Daniel W. Sparks

Trace elements, organochlorines, polycyclic aromatic hydrocarbons, dioxins, and furans in lesser scaup wintering on the Indiana Harbor Canal

During the winter of 1993-94, male lesser scaup (Aythya affinis) were collected on the heavily polluted Indiana Harbor Canal (IHC), East Chicago, IN, USA, and examined for tissue contaminant levels. Lesser scaup collected on the IHC had higher concentrations of cadmium (Cd), mercury (Hg), selenium (Se), polychlorinated biphenyls (PCBs), selected organchlorine pesticides, polychlorinated dibenzodioxins, polychlorinated dibenzofurans, polycyclic aromatic hydrocarbons, and aliphatic hydrocarbons than reference birds. Of the scaup collected on the IHC, 44% had Cd concentrations in the liver considered above background for freshwater waterfowl (>3 microg/g dry wt.), 50% had Se concentrations in the liver above a level possibly harmful to the health of young and adult birds (>33 microg/g dry wt.), and 88% of the scaup carcasses exceeded the PCB human consumption guidelines for edible poultry in the USA (>3.0 microg/g lipid wt.). The ratio of pristane:n-heptadecane concentrations in 47% of lesser scaup collected on IHC was elevated above 1.0, which is indicative of chronic exposure to petroleum hydrocarbons.

External heart deformities in passerine birds exposed to environmental mixtures of polychlorinated biphenyls during development

Necropsy-observable cardiac deformities were evaluated from 283 nestling passerines collected from one reference site and five polychlorinated biphenyl (PCB)-contaminated sites around Bloomington and Bedford, Indiana, USA. Hearts were weighed and assessed on relative scales in three dimensions (height, length, and width) and for externally visible deformities. Heart weights normalized to body weight (heart somatic index) were decreased significantly at the more contaminated sites in both house wren (Troglodytes aedon) and tree swallow (Tachycineta bicolor). Heart somatic indices significantly correlated with log PCB concentrations in Carolina chickadee (Parus carolinesis) and tree swallow and with log 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalent values in tree swallow alone. Ventricular length was increased significantly in eastern bluebirds (Sialia sialis) and decreased significantly in Carolina chickadee and tree swallow from contaminated sites versus the reference site. Heart length regressed significantly against the log PCB concentrations (Carolina chickadee and tree swallow) or the square of the PCB concentrations (red-winged blackbird [Agelaius phoeniceus]) in a sibling bird. The deformities that were observed most at the contaminated sites included abnormal tips (pointed, rounded, or flattened), center rolls, macro- and microsurface roughness, ventricular indentations on the ventral or dorsal surface, lateral ventricular notches, visibly thin ventricular walls, and changes in overall heart shape. A pooled heart deformity index regressed significantly against the logged contaminant concentrations for all species except red-winged blackbird. These results indicate that developmental changes in heart morphometrics and shape abnormalities are quantifiable and may be sensitive and useful indicators of PCB-related developmental impacts across many avian species.

Organochlorine accumulation by sentinel mallards at the Winston-Thomas sewage treatment plant, Bloomington, Indiana

Farm-raised 12-month-old female mallards (Anas platyrhynchos) were released at the Winston-Thomas sewage treatment plant, Bloomington, Indiana. Five mallards were sacrificed at the start of the study and at approximately 10-day intervals through day 100. Concentrations of polychlorinated biphenyls (PCBs) in carcasses increased linearly with time of exposure and exceeded 16 μg/g wet weight by day 100; PCBs in breast muscle exceeded 3.9 μg/g by day 100. These PCB values are among the highest recorded for wild or sentinel waterfowl. PCB concentrations in breast muscle (26–523 μg/g lipid weight) were 50–1,000 times greater than human consumption guidelines for edible poultry in Canada (0.5 μg/g lipid weight) and 9–176 times greater than consumption guidelines for edible poultry in the United States (3.0 μg/g lipid weight). Additionally, PCB concentrations in carcass and breast muscle exceeded the threshold of the Great Lakes Sport Fish Consumption Advisory ‘do not eat’ category (1.9 μg/g wet weight) by day 20 and day 50, respectively. Hepatic cytochrome P450-associated monooxygenases including BROD (benzyloxyresorufin-O-dealkylase), EROD (ethoxyresorufin-O-dealkylase), and PROD (pentoxyresorufin-O-dealkylase) were induced over 5-fold compared to reference mallards. BROD, EROD, and PROD were each significantly correlated to total PCBs and to the toxicity of selected PCB congeners, relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin.

Movