1998 Accepted: 6 March 1999 Editorial handling: Peter F. Landrum
Are Pulp and Paper Mills Sources of Toxaphene to Lake Superior and Northern Lake Michigan? Kathryn E. Shanks, Jeffrey G. McDonald, and Ronald A. Hites* School of Public and Environmental Affairs and Department of Chemistry Indiana University Bloomington, Indiana 47405 ABSTRACT. Toxaphene was a broad-spectrum pesticide consisting of a mixture of highly chlorinated bornanes and bornenes. After its ban in 1982, toxaphene concentrations have shown a general decline in the environment as a whole and in most of the Great Lakes specifically. Recent work, however, shows that toxaphene concentrations are not decreasing in fishes from Lake Superior and northern Lake Michigan. Non-atmospheric, relatively localized sources are a possible explanation for these observations. For example, toxaphene could be inadvertently produced and released by pulp and paper mills, which could be synthesizing toxaphene-like compounds as a byproduct of bleached paper production. Reported here is a study of surficial river sediment collected upstream and downstream from seven pulp and paper mills, from five areas of previous toxaphene use, and from two presumed pristine locations. Concentrations of toxaphene found downstream are similar to those found upstream from each of the pulp and paper mills. Concentrations in sediment from rivers near previous toxaphene use locations were higher than concentrations in the background samples. These data suggest that pulp and paper mills are not now sources of toxaphene but that toxaphene used as a pesticide in the Great Lakes basin (although these uses were very small compared to its use in the southern US) could be a potential source. INDEX WORDS: Toxaphene, paper mills, Lake Superior, Lake Michigan, sediment.
INTRODUCTION Toxaphene was a broad-spectrum insecticide consisting of a mixture of bornanes and bornenes substituted with up to 10 chlorines (Hartley and Kidd 1983). The Hercules Company first produced toxaphene in 1947 by the photochlorination of camphene, an isomerization product of α-pinene, which was in turn isolated from softwoods such as conifers (Rapaport and Eisenreich 1988). Commercial toxaphene consisted of approximately 600 congeners (Jansson and Wideqvist 1983), of which less than 30 have been individually isolated and characterized. During the late 1960s and early 1970s, toxaphene was the replacement of choice for DDT, and at that time, toxaphene was the most heavily used insecticide in the United States (Howdeshell and Hites 1996). Toxaphene was primarily used in the southern US as an insecticide for cotton, but its use was eventually broadened to killing insects on livestock 1Corresponding
and to controlling rough fish in lakes (Voldner and Schroeder 1989; Bidleman et al. 1988). Toxaphene was used in the Great Lakes basin and Canada, but this use accounted for < 1% of its total use (Von Rumker et al. 1975). The U.S. Environmental Protection Agency (US EPA) banned toxaphene in 1982, although existing stocks could still be used under certain circumstances until 1986 (Fed. Regist. 1982). As of 1992, most developed countries had banned the use of toxaphene; however, it may still be used in some undeveloped countries (Voldner and Li 1993). Toxaphene is transported through the atmosphere to the Great Lakes, where it contaminates fish. Toxaphene concentrations in both lake trout and smelt from the Great Lakes seem to have responded to the ban in 1982 (Glassmeyer et al. 1997). For example, the toxaphene concentrations in trout from Lake Ontario decreased by about a factor of about 10 between 1982 and 1992. There are, however, two important yet puzzling exceptions: In Lake Superior and in northern Lake Michigan, the levels of toxaphene in trout and smelt have not changed over
author. E-mail: [email protected]
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the last 10 to 15 years (Glassmeyer et al. 1997). Why are fish from these two locations not showing the expected decline in toxaphene concentrations such as that observed in the other Great Lakes? There are two hypotheses: (a) The water in Lake Superior and northern Lake Michigan is colder than in the other Great Lakes, resulting in reduced airwater exchange and reduced degradation of toxaphene, and (b) Toxaphene is being supplied to Lake Superior and northern Lake Michigan by nonatmospheric sources. This paper addresses this second hypothesis. There are two non-atmospheric sources that could be delivering toxaphene to the Great Lakes: First, although the use toxaphene in the Midwest was slight, it is possible that farming the soil on which it had once been applied brings contaminated soil to the surface, and this process re-releases toxaphene into the environment. Second, it is possible that toxaphene-like compounds are produced and released by pulp and paper mills, which are numerous in the Great Lakes basin. This second idea requires some chemical elaboration. As mentioned above, toxaphene is produced by the photochlorination of camphene, an isomerization product of α-pinene (Fig. 1). Both camphene and α-pinene are present in the softwood pulp from which paper is made. In fact, a typical pulp and paper mill has a waste stream coming from the pulping process that contains terpenes that could act as potential precursors of toxaphene-like compounds (Kringstad and Lindstrom 1984). In addition, pulp and paper mills are intensive users of chlorine-based bleaching agents. On average, pulp and paper mills use 60 to 70 kg of chlorine per metric ton of pulp. The chemical forms of chlorine depend on the mill and bleaching process but include Cl 2 , ClO 2 , and ClO 4– (Kringstad and Lindstrom 1984). Thus, pulp and paper mills have all the nec-
FIG. 1.
