Ecological Research Series Chlorinated Hydrocarbons in the Lake Ontario Ecosystem (IFYGL) National Environmental Research Center Office of Research and Development U.S. Environmental Protection Agency Corvallis, Oregon 97330 ------- RESEARCH REPORTING SERIES Research reports of the Office of Research and Development, U.S. Environmental Protection Agency, have been grouped into five series. These five broad categories were established to facilitate further development and application of environmental technology. Elimination of traditional grouping was consciously planned to foster technology transfer and a maximum interface in related fields. The five series are: 1. Environmental Health Effects Research 2. Environmental Protection Technology 3. Ecological Research 4. Environmental Monitoring 5. Socioeconomic Environmental Studies This report has been assigned to the ECOLOGICAL RESEARCH STUDIES series. This series describes research on the effects of pollution on humans, plant and animal species, and materials. Problems are assessed for their long- and short-term influences. Investigations include formation, transport, and pathway studies to determine the fate of pollutants and their effects. This work provides the technical basis for setting standards to minimize undesirable changes in living organisms in the aquatic, terrestrial and atmospheric environments. EPA REVIEW NOTICE This report has been reviewed by the Office of Research and Development, EPA, and approved for publication. Approval does not signify that the contents necessarily reflect the views and policies of the Environmental Protection Agency, nor does mention of trade names or commercial products constitute endorsement or recommendation for use. ------- EPA-660/3-75-022 JUNE 1975 CHLORINATED HYDROCARBONS IN THE LAKE ONTARIO ECOSYSTEM (IFYGL) by Clarence L. Haile Gilman D. Veith G. Fred Lee William C. Boyle Grant #800608 Program Element 1BA026 ROAP/Task No. 21AKP/14 Project Officer Michael D. Mull in Grosse He Laboratory National Environmental Research Center Grosse lie, Michigan 48138 NATIONAL ENVIRONMENTAL RESEARCH CENTER OFFICE OF RESEARCH AND DEVELOPMENT U.S. ENVIRONMENTAL PROTECTION AGENCY CORVALLIS, OREGON 97330 For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 ------- ABSTRACT Lake Ontario fish, water, sediment, net plankton, Cladophora, and benthos were examined for DDT group pesticides, dieldrin, and PCBs. Endrin, BHC group pesticides, and heptachlor were also identified in some fish samples. Average concentrations ranged from 28 ng/1 (t-DDT, e.e., sum of DDT, DDE, and ODD), 4.8 ng/1 (dieldrin), and 55 ng/1 (PCBs as Aroclor 1254 equivalent) for water to 1.40 yg/g (t-DDT), 0.07 yg/g (dieldrin), and 5.15 yg/g (PCBs) for whole fish. DDE levels were generally similar to t-DDT levels, except for sediments where ODD and DDT contributed significantly to t-DDT values. PCB/t-DDT ratios averaged 2.6 for all samples except for sediment (7.0) and benthos (5.3). This report was submitted in fulfillment of Project Number R-800608, by the University of Wisconsin, under the (partial) sponsorship of the Environmental Protection Agency. Work was completed as of August 1974. -n- ------- CONTENTS Page Abstract ii Acknowledgements v Sections I Conclusions 1 II Recommendations 3 III Introduction 4 IV Methods 5 V Results and Discussion 13 VI References ' 27 -m- ------- TABLES No. Page 1 Gas Chromatographic Columns and Conditions. 10 2 Chlorinated Hydrocarbons and Fat in Lake Ontario Fish. 14 3 DDT and PCBs in Lake Ontario Fish Fat. 16 4 Chlorinated Hydrocarbons in Lake Ontario Water. 19 5 Chlorinated Hydrocarbons in Lake Ontario Sediment. 21 6 Chlorinated Hydrocarbons in Lake Ontario Net Plankton. 23 7 Chlorinated Hydrocarbons in Lake Ontario Cladophora. 25 8 Chlorinated Hydrocarbons in Lake Ontario Benthic Fauna. 25 ------- ACKNOWLEDGEMENTS We wish to thank John Carr, Nelson Thomas, Sam Mozley, Don McNaught, and the officers and crews of the Researcher, Advance II, and Kaho for their assistance in sample collection. Technical assistance was provided by Richard Pyter, Walter Gunthier, Katherine Benkert, Judy Capelli and Paul Choitz. We are especially grateful to David Armstrong for his review and comments on the manuscript. -v- ------- SECTION I CONCLUSIONS Lake Ontario fish, water, sediment, net plankton, Cladophora, and benthic fauna contained significant concentrations of DDT group pesticides, dieldrin, and PCBs. Endrin, heptachlor, and BHC group pesticides (especially lindane, y BHC) were also identified in some fish. Lake-wide concentrations of t-DDT, dieldrin, and PCBs (Arochlor 1254 equivalent) for fish (alewives, smelt, and slimy sculpin) ranged from 0.95 to 1.40 yg/g, 0.04 to 0.07 yg/g, and 2.35 to 5.13 yg/g, respectively Lake Ontario water was found to contain "total" concentrations (dissolved + particulate) of 28 ng/1 , 4.8 ng/1, and 55 ng/1 for t-DDT, dieldrin, and PCBs. Water collected off Oswego contained comparatively high levels of DDT group pesticides, dieldrin, and PCBs, while waters off Hamilton contained higher t-DDT levels, and waters off the mouth of the Niagara River showed higher PCB concentrations. Average sediment t-DDT, dieldrin, and PCB concentrations were 22, 1.2, and 120 ng/g, respectively. Sediment off the mouth of the Welland Canal showed higher levels of all three contaminants while sediments off the mouth of the Niagara River contained higher levels of PCBs and dieldrin. Sediments off Oswego and at an eastern mid-lake site showed higher levels of PCBs and dieldrin, respectively. Average concentrations in net plankton were 3.5 yg/g (t-DDT), 0.12 yg/g (dieldrin), and 7.2 yg/g (PCBs). Corresponding concentrations in Cladophora were 229, 13, and 515 ng/g for t-DDT, dieldrin, and PCBs, respectively. Lake Ontario benthic fauna were found to contain 99, 6.9, and 471 ng/g t-DDT, dieldrin, and PCBs, respectively, with benthos taken off Hamilton exhibiting levels approximately four times benthos off Rochester and Oswego. -1- ------- High concentrations of PCBs in waters and sediments off the mouth of the Niagara River and Oswego indicate the importance of the Niagara and Oswego Rivers as inputs of PCBs associated with settlable particulates. In most cases, t-DDT concentrations were similar to concentrations of the DDT metabolite, DDE, except in sediments where DDT and ODD contributed much larger fractions. PCB/t-DDT ratios for all samples fell in the range of 1.9 to 3.1 except for sediment (7.0) and benthos (5.3). Relative chlorinated hydrocarbon concentrations for various segments of the Lake Ontario ecosystem were about 1; 2,500; 10,000; 150,000; and 300,000 for water, sediment, benthos, net plankton, and fish, relatively. Although these concentration differences indicated large accumulation factors for chlorinated hydrocarbons in fish, considerable additional information is required to elucidate mechanisms of chlorinated hydrocarbon transport and accumulation that will allow an assessment of the probable impact on the aquatic ecosystem when contaminant inputs to the lake are altered. -2- ------- SECTION II RECOMMENDATIONS Although Lake Ontario fish contained accumulated chlorinated hydro- carbons at levels several orders of magnitude higher than amounts in their food organisms and the lake water, processes of uptake and elimination of these contaminants by fish are uncertain. The mechanisms controlling these processes should be determined and their relative importance evaluated to aid in understanding the relationships between contaminant concentrations in water and in the associated biota. The elucidation of these relationships will allow an assessment of the probable impact on the aquatic ecosystem when contaminant inputs to the lake are altered. Since chlorinated hydrocarbons associated with the dissolved and particul- ate (organic and inorganic) fractions of lake waters may interact differently within the lake ecosystem, analytical methods should be developed to separate and quantitate the contaminant concentrations in these fractions. Lake Ontario waters and sediments near the mouths of the Niagara and Oswego Rivers were found to contain significantly higher concentrations of PCBs than the other waters and sediments sampled. This indicated the necessity to determine the levels and forms (dissolved or associated with particulates) of PCBs in these rivers to allow an assessment of their importance as sources of PCBs to the Lake Ontario ecosystem. Since fish are capable of accumulating chlorinated hydrocarbon concentra- tions several orders of magnitude higher than the surrounding water, Lake Ontario fish should be extensively examined for halogenated hydrocarbons not previously identified or confirmed in fish. Some compounds, although present in lake waters at undetected levels, may be of considerable importance due to their toxicities even at very low levels. -3- ------- SECTION III INTRODUCTION Measurements of pesticide residues in the Great Lakes have shown excessive levels of several chlorinated hydrocarbons. Polychlorinated biphenyls (PCBs) and DDT group pesticides (i.e., DDT, DDE, ODD, and related isomers) have been confirmed in Lake Michigan fish at levels exceeding U.S. Food and Drug Administration action limits, and dieldrin has been found at levels approaching the action limit (Veith, 1970; Reinert,1970). The pesticide contamination problem in Lake Ontario has received less attention than in Lake Michigan where residue concentrations in several segments of the ecosystem may be higher (Reinert, 1970; Veith, 1973). Although studies of chlorinated hydrocarbon contamination in Lake Ontario fish have been conducted (Reinert, 1970; Kaiser, 1974), information concerning other segments of the ecosystem is incomplete. This study was conducted as a part of the International Field Year for the Great Lakes to provide baseline information on the levels of DDT group pesticides, dieldrin, and PCBs in Lake Ontario fish, water, sediment, net plankton, Cladophora, and benthic fauna. This information will allow a more complete assessment of the chlorinated hydrocarbon problem in Lake Ontario and contribute to an understanding of chlorinated hydrocarbon transport in aquatic ecosystems. -4- ------- SECTION IV METHODS SAMPLING Alewives (Alosa pseudoharengusj, smelt (Osmerus mordax), slimy sculpin (Cottus cognatus), water, sediment, net plankton, Cladophora, and benthos samples were obtained from several near-shore and mid-lake sites on Lake Ontario during the summer of 1972. Sampling was more intensive near Rochester, Oswego, and Hamilton. Samples were also collected off Cobourg and Olcott, at the eastern end of the lake, and at four mid-lake sites. Figure 1 shows the locations of the sampling stations. Water samples were taken (Van Dorn type sampler) just below the surface, at 10 m below the surface, and at 10 m above the sediment at each station. Fish were trawl-netted at 18 to 73 m and mixed plankton netted (64 urn mesh opening) at 5 to 10 m. Cladophora was gathered at 1 to 2 m depths. Sediments were sampled with a Ponar grab, and benthos were captured using a epibenthic sled. All samples were transported and stored frozen or near 4°C in glass or metal containers to minimize chemical changes and contamination. EXTRACTION AND CLEANUP Fish Extraction and cleanup of whole fish were conducted according to the procedures described by Veith (1970). Frozen fish (a combined sample of at least eight individuals for each species captured at each site) were ground twice to homogenize the flesh before weighing out six 10 g sub-samples. Each sub-sample was blended with 70 g anhydrous Na^SO, and extracted for at least 4 hr with 170 ml of 1:1 ethyl ether-hexane (v/v) in an all-glass Soxhlet extractor. The extracts were concentrated to 20 ml in an air stream and 2 ml aliquots were removed for analysis of non-volitile fats and oils (residue after evaporation at 150°C for 20 min). The remaining extracts were subjected to liquid chromatographic cleanup and fractionation. The extracts were placed on 20 g columns of florisil (Fisher F-100, 60-100 mesh washed -5- ------- wsp wC TORONTO HAMILTON fb wfsbpC wp Figure 1. Lake Ontario sampling sites for chlorinated hydrocarbon analysis. Notations are: f-Fish, w-Water, s-Sediment, p-Net Plankton, C-Cladophora, b-Benthos. Station numbers are IFYGL station identifiers. ------- with hexane and activated by heating to 650°C for 2 hr) and topped with anhydrous NazSC^ to prevent deactivation of the fTori si 1 by water. The columns were sequentially eluted with 200 ml each of 6, 12, and 50% ether in hexane (v/v). Since preliminary gas chromatographic analysis of the 12 and 50% eluates failed to provide identification of compounds of interest, notably dieldrin and endrin, which were identified in the 6% eluates, only the 6% eluates were considered for subsequent examination. The presence of dieldrin and endrin in the less polar fractions likely resulted from some deactivation of the florisil by water vapor prior to use. The 6% eluates were concentrated (air stream) to 50 ml before removing 5 ml aliquots for preliminary gas chromatographic determination of DDE (generally the largest peak on the chromatogram). The remaining portions'were concentrated to less than 10 ml before placing on 20 g columns of silicic acid (washed with hexane, dried at 130°C overnight, and partially deactivated with 2.1% water). Elution with 250 ml hexane produced the PCB fractions. Further elution with 200 ml 3:1 dichloro- methane-hexane (v/v) allowed elution of the chlorinated pesticide fractions. These fractions were evaporated in an air stream, hexane was added, and the fractions were re-evaporated. This process was repeated several times to insure complete removal of the dichloromethane. Water Each water sample (10 1) was extracted at the collection site by passage through a column of six polyurethane foam plugs at a flow rate of 250 ml/min using the procedure described by Uthe et_ aj_. (1972). Preparation of the plugs involved Soxhlet extractions (at least 4 hr) with 1:1 ethyl ether- hexane (v/v) to remove contaminants followed by coating the plugs with a 1% solution of DC-200 silicone oil in hexane and air-drying. Following extraction of water samples, the plugs were removed from the column and again extracted (4 hr) with 1:1 ether-hexane (v/v). The columns were rinsed several times with acetone. The combined extracts from the plugs and column rinsings were reduced to about 5 ml in an air stream before cleanup by liquid chromatographic procedures similar to those for cleanup of fish extracts. -7- ------- Sediment Samples were allowed to air dry at room temperature before weighing out six 25 g sub-samples for analysis. The sub-samples were thoroughly ground by mortar and pestle, mixed with anhydrous NapSO., and extracted with 170 ml 1:1 ether-hexane (v/v) in all-glass Soxhlet extractors for 4 hr. The extracts were concentrated to about 10 ml before liquid chromatographic cleanup in a manner similar to that used for fish extracts. Net Plankton and Cladophora Net plankton and Cladophora samples were transferred to tared centrifuge tubes and sub-divided into sub-samples of about 1 g where appropriate. After centrifuging at 2000 rpm for 25 min, the supernatant was decanted rapidly into separatory funnels, 2 ml acetone was added to each tube, and the samples were allowed to air-dry. The tubes were weighed and sample dry weights were determined by difference. Water decanted from each tube was extracted twice with 25 ml of hexane to recover materials released from the cells. A 35 ml portion of the extract was added to the corresponding sample tube and the tube was shaken periodically over a 36 hr period. The extract was decanted and the residue extracted a second time with a 35 ml portion of fresh hexane. The combined extracts were concentrated to 5 ml for cleanup by procedures similar to those for fish extracts. Benthos Mixed benthic fauna (largely Pontiporeia affinis) were dried at room temperature and separated into at least three 10 g aliquots before extraction and cleanup by procedures identical to those used for sediment samples. PESTICIDE DETERMINATION Qualitative Determination Pesticide fractions of all fish and several water, sediment, plankton, Cladophora,and benthos extracts from silicic acid cleanup were ------- chromatographed (Varian Aerograph 1500 or 1700) on four gas chromatographic (GC) columns eluting into electron capture detectors (^H or 63^-]-) to allow multiple column peak-matching identification of fraction components. The GC columns and column conditions utilized are listed in Table 1. To facilitate peak matching, peak retention times were converted to relative retention times (relative to the retention time of p,p'-DDE) for each set of column and conditions. A file of relative retention times of many chlorinated pesticides and metabolites was compiled from chromatograms of single- and multi-component pesticide