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Kathy Lee

Publications and source records attributed to Kathy Lee.

33 records · Page 2Linked to original sources

USGS library for S-PLUS for Windows -- Release 4.0

Release 4.0 of the U.S. Geological Survey S-PLUS library supercedes release 2.1. It comprises functions, dialogs, and datasets used in the U.S. Geological Survey for the analysis of water-resources data. This version does not contain ESTREND, which was in version 2.1. See Release 2.1 for information and access to that version. This library requires Release 8.1 or later of S-PLUS for Windows. S-PLUS is a commercial statistical and graphical analysis software package produced by TIBCO corporation(http://www.tibco.com/). The USGS library is not supported by TIBCO or its technical support staff.

Open-File Report

Endocrine active chemicals and endocrine disruption in Minnesota streams and lakes: Implications for aquatic resources, 1994-2008

The U.S. Geological Survey, in cooperation with St. Cloud State University, Minnesota Department of Health, Minnesota Pollution Control Agency, Minnesota Department of Natural Resources, Metropolitan Council Environmental Services, and the University of Minnesota, has conducted field monitoring studies and laboratory research to determine the presence of endocrine active chemicals and the incidence of endocrine disruption in Minnesota streams and lakes during 1994–2008. Endocrine active chemicals are chemicals that interfere with the natural regulation of endocrine systems, and may mimic or block the function of natural hormones in fish or other organisms. This interference commonly is referred to as endocrine disruption. Indicators of endocrine disruption in fish include vitellogenin (female egg yolk protein normally expressed in female fish) in male fish, oocytes present in male fish testes, reduced reproductive success, and changes in reproductive behavior. The results from a series of studies during 1994–2008 demonstrate that endocrine active chemicals are present in Minnesota surface waters, indicating that aquatic organism exposure is likely. Endocrine active chemicals have been identified in wastewater-treatment plant effluent and surface waters downstream from discharge of wastewater-treatment plant effluent throughout Minnesota at low concentrations. Biological indicators of endocrine disruption have been detected in wild fish throughout Minnesota at sites directly downstream from wastewater-treatment plant effluent, indicating that endocrine active chemicals in effluent contribute to endocrine disruption in fish. This finding was confirmed in a controlled study exposing fathead minnows to wastewater-treatment plant effluent at an onsite fish exposure laboratory. During this controlled study, changes in biological responses coincided with changes in wastewater-treatment plant effluent composition demonstrating that effluent effects on fish endocrine systems are temporally variable. Although chemicals contributing to endocrine disruption in fish are complex, several laboratory studies have further confirmed that certain classes of chemicals, such as hormones and alkylphenols, which are components of wastewater-treatment plant effluent, affect the endocrine systems of fish through biochemical, structural, and behavioral disruption. Although these studies indicate that wastewater-treatment plant effluent is a conduit for endocrine active chemicals to surface waters, endocrine active chemicals also were present in surface waters with no obvious wastewater-treatment plant effluent sources. Endocrine active chemicals were detected and indicators of endocrine disruption in fish were measured at numerous sites upstream from discharge of wastewater-treatment plant effluent. These observations indicate that other unidentified sources of endocrine active chemicals exist, such as runoff from land surfaces, atmospheric deposition, inputs from onsite septic systems, or other groundwater sources. Alternatively, some endocrine active chemicals may not yet have been identified or measured. The presence of biological indicators of endocrine disruption in male fish indicates that the fish are exposed to endocrine active chemicals. However indicators of endocrine disruption in male fish does not indicate an effect on fish reproduction or changes in fish populations.

Minnesota

Water-Quality and Biological Characteristics and Responses to Agricultural Land Retirement in Three Streams of the Minnesota River Basin, Water Years 2006-08

Water-quality and biological characteristics in three streams in the Minnesota River Basin were assessed using data collected during water years 2006-08. The responses of nutrient concentrations, suspended-sediment concentrations, and biological characteristics to agricultural land retirement also were assessed. In general, total nitrogen, suspended-sediment, and chlorophyll-a concentrations, and fish resource quality improved with increasing land retirement. The Chetomba Creek, West Fork Beaver Creek, and South Branch Rush River subbasins, which range in size from about 200 to 400 square kilometers, have similar geologic and hydrologic settings but differ with respect to the amount, type, and location of retired agricultural land. Total nitrogen concentrations were largest, with a mean of 15.0 milligrams per liter (mg/L), in water samples from the South Branch Rush River, a subbasin with little to no agricultural land retirement; total nitrogen concentrations were smaller in samples from Chetomba Creek (mean of 10.6 mg/L) and West Fork Beaver Creek (mean of 7.9 mg/L), which are subbasins with more riparian or upland land retirement at the basin scale. Total phosphorus concentrations were not related directly to differing land-retirement percentages with mean concentrations at primary data-collection sites of 0.259 mg/L in the West Fork Beaver Creek subbasin, 0.164 mg/L in the Chetomba Creek subbasin, and 0.180 mg/L in the South Branch Rush River subbasin. Temporal variation in water quality was characterized using data from in-stream water-quality monitors and storm-sediment data. Fish data indicate better resource quality for the West Fork Beaver Creek subbasin than for other subbasins likely due to a combination of factors, including habitat quality, food resources, and dissolved oxygen characteristics. Index of biotic integrity (IBI) scores increased as local land-retirement percentages (within 50 and 100 meters of the streams) increased. Data and analysis from this study can be used to evaluate the success of agricultural management practices and land-retirement programs for improving stream quality.

Scientific Investigations Report

Occurrence of endocrine active compounds and biological responses in the Mississippi River— Study design and data, June through August 2006

Concern that selected chemicals in the environment may act as endocrine active compounds in aquatic ecosystems is widespread; however, few studies have examined the occurrence of endocrine active compounds and identified biological markers of endocrine disruption such as intersex occurrence in fish longitudinally in a river system. This report presents environmental data collected and analyzed by the U.S. Geological Survey, Minnesota Pollution Control Agency and St. Cloud State University as part of an integrated biological and chemical study of endocrine disruption in fish in the Mississippi River. Data were collected from water, bed sediment, and fish at 43 sites along the river from the headwaters at Lake Itasca to 14 miles downstream from Brownsville, Minnesota during June through August 2006. Twenty-four individual compounds were detected in water samples, with cholesterol, atrazine, N,N-diethyl-meta-toluamide, metolachlor, and hexahydrohexamethylcyclopentabenzopyran detected most frequently (in at least 10 percent of the samples). The number of compounds detected in water per site ranged from 0 to 8. Forty individual compounds were detected in bed-sediment samples. The most commonly detected compounds (in at least 50 percent of the samples) were indole, beta-sitosterol, cholesterol, beta-stigmastanol, 3-methyl-1H-indole, p-cresol, pyrene, phenol, fluoranthene, 3-beta coprostanol, benzo[a]pyrene, acetophenone, and 2,6-dimethylnaphthalene. The total number of detections in bed sediment (at a site) ranged from 3 to 31. The compounds NP1EO, NP2EO, and 4-nonylphenol were detected in greater than 10 percent of the samples. Most (80 percent) female fish collected had measurable concentrations of vitellogenin. Vitellogenin also was detected in 62, 63, and 33 percent of male carp, smallmouth bass, and redhorse, respectively. The one male walleye sample plasma sample analyzed had a vitellogenin detection. Vitellogenin concentrations were lower in male fish (not detected to 10.80 micrograms per milliliter) than female fish (0.04 to 248,079 micrograms per milliliter). Gonadosomatic Index values ranged from 0.02 to 7.49 percent among all male fish and were greater for male carp than for the other three species. No intersex (oocytes present in testes tissue) was found in any male fish sampled.

Minnesota, Wisconsin

Alkylphenols, other endocrine-active chemicals, and fish responses in three streams in Minnesota — Study design and data, February-September 2007

This report presents the study design and environmental data for an integrated chemical and biological study of three streams (South Fork Crow River, Redwood River, and Grindstone River) that receive wastewater in Minnesota. The objective of the study was to identify distribution patterns of endocrine-active chemicals and other organic chemicals indicative of wastewater, and to identify fish responses in the same streams. Endocrine-active chemicals are a class of chemicals that interfere with the natural regulation of endocrine systems, and an understanding of their distribution in aquatic systems is important so that aquatic organism exposure can be evaluated. This study was a cooperative effort of the U.S. Geological Survey (USGS), the Minnesota Pollution Control Agency, and St. Cloud State University (St. Cloud, Minn.). The USGS collected and analyzed water and quality-assurance samples and measured streamflow during six sampling events in each of three streams. Water samples were collected upstream from and at two successive points downstream from wastewater-treatment plant (WWTP) effluent discharge and from treated effluent from February through September 2007. Bed-sediment samples were collected during one sampling period at each of the stream locations. Water and bed-sediment samples were analyzed for endocrine-active chemicals including alkylphenols, alkylphenol polyethoxylates, and nonylphenol ethoxycarboxlylates (NPECs). Water samples also were analyzed for major ions, nutrients, and organic carbon. In addition, as part of an intensive time-series investigation, the USGS staff collected daily water samples for 8 weeks from the Redwood River near Marshall, Minn., for analyses of total alkylphenols and atrazine. St. Cloud State University staff collected and analyzed fish to determine male fish responses at all water sampling sites and at an additional site near the discharge of wastewater-treatment plant effluent to these streams. Male fish responses included the presence and concentration of vitellogenin in plasma, gonadosomatic indices, and histological characterizations of liver and testes tissue. Hydrologic, chemical and biological characteristics were different among sites. The percentage of streamflow contributed by WWTP effluent (ranging from less than 1 to 79 percent) was greatest at the South Fork Crow River and least at the Grindstone River. WWTP effluent generally contributed the greatest percentage of streamflow during winter and late summer when streamflows were low. A wide variety of chemicals were detected. More chemicals were detected in WWTP effluent samples than in stream samples during most time periods. The most commonly detected chemicals in samples collected monthly and analyzed at the USGS National Research Program Laboratory were 2,6-di- tert -butyl-1,4-benzoquinone, 2,6-di- tert -butyl-4-methylphenol, 3- beta -coprostanol, 4-methylphenol, 4-nonylphenol (NP), 4- tert -octylphenol, bisphenol A, cholesterol, ethylenediaminetetraacetic acid, and triclosan. The chemicals 4-nonylphenolmonoethoxycarboxylate (NP1EC), 4-nonylphenoldiethoxycarboxylate (NP2EC), and 4-nonylphenoltriethoxycarboxylate (NP3EC) also were detected. Excluding nondetections, the sum of NP1EC through NP3EC concentrations ranged from 5.1 to 260 µg/L among all samples. NP was detected in upstream, effluent, and downstream samples in each stream during at least one time period. NP was detected in 49 percent of environmental samples. Excluding nondetections, concentrations of NP ranged from 100 to 880 nanograms per liter among all samples. NP was also detected in more than one-half of the bed-sediment samples. The most commonly detected wastewater indicator chemicals in samples analyzed by schedule 4433 at the USGS National Water Quality Laboratory were 3,4-dichlorophenyl isocyanate, acetyl-hexamethyl-tetrahydronaphthalene, benzophenone, cholesterol, hexahydrohexamethyl-cyclopenta-benzopyran, N,N-diethyl- meta -toluamide, and tri(dichloroisopropyl) phosphate. Male fish responses were the focus of the fish analyses, and 508 male fish were collected among all sampling sites. Vitellogenin was detected in 57 percent of the 415 male fish analyzed; concentrations ranged from an estimated value of 0.1 to 330 micrograms per milliliter (µg/mL) (average of 17.1 µg/mL). Intersex (the presence of oocytes in testes tissue) was observed in only one fathead minnow from an upstream site on the Grindstone River.

Minnesota

Reproductive responses of male fathead minnows exposed to wastewater treatment plant effluent, effluent treated with XAD8 resin, and an environmentally relevant mixture of alkylphenol compounds

On-site, continuous-flow experiments were conducted during August and October 2002 at a major metropolitan wastewater treatment plant (WWTP) to determine if effluent exposure induced endocrine disruption as manifested in the reproductive competence of sexually mature male fathead minnows ( Pimephales promelas ). The fathead minnows were exposed in parallel experiments to WWTP effluent and WWTP effluent treated with XAD8 macroreticular resin to remove the hydrophobic-neutral fraction which contained steroidal hormones, alkylphenolethoxylates (APEs), and other potential endocrine disrupting compounds (EDCs). The effluent composition varied on a temporal scale and the continuous-flow experiments captured the range of chemical variability that occurred during normal WWTP operations. Exposure to WWTP effluent resulted in vitellogenin induction in male fathead minnows, with greater response in October than in August. Concentrations of ammonia, APEs, 17β-estradiol, and other EDCs also were greater in October than in August, reflecting a change in effluent composition. In the October experiment, XAD8 treatment significantly reduced vitellogenin induction in the male fathead minnows relative to the untreated effluent, whereas in August, XAD8 treatment had little effect. During both experiments, XAD8 treatment removed greater than 90% of the APEs. Exposure of fish to a mixture of APEs similar in composition and concentration to the WWTP effluent, but prepared in groundwater and conducted at a separate facility, elicited vitellogenin induction during both experiments. There was a positive relation between vitellogenin induction and hepatosomatic index (HSI), but not gonadosomatic index (GSI), secondary sexual characteristics index (SSCI), or reproductive competency. In contrast to expectations, the GSI and SSCI increased in males exposed to WWTP effluent compared to groundwater controls. The GSI, SSCI, and reproductive competency were positively affected by XAD8 treatment of the WWTP effluent.

Aquatic Toxicology

Geomorphic characteristics and classification of Duluth-area streams, Minnesota

In 2003 and 2004, a geomorphic assessment of streams in 20 watersheds in the Duluth, Minn., area was conducted to identify and summarize geomorphic characteristics, processes, disturbance mechanisms, and potential responses to disturbance. Methods used to assess the streams included watershed characterization, descriptions of segment slopes and valley types, historical aerial photograph interpretation, and rapid field assessments and intensive field surveys of stream reaches. Geomorphic conditions were summarized into a segment-scale classification with 15 categories mainly based on drainage-network position and slope, and, secondarily, based on geologic setting, valley type, and dominant geomorphic processes. Main causes of geomorphic disturbance included historical logging and agriculture, and ongoing urban development, human-caused channel alterations, road and storm sewer drainage, ditching, hiking trails, and gravel pits or quarries. Geomorphic responses to these disturbances are dependent on a combination of drainage-network position, slope, and geologic setting. Geologic setting is related to drainage-network position because the geologic deposits parallel the Lake Superior shoreline. Headwater streams in large watersheds flow over glacial deposits above altitudes of about 1,200 feet (ft). Headwater tributaries and upper main stems have ditch-like channels with gentle slopes and no valleys. Urban development and road drainage cause increased runoff and flood peaks in these segments resulting in channel widening. Below about 1,200 ft, main-stem segments generally are affected by bedrock type and structure and have steep slopes and confined or entrenched valleys. Increases in flood peaks do not cause incision or widening in the bedrock-controlled valleys; instead, the flow and scour areas are expanded. Feeder tributaries to these main stems have steep, confined valleys and may be sources for sediment from urban areas, road runoff, or storm sewer outfalls. Main-stem segments near the glacial deposits/surficial bedrock contact (1,000–1,200 ft) have the most potential for response to disturbance because they tend to have narrow valleys with sandy glacial lakeshore deposits and moderate slopes. Increases in flood peaks (from upstream increases in runoff) increase the potential for landslides and mass wasting from valley sides as well as channel widening.