Commercial synthesis of toxaphene.
essary ingredients for the inadvertent production of toxaphene-like compounds. If produced, these chlorinated by-products could be discharged into the mill’s receiving stream and eventually make their way to the Great Lakes. There is some literature to support the inadvertent production of toxaphene from the bleaching of paper. A study by Jarnuzi et al. (1992) found 90 ng/L and 80 ng/g of “toxaphene-like” compounds in water effluent and striped mullet fish, respectively, that had been collected near pulp and paper mills. In that study, the pentachlorinated homologue was the most predominant. Laboratory studies have also verified that camphene can be chlorinated under conditions ranging from complete darkness to simulated and real sunlight and at pHs of 2 and 8. At pH 2, the toxaphene-like products had chlorination levels which ranged from 2 to 5 in the dark and 2 to 9 under lighted conditions, depending on the time allowed for the reaction to take place (Larson and Marley 1986). At pH 8, small amounts of mono- and dichlorinated toxaphene-like products were formed under both dark and lighted conditions. To determine if these laboratory results can be extrapolated to the natural environment and to determine if pulp and paper mills are potential sources of toxaphene-like compounds to the Great Lakes, toxaphene was measured in sediment collected upstream and downstream from the discharge points of seven pulp and paper mills, most of which now use chlorine dioxide in their bleaching processes (J. Schwartz, American Forst and Paper Association, personal communication, 1998). If the mills were discharging toxaphene, relatively elevated concentrations downstream from the mills should be observed. As controls, toxaphene was also measured near locations where it may have been used for agricultural purposes and at pristine locations
Are Paper Mills Sources of Toxaphene? TABLE 1.
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Sample locations and descriptions.
Site Rainy River Menominee River Escanaba River Peshtigo River Wisconsin River Wisconsin River
Abbr.a RA ME ES PE WI WI
Fish Lake Mississippi River
FL MN
Saginaw River SA Sheboygan River SH Root River R Grand River G Sand Lake SN aSee Figure 2 for locations bOperated by Georgia-Pacific Corp.
Location International Falls, MN Quinnesec, MI Escanaba, MI Peshtigo, WI Port Edwards, WI Nekoosa, WI
Mill Boise Cascade Champion Paper Mead Paper Badger Paper Consolidated Paper Port Edwards and Nekoosa Paperb
Type Pulp and paper Pulp and paper Pulp and paper Pulp and paper Pulp and paper Pulp and paper
Stark, MN Bemidji, MN
Background Background
Saginaw, MI Sheboygan Falls, WI Racine, WI Grand Haven, MI Scandia, MN
Previous toxaphene use Previous toxaphene use Previous toxaphene use Previous toxaphene use Previous toxaphene use
where toxaphene should only have been delivered by the atmosphere. EXPERIMENTAL METHODS Sampling Sediment samples were collected in March and July of 1997 in conjunction with the US EPA; one of the authors (KES) was present at both times. The locations of the sampling sites are listed in Table 1 and shown in Figure 2. For the pulp and paper mill sites, six samples (in close proximity to one another) were collected above and below each mill. The Wisconsin River site was sampled at three locations because there were three mills discharging their effluent into the same river. The lower two mills shared a common effluent discharge source. Samples were taken between the two discharge points as well as above and below them. The sediment collected from all sites was divided and splits were given to the mill from where the sample was obtained. Distances from the mills to where the samples were collected were all less than 0.4 km. Sediments (three replicates in close proximity to one another) were also collected from rivers that drain areas where the US EPA indicated that toxaphene had been used as a pesticide. Sand Lake, a known toxaphene use location, was sampled once to obtain a deep piston core, which was sub-divided into 13 sub-samples. Background samples (also
three replicates) were collected from pristine lakes and rivers that were assumed to be free of any input of toxaphene other than from atmospheric deposition. Samples were collected using three different methods depending on location, accessibility, and the nature of the sediment. In March 1997, the cores were collected with a 5 cm diameter gravity corer (hand-built by the Minnesota Pollution Control Agency staff). In July 1997, the cores were collected with a 5 cm diameter commercial sediment corer (WildCo Wildlife Supply, Saginaw, MI). When sediment conditions would not allow the use
FIG. 2. Map of sampling sites; sampling site codes reported in Table 1.
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of corers on the July sampling trip, sediment was collected with an Eckman dredge sampler (WildCo Wildlife Supply). Samples were collected by wading or from a boat or bridge depending on the accessibility of the site. Sediment from core tubes was extruded, and the top 5 to 10 cm was retained for analysis. Samples from the dredge sampler were directly transferred into collection jars. A single 65cm deep sediment core was collected from Sand Lake. This core was sectioned every 5 cm. After being filled, the sample jars were placed in coolers with ice, shipped back to the laboratory, and stored at 4°C until they were warmed to room temperature for extraction.
toxaphene peaks. This file was imported into a QBasic program, which selected toxaphene peaks using chlorine isotope ratios and corrected for carbon-13 and other interferences.
Extraction and Analysis Sample preparation, extraction, clean up, and other details have been described elsewhere (Howdeshell and Hites 1996). The one exception to this published method was the use of 13Cl1-chlordane (Cambridge Isotope Laboratories, Cambridge, MA) as the internal standard. Toxaphene was quantitated by gas chromatographic mass spectrometry (Hewlett Packard 5989A or 5973) operated in the electron capture, negative ionization mode. The instruments were equipped with 30 m, DB-5MS columns (internal diameter, 250 µm; film thickness, 0.25 µm; J&W Scientific, Folsom, CA). The injection port was operated in the splitless mode at 285°C with a 1.9 min. vent time. Helium was the carrier gas at a velocity of 25 cm/s, and the injection volume was 1 µL. The temperature program began at 40°C for 1 min; the temperature was then ramped at 10°C/min to 200°C, at 1.5°C/min to 230°C, and at 10°C/min to a final temperature of 300°C, where it was held for 5 minutes. The transfer line connecting the GC to the MS was at 300°C, and the ion source was at 125°C. The reagent gas was methane at a pressure of 0.43 Torr as measured in the ion source by a direct insertion probe in the 5989A instrument. Data were acquired using the selected ion monitoring method based on ions suggested by Swackhamer et al. (1987). A relative response factor standard of Hercules toxaphene was run every 5 samples. Quantitation used a software system recently described by Glassmeyer et al. (1999). Briefly, peaks in the background-subtracted chromatogram were integrated using Hewlett Packard’s EnviroQuant program. These data were then imported into a macro (written in-house), which generated a file of retention times and areas of potential
RESULTS AND DISCUSSION The results of this study are presented in Table 2 and summarized in Table 3. While there were considerable variations within the six (or three) replicates, only an arithmetic average and standard error of the non-zero concentrations are reported in Table 3. Using these average statistics and paired Student’s t-tests, it was found that the concentrations of toxaphene in sediments downstream from each mill’s effluent discharge point are not significantly different (at the 90% confidence level) from those upstream. On average, the concentrations of toxaphene in sediments upstream from the mills ranged from 1.4 to 8.3 ng/g, and downstream from the mills, the concentrations ranged from 1.5 to 8.7 ng/g. From these data, it can be concluded that these pulp and paper mills are probably not now sources of toxaphene to the Great Lakes. With the exception of the Sand Lake site, the average concentration of toxaphene in the sediment samples collected from rivers that drain previous toxaphene use areas ranged from 6.0 to 43 ng/g. These concentrations were somewhat higher than those in the samples collected near the pulp and paper mills. The average toxaphene concentrations at the two background sites were 0.3 and 0.5 ng/g, values much lower than those observed at all of the other sites. The samples from Sand Lake were in the form of a chronologically segmented core. In this case, the six upper sections had higher toxaphene concentrations (0.2 to 3.6 ng/g) as compared to the lower sections (not detected to 1.0 ng/g). The upper sections are comparable to the previous toxaphene use samples, and the lower sections are comparable to the background sites. The elevated concentrations in previous use areas compared to the background sites suggests that some of
Loss-on-ignition LOI was determined for all samples. Sediment samples were weighed, placed in crucibles, and dried at 105°C for 24 hours to remove water. Samples were then re-weighed and heated in a muffle furnace at 525°C for 24 hours and weighed again. Total organic carbon was estimated by dividing the LOI by 1.724 (Howard and Howard 1990).
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TABLE 2. Summary of locations sampled, toxaphene concentrations per homologue, total toxaphene per dry weight of sediment, loss-on-ignition (LOI), total organic carbon (TOC), and total toxaphene per gram organic carbon. In this table “n” means not detected at a limit of detection of about 0.05 ng/g dry sediment per homologue. Rounding of the data to one decimal place may cause slight apparent errors in addition.
GPS Coordinates Code Lat./Lon. Rainy River, Upstream RA 1-1 48 35 38.8N/93 09 27.6W RA 1-2 48 35 37.1N/93 09 25.2W RA 1-3 48 35 38.4N/93 09 24.2W RA 1-4 48 35 37.1N/93 09 25.2W RA 1-5 48 35 36.5N/93 09 19.5W RA 1-6 48 35 38.8N/93 07 19.3W Average Std err Rainy River, Downstream RA 2-1 48 50 30.0N/94 41 44.8W RA 2-2 48 50 31.0N/94 41 38.8W RA 2-3 48 50 33.3N/94 41 41.6W RA 2-4 48 50 30.2N/94 41 38.6W RA 2-5 48 50 33.3N/94 41 38.6W RA 2-6 48 50 33.4N/94 41 35.1W Average Std err Menomenee River, Upstream ME 1-1 45 46 00.8N/87 58 25.5W ME 1-2 45 46 06.4N/87 58 57.7W ME 1-3 45 46 00.3N/87 58 35.9W ME 1-4 45 45 59.0N/87 58 20.5W ME 1-5 45 45 54.2N/87 58 04.9W ME 1-6 45 45 50.5N/87 58 04.9W Average Std err Menomenee River, Downstream ME 2-1 45 45 33.5N/87 54 26.7W ME 2-2 45 45 30.9N/87 54 33.5W ME 2-3 45 45 26.0N/87 54 36.0W ME 2-4 45 45 25.3N/87 54 49.4W ME 2-5 45 45 30.1N/87 54 53.7W ME 2-6 45 45 28.5N/87 55 12.3W Average Std err Escanaba River, Upstream ES 1-1 45 50 24.0N/87 05 28.7W ES 1-2 45 50 24.6N/87 05 28.3W ES 1-3 45 50 25.3N/87 05 27.3W ES 1-4 45 50 27.1N/87 05 26.9W ES 1-5 45 50 28.7N/87 05 26.4W ES 1-6 45 50 26.7N/87 05 17.6W Average Std err
Date Collected
Toxaphene (ng/g dry sed.) Toxaphene by homologue ng/g dry LOI 6 7 8 9 10 sed %
Toxaphene ng/g TOC Organic % Carbon
Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97
0.1 n 0.1 0.1 n 0.1 0.1 0.02
0.5 n 1.3 3.5 0.5 0.6 1.3 0.6
n n 0.2 n n 0.2 0.1 0.06
0.1 n 0.1 n 0.2 n 0.2 n 0.1 n 0.2 0.4 0.1 0.2 0.02
0.7 0.1 1.8 3.7 0.6 1.4 1.4 0.5
15.4 6.8 16.0 38.9 10.8 16.5 17.4 4.6
9.1 4.0 9.4 22.9 6.4 9.7 10.2 2.7
8 2 19 16 9 15 11 3
Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97
n 2.6 0.2 0.2 0.1 0.1 0.7 0.5
0.1 1.0 0.8 0.8 0.3 0.4 0.6 0.1
0.3 0.1 n n 0.1 n 0.2 0.1
n 0.8 0.2 0.1 n 0.4 0.4 0.2
n 0.1 n n n n 0.1
0.4 4.6 1.2 1.2 0.5 1.0 1.5 0.6
18.9 6.0 5.9 4.3 4.5 5.1 7.5 2.3
11.1 3.5 3.5 2.6 2.6 3.0 4.4 1.4
4 131 35 46 18 32 44 18
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
n n 14.9 n n n 14.9
0.7 2.7 7.0 n n 0.2 2.7 1.5
n 0.1 1.2 0.1 n 6.0 n 0.6 0.2 n n 10.0 0.7 3.4 0.5 2.0
n n 1.3 n 0.1 n 0.7 0.6
0.8 4.0 29.2 0.6 0.3 10.2 7.5 4.6
2.5 2.2 4.1 7.9 1.0 2.2 3.3 1.0
1.5 1.3 2.4 4.6 0.6 1.3 1.9 0.6
55 301 1201 13 57 804 405 200
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
n n n 0.1 n n 0.1
0.6 6.5 5.0 2.2 n 7.8 4.4 1.3
n 0.6 1.3 13.1 n 4.1 n 0.1 0.6 0.4 n 3.1 0.9 3.6 0.4 2.0
n 1.7 1.9 n n 3.1 2.3 0.4
1.2 22.7 11.0 2.4 1.0 14.0 8.7 3.6
3.9 7.7 6.3 3.8 5.2 6.0 5.5 0.6
2.3 4.5 3.7 2.2 3.0 3.5 3.2 0.4
51 502 298 111 32 399 232 80
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
n n n n 0.1 n 0.1
n 1.5 n 2.9 40.3 0.3 11.2 9.7
n 0.2 n 0.1 n 0.6 0.3 0.1
n 1.8 n 3.7 41.1 3.1 8.3 6.6
68.2 76.1 9.8 50.7 3.9 6.9 36.0 13.4
40.1 44.8 5.8 29.8 2.3 4.1 21.2 7.9
n 4 n 12 1768 76 465 434 (Continued)
n n n n n n
n 0.2 n 0.7 0.6 2.3 0.9 0.5
388 TABLE 2.
Shanks et al. Continued
GPS Coordinates Code Lat./Lon. Escanaba River, Downstream ES 2-1 45 48 23.3N/87 05 52.3W ES 2-2 45 48 25.8N/87 05 55.7W ES 2-3 45 48 39.3N/87 05 59.2W ES 2-4 45 48 39.8N/87 06 00.8W ES 2-5 45 48 41.7N/87 06 01.8W ES 2-6 45 48 27.1N/87 05 56.9W Average Std err Peshtigo River, Upstream PE 1-1 45 03 35.3N/87 44 48.1W PE 1-2 45 03 58.1N/87 44 40.6W PE 1-3 45 04 03.5N/87 44 38.9W PE 1-4 45 04 10.7N/87 44 35.4W PE 1-5 45 04 24.9N/87 44 39.5W PE 1-6 45 03 36.3N/87 44 52.5W Averagee Std err Peshtigo River, Downstream PE 2-1 45 02 46.7N/87 44 42.6W PE 2-2 45 02 44.3N/87 44 39.6W PE 2-3 45 02 40.2N/87 44 39.1W PE 2-4 45 02 34.8N/87 44 37.4W PE 2-5 45 02 28.3N/87 44 35.7W PE 2-6 45 02 25.4N/87 44 34.6W Average Std err Wisconsin River, Upstream WI 1-1 44 26 44.2N/89 43 26.0W WI 1-2 44 26 55.4N/89 43 04.5W WI 1-3 44 26 59.3N/89 42 20.0W WI 1-4 44 27 06.4N/89 41 14.8W WI 1-5 44 27 12.8N/89 41 15.5W WI 1-6 44 27 09.4N/89 41 49.5W Average Std err Wisconsin River, Middle WI M-1 44 22 27.1N/89 51 01.1W WI M-2 44 22 27.2N/89 51 04.9W WI M-3 44 22 39.9N/89 50 45.3W WI M-4 44 22 41.3N/89 50 42.4W WI M-5 44 23 03.9N/89 50 09.2W WI M-6 44 23 04.4N/89 50 09.8W Average Std err
Date Collected
Toxaphene (ng/g dry sed.) Toxaphene by homologue ng/g dry LOI 6 7 8 9 10 sed %
Toxaphene ng/g TOC Organic % Carbon
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
0.2 n n 31.0 n 0.1 10.4 10.3
0.4 n 0.9 0.1 0.2 n 0.4 0.2
n n 0.1 0.2 0.4 n 0.2 0.1
0.2 0.6 0.1 0.2 1.2 2.1 0.7 0.3
0.1 n n n n 0.1 0.1
0.9 0.6 1.1 31.4 1.7 2.3 6.3 5.0
0.8 0.9 4.0 21.9 5.5 1.7 5.8 3.3
0.5 0.5 2.3 12.9 3.3 1.0 3.4 1.9
189 106 45 244 54 227 144 36
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
n n n n n n
1.0 3.0 1.6 n 0.3 2.6 1.7 0.5
n n n n n 0.5 0.5
0.1 n 0.1 1.0 0.7 0.1 0.4 0.2
n n n n 0.2 0.1 0.2 0.1
1.0 3.0 1.6 1.0 1.4 3.2 1.9 0.4
4.9 0.8 3.1 1.2 10.1 7.8 4.6 1.5
2.9 0.5 1.8 0.7 5.9 4.6 2.7 0.9
36 663 90 139 22 71 170 100
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
n n 8.1 n 0.3 n 4.2 3.9
0.1 0.9 7.2 n 0.6 0.8 1.9 1.3
n 0.3 0.3 n n n 0.3
n 0.1 3.4 2.0 0.4 0.1 1.2 0.6
n n 0.9 1.8 n n 1.3 0.4
0.1 1.3 19.8 3.7 1.4 0.9 4.6 3.1
3.2 2.1 3.4 0.4 0.9 1.2 1.9 0.5
1.9 1.2 2.0 0.3 0.5 0.7 1.1 0.3
4 108 997 1453 262 133 493 241
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
n n n n n n n
0.5 1.0 n n 0.3 n 0.6 0.2
0.3 0.6 n 0.3 n n 0.4 0.1
0.1 0.3 0.3 1.1 n 4.9 1.3 0.9
0.1 0.1 n n n 2.4 0.8 0.8
1.0 2.0 0.4 1.4 0.3 7.3 2.0 1.1
3.6 3.6 2.2 0.7 1.1 0.5 1.9 0.6
2.1 2.1 1.3 0.4 0.6 0.3 1.1 0.3
46 95 28 329 42 2411 491 387
Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
n 0.4 n 10.4 n n 0.3 2.4 0.8 0.9 0.1 0.7 0.4 3.0 0.2 1.9
0.1 0.1 0.6 0.2 0.3 1.6 n 0.8 0.2 1.4 1.6 18.2 0.5 3.7 0.3 2.9
0.1 n 0.4 0.2 1.3 10.6 2.5 2.0
0.7 11.2 2.3 3.7 4.6 31.3 9.0 4.7
2.6 10.4 6.3 2.6 8.2 10.1 6.7 1.4
1.5 6.1 3.7 1.5 4.8 6.0 3.9 0.8
45 181 61 243 96 525 192 73 (Continued)
Are Paper Mills Sources of Toxaphene? TABLE 2.
389
Continued
GPS Coordinates Code Lat./Lon. Wisconsin River, Downstream WI 2-1 44 18 24.1N/89 53 51.4W WI 2-2 44 18 20.7N/89 53 40.6W WI 2-3 44 18 12.3N/89 53 36.4W WI 2-4 44 18 05.6N/89 53 33.3W WI 2-5 44 17 59.1N/89 53 29.9W WI 2-6 44 17 48.0N/89 53 31.3W Average Std err