standard solutions and from retention time data reported by Thompson et^ aj_. (1969). Positions of significant peaks on chromatograms of pesticide fractions on the four columns were converted to relative retention times for comparison with the relative retention times of standards in the file. Peak identity assignments were made based on four matched relative retention times for peaks of similar height. Several pesticide and PCB fractions from silicic acid liquid chromatographic cleanup of fish extracts were examined by gas chromatography/ mass spectrometric (GC/MS) limited mass range scan techniques for DDE, dieldrin, and DDT. The fractions were chromatographed (Varian Aerograph 1400) on a 1.8 m x 4 mm ID glass column of 3% DC-200 on 60-80 mesh Gas-Chrom Q, with column and injector temperatures of 175°C and 200°C, respectively, eluting (by a helium flow of 10 ml/min) directly into the ion source of a quadrupole mass spectrometer (Finnigan 1015C) focused on narrow m/e ranges characteristic of the degradation patterns of DDE, dieldrin, or DDT. DDE ana DDT were monitored by focusing on m/e ranges of 246-250 and 235-239, respectively, adapting procedures described by Bonelli (1972). Dieldrin was detected by monitoring the m/e range of 261-267. Identities were based on the response of this selective detector consistent with appropriate retention times. Quantitative Determination For determination of DDE in fish, the 5 ml aliquots taken from extracts after florisil cleanup were diluted to 10 ml and chromatographed on a 1.5 m x 2 mm ID glass column of 3% DC-200 on 80-100 mesh Chromasorb W, and -9- ------- Table 1. GAS CHROMATOGRAPHIC COLUMNS AND CONDITIONS. Stationary Phase3 Column Length (m) Column Temperature (°C) Detector Temperature (°C) Injector Temperature (°C) Carrier Gas (Np) Flow (ml/min) 1.5% 0V- 17/1. 95% QF-1 2.1 185 210 210 15 2% OV-101/3% QF-1 1.5 150 190 210 12 1% QF-1 3 185 210 210 36 3% OV-17 2.1 185 210 210 24 aSolid support was 100-120 mesh Gas-Chrom Q. All columns are 2 mm ID coiled glass tubes. ------- eluted with N2 carrier flow of 40 ml/min into an electron capture detector (3H). The column, detector, and injector temperatures were 200, 210, and 225°C, respectively. The relatively large p,p'-DDE peak of the chromatograms allowed its determination through peak height comparison with standards. Pesticide fractions from silicic acid cleanup of fish, water, sediment, net plankton, Cladophora,and benthos extracts were chromatographed on a 3 m x 2 mm ID glass column of 1% QF-1 on 100-120 mesh Gas-Chrom Q to determine the DDT group pesticides and dieldrin. Column, detector, and injector temperatures were 180, 200, and 215°C, respectively, and the N2 flow was 30 ml/min. An electron capture detector (3H or Ni) was used. All fractions were diluted to 2 ml (with hexane) before determination except for fish extracts which were diluted to 25 ml. Areas of peaks identified as DDT group pesticides and dieldrin were measured by a disc integrator and compared with standards. Since DDE is not fractionated cleanly into the pesticide fraction during silicic acid chromatography of extracts of water ,net plankton, Cladophora.and benthos, the PCB fractions were also chromatographed as above to determine their DDE content. Sediment PCB fractions could not be similarily examined because of severe interferences. The DDE content of several fish PCB fractions from silicic acid cleanup was determined by GC/MS limited mass range scan techniques. Chromatographic conditions were similar to those described for the qualitative determination of DDE. Peak heights were compared with those of standards. PCB DETERMINATION Perchlorination PCB fractions from silicic acid cleanup of fish, water, sediment, net plankton, benthos, and Cladophora extracts were perchlorinated by procedures described by Veith (1973). Fractions were evaporated to dryness in glass vials, SbCls (0.2 ml) was added to each vial, and the vials were sealed with teflon-lined screw caps before heating to 180°C 11- ------- for 6 hr. After cooling to near 0°C in an ice bath, 1 ml of 6N_ HC1 was added to each vial to destroy the residual SbClg. The reaction solutions were extracted with five 1 ml portions of hexane. The hexane extracts were combined and passed through a disposable pipet containing anhydrous Na^SO, to remove traces of water. Some highly colored extracts from sediment PCB fractions were washed with 1 ml of 10% KOH in anhydrous methanol to remove interfering inorganics. All perchlorinated extracts were reduced to 2 ml for GC determination of decachlorobiphenyl (DCB) except fish extracts which were analyzed at 25 ml. Determination of Decachlorobiphenyl Perchlorinated PCB fractions were chromatographed on a 1.5 m x 2 mm ID glass column of 1.5% OV-17/1.95% QF-1 on 100-120 mesh Gas-Chrom Q with N9 flow rate of 50 ml/min into an electron capture detector o L-C o ( H or Ni). Column, detector, and injector temperatures were 200, 210, and 230°C, respectively. Peak heights of DCB in the extracts were compared with those of standards and the DCB content was converted numerically to equivalent concentrations of Aroclor 1254. The results of these analytical methods are reported without correction with respect to recovery during sample extraction and extract cleanup. The number of significant digits of the data reported reflects only analytical precision. Sampling precision was also considered in judge- ment of the significance of differences between sampling rates. -12- ------- SECTION V RESULTS AND DISCUSSION FISH All pesticide fractions from silicic acid cleanup of fish extracts contained DDT group pesticides and