N S T I T U T E RTI/1864/50-03 F December 7, 1982 Final Report POLYCHLORINATED BIPHENYLS IN THE ENVIRONMENT AND FRESHWATER FISH by R. M. Lucas V, G. lannacchione D. K. Melroy Research Triangle Institute Research Triangle Park North Carolina 27709 2PA Contract Number: 68-01-5848 Project Officer: Joseph Carra Task Manager: Richard Levy U.S. Environmental Protection Agency Office of Toxic Substances Exposure Evaluation Division Design and Development Branch 401 M Street, S.W. Washington, D.C. 20460 RESEARCH TRIANGLE PARK, NORTH CAROLINA 27709 ------- This report was prepared under contract to an agency of the United States Government. Neither the United States Government nor any of its employees, contractors, subcontractors, or their employees makes any warranty, expressed or implied, or assumes any legal liability or responsibility for any third party's use or the results of such use of any information, apparatus, product, or process disclosed in this report, or represents that its use by such third party would not infringe on privately owned rights. Publication of the data in this document does not signify that the contents necessarily reflect the joint or separate views and policies of each sponsoring agency. Mention of trade names or commercial products does not constitute endorsement or recommendation for use. ------- RTI/1864/50-03 F December 7, 1982 Final Report POLYCHLORINATED BIPHENYLS IN THE ENVIRONMENT AND FRESHWATER FISH by R. M. Lucas V. 6. lannacchione D. K. Melroy Research Triangle Institute Research Triangle Park North Carolina 27709 EPA Contract Number: 68-01-5848 Project Officer: Joseph Carra Task Manager: Richard Levy U.S. Environmental Protection Agency Office of Toxic Substances Exposure Evaluation Division Design and Development Branch 401 M Street, S.W. Washington, D.C. 20460 Approved by: Robert M. Lucas, Task Leader Research Triangle Institute Stephen R. Williams, Project Leader Research Triangle Institute ------- Table of Contents 1. EXECUTIVE SUMMARY 1 2. INTRODUCTION 2 3. ENVIRONMENTAL DATA SUMMARY 3 3.1 Urban Soils Monitoring Network 3 3.1.1 General Description of the Network 3 3.1.2 Historical Uses of the Network 3 3.1.3 Limitations as a Monitoring Network 3 3.1.4 Overview of Network Designs 3 3.1.5 Summary of Polychloriaated Biphenyl Data . . 4 3.2 Rural Soil Monitoring Network 4 3.2.1 General Description of the Network 4 3.2.2 Overview of Sample Design 4 3.2.3 Limitations of the Network 8 3.2.4 Summary of Polychlorinated Biphenyl Data from the Network 8 3.3 National Surface Water Monitoring Program 9 3.3.1 General Description of the Monitoring Program 5 3.3.2 Limitations of Statistical Inferences. ... 9 3.3.3 Summary of Polychlorinated Biphenyl Data . . 9 4. POLYCHLORINATED BIPHENYLS IN FRESHWATER FISH 16 4.1 General Description of the Study 16 4.2 Overview of the Study Design 16 4.3 Statistical Limitation of Data 16 4.4 Summary of Polychlorinated Biphenyls in Freshwater Fish Data l6 5. SUMMARY AND CONCLUSIONS 19 5.1 Introduction 1^ 5.2 Comparisons Among Media 19 6. REFERENCES 21 ------- List of Tables Table Page 3.1 Summary of Sample Sizes and Percent of Detections of Polychlorinated Biphenyls by Calendar Year and Medium for the Urban Soil Monitoring Network 5 3.2 Summary of Positive Values of Polychlorinated Biphenyls by Calendar Year and Type of Lawn Soil 6 3.3 Summary of Positive Values of Polychlorinated Biphenyls by Calendar Year and Type of Waste Soil 7 3.4 Summary of Polychlorinated Biphenyl Data Collected from Cropland Areas of the Rural Soil Monitoring Network . . 10 3.5 Summary of the Prevalence of Polychlorinated Biphenyls in Surface Water 12 3.6 Summary of the Prevalence of Polychlorinated Biphenyls in Bottom Sediment 13 3.7 Summary of the Prevalence of Polychlorinated Biphenyls in Bottom Sediment 14 3.8 Summary of Positive Values of Polychlorinated Biphenyls in Bottom Sediment • 15 4.1 Summary of Polychlorinated Biphenyls in Freshwater Fish 17 List of Figures Figure Page 5.1 Diagram of Collection Time Periods of Polychlorinated Biphenyl Data by Media 20 ------- ACKNOWLEDGEMENTS The authors would like to thank the Task Manager, Mr. Richard Levy for his assistance and direction in producing this report. The authors would also like to thank Mr. Anthony Inglis, Ms. Ann Carey and Mr. Daniel Heggem of the Field Studies Branch, Exposure Evaluation Division, for thier assistance and comments in completing this document. The authors also thank Ms. Martha Clegg for her fine efforts in typing this manuscript. ------- 1. EXECUTIVE SUMMARY This report gives a summary of the prevalence and levels of poly- chlorinated biphenyls (PCBs) in fresh water fish and the environment. Data