Minnesota

Physical, chemical, and biological characteristics of Sturgeon Lake, Goodhue County, Minnesota, 2003-04

The U.S. Geological Survey, in cooperation with the Prairie Island Indian Community and the Minnesota Department of Natural Resources, conducted a study of Sturgeon Lake (a backwater lake in Navigation Pool 3 of the Mississippi River) during 2003-04 to describe the physical, chemical, and biological characteristics of the lake. Riparian and shoreline areas surrounding Sturgeon Lake consist primarily of deciduous tree and shrub cover with minimal amounts of commercial or residential land use. Woody debris and aquatic vegetation are the major types of physical habitat suitable for fish and invertebrates. Among 10 bottom-sediment sampling sites, 24 organic wastewater compounds, 1 organochlorine pesticide metabolite (p,p’DDE), and total polychlorinated biphenyls (PCBs) were detected in the bottom sediments of Sturgeon Lake. The most prevalent class of compounds detected were polyaromatic hydrocarbons. Other classes of compounds detected include sterols, disinfectants, plastic components, alkylphenols, and fragrances. Three compounds detected (bisphenol A, benzo[a]pyrene, and triclosan) are considered endocrine disrupting compounds. Twenty-one and 49 invertebrate taxa were identified from 10 bottom-sediment and 6 woody-debris/vegetation samples, respectively. Most of the taxa were Diptera in the family Chironomidae. The most common invertebrate in terms of density in bottom-sediment samples was the burrowing mayfly ( Hexagenia sp.). Trichoptera in the families Hydropsychidae or Polycentropodidae were common in most of the woody-debris samples. The presence of the Hexagenia larvae in samples indicates that the bottom sediments are stable and that dissolved oxygen concentrations in the lake do not drop to acute or sub-lethal anoxic conditions. Backwater lakes such as Sturgeon Lake are important areas of habitat for aquatic organisms along the Mississippi River, and this report provides baseline physical, chemical, and biological information that resource managers can compare with future investigations.

Minnesota

Presence and distribution of organic wastewater compounds in wastewater, surface, ground, and drinking waters, Minnesota, 2000-02

Selected organic wastewater compounds (OWCs) such as household, industrial, and agricultural-use compounds, pharmaceuticals, antibiotics, and sterols and hormones were measured at 65 sites in Minnesota as part of a cooperative study among the Minnesota Department of Health, Minnesota Pollution Control Agency, and the U.S. Geological Survey. Samples were collected in Minnesota during October 2000 through November 2002 and analyzed for the presence and distribution of 91 OWCs at sites including wastewater treatment plant influent and effluent; landfill and feedlot lagoon leachate; surface water; ground water (underlying sewered and unsewered mixed urban land use, a waste dump, and feedlots); and the intake and finished drinking water from drinking water facilities. There were 74 OWCs detected that represent a wide variety of use. Samples generally comprised a mixture of compounds (average of 6 OWCs) and 90 percent of the samples had at least one OWC detected. Concentrations for detected OWCs generally were less than 3 micrograms per liter. The ten most frequently detected OWCs were metolachlor (agricultural-use herbicide); cholesterol (sterol primarily associated with animal waste); caffeine (stimulant), N,N-diethyl- meta -toluamide (DEET) (topical insect repellant); bromoform (disinfection by product); tri(2-chloroethyl)phosphate (flame-retardant and plastic component); beta -sitosterol (plant sterol that is a known endocrine disruptor); acetyl-hexamethyl-tetrahydro- naphthalene (AHTN) (synthetic musk widely used in personal care products, and a known endocrine disruptor); bisphenol-A (plastic component and a known endocrine disruptor); and cotinine (metabolite of nicotine). Wastewater treatment plant influent and effluent, landfill leachate, and ground water underlying a waste dump had the greatest number of OWCs detected. OWC detections in ground-water were low except underlying the one waste dump studied and feedlots. There generally were more OWCs detected in surface water than ground water, and there were twice as many OWCs detected in the surface water sites downstream from wastewater treatment plant (WWTP effluent than at sites not directly downstream from effluent. Comparisons among site classifications apply only to sites sampled during the study. Results of this study indicate ubiquitous distribution of measured OWCs in the environment that originate from numerous sources and pathways. During this reconnaissance of OWCs in Minnesota it was not possible to determine the specific sources of OWCs to surface, ground, or drinking waters. The data indicate WWTP effluent is a major pathway of OWCs to surface waters and that landfill leachate at selected facilities is a potential source of OWCs to WWTPs. Aquatic organism or human exposure to some OWCs is likely based on OWC distribution. Few aquatic or human health standards or criteria exist for the OWCs analyzed, and the risks to humans or aquatic wildlife are not known. Some OWCs detected in this study are endocrine disrupters and have been found to disrupt or influence endocrine function in fish. Thirteen endocrine disrupters, 3- tert -butyl-4-hydoxyanisole (BHA), 4- cumylphenol, 4- normal -octylphenol, 4- tert -octylphenol, acetyl-hexamethyl-tetrahydro-naphthalene (AHTN), benzo[α]pyrene, beta-sitosterol, bisphenol-A, diazinon, nonylphenol diethoxylate (NP2EO), octyphenol diethoxylate (OP2EO), octylphenol monoethoxylate (OP1EO), and total para -nonylphenol (NP) were detected. Results of reconnaissance studies may help regulators who set water-quality standards begin to prioritize which OWCs to focus upon for given categories of water use.

Minnesota

Influence of local riparian cover and watershed runoff potential on invertebrate communities in agricultural streams in the Minnesota River Basin

During the summer of 1997, 23 streams in the highly agricultural Minnesota River Basin were studied to determine the influence of local riparian cover conditions (wooded or open) and watershed runoff potential (high or low) on invertebrate community composition. A two by two-factorial analysis of variance was used to determine differences in invertebrate community measures among the design classes While it is difficult to determine the relative influence of watershed runoff potential and local riparian cover, invertebrate communities may be more strongly influenced by local wooded riparian cover than by watershed runoff potential. Invertebrate community measures indicate greater degradation at the open riparian cover, high runoff potential sites and less degradation at the wooded riparian cover, low runoff potential sites. In addition, differences between streams with wooded riparian cover and sites with open riparian cover were greater in watersheds with high runoff potential. The variance explained by riparian cover and runoff potential is relatively independent of other land-use effects. Wooded riparian cover influences invertebrate community composition by its relation to the other physical environmental variables. This study indicates that wooded riparian cover may be effective in maintaining stream biotic integrity in watersheds dominated by agricultural land use.

Iowa, Minnesota, South Dakota

Relation of periphyton and benthic invertebrate communities to environmental factors and land use at selected sites in part of the upper Mississippi River basin, 1996-98

The Upper Mississippi River Basin is one of the hydrologic systems selected for study by the National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey. NAWQA utilizes a multi-disciplinary approach to explain factors that affect water quality. Part of the NAWQA design addresses the relation of land use and environmental factors to periphyton and benthic invertebrate communities in streams. This report focuses on a 122,000 square kilometer area of the Mississippi River Basin, including the Twin Cities metropolitan area (TCMA). The northeastern part of the study area is forested, the southwestern part is agricultural, and the central part is transitional between forest and agriculture. Sampling sites were selected based on a process that identified small streams in predominantly forested, agricultural, and urban settings, and large river sites on the Mississippi River and major tributaries. Periphyton and benthic invertebrate communities were evaluated at each site. Compared to the forested site, periphyton density and biovolume in small streams generally increased as nutrient concentrations associated with urban and agricultural land use increased. Periphyton communities varied within agricultural and urban streams, indicating that physical and chemical factors other than land use also affect periphyton communities. Benthic invertebrate communities also are affected by land use and associated stream habitat. There were few intolerant taxa (Ephemeroptera and Plecoptera) in urban streams, potentially due to high streamflow variability and contaminants from runoff. Ephemeroptera taxa richness was greatest in the agricultural streams. The most abundant Ephemeroptera taxa were those tolerant to high concentrations of suspended sediment. Richness of Plecoptera and Trichoptera taxa were greatest in the forested stream. Biological communities in the St. Croix and Minnesota River generally reflected relatively homogeneous land uses. Biological communities in the Mississippi River reflected changes in water quality and physical habitat as the Minnesota and St. Croix Rivers join the Mississippi River. Periphyton density and biovolume, and the relative abundance of blue-green algae density increased in the Mississippi River at the confluence compared to the Minnesota and St. Croix Rivers. Relative abundance of benthic invertebrate taxa richness and diversity generally decreased downstream in the large rivers as urban and agricultural land use become more prevalent. Impoundments and dredging of the Mississippi River in and downstream from the TCMA exacerbate effects of increasing river size to produce a more lake-like system.

Iowa, Minnesota, North Dakota, South Dakota, Wisco

It's not just how high; it's how clean: Sampling the spring 2001 flood in the Upper Mississippi River Basin

Floods can cause water-quality problems because of the large amounts of contaminants (sediment, nutrients, pesticides, and bacteria) that can be transported by floodwaters. during the flood on the Upper Mississippi River in 2001, water-quality and water-quality data were collected during near-record streamflow. This is the first time that samples for determining organic wastewater contaminants (pharmaceuticals, hormones, and industrial/household use compounds) and pesticide degradates have been collected during a flood of this magnitude.

Illinois, Iowa, Minnesota, Missouri, Wisconsin

Use of biological characteristics of common carp ( Cyprinus carpio ) to indicate exposure to hormonally active agents in selected Minnesota streams, 1999

The presence of hormonally active agents (HAAs) was determined in selected Minnesota streams using biological characteristics (measures of endocrine disruption) of common carp ( Cyprinus carpio ) exposed to wastewater treatment plant (WWTP) effluent and runoff from agricultural and forested land. Four biological characteristics of common carp were used as indicators of HAAs in the streams selected for this study: (1) high concentrations of vitellogenin in male fish and low concentrations in female fish, (2) high or low plasma concentrations of the sex steroid hormones (17β-estradiol and 11-ketotestosterone), (3) low gonado-somatic index (GSI) (gonad weight divided by total body weight multiplied by 100) values, and (4) abnormal gonad histopathology (high percent of atretic oocytes in female ovaries and high percent ceroid/lipofuscin tissue in male or female gonads). The study design was a paired site approach targeting sites downstream and upstream of WWTP discharges on different streams. Male (221 individuals) and female (201 individuals) common carp were collected using electrofishing techniques from seven streams with sites at two locations (upstream and downstream of WWTPs), and eight sites located downstream of WWTPs with no upstream-paired sites. Samples were collected between August 3 and September 13, 1999. The presence of HAAs in selected Minnesota streams was indicated by biological characteristics in common carp. Biological characteristics used in this study identified WWTP effluent as a potential source of HAAs. Additionally, fish located at sites upstream of WWTP effluent primarily draining agricultural land show indications of HAAs, which may be the result of agricultural runoff or other sources of HAAs. There was variability among all sites and among sites within each site group. Differences among sites may be due to differences in water chemistry or fish exposure time. Natural variation in the biological characteristics may account for some of the differences observed in this study. This study and others indicate the presence of HAAs in surface water and the potential signs of endocrine disruption in resident fish populations. Detailed controlled studies could confirm the effects of particular chemicals such as pesticides or components of WWTPs on fish reproduction and population structure.