dieldrin, based on identification by multiple column GC and peak-matching techniques. In addition, several other common chlorinated hydrocarbon pesticides were identified in the extracts of fish from some sampling sites using this technique. Notably, endrin was identified in all fish taken off Prince Edward Point and from Mexico Bay, but was apparently absent in fish from a transect between Galloo Island and Stoney Island, the other eastern lake sampling site. Endrin was not identified in fish collected from western lake sites off Hamilton, Olcott, and Rochester. The BHC family pesticides were identified in fish taken off Olcott, Rochester, Prince Edward Point, and in Mexico Bay, with lindane (y BHC) generally the major constituent. Heptachlor was identified in slimy sculpin taken off Rochester. Although identity assignments from a limited file of compounds were based on peak-matching which is subject to some of the ambiquity inherent in complex chromatograms, the use of a four-column system tended to decrease the incidence of these ambiguities. The GC/MS limited mass range identity assignments of extract components provided positive identification of chlorinated hydrocarbons in fish. Using this technique, all fish pesticide fractions examined were shown to contain DDE, ODD, DDT, and dieldrin. In addition, the PCB fractions of extracts from most fish contained significant levels of DDE, while ODD, DDT, and dieldrin were undetectable (less than 2 ng/g on a whole fish basis). Concentrations of t-DDT (sum of DDT, DDE, and ODD), dieldrin, and PCBs (expressed as Aroclor 1254 equivalent) found in whole fish (i.e. wet weight basis) and the extractable fat contents of the fish are shown in Table 2. The DDE values shown resulted from preliminary DDE -13- ------- Table 2. CHLORINATED HYDROCARBONS AND FAT IN LAKE ONTARIO FISHC Species Alewi fe Alewife Alewife Alewife Alewife Alewife Smelt Smelt Smelt Smelt Smelt Slimy Sculpin Slimy Sculpin Slimy Sculpin Slimy Sculpin Slimy Sculpin Slimy Sculpin Location Hami 1 ton Olcott Rochester Mexico Bay Prince Edward Pt. Galloo-Stoney Hamilton Olcott Rochester Prince Edward Pt. Galloo-Stoney Hami Iton Olcott Rochester Mexico Bay Prince Edward Pt. Galloo-Stoney Fat Of 10 3.6 5.2 3.4 3.1 1.2 2.4 4.9 3.0 4.1 6.7 6.0 9.8 5.1 4.3 5.7 7.6 8.6 DDE 0.46 0.77 0.71 0.79 0.81 0.96 1.36 0.85 1.37 0.86 0.91 0.94 1.10 1.11 1.28 0.83 0.60 ODD 0.07 0.07 0.10 0.07 N.D. 0.08 0.06 0.05 0.13 0.10 0.10 N.D. 0.15 0.10 N.D. 0.15 0.12 DDT 0.14 0.16 0.18 0.13 N.D. 0.18 0.23 0.20 0.29 0.23 0.24 N.D. 0.29 0.26 0.26 0.25 0.17 Total DDT 1 1 n / n u/h(~i~lo "fick y y/ y wnu i c i i b r 0.67 1.00 0.99 0.99 0.81 1.22 K65 1.10 1.79 1.19 1.25 0.94 1.54 1.41 1.54 1.23 0.89 Dieldrin 0.04 0.03 0.04 0.03 0.03 0.04 0.04 0.02 0.03 0.06 0.07 N.D. 0.06 0.05 0.10 0.11 0.04 PCB 3.12 1.73 4.36 0.94 0.14 3.81 2.47 2.62 3.25 3.49 1.40 2.89 9.17 4.32 6.49 1.58 3.33 N.D. indicates that no determination was made. ------- determinations on the extracts following florisil liquid chromatographic cleanup, while the ODD and DDT levels were obtained from determinations on pesticide fractions following silicic acid cleanup. DDE was also determined on the silicic acid pesticide fractions by electron capture GC and on the silicic acid PCB fractions by limited mass range GC/MS techniques. The sum of DDE in the silicic acid pesticide and PCB fractions was considerably less than the amount in the preceding florisil eluate, in some cases as much as 50% less. However since DDE was the largest peak for chromatograms of extracts after florisil cleanup, PCB contribution to the DDE peak was probably small. In most cases, the major contribution to t-DDT values was from DDE. Quantitatively, DDT and ODD were minor constituents, making up less than 26% and 14% of the total, respectively. Although dieldrin concentrations shown (Table 2) are of interest, the low levels observed do not allow evaluation of possible station-to-station or species-to-species relationships. The higher levels of t-DDT observed provide a better basis for comparisons. Individual variation in the chlorinated hydrocarbon contents of the fish were decreased by sampling an aggregate of ground whole fish of several age-weight classes for each species collected at each site. Because chlorinated hydrocarbon levels have been related to the fat content of the fish (Veith, 1973), these variations likely are further decreased by examining chlorinated hydrocarbon concentrations in relation to the extractable fats contents of the whole fish. Table 3 shows t-DDT and PCB levels in fish based on fat content. This data indicates that the more migratory alewives and smelt accumulate higher t-DDT levels on a fat basis (averages of 36.2 yg/g and 30.5 yg/g) than the less migratory slimy sculpin (16.9 yg/g) (Scott and Grossman, 1973). Relative standard deviations for t-DDT levels (fat basis) for the species are 53, 36, and 66% for alewives, smelt, and slimy sculpin, respectively. Comparison of these variations with the average relative deviation for analytical replicates for extracts of an aggregated sample (14%) suggests that these variations are partly related to differences in chlorinated hydrocarbon levels among the sampling sites. -15- ------- Table 3. DDT AND PCBs IN LAKE ONTARIO FISH FAT (yg/g) Species Alewife Alewife Alewife Alewife Alewife Alewife Smelt Smelt Smelt Smelt Smelt Slimy Sculpin Slimy Sculpin Slimy Sculpin Slimy Sculpin Slimy Sculpin Slimy Sculpin Location Hami 1 ton Olcott Rochester Mexico Bay Prince Edward Pt. Galloo-Stoney Hamilton Olcott Rochester Prince Edward Pt. Galloo-Stoney Hami 1 ton Olcott Rochester Mexico Bay Prince Edward Pt. Gal