collected from the Urban Soil Network, the Rural Soil Network, and the National Surface Water Monitoring Program are reviewed and summarized. Additional materials on PCBs in freshwater fish supplied to the U.S. Environmental Protection Agency by the U.S. Department of the Interior (USDI) are also included. The percent of specimens with detectable amount of PCS residue in urban and suburban soil ranged from 0.0 percent in 1970 to over 10 percent in 1978, and averaged 3.3 percent during that period. Only 2 of 7,664 specimens of rural soils were found to contain detectable levels of PCB residue. The percent of surface water specimens with detectable amounts of PCB varied greatly with a maximum of 35.5 percent in the spring quarter of 1975 and a minimum of 0.0 in many other quarters. The percent detected in bottom sediment ranged from over 50 percent during the spring quarter of 1975 to 8.1 percent in the fall quarter of 1979. The percent detected appears to decline from 1975 to 1980 in both water and sediment data. The levels of PCBs in water and sediment in which detected values were noted vary widely from year to year and within the year, but do not exhibit any apparent trends or patterns. The levels found in sediment tend to be at least a factor of 10 higher than the levels found in surface water. The percentage in tissue specimens from freshwater fish with detect- able levels of PCBs increases from 91.5 percent in 1976-1977 to 98.1 percent in 1978-1979. -1- ------- 2. INTRODUCTION This report presents a concise summary of the prevalence and levels of polychlorinated biphenyls (PCBs) in several environmental media. The primary sources for this report are previously prepared preliminary reports on the U.S. Environmental Protection Agency's (US EPA) monitoring programs for water, water sediment, soil, and their computer accessible data files. Additional materials provided by the US EPA are also included as sources. Chapter three deals with PCBs in the environment. The first two sections describe PCB residue levels found in soil collected in the US EPA's National Soil Monitoring Program. Section one describes and presents results from the Urban Soils Network, and section two relates to the Rural Soils Network. Section three summarizes information on PCBs found in surface water and bottom sediment collected in the National Surface Water Monitoring Program. Chapter four summarizes PCB levels found in fresh water fish based on unpublished information provided to the US EPA by the USDI. Chapter five gives a concise overview of the PCB data and points out similarities and differences among the various media investigated. Chapter six includes a list of all documents refer- enced in the report. In order to limit the amount of material presented, only brief descriptions of the monitoring programs and studies and their survey design are given. The reader is advised of potential limitations in making inferences beyond the sample data. References are included for the reader interested in more detail. Several terms that have rigorous statistical definitions are used in the report. Below are nontechnical definitions for these terms. Target Population; The universe to which an investigator wishes to make inferences. Examples are the civilian population in the U.S. or all rural soils in the U.S. to a depth of three inches, as of a specific point in time. Sampling Frame: A list or inventory of the entire universe to be sampled. Examples are a list of all counties in the U.S., or a conceptualized list of all 3 inch cubes of top-soil in the U.S. Probability Sampling; A process by which each unit on a sampling frame may be selected for study with a known and positive probability. -2- ------- 3. ENVIRONMENTAL DATA SUMMARY 3.1 Urban Soils Monitoring Network 3.1.1 General Description of the Network The National Soil Monitoring Program consists of two networks: the Urban Soils Monitoring Network (USMN) and the Rural Soils Monitoring Network. Areas considered to be urban in character are monitored by the Urban Soils Monitoring Network. Over the past twelve years such monitoring efforts have been undertaken in 42 cities and Standard Metropolitan Statistical Areas (SMSAs). Between 5 and 14 cities were sampled each year between 1969 (FY70) and 1979 (FY80), each city being resampled every six years with the second cycle starting in 1975 (FY76). Residues of thirteen pesticides and polychlorinated bi- phenyls (PCBs) were detected in the associated urban soil samples, and in addition, residue levels of three metals were measured. A listing of the pesticide residue and metals is given in a USMN report (McDonald 1981). A description of the chemical analysis method is given in Whitmore et al. (1980). This section presents a concise summary of the residue levels for 1970 through 1978. 