Date Collected Jul-97 Jul-97 Jul-97 Jul-97 Jul-97 Jul-97
Grand River, Previous use G1 43 02 41.1N/86 09 39.9W G2 43 03 09.6N/86 09 52.3W G3 43 03 26.7N/86 10 33.1W Average Std err Root River, Previous use R1 42 43 44.7N/87 47 36.1W R2 42 43 47.1N/87 47 23.5W R3 42 44 00.4N/87 46 45.4W Average Std err Saginaw River, Previous use SA 1 43 29 21.2N/83 54 29.4W SA 2 43 30 06.5N/83 53 37.8W SA 3 43 31 47.9N/83 52 56.1W Average Std err Sheboygan River, Previous use SH 1 43 43 53.2N/87 48 46.7W SH 2 43 43 44.7N/87 48 51.8W SH 3 43 43 39.6N/87 48 59.0W Average Std err
Toxaphene ng/g TOC Organic % Carbon
n n 0.3 n 0.7 n 0.5 0.2
n 0.9 n n 2.2 n 1.6 0.6
n 5.3 n n 0.2 n 2.7 2.6
0.4 5.0 0.9 n 4.4 9.7 4.1 1.7
n 0.3 n n 2.6 3.4 2.1 0.9
0.4 11.6 1.2 n 10.1 13.1 7.3 2.7
1.4 0.7 0.7 1.2 2.6 0.3 1.2 0.3
0.8 0.4 0.4 0.7 1.5 0.2 0.7 0.2
50 2852 278 n 658 6504 2069 1216
n n n
0.1 n 0.1 0.1
0.3 n n 0.3
0.1 n n
n n n
0.5 n 0.1 0.3 0.2
27.2 27.1 27.0 27.1 0.1
16.0 16.0 15.9 16.0 0.1
3 n 1 2 1
Mar-97 Mar-97 Mar-97
n 0.1 0.1 0.1 0.0
n 0.2 0.4 0.3 0.1
n n 0.1 0.1
n n 0.1 0.1
n n n
n 0.3 0.7 0.5 0.2
17.5 18.8 15.8 17.4 0.9
10.3 11.1 9.3 10.2 0.5
n 2 8 5 2
Mar-97 Mar-97 Mar-97
1.3 n 0.7 1.0 0.3
6.9 1.4 2.7 3.7 1.7
1.6 n 1.8 1.7 0.1
1.3 n 0.2 0.7 0.5
0.2 n n 0.2
11.2 1.5 5.4 6.0 2.8
2.0 2.5 2.6 2.4 0.2
1.2 1.5 1.6 1.4 0.1
940 99 346 461 249
Jul-97 Jul-97 Jul-97
0.3 20.9 1.1 7.4 6.7
31.0 34.8 24.9 30.2 2.9
3.4 0.7 4.6 2.9 1.2
0.2 1.0 2.2 1.1 0.6
0.61 0.5 1.7 0.9 0.4
35.4 57.9 34.6 42.6 7.6
2.7 3.6 9.2 5.2 2.0
1.6 2.1 5.4 3.1 1.2
2213 2717 635 1855 627
Jul-97 Jul-97 Jul-97
n n n
10.8 2.4 19.6 10.9 5.0
0.2 n 3.3 1.7 1.6
2.8 0.1 1.0 1.3 0.8
0.4 n 0.2 0.3 0.1
14.1 2.5 24.2 13.6 6.3
15.5 1.4 3.0 6.7 4.5
9.1 0.8 1.8 3.9 2.6
155 300 1348 601 376
Jul-97 Jul-97 Jul-97
n 0.5 n 0.5
15.7 31.8 n 23.8 8.0
n 0.8 n 0.8
0.1 0.6 7.7 2.8 2.5
n n 1.2 1.2
15.9 33.7 9.0 19.5 7.4
11.3 1.2 4.2 5.5 3.0
6.6 0.7 2.5 3.3 1.8
239 4872 365 1826 1524 (Continued)
Mississippi River, Background MN 1 information MN 2 not MN 3 available Average Std err Fish Lake, Background FL 1 45 34 38.8N/93 01 30.8W FL 2 45 34 35.6N/93 01 31.1W FL 3 45 34 37.2N/93 01 27.6W Average Std err
Toxaphene (ng/g dry sed.) Toxaphene by homologue ng/g dry LOI 6 7 8 9 10 sed %
390
Shanks et al.
TABLE 2.
Continued
GPS Coordinates Code Lat./Lon. Sand Lake, Previous use SN 1 45 13 46.3N/92 48 14.8W SN 2 45 13 46.3N/92 48 14.8W SN 3 45 13 46.3N/92 48 14.8W SN 4 45 13 46.3N/92 48 14.8W SN 5 45 13 46.3N/92 48 14.8W SN 6 45 13 46.3N/92 48 14.8W SN 7 45 13 46.3N/92 48 14.8W SN 8 45 13 46.3N/92 48 14.8W SN 9 45 13 46.3N/92 48 14.8W SN 10 45 13 46.3N/92 48 14.8W SN 11 45 13 46.3N/92 48 14.8W SN 12 45 13 46.3N/92 48 14.8W SN 13 45 13 46.3N/92 48 14.8W Average Std err
TABLE 3.
Date Collected Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97 Mar-97
Toxaphene (ng/g dry sed.) Toxaphene by homologue ng/g dry LOI 6 7 8 9 10 sed % 0.1 0.1 0.8 0.2 0.1 0.1 0.1 n n 0.1 n n n 0.2 0.1
0.1 1.4 2.8 1.2 1.6 0.6 0.2 0.1 0.1 0.5 n 0.2 n 0.8 0.3
n 0.2 n n 0.2 0.6 n n n n n n n 0.3 0.1
n n n n n 0.1 0.1 0.1 n n n n 1.0 0.3 0.2
n n n n n n n n n n n n n
0.2 1.8 3.6 1.5 2.0 1.3 0.4 0.2 0.1 0.5 n 0.2 1.0 1.1 0.3
23.2 16.7 15.2 15.4 16.2 18.3 20.9 21.0 19.9 31.6 25.7 25.5 7.7 19.8 1.7
Toxaphene ng/g TOC Organic % Carbon 13.7 9.8 8.9 9.1 9.5 10.8 12.3 12.4 11.7 18.6 15.1 15.0 4.5 11.6 1.0
1 18 40 16 21 12 3 2 1 3 n 1 22 11 3
Summary of toxaphene concentrations and standard errors.
Mill Boise Cascade
Abbr. RA
Champion Paper
ME
Mead Paper
ES
Badger Paper
PE
Consolidated Paper Port Edwards and Nekoosa Paper
WI WI WI
Location Upstream Downstream Upstream Downstream Upstream Downstream Upstream Downstream Upstream Middle Downstream
these areas could be potential sources of toxaphene to the environment, where it could make its way into the Great Lakes. However, it is not possible to estimate how much toxaphene this process might be contributing to Lake Superior or to northern Lake Michigan. These measurements of toxaphene in sediment are compared to some previously reported measurements in Table 4. The previously reported toxaphene concentrations in Lakes Ontario, Michi-
Toxaphene ng/g dry sediment 1.4 ± 0.5 1.5 ± 0.6 7.5 ± 4.6 8.7 ± 3.6 8.3 ± 6.6 6.3 ± 5.0 1.9 ± 0.4 4.6 ± 3.1 2.0 ± 1.1 9.0 ± 4.7 7.3 ± 2.7
Toxaphene ng/g organic carbon 11 ± 3 44 ± 18 410 ± 200 230 ± 80 460 ± 430 140 ± 36 170 ± 100 490 ± 240 490 ± 390 190 ± 70 2,100 ± 1,200
gan, and Superior sediments range from 3 to 45 ng/g, values which are similar to the concentrations reported here for sediment in rivers near pulp and paper mills and near sites of previous toxaphene use, which range from 1.4 to 43 ng/g. Previously reported toxaphene concentrations at other background locations range from 0.6 to 9 ng/g, values which are somewhat higher than the 0.3 and 0.5 ng/g obtained at the background locations of this study. Averaging the samples from Sand Lake over
Are Paper Mills Sources of Toxaphene? TABLE 4. Toxaphene concentrations in selected sediments. Site Rivers near pulp and paper mills Rivers near previous usage sites
Conc. (ng/g dry wgt.) 1.4–9.0 6.0–43
Lake Ontariob Lake Ontarioc Lake Michiganb Lake Superiora Lake Superiorb
15 10–20 15–45 3–15 15
Sand Lake Siskiwit Lakea Outer Islanda Apostle Islandsb Lake Nipigond Mississippi River Fish Lake aPearson et al. (1997) bSwackhamer et al. (1996) cHowdeshell and Hites(1996) dStern and Muir (unpublished data)
1 9 4 4–9 0.6–3 0.3 0.5
the entire core gave a toxaphene concentration of 1 ng/g, a value comparable with other background locations. Because hydrophobic organic contaminants such as toxaphene preferentially associate with organic matter in sediments, the data were also normalized to organic carbon (last column of Table 2). The upstream and downstream averages are also summarized in Table 3. Like the dry weight normalized data, these organic carbon normalized data did not show significantly higher toxaphene concentrations downstream from the pulp and paper mills either. These comparisons support the conclusion that pulp and paper mills are probably not now sources of toxaphene to Lake Superior or to northern Lake Michigan. Rappe et al. (1998) analyzed the sample splits that were provided to the Georgia Pacific Co., and in most cases, these authors found less than about 0.2 ng/g dry weight of total toxaphene. These values seem unusually low, being about 1 to 5% of the concentrations reported here in the same samples. The difference in these results between the two laboratories may indicate a possible bias inherent in one or both of the toxaphene analytical methods. It should be pointed out that all of the data in Table 4 were obtained with the Swackhamer et al. (1987) method while the Rappe et al. (1998) data were ob-
391
tained with another method. It is possible that the differences between the two data sets for the Georgia Pacific samples are due to differences in the two methods. It is important to note, however, that neither laboratory finds significant differences in toxaphene concentrations in sediment samples collected from upstream and downstream of pulp and paper mills. The homologue profiles for toxaphene from river sediments near the five pulp and paper mill locations are shown in Figure 3. With the exception of the Wisconsin River, the homologue profiles are not consistent between the upstream and downstream samples near each mill and are not consistent with the commercial mixture of Hercules toxaphene. The homologue profiles for the three samples from the Wisconsin River are consistent with one another, but they differ from the commercial mixture. Most of the homologue profiles for the toxaphene previous use areas and for the background locations (Fig.3) show that the hepta-chlorinated homologue is the most abundant homologue in these samples. Unfortunately the high variability of these homologue profiles prevents drawing firm conclusions about the source of toxaphene in these samples. Miskimmin et al. (1995) have observed that two specific hexa- and heptachlorinated toxaphene homologues (called “hex-sed” and “hep-sed”) are dominant in sediment samples from previous use locations. These authors attribute the presence of these homologues to anaerobic microbial reductive dechlorination of technical toxaphene. Initially, it was thought that these congeners might be present in the samples from the previous use areas as well. However, comparisons of the gas chromatographic retention times of the hexa- and heptachlorinated toxaphene congeners in the samples with those containing “hex-sed” and “hep-sed” showed that these two congeners were not significant components of the samples. Gary Stern, a co-author of the Miskimmin et al. (1995) study, also analyzed our previous use sediment extracts and did not see “hep-sed” or “hex-sed” present in any of the samples. There is considerable variability in the toxaphene concentrations, in the losses-on-ignition (LOI), and in the homologue profiles among the replicate samples taken at the same locations because of problems associated with sampling sediment in rivers. Sediment in rivers can vary dramatically over small spatial regions. For example, at one location, the sediment collected for this study ranged from rich organic sediment to sand to coarse gravel. In addition, the location of sediment deposition zones in a
392
Shanks et al.
FIG. 3. Toxaphene homologue profiles from sediments collected near pulp and paper mills, from previous toxaphene use locations, and from background locations and Hercules toxaphene.