loo-Stoney Total DDT 18.6 19.2 29.1 31.9 67.5 50.8 33.7 36.7 43.7 17.8 20.8 9.6 30.2 32.8 27.0 16.2 10.4 PCB PCB/Total DDT 86.7 33.3 128.2 30.3 11.7 158.8 50.4 87.3 79.3 52.1 23.3 29.5 179.8 100.5 113.9 60.3 38.7 4.7 1.7 4.4 0.9 0.2 3.1 1.5 2.4 1.8 2.9 1.1 3.1 6.0 3.1 4.2 3.7 3.7 -16- ------- This is supported by the highest relative standard deviation for the slimy sculpin. Considering the slimy sculpin data shown in Table 3, the waters off Olcott, Rochester, and of Mexico Bay may contribute to greater accumulaion of DDT group pesticides by slimy sculpin than water off Hamilton, Prince Edward Point, and between Galloo and Stoney Islands. The lake bottom characteristics of these areas may also be important factors in the chlorinated hydrocarbon accumulation in the bottom-feeding sculpin. The lake-wide average for t-DDT (whole fish) in smelt (1.40 yg/g) for 1972 compares favorably with that reported by Reinert (1970) for Lake Ontario fish captured from 1965 to 1968 (1.58 yg/g) although the alewife value (0.95 yg/g) is less than half that reported in 1970 (1.99 yg/g). Reinert (1970) did not report on Lake Ontario slimy sculpin. Dieldrin levels reported by Reinert (1970) for alewives and smelt caputred from 1967 to 1968 (0.11 yg/g and 0.06 yg/g, respectively) are comparable to levels in fish for 1972 (0.04 yg/g for alewife and smelt). PCB concentrations (2.65 yg/g) found in smelt (Table 2) were similar to those reported by Veith (1973) for Lake Michigan smelt (2.7 yg/g). However, concentrations found in alewives (2.35 yg/g) were considerably lower than values reported for Lake Michigan alewives (4.6 yg/g). For both lakes, PCB levels were expressed as Arochlor 1254 equivalent. Slimy sculpin were not included in the Lake Michigan report. Lake Ontario slimy sculpin exhibited highly variable PCB and t-DDT concentrations on a fat basis. The relative standard deviation for PCB levels in slimy sculpin (fat basis) was 65% about a mean of 97.1 yg/g. Corresponding relative standard deviation values for alewives and smelt were about 80% (mean = 74.8 yg/g) and 44% (mean = 58.5 yg/g), respectively. This indicates greater station-to-station variation for PCB accumulation in slimy sculpin and alewives than in smelt. Furthermore, the waters near Olcott, Rochester and in Mexico Bay contributed to greater accumulation of PCB concentrations by sculpin than waters off Hamilton, -17- ------- Prince Edward Point, and between Gal loo and Stoney Islands, which is in agreement with the trend for DDT accumulation. A large variation was observed in PCB/t-DDT ratios for fish (Table 3). Average values, however, (2.5 for alewives, 1.9 for smelt, and 4.0 for slimy sculpin), were comparable to those reported by Veith (1973) (1.4 for alewives and 2.6 for smelt) for Lake Michigan fish. PCB/t-DDT ratios were often cited due to chemical similarities between PCBs and persistent DDT metabolites, although their importance has not been well established. WATER The t-DDT, dieldrin, and PCB concentrations for water are shown in Table 4. Since there were no apparent relationships between concentra- tions and depth, with the one exception as discussed below, determinations from different depths were treated as replicates for each site and averaged. Lake-wide averages for t-DDT and dieldrin were 28 ng/1 and 4.8 ng/1, respectively. Relative standard deviations for t-DDT and dieldrin were 54% and 85%, respectively, indicating considerable site-to-site variation. Waters off Hamilton, Cobourg, and Oswego showed high levels of t-DDT. Dieldrin levels were highest off Cobourg and Oswego. The anomalously high dieldrin level for waters of Oswego resulted from a very high surface water value (34.9 ng/1) which was averaged with a much lower levels found in samples of deeper waters (1.7 ng/1 and 1.1 ng/1). In all waters, except off Oswego, DDE was the major component of the DDT group pesticides. ODD contributed 0 to 19%, while DDT represented 6 to 13% in most cases. The t-DDT in waters off Oswego contained higher proportions of ODD and DDT, 28% and 26%, respectively. Waters from the Deep Hole area of the Rochester Basin showed a t-DDT level of 16 ng/1 with DDT contributing over 40%. -18- ------- Table 4. CHLORINATED HYDROCARBONS IN LAKE ONTARIO WATER (ng/1) Location Hami 1 ton Toronto Niagara River Olcott Cobourg Rochester Deep Hole Oswego IFYGL Station Identifier 1 8 13 30 36 60 75 90 Station Depth m 33 76 13 24 24 25 229 21 DDE 37.4 20.5 13.9 26.6 45.2 29.9 9.4 22.4 ODD 2.5 1.6 0.9 7.1 4.5 < 0.5 < 0.5 13.8 DDT 4.5 1.4 2.4 4.6 7.2 2.3 6.5 12.8 Total DDT 44 24 17 38 57 32 16 49 Dieldrin 3.1 3.5 2.1 3.9 9.9 2.2 1.3 12.6 PCB 49 35 97 44 45 40 56 77 ------- PCB concentrations for Lake Ontario waters were between 35 and 56 ng/1, except for waters off Oswego (77 ng/1) and the mouth of the Niagara River (97 ng/1). The lake-wide average concentration was 55 ng/1. Neglecting the two highest concentrations, the lake-wide average becomes 45 ng/1 with a relative standard deviation of 16%. Other than these south-shore areas, the PCB content of Lake Ontario waters appears relatively uniform. The PCB/t-DDT ratios for Lake Ontario waters averaged 2.1, a value comparable to that for Lake Ontario fish. Since the water sampling and extraction procedures did not discriminate between dissolved and particulate fractions, the t-DDT, dieldrin, and PCB concentrations shown in Table 4 represent "total" concentrations. The contribution of contaminants associated with net plankton (i.e., particles larger than 64 urn) to the "total" levels found in Lake Ontario waters is estimated to be less than 1%. This estimate was calculated from the contaminant concentrations