3.1.2 Historical Uses of the Network The major historical objectives of the Urban Soils Monitoring Network (USMN) were to monitor pesticide residue in urban areas for prevalence, levels, and trends over time. 3.1.3 Limitations as a Monitoring Network The Urban Soils Monitoring Network has not yet been used to its fullest potential as a monitoring network. Because Urban Soils sampling has not been based on a strict probability structure (McDonald, 1981), inferences about residue levels for urban areas in general at the national or regional level have limited defensibility and are of unknown accuracy. Because of the above mentioned inferential limitations, the PCBs summaries presented below relate only to the sampled cities. 3.1.4 Overview of Network Designs The Urban Soils Monitoring Network has monitored four classes of compounds in urban soils: organochlorine pesticides and PCBs, trifluralin, organophosphorus pesticides, and heavy metals. Forty-two urban areas across the United States have been monitored on a rotating basis since 1969. Two different sample designs were tried experimentally in 1969 and 1970, and a third sample design was imple- mented in 1971 to be used in all subsequent years. These sample designs are described in detail in the NSMP report (Whitmore et al, 1981). The first two sample designs each had a single stage of stratification with three stages of selection: cities, grid units (land areas of fixed and equal size), and sample sites. Stratification in 1969 was based on geo- graphic regions, and in 1970 was based on the population size of the urban areas. Soil specimens were collected from 400 sites in 8 cities in 1969 and from 356 sites in 14 cities in 1970. -3- ------- For 1971 through 1975, the sampling frame used was the list of 243 SMSAs in the United States, as defined in the 1970 U.S. Census. Two stages of stratification were used: size of population at the first stage and, at the second stage, sample SMSAs were stratified into urban and suburban areas. Sites were selected at a rate of one site per square mile (2.6 km2) in the urban stratum, and one site per 20 square miles (51.8 km2) in the suburban stratum. 3.1.5 Summary of Polychlorinated Biphenyl Data Data for 1970 through 1978 are available in computer accessable form. The sample sites are classified into one of four categories (Whitmore et al 1980): (i) urban lawn soil, (ii) urban waste soil, (iii) suburban lawn soil, and (iv) suburban waste soil. Table 3.1 presents the number of soil specimens collected by category and year where PCBs were measured and the percentage of the specimens that con- tained positive amounts of PCBs. For years in which specimens were collected from both soil categories and both waste categories, the data are combined to give an overall estimate. Because the percentages detected are very low, additional summari- zation seems of little use. Table 3.2 presents number of positive PCB values recorded in lawn soil, and the minimum and maximum of those values by year. Table 3.3 contains the same summary format for waste soil. These data are not indicative of a ubiquitous presence of PCBs in the categories. Among the maximum positive values, only two are over 10 ppm. One is 60.80 ppm from suburban lawn soil in 1973, and the other is 11.94 ppm from urban waste soil in 1971. 3.2 Rural Soil Monitoring Network 3.2.1 General Description of the Network The Rural Soils Monitoring Network (RSMN) is the second component of the National Soil Monitoring Program and was intended to monitor all soil in the conterminous United States except in areas considered to be urban in character. The urban areas are included in the scope of the USMN discussed in the previous section. Because the RSMN is a probability sample of rural soils, valid generalizations about all rural soils in the conterminous United States and other reasonably large geographic areas are possible with some limitations discussed below. 