Are Paper Mills Sources of Toxaphene? river can shift because of day-to-day and seasonal flow variations, because of the presence of ice, and because of human influences (such as damming of the rivers and motor boat use). Sediment focusing and defocusing in rivers may also be a major problem, and historic information on the presence of toxaphene could be lost if sediment defocusing were significant. Despite these problems, the sediment samples from these rivers analyzed in this study were sufficiently high in organic carbon to retain toxaphene. We reach this conclusion for two reasons: First, the toxaphene concentrations measured in these river sediments are similar to those measured in lakes, particularly the Great Lakes. Second, the LOI values, and by extension the total organic carbon values, are typical of those for sediments known to accumulate pollutants (Simcik et al. 1996, Baker et al. 1991, Wong et al. 1995). Although these results do not indict the pulp and paper industry as a current toxaphene source, it should be pointed out that things may have been different in the past, and they may be different in the future. Additional toxaphene measurements of mills’ effluent streams and of their various paper products would be helpful. ACKNOWLEDGMENTS We thank David DeVault, Harold Wiegner, Patricia King, Lawrence Lins, and Paul Novak, Jr. for their assistance in sampling. Special thanks go to Sharon Kendall for technical assistance and to Gary Stern for providing the “hex-sed” and “hep-sed” secondary standard. We thank the U.S. Environmental Protection Agency for funding (Grant X985360). REFERENCES Baker, J. E., Eisenreich, S. J, and Eadie, B. J. 1991. Sediment trap fluxes and benthic recycling of organic carbon, polycyclic aromatic hydrocarbons, and polychlorobiphenyl congeners in Lake Superior. Environ. Sci. Technol. 25:500–509. Bidleman, T. F., Zaranski, M. T., and Walla, M. D. 1988. In Toxic Contamination in Large Lakes Vol 1. Schmidtke, N. W., Ed., pp. 257–284. Chelsea, MI: Lewis Publishers. Fed. Regist. 1982. 47:53784. Glassmeyer, S. T., De Vault, D. S., Myers, T. R., and Hites, R. A. 1997. Toxaphene in Great Lakes fish: A temporal, spatial, and trophic study. Environ. Sci. Technol. 31:84–88.
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———, Shanks, K. E., and Hites, R. A. 1999. Automated toxaphene quantitation method. Anal. Chem. 71: 1448–1453. Hartley, D., and Kidd, H., Eds. 1983. The Agrochemicals Handbook. Nottingham, England: The Royale Society of Chemistry. Howard, P. J. A., and Howard, D. M. 1990. Use of organic carbon and loss-on-ignition to estimate soil organic matter in different soil types and horizons. Biol. Fertil. Soils. 9:306–310. Howdeshell, M. J., and Hites, R. A. 1996. Historical input and degradation of toxaphene in Lake Ontario sediment. Environ. Sci. Technol. 30:220–224. Jansson, B., and Wideqvist, U. 1983. Analysis of toxaphene (PCC) and chlordane in biological samples by NCI mass spectrometry. Int. J. Environ. Anal. Chem. 13:309–321. Jarnuzi, G., Matsuda, M., and Wakimoto, T. 1992. Environmental pollution of toxaphene and toxaphenelike compounds generated in chlorobleaching process. II. Concentration and congener pattern of polychlorinated pinenes in fish. Kankyo Kagaku. 2:364–365. Kringstad, K. P., and Lindstrom, K. 1984. Spent liquors from pulp bleaching. Environ. Sci. Technol. 18:236A–248A. Larson, R. A., and Marley, K. A. 1986. Formation of Toxaphene-Like Contaminants During Simulated Paper Pulp Bleaching. Water Resource Center, University of Illinois, Urbana, IL. WRC 205. Miskimmin, B. M., Muir, D. C. G., Schindler, D. W., Stern, G. A., and Grift, N. P. 1995. Chlorobornanes in sediments and fish 30 years after toxaphene treatment of lakes. Environ. Sci. Technol. 29:2490–2495. Pearson, R. F., Swackhamer, D. L., Eisenreich, S. J., and Long, D. T. 1997. Concentrations, accumulations, and inventories of toxaphene in sediments of the Great Lakes. Environ. Sci. Technol. 31:3523–3529. Rapaport, R. A., and Eisenreich, S. J. 1988. Historical atmospheric inputs of high molecular weight chlorinated hydrocarbons to eastern North America. Environ. Sci. Technol. 22:931–941. Rappe, C., Haglund, P., Anderson, R., and Buser, H. 1998. Search for chlorobornanes in river sediments: Part 2. Organohalogen Compounds 35:291–294. Simcik, M. F., Eisenreich, S. J., Golden, K. A., Liu, S. Lipiatou, E., Swackhamer, D. L., and Long, D. T. 1996. Atmospheric loading of polycyclic aromatic hydrocarbons to Lake Michigan as recorded in the sediments. Environ. Sci. Technol. 30:3039–3046. Swackhamer, D. L., Charles, M. J., and Hites, R. A. 1987. Quantitation of toxaphene in environmental samples using negative ion chemical ionization mass spectrometry. Anal. Chem. 59:913–917. ———, Eisenreich, S. J., and Long, D. T. 1996. Atmospheric Deposition of Toxic Contaminants to the Great Lakes: Assessment and Importance. Volume II. PCDDs, PCDFs and Toxaphene in Sediments of the
394
Shanks et al.
Great Lakes. Report to the U.S. EPA and the Great Lakes Protection Fund. Voldner, E. C., and Li, Y. F. 1993. Global usage of toxaphene. Chemosphere 27:2073–2078. ———, and Schroeder, W. H. 1989. Modeling of atmospheric transport and deposition of toxaphene into the Great Lakes ecosystem. Atmos. Environ. 23:1949–1961. Von Rumker, R. A., Lawless, W., Neiners, A. F., Lawrence, K. A., Kelso, G. C., and Horaz, F. 1975. A
Case Study of the Efficiency of the Use of Pesticides on Agriculture. U. S. EPA. 540/9–75–025. Wong, C. S., Sanders, G., Engstrom, D. R., Long, D. T., Swackhamer, D. L., and Eisenreich, S. J. 1995. Accumulation, inventory, and diagenesis of chlorinated hydrocarbons in Lake Ontario sediments. Environ. Sci. Technol. 29:2661–2672. Submitted: 16 November 1998 Accepted: 6 March 1999 Editorial handling: Peter F. Landrum