found in net plankton (Table 6) from three areas of Lake Ontario, phytoplankton cell counts determined for these areas during the month these areas were sampled for chlorinated hydrocarbons (Stoermer, 1973), and dry weight per cell values reported for a laboratory algal culture (Lee et_aj_., 1971). Thus DDT group pesticides, dieldrin, and PCBs in the Lake Ontario waters sampled are likely dissolved or associated with particles that will pass through a 64 urn net (e.g., nanoplankton and small inorganic particles). SEDIMENT Sediment concentrations of t-DDT, dieldrin, and PCBs are shown in Table 5. Lake-wide averages for sediment t-DDT and dieldrin are 22 ng/g and 1.2 ng/g, respectively, with relative standard deviations of 72% and 61%, respectively. These variations are indicative of significant site-to-site differences. Sediments taken off the mouth of the Well and Canal and at the eastern mid-lake site showed higher levels of dieldrin and t-DDT. Sediment from three of the eight sites showed DDE contributions to t-DDT levels of less than 50%. ODD was the major contributor to t-DDT -20- ------- Table 5. CHLORINATED HYDROCARBONS IN LAKE ONTARIO SEDIMENT (ng/g dry sediment)3 Location Wei land Canal Niagara River Olcott Cobourg Mid- lake Rochester Oswego Mid-lake East IFYGL Station Identifier 12 13 30 36 46 60 91 93 DDE 12 11 4.8 8.0 11 8.0 9.0 16 ODD 15 3.5 5.6 0.9 5.4 1.5 5.1 31 DDT 12 0.7 1.2 0.9 2.8 0.2 3.8 7.4 Total DDT 39 15 12 10 19 10 18 54 Dieldrin 2.6 1.4 0.9 0.6 0.5 0.9 0.8 2.1 PCB 245 155 80 43 79 84 158 N.D. J.D. indicates no determination was made. ------- in sediments from the eastern mid-lake site and off the Well and Canal. The DDE levels shown in Table 5 must be considered underestimates, however, since it was not possible to measure the DDE contents of sediment PCB fractions due to interferences. Lake-wide t-DDT and dieldrin averages were comparable generally to those found by Leland et al_. (1973) for southern Lake Michigan top interval sediments (18.5 ng/g and 2.0 ng/g, respectively). However, the Lake Michigan sediments showed major DDT contributions (ca. 50%) to the t-DDT, while Lake Ontario data showed DDT contributions no greater than 31%. Sediment PCB concentrations averaged 120 ng/g. PCB concentrations in sediments off the mouths of the Welland Canal and Niagara River and off Oswego, (mean = 184 ng/g) averaged more than twic the concentrations found at the four other sites (mean = 72 ng/g). Considering the high PCB contents found for lake water off the mouth of the Niagara River and off Oswego, the Niagara and Oswego Rivers may be important sources to Lake Ontario of PCBs associated with settlable particulates. The PCB/t-DDT ratios exhibited a low relative standard deviation of 33% about a mean of 7.0. This mean may be too high due to underestimation of DDE levels. It is unlikely, however, that the DDE content of the sediment extracts could be great enough to decrease PCB/t-DDT ratios to levels similar to those for the fish and water. NET PLANKTON DDT group pesticides, dieldrin, and PCB levels (dry weight basis) found in mixed net plankton are shown in Table 6. Although the samples were predominantly viable phytoplankton, the sampling method also collects smaller zooplankton, detritus, and suspended inorganic matter. Contributions of these minor components could not be assessed. Lake-wide averages for t-DDT and dieldrin were 3.5 yg/g and 0.12 yg/g on a dry weight basis, respectively, with corresponding relative standard deviations of 42% and 91%. In nearly every case, DDE comprised over 75% of the t-DDT concentrations. -22- ------- Table 6. CHLORINATED HYDROCARBONS IN LAKE ONTARIO NET PLANKTON \a (yg/g dry weight)' GO i Location Hamilton Mid-lake West Cobourg Mid-lake Rochester Deep Hole Mid-lake East IFYGL Station Identifier 1 10 36 45 60 75 96 DDE 4.00 3.52 3.26 1.49 1.19 5.89 2.45 ODD 0.09 0.37 < 0.05 0.07 < 0.05 0.04 0.09 DDT 0.04 0.12 < 0.05 0.78 < 0.05 < 0.05 0.86 Total DDT 4.1 4.0 3.3 2.3 1.2 5.9 3.4 Dieldrin 0.24 0.25 < 0.05 0.16 0.02 0.02 0.18 P'CB 3.4 10.6 7.6 3.6 N.D. 11.8 6.0 N.D. indicates that no determination was made. ------- Net plankton PCB levels averaged 7.2 yg/g. Plankton from the Deep Hole of the Rochester Basin and the mid-lake west site, show high PCB levels contributing to a relative standard deviation of 49% for the lake-wide average PCB concentration. The average PCB/t-DDT ratio (3.1) was somewhat higher than for water or fish. Chlorinated hydrocarbon levels for plankton appeared high compared to concentrations in fish. However, plankton concentrations were expressed on a dry weight basis while fish concentrations were on a whole fish (wet weight) basis. Assuming whole fish are about 20% dry weight (F.D.A., 1969), typical fish t-DDT, dieldrin, and PCB concentrations were 7.0 yg/g, 0.3 yg/g, and 13.2 yg/g dry weight (smelt), respectively. On this basis, net plankton concentrations of these chlorinated hydrocarbons were about 50% less than concentrations in fish. CLADOPHQRA The results of determinations of DDT group pesticides, dieldrin, and PCB levels in extracts of Cladophora are shown in Table 7. Most samples, except those off Toronto and in the Black River Bay, were from the south shore of Lake Ontario. The exact sampling site locations of four of the samples is uncertain. The average t-DDT, dieldrin, and PCB levels (dry weight basis) were 229, 13, and 515 ng/g, respectively, with relative standard deviations of 40, 64, and 39%, respectively. These concentrations are 10 to 100 times less than for net plankton. The average PCB/t-DDT ratio of 2.3 was near the corresponding averages for fish and water. BENTHOS DDT