3.2.2 Overview of Sample Design A detailed description of the RSMN survey design, compounds targeted for chemical analysis, and evaluation of the chemical analysis methods are given in the NSMP report (Whitmore et al, 1981). Only a brief overview is given below. The Rural Soil Network (RSN) is a probability sample of 10-acre sites from the population of all rural land areas in the conterminous United States. Each 10-acre site is located by a probability subsample -4- ------- Table 3.1 Summary of Sample Sizes and Percent Detections of Polychlorinated Biphenyls by Calendar Year and Medium for the Urban Soil Monitoring Network* Medium Urban Lawn Soil Urban Waste Soil Urban (Combined) Suburban Lawn Soil Suburban Waste Soil Suburban (Combined) Urban Lawn Soil Urban Waste Soil Urban (Combined) Suburban Lawn Soil Suburban Waste Soil Suburban (Combined) Sample Size 163 137 300 0 0 0 Sample Size 245 122 367 0 0 0 1970 Percent Detected 0.0 0.0 0.0 NA NA NA 1975 Percent Detected 2.9 4.9 3.6 NA NA NA Sample Size 104 42 146 40 137 177 Sample Size 199 144 343 0 0 0 1971 Percent Detected 1.9 7.1 4.7 2.5 1.5 1.7 1976 Percent Detected 8.0 9.0 8.4 NA NA NA Sample Size 73 88 161 67 203 270 Sample Size 79 73 152 20 43 63 1972 Percent Detected 1.4 3.4 2.5 1.5 0.5 0.7 1977 Percent Detected 6.3 4.1 5.2 0.0 0.0 0.0 Sample Size 114 89 203 76 156 232 Sample Size 39 64 103 54 188 242 1973 Percent Detected 3.5 3.4 3.5 3.9 0.6 1.7 1978 Percent Detected 10.3 3.1 5.8 0.0 0.5 0.4 1974 Sample Size 82 82 164 110 172 282 All Sample Size 1105 901 2006 367 898 1265 Percent Detected 2.4 7.3 4.9 2.7 1.2 1.8 Years Percent Detected 3.7 4.3 4.0 2.2 0.8 1.2 NA: Calculation is not applicable with available data. * Source: Calculated by the Research Triangle Institute with data collected from the Urban Soils Monitoring Network sponsored by the U.S. Environmental Protection Agency. ------- Table 3.2 Summary of Positive Values of Polychlorinated Biphenyls by Calendar Year and Type of Lawn Soil* Calendar Year 1970 1971 1972 1973 1974 1975 1976 1977 1978 Type of Lawn Soil Urban Suburban Urban Suburban Urban Suburban Urban Suburban Urban Suburban Urban Suburban Urban Suburban Urban Suburban Urban Suburban Sample Size 163 0 104 40 73 67 114 76 82 110 245 0 199 0 79 20 39 0 Number of Positive Values 0 NA 2 1 1 1 4 3 2 3 7 NA 16 NA 5 0 4 NA Minimum Positive Value (ppm)** NA NA 0.20 0.26 1.01 0.94 0.40 0.21 1.08 0.50 0.04 NA 0.04 NA 0.04 NA 0.10 NA Maximum Positive Value (ppm)** NA NA 3.30 0.26 1.01 0.94 1.59 60.80 1.70 1.00 0.67 NA 2.62 NA 4.52 NA 0.81 NA NA: Calculation is not applicable with available data. * Source: Calculated by the Research Triangle Institute with data collected from the Urban Soils Monitoring Network of EPA. ** parts per million -6- ------- Table 3.3 Summary of Positive Values of Polychlorinated Biphenyls by Calendar Year and Type of Waste Soil* Calendar Year 1970 1971 1972 1973 1974 1975 1976 1977 1978 Type of Waste Soil Urban Suburban Urban Suburban Urban Suburban Urban Suburban Urban Suburban Urban Suburban Urban Suburban Urban Suburban Urban Suburban Sample Size 137 0 42 137 86 203 89 156 82 172 122 0 144 0 73 43 64 188 Number of Positive Values 0 NA 3 2 3 1 3 1 6 2 6 NA 13 NA 3 0 2 1 Minimum Positive Value (ppm)** NA NA 0.70 0.09 0.34 1.31 0.18 0.61 0.39 0.40 0.03 NA 0.03 NA 0.08 NA 1.65 0.08 Maximum Positive Value (ppm)** NA NA 11.94 0.36 1.31 1.31 0.63 0.61 3.33 0.97 0.36 NA 1.87 NA 0.09 NA 7.81 0.08 NA: Calculation is not applicable with available data. *Source: Calculated by the Research Triangle Institute with data collected from the Urban Soils Monitoring Network of EPA. ** parts per million -7- ------- of the data points of the 1967 Conservation Needs Inventory (CNI) (USDA 1966). The CNI, in turn, is a probability sample of all rural land areas (USDA 1966) in the conterminous United States. The CNI is a stratified random sample of primary sampling units (PSUs) from each county of the conterminous United States, except for those counties strictly metropolitan in character. The standard size of the PSUs was 160 acres, although 40-acre, 100-acre, and 640-acre PSUs were not uncommon. The standard sampling rate was two percent, however this rate was increased or decreased in order either to provide esti- mates of nearly equal precision for all counties or to oversample areas of special interest. The sampling rates varied within strata from less than one percent to approximately thirty-two percent. Data were collected for each of a series of points at every CNI sample site. The land-use data collected for each CNI sampling point was used to classify the point as either a cropland point or a non- cropland point. The sampling design of the RSMN specified that 0.025 percent of the cropland and 0.0025 percent of the noncropland of the rural conterminous United States would be sampled from each State. A subsample of the CNI cropland sampling points was selected and used to locate the RSMN cropland sample sites. The RSMN noncropland sample sites were located by a subsample of the CNI noncropland sampling points. The operational design of the RSMN specified that each cropland site be randomly designated as a first-year, second-year, third-year, or fourth-year cropland site, such that one-fourth of the cropland sites in