Minnesota

Water quality, physical habitat, and fish-community composition in streams in the Twin Cities metropolitan area, Minnesota, 1997-98

Water quality, physical habitat, and fish-community composition were characterized at 13 Twin Cities metropolitan area streams during low-flow conditions, September 1997. Fish communities were resampled during September 1998. Sites were selected based on a range of human population density. Nutrient concentrations were generally low, rarely exceeding concentrations found in agricultural streams or water-quality criteria. Seventeen pesticides and five pesticide metabolites were detected, with atrazine being the only pesticide detected at all 13 streams. Colony counts of fecal coliform bacteria ranged from 54 to greater than 11,000 colonies per 100 mL. Instream fish habitat was sparse with little woody debris and few boulders, cobble, or other suitable fish habitat. Thirty-eight species and one hybrid from 10 families were collected. Fish communities were characterized by high percentages of omnivores and tolerant species with few intolerant species. Index of Biotic Integrity scores were low, with most streams rating fair to very poor. Percent impervious surface was positively correlated with sodium and chloride concentrations and human population density, but was negatively correlated with fish species richness and diversity. Urban land use and human population density influence fish communities and water quality in Twin Cities metropolitan area streams. Other factors that may influence fish community composition include percent impervious cover, water chemistry, water temperature, geomorphology, substrate, instream habitat, and migration barriers.

Minnesota

Water-quality assessment of the Upper Mississippi River Basin, Minnesota and Wisconsin: Polychlorinated biphenyls in common carp and walleye fillets, 1975-95

Spatial and temporal distribution of polychlorinated biphenyls (PCBs) in common carp ( Cyprinus carpio ) and walleye ( Stizostedion vitreum ) fillets from rivers in the Upper Mississippi River Basin upstream of the outlet of Lake Pepin are summarized. PCB concentrations in common carp and walleye fillets collected from rivers in the UMIS during 1975-95 by the Minnesota Fish Contaminant Monitoring Program (MFCMP) and the Wisconsin Department of Natural Resources (WDNR) were analyzed. PCBs in fish tissue are of concern because PCBs are potentially toxic, teratogenic, and are linked to poor fetal development and endocrine disruption in fish and other animals including humans, that consume fish. This summary was part of an analysis of historical data for the Upper Mississippi River (UMIS) study unit of the National Water-Quality Assessment (NAWQA) Program. The UMIS study unit is a 47,000 square-mile basin that includes the drainage of the Mississippi River upstream of the outlet of Lake Pepin and encompasses the Twin Cities metropolitan area. PCB concentrations for individual samples at all sites ranged from 0.07 to 33.0 milligrams per kilograms (mg/kg) for common carp and from 0.07 to 9.8 mg/kg for walleye during 1975-95. During 1975-79 and 1980-87, 10 and 4 percent of walleye samples and 45 and 36 percent of common carp samples, respectively, exceeded the U.S. Food and Drug Administration guideline of 2 mg/kg PCB in fish tissue. PCB concentrations in individual common carp and walleye samples were below 2 mg/kg after 1987. Median PCB concentrations at individual sites and within stream segments were generally greatest in common carp and walleye from Mississippi River segments in the TCMA during 1975-79 and 1980-87. There was a significant difference among lipid-normalized PCB (LNPCB) concentrations in common carp, considering all stream segments combined, during all three time periods (1975-79, 1980-87, and 1988-95). LNPCB concentrations in common carp and walleye at those stream segments upstream or outside the TCMA were generally lower than those in UMR segments within the TCMA. The spatial distribution of PCB and LNPCB concentrations in common carp and walleye correspond with historical point- and non point-source PCB inputs in the densely populated TCMA, and concentrations in fish were greater in areas that historically had elevated PCB concentrations in bed sediment. Median PCB concentrations in common carp and walleye at individual sites were greatest during 1975-79 and 1980-87, and least during 1988-95 at most sites. Most of the river segments exhibited over 80 percent decline in median PCB concentrations in common carp and walleye between the 1975-79 and 1988-95 time periods. The results from these temporal analyses were similar to those of other studies in the United States and in Minnesota and Wisconsin that reported a significant downward trend in PCB concentrations in fish. Although, PCB concentrations have decreased during 1975-95, low concentrations of PCBs still remain in the aquatic environment despite the fact that PCBs were banned nearly 20 years ago.

Minnesota, Wisconsin