group pesticide, dieldrin, and PCB levels determined for extracts of benthic fauna, largely Pontiporeia, are shown in Table 8. Of the three samples taken, one off Hamilton showed t-DDT, dieldrin, and PCB levels approximately four times those determined for benthos off Oswego and Rochester. Also, ODD made a significantly larger contribution to the t-DDT in benthos off Rochester than other samples. Average t-DDT and PCB levels, 99 ng/g and 471 ng/g on a dry weight basis, respectively, -24- ------- Table 7. CHLORINATED HYDROCARBONS IN LAKE ONTARIO CLADOPHORA (ng/g dry weight) Location Black River Bay Black River Bay South Shore3 South Shore9 South Shore9 South Shore9 Rochester Toronto aSpecific sampling DDE 344 129 97 194 347 192 165 196 site Table 8. CHLORINATED Location Hamilton Rochester Oswego DDE 124 34 26 ODD 4.8 0.45 19 26 17 30 5.2 13 unknown. DDT 7.4 1.9 2.5 4.7 1.1 16 6.0 8.0 HYDROCARBONS IN (ng/g dry ODD 26 1.8 3.4 weight) DDT 59 6.1 2.4 Total DDT 357 131 119 225 365 238 176 217 LAKE ONTARIO Total DDT 209 42 32 Dieldrin 1.9 6.5 14 14 4.0 25 16 21 BENTHIC FAUNA Dieldrin 14.8 2.9 3.0 PCB 860 333 232 607 436 576 411 666 PCB 976 341 97 -25- ------- were quite comparable to levels reported by Flotard (1974) for Pontiporela of the western shore of Lake Michigan, 130 ng/g and 310 ng/g, respectively. The PCB/t-DDT ratios averaged 5.3. This value is somewhat higher than that calculated from the concentrations reported by Flotard (1974) or ratios calculated for all other samples reported except sediment. Although some sediment contamination may be indicated, the benthos PCB/t-DDT ratio is comparable to that for slimy sculpin (4.0), whose diet is primarily benthic fauna (Scott and Grossman, 1973). -26- ------- SECTION VI REFERENCES BoneTli, E.J. 1972. Gas Chromatograph/Mass Spectrometer Techniques for Determination of Interferences in Pesticide Analysis. Anal. Chem. 44:603-606. Flotard, R.D. 1974. PCBs in Lake Sediments. Ph.D. Thesis (Water Chemistry), University of Wisconsin, Madison (in progress). Kaiser, K.L.E. 1974. Mirex: An Unrecognized Contaminant of Fishes from Lake Ontario. Science 185:523-525. Lee, C.C., R.F. Harris, J.K. Syers, and D.E. Armstrong. 1971. Adenosine Triphosphate Content of Selenastrum capricornutum. Appl. Microbiol. 21:957-958. Leland, H.V., W.N. Bruce, and N.F. Shimp. 1973. Chlorinated Hydrocarbon Insecticides in Sediments of Southern Lake Michigan. Environ. Sci. Technol. 7:833-838. Reinert, R.E. 1970. Pesticide Concentrations in Great Lakes Fish. Pestic. Monit. J. 3:233-240. Scott, W.B. and E.J. Crossman. 1973. Freshwater Fishes of Canada. Fish. Res. Bd. Can. Bulletin 184, Ottawa. 966 p. Stoermer, E.F. 1973. Analysis of Phytoplankton Composition and Abundance During IFYGL. In: First Annual Reports of EPA Grants Funded for IFYGL. Ecol. Res. Series #EPA-660/3-73-021. U.S. Environmental Protection Agency, Grosse He Laboratory, Grosse He, Michigan, pp. 90-109. Thompson, J.F., A.C. Walker, and R.F. Moseman. 1969. Evaluation of Eight Gas Chromatographic Columns for Chlorinated Pesticides. J.A.O.A.C. 52:1263-1277. U.S. Food and Drug Administration. 1969. Pesticide Analytical Manual, Volume 1. U.S. Department of Health, Education and Welfare, Washington, D.C. -27- ------- Uthe, J.F., J. Reinke, and H. Gesser. 1972. Extraction of Organochlorine Pesticides from Water by Porous Polyurethane Coated with Selective Absorbent. Environ. Letters 3:117-135. Veith, G.D. 1970. Environmental Chemistry of PCBs in the Milwaukee River. Ph.D. Thesis (Water Chemistry), University of Wisconsin, Madison. 180 p. Veith, G.D. 1973. Chlorinated Hydrocarbons in Fish from Lake Michigan. A final report on Project #16020PBE to the U.S. Environmental Protection Agency, National Water Quality Laboratory, Duluth, Minnesota. University of Wisconsin-Madison, Water Chemistry Department, Madison, Wisconsin. 129 p. -28- ------- TECHNICAL REPORT DATA (Please read Instructions on the reverse before completing) 1. REPORT NO. EPA-660/3-75-022 3. RECIPIENT'S ACCESSI Of* NO. 4. TITLE AND SUBTITLE 5. REPORT DATE Chlorinated Hydrocarbons in the Lake Ontario Ecosystem. 6. PERFORMING ORGANIZATION CODE 7. AUTHOR(S) C.L. Haile, G.D. Veith*, G.F. Lee*, W.C. Boyle *NWQL, Duluth, Minn.; **Univ. of Texas - Dallas 8. PERFORMING ORGANIZATION REPORT NO. 9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT NO. Water Chemistry Program University of Wisconsin Madison, Wisconsin 11. CONTRACT/GRANT NO. R-800608 12. SPONSORING AGENCY NAME AND ADDRESS Environmental Protection Agency 13. TYPE OF REPORT AND PERIOD COVERED Final Report 14. SPONSORING AGENCY CODE 15. SUPPLEMENTARY NOTES 16. ABSTRACT Lake Ontario fish, water, sediment, net plankton, Cladophora, and benthos were examined for DDT group pesticides, dieldrin, and PCBs. Endrin, BHC group pesticides, and heptachlor were also identified in some fish samples. Average concentrations ranged from 28 ng/1 (t-DDT), 4.8 ng/1 (dieldrin), and 55 ng/1 (PCBs as Aroclor 1254 equivalent) for water to 1.40 yg/g (t-DDT), 0.07 yg/g (dieldrin), and 5.15 yg/g (PCBs) for whole fish. DDE levels were generally similar to t-DDT levels, except for sediments where ODD and DDT contributed significantly to t-DDT values. PCB/t-DDT ratios averaged 2.6 for all samples except for sediment (7.0) and benthos (5.3). KEY WORDS AND DOCUMENT ANALYSIS DESCRIPTORS b.IDENTIFIERS/OPEN ENDED TERMS c. COSATI Field/Group PCBs DDT Dieldrin Biota Water Sediment Lake Ontario 3. DISTRIBUTION STATEMENT Release Unlimited 19. SECURITY CLASS (This Report) 21. NO. OF PAGES 20. SECURITY CLASS (This page) 22. PRICE EPA Form 2220-1 (9-73) * U.S. GOVERNMENT PRINTING OFFICE: I975-698-638 /I62 REGION 10 ------- |