each State would be sampled each fiscal year. Noncropland sites were handled in the same manner. Specimens were to be collected at each site no less than once every four years and not more than once per year. Soil specimens were obtained by compositing fifty soil cores, 2-inches in diameter by 3-inches in depth. Cropland specimens were to be ob- tained immediately before or at harvest time. 3.2.3 limitations of the Network The Rural Soils Network (RSN) design specified that 0.025 percent of the cropland acreage and 0.0025 percent of the noncrop- land acreage was to be sampled in each State. This criterion resulted in sample sizes that vary considerably from one State to another. Rhode Island received the fewest sampling units, four each of cropland and noncropland sites. Texas received the most, 744 cropland sites and 344 noncropland sites. Thus, reliable estimates of average pesticide levels are not available for some geographic areas. This is a minor limitation because estimates are not generally required for small geographic areas. A more serious limitation results from the purposive exclusion of several States in the Rocky Mountain regions in the implementation of the network, thus reducing the area to which statistical inferences are valid, which consists then of the total U.S., exclusive of those states omitted. 3.2.4 Summary of Polychlorinated Biphenyl Data from the Network Because the survey design resulted in a cyclic sample with a period of four years, the data can be summarized by round (group of four years) and by fiscal year. Only two soil specimens out of 6093 -8- ------- in round one (approximately fiscal 1969 to 1973) contained detectable amounts of PCBs. Table 3.4 summarizes the sample sizes and percent of specimens containing detectable levels of PCB by fiscal year (1969-1974) found in soil from cropland areas. During the same sampling period, no detectable levels of PCBs were found in 238 noncropland soil specimens. These data do not suggest any widespread contamination of PCB in cropland soil during the study period. The sample sizes for noncropland areas are insufficient to indicate the prevalence and levels of contamination. 3.3 National Surface Water Monitoring Program 3.3.1 General Description of the Monitoring Program The National Surface Water Monitoring Program (NSWMP) is based on the National Stream Quality Accounting Network (NASQAN) operated by the U.S. Geological Survey (USGS). As of May 13, 1980, there were 518 NASQAN fixed-site monitoring stations dispersed throughout the U.S. and Puerto Rico (USGS 1980). To form the NSWMP, 161 NASQAN stations were selected (Lucas D. et al 1980). Several of the 161 stations were never activated. A listing of the 152 NASQAN stations active as of September 1979 is given in Lucas D. et al (1980). The 152 active stations are geographically dispersed throughout the entire U.S. and Puerto Rico. The site locations were purposefully located- at sites that account for approximately 90% of the outflow from a watershed. For watersheds along the periphery of the country (coastal regions, Great Lakes, international boundaries) where the 90 percent outflow goal was impractical, a "representative" station or array of stations was chosen. 3.3.2 Limitations of Statistical Inferences Because the stations were selected purposefully, infer- ences to some larger target population such as all surface water and bottom sediment in the U.S. might be questioned. However, because the specimens are collected seasonally and for several years, differences among seasons and years at the collection sites may be detectable. 3.3.3 Summary of Polychlorinated Biphenyl Data Specimens of surface water are collected four times each year during the winter, spring, summer and fall quarters and speci- mens of sediment are collected twice a year during the spring and fall quarters. The quarters, winter, spring, summer, and fall, are associated in this presentation with the periods January-March, April-June, July- September, and October-December, respectively. These periods are used instead of the typical seasons because they more closely correspond to the actual sampling periods. Because the prevalence and levels of PCB vary considerably among seasons within a year, useful information may be lost if the seasons were combined for annual statistics. On the NSWMP computer accessible data files, PCBs are identified as PCB or one or more of several aroclor mixtures 1242, 1248, 1254 and 1260. Table 3.5 summarizes the prevalence of PCB and Aroclor 1254 in -9- ------- Table 3.4 Summary of Polychlorinated Biphenyl Data Collected from Cropland Areas of the Rural Soil Monitoring Network* Round 1 1 1 1 Subtotal Round 1 2 Fiscal Year 69 70 72 73 74 Total Specimen Material Soil Soil Soil Soil Soil Soil Sample Size 1722 1503 1486 1482 6093 1470 7663 Percent Detected 0.00 0.00 0.00 0.14 0.03 1.63 0.34 NA: Calculation is not applicable with available data. * Source: Calculated by the Research Triangle Institute from the computer accessible data files supplied by the U.S. Environmental Protection Agency. -10- ------- surface water by each season and fiscal year. Almost all specimens analyzed for 1254 were also analyzed for 1242, 1248, and 1260. Because only one, three, and three specimens of approximately 2400 specimens were positive for the three aroclors respectively, they are not included in the table. The percent detected is highest in 1975 and 1976, lowest in 1978 and between the two extremes in 1980. Table 3.6 summarizes the levels of the positive values of PCB and Aroclor 1254 found in surface water. The reader is cautioned that the extreme value of 900 ppb found in the spring of 1976 was measured before adequate quality control procedures were implemented in the spring of 1977 (Yonan, 1982). The next highest value is only 23 ppb of Aroclor 1254 also found in the spring of 1976. There is no apparent trend or seasonal patterns in the levels of the two PCB measures. Sediment was also analyzed for PCB and Aroclors 1242, 1248, 1254, and 1260. Because only three specimens contained detectable levels of 1248, its prevalence and levels are excluded from the summaries. Table 3.7 summarizes the prevalence of PCBs found in sediment by season and year. The percentage of specimens with detectable amounts are highest in 1975 and tend to decline to the lowest prevalence in 1979 with Aroclor 1254 consistently the most prevalent. The levels of the positive values displayed in Table 3.8 do not exihibit a declining pattern like the prevalence. Aroclor 1254 tends to be the highest of the compounds as well as the most prevalent. The reader is advised to cautiously interpret high values observed before the summer of 1977. Adequate quality control measures were not implemented until June of 1977 (Yonan, 1982). -11- ------- Table 3.5 Summary of the Prevalence of Polychlorinated Biphenyls in Surface Water Calendar Year 1975 1976 1977 1978 1979 1980 Quarter Winter Spring Summer Fall Winter Spring Summer Fall Winter Spring Summer Fall Winter Spring Summer Fall Winter Spring Summer Fall Winter Spring Summer Fall PCB Sample Size 32 141 99 124 396 126 116 78 2 322 4 1 13 8 26 21 31 25 2 79 1 17 92 0 110 0 0 0 0 0 PD* 12.5 35.5 16.2 12.1 15.9 10.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Aroclor Sample Size 0 4 0 3 7 6 40 143 140 329 140 140 145 143 568 124 135 143 133 535 146 151 142 152 591 116 98 135 65 414 1254 PD* 50.0 33.3 33.3 32.5 4.2 4.3 1.4 5.7 0.7 1.4 0.8 0.0 0.0 .8 0.0 0.0 5.6 0.0 0.9 2.0 9.6 4.6 *The percent detected (PD) is the number of specimens with greater than .15 parts per billion concentration divided by the sample size. Source: Calculated by the Research Triangle Institute from the NSWMP computer accessible data files. -12- ------- Table 3.6 Summary of Positive Values of Polychlorinated Biphenyls in Surface Water Calendar Year 1975 1976 1977 1978 1979 1980 Quarter Winter Spring Summer Fall Winter Spring Summer Fall Winter Spring Summer Fall Winter Spring Summer Fall Winter Spring Summer Fall Winter Spring Summer Fall Number 4 50 16 15 20 12 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PCB (ppb*) Minimum Median Maximum Number 0.18 0.35 2.65 0.15 0.26 2.44 2 0.15 0.21 0.28 0.15 0.22 0.49 1 0.15 0.20 1.15 2 0.15 0.34 900. OOt 13 6 6 2 8 1 2 1 0 0 1 0 0 8 0 1 2 13 3 Aroclor Minimum 0.15 0.99 0.38 0.15 0.15 0.16 0.23 0.15 0.24 0.23 0.22 21.43 0.15 0.18 0.26 0.17 0.28 1254 (ppb*) Median 0.20 0.99 0.45 0.96 0.50 0.46 3.15 0.15 0.24 0.24 0.22 21.33 0.28 0.18 0.32 0.74 0.37 Maximum 0.25 0.99 0.51 23.00 2.08 1.28 6.06 0.16 0.24 0.24 0.22 21.43 0.47 0.18 0.37 3.78 17.29 *ppb denotes parts per billion. tlhis high value needs to be interpreted cautiously because it was observed before adequate quality control procedures were implemented in the Spring of 1977. Source: Calculated by the Research Triangle Institute from the NSWMP computer accessible data fiels. -13- ------- Table 3.7 Summary of the Prevalence of Polychlorinated Bipbenyls in Bottom Sediment PCB Calendar Year 1975 1976 1977 1978 1979 Quarter Spring Fall Spring Spring Fall Spring Fall Spring Fall 1242 Sample Size 60 96 156 93 4 97 3 20 23 17 3 "20 53 1 ~54 PD* 58.3 47.9 8.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Sample Size 7 1 8 100 88 188 110 101 211 101 86 187 97 86 183 PD* 71.4 100.0 7.0 2.3 6.4 7.9 5.9 7.0 2.1 0.0 Aroclors 1254 Sample Size 26 39 ~65 101 90 191 110 101 211 101 86 187 97 86 183 PD* 92.3 97.4 22.8 25.6 17.3 19.8 18.8 19.8 8.3 8.1 1260 Sample Size 4 2 ~5 100 89 189 110 101 211 101 86 187 97 86 183 PD* 50.0 100.0 6.0 1.1 1.8 5.0 1.0 4.7 0.0 1.2 *The percent detected (PD) is the number of specimens greater than 1.5 ppb divided by the sample size. Source: Calculated by the Research Triangle Institute from the NSWMP computer accessible data files. -14- ------- Table 3.8 Summary of Positive Values of Polycblorinated Biphenyls in Bottom Sediment Calendar Tear Quarter 1975 Spring Fall 1976 1977 i 1978 i- Ol i 1979 Spring Fall Spring Fall Spring Fall Spring Fall PCB (pbb*) Aroclor 1242 (ppb*) Number 35 66 8 0 0 0 0 0 0 0 Minimum Hedian Maximum Number 1.61 4.82 73.25 5 1.50 5.49 457.8 1 2.14 14.37 164.0 7 2 7 8 6 6 2 0 Minimum 13.45 1.80 6.00 136.98 42.19 2.01 12.52 11.38 75.75 Median 70.50 1.80 12.24 805.99 117.69 30.76 80.42 35.17 326.88 Maximum 610.46 1.80 28.10 1475 188.06 88.77 2969 331.62 578.00 Aroclor 1254 (ppb*) Number 24 38 23 23 19 20 19 17 8 7 Minimum 2.08 1.54 1.80 2.84 4.80 1.67 1.82 1.60 2.35 1.70 Median 9.08 4.26 9.72 12.11 24.13 5.70 9.64 10.57 16.25 2.80 Maximum 256.21 46.54 1388 641 2064 2440 1752 88.00 130.6 7.30 Aroclor 1260 (ppb*) Number 2 2 4 1 2 5 1 4 0 1 Minimum 37.94 1.74 37.00 15.48 5.71 2.63 44.33 27.43 3.73 Median 55.47 8.59 62.26 15.48 12.90 14.30 44.33 46.99 3.73 Maximum 73.00 15.44 708.0 15.48 20.08 49.38 44.33 1053 3.73 *ppb denotes parts per billion. Source: Calculated by the Research Triangle Institute from the NSWMP computer accessible data files. ------- 4. POLYCHLORINATED BIPHENYLS IN FRESHWATER FISH 4.1 General Description of the Study Since 1967, the Fish and Wildlife Service (USDI) has sampled fresh water fishes at about 100 selected geographic stations throughout the Nation as a part of the National Pesticide Monitoring Program (NPMP). The sampled fishes have been analyzed for selected organochlorine pesti- cides and other contaminants, including PCBs and various toxic metals. A description of the program design (which has undergone significant changes since its inception) and the analytical procedures used are presented in Schmitt et al (1982). 4.2 Overview of the Study Design Among the 112 active NPMP stations, fish were collected from 109 stations located throughout the United States. Specimens were collected at about half the stations in even-numbered years and at the other half in odd-numbered years. Collections were made at 106 stations in the 1976-1977 two-year cycle, 108 stations in the 1978-1979 two-year cycle, and 102 stations yielded data in both two-year collection cycles. This 102-station subset of data from both years contained 591 specimens, which represents 95 percent of the 1976-1979 data. Collaborators were instructed to collect three specimens at each site; two of a representa- tive bottom-feeding species, and one of a representative predator species. Each specimen was composed of three to five whole, adult fish. Aliquots of the ground whole fish were subjected to electron-capture gas chromato- graphy to measure residues of the selected organochlorine contaminants. 4.3 Statistical Limitation of Data Summary of descriptive statistics including means, minimum and maximum concentrations, and percent of stations at which PCS residue was detected are presented in Schmitt et al (1982). Concentration levels for PCBs in the different fish species collected at each of the 109 individual stations are presented on both a wet-weight and a lipid-weight basis. The material that was available for this report, especially the description of how the monitoring stations were selected, was not suffi- ciently detailed to evaluate fully the data limitations for generalizing results (statistical inferences). Hence, before claiming the results apply to some particular population, say all fresh water fish in the U.S., the underlying methodology should be reviewed in more detail. However, because 102 stations were common between the two collection periods, comparing changes in the descriptive statistics between the two periods is meaningful. 4.4 Summary of Polychlorinated Biphenyls in Freshwater Fish Data Table 4.1 contains a summary of the levels of total PCS in freshwater fish measured from the 109 stations of the survey. Mean and maximum values for wet weight and lipid weight of PCB and percent occur- rence of residue concentrations for the two collection periods 1976-1977 and 1978-1979 are also given. In general, PCB residues were more widely distributed in the latter period, but appeared to be declining in some -16- ------- Table A.I Summary of Polychlorinated Biphenyls in Freshwater Fish" Wet Weight Mean Maximum Lipid Weight Mean Maximum •irk Percent Occurrence Total 1976-1977 0.87 70.60 7.99 738.61 91.5 PCB M8/G 1978-1979 0.84 92.77 8.79 483.17 98.1 * Source: Summarized by the Research Triangle Institute from the data provided by Schmitt et al. (1982). •irk Percent of stations showing detectable residues in at least one sample. -17- ------- areas of high concentration. The less-chlorinated PCBs (resembling Aroclor 1242) seem to be disappearing. The occurrence of PCBs were found at 92 percent of the stations sampled in 1976-1977 and 98 percent in 1978-1979. Maximum concentration did not change appreciably. Of the four PCB mixtures measured, residues resembling Aroclor 1254 were the most widespread. -18- ------- 5. SUMMARY AND CONCLUSIONS 5.1 Introduction In this chapter, an overview of the PCB data discussed in the previous chapters is presented. Because the designs of the sources were not matched, (that is, collecting specimens from the different media within close geographic proximity to each other), only general compari- sons among the media by time period are feasible. Even this type of comparison is limited because of the minimal amount of time period overlap among the available data from the media. Figure 5.1 illustrates the time periods of specimen collection by media. Urban and rural soils have the greatest amount of overlap, approximately six years. The other media studies overlap by three to five years. 5.2 Comparisons Among Media The urban soil network data does not exhibit any trends and the prevalence (percent detected) is relatively low in all years. Of course, the limitation of the survey design may preclude detecting trends even if they exist. The rural soil network data show essentially no PCB contamination (only 2 positives out of 6093 observations in round one) in cropland soil. The prevalence of PCBs in the water and sediment network data are higher than in the soils data. The prevalence appear to decrease in both water and sediment: that is, the later years (1978, 1979, and 1980) tend to have lower percents detected than the earlier years (1975, 1976, and 1977). The percents detected for PCBs in the tissue of freshwater fish were higher in the 1978-1979 time period than in the 1976-1977 time period (98.1 percent as compared with 91.5 percent) indicating similar levels of prevalence in fish and humans. Two general patterns appear to exist among the media. The preval- ence of PCBs appears to be increasing in freshwater fish tissues. The prevalence in the environmental media is lower and appears to be constant or decreasing. These two conflicting patterns may possibly be explained by the chemical properties of PCBs. PCBs tend to be soluble in organics and insoluble in water. Hence, they tend to migrate into the lipid portions of tissues and remain but tend to be less persistant in other media. -19- ------- Figure 5.1 Diagram of Collection Time Periods of Polychlorinated Biphenyl Data by Media Urban Soil Network Rural Soil Network Surface Water and wat^r Sediment Survey sediment Fresh Water Fish 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 Calendar Year Source: Developed by the Research Triangle Institute from information provided by the U.S. Environmental Protection Agency ------- 6. REFERENCES McDonald M, Hardy M, Drummond D 1981. National Soil Monitoring Program: Urban Soils Monitoring Network. Research Triangle Park, NC: Research Triangle Institute. RTI/1864/14/03-02I. Whitmore R, Rosenzweig M, and Hines J 1981. National Soil Monitoring Program. Research Triangle Park, NC: Research Triangle Institute. RTI/1864/14/03-011. USDA 1966. National Handbook for Updating the Conservation Needs Inven- tory United States Department of Agriculture. USEPA 1979. Analysis of EPA Pesticides Monitoring Networks. Prepared by the Research Triangle Institute for the Office of Toxic Substances, U.S. Environmental Protection Agency. Washington, DC. EPA-560/13-79-014. USGA 1980. National Water Data Exchange. U.S. Geological Survey. Reston, Virginia. Lucas D, Mason RE, Rosenzweig M et al. 1980. Recommendations for the National Surface Water Monitoring Program for Pesticides. Research Triangle Institute, Research Triangle Park, NC 27709. RTI/1864/14/01-01I. Schmitt, CJ, Ludke, JL and Walsh, D 1981. Organochlorine residues in fish, 1970-1974, National Pesticide Monitoring Program. Pesticide Monitoring Journal 14(4): 136«-206. Schmitt, CJ, M A Ribick, JL Ludke, and TW May 1982. Organochlorine Residues in Freshwater Fish, 1976-1979: National Pesticide Monitoring Program. J. in press, Pesticide Monitoring Journal. Yonan, J 1982 Personal communication on August 25, 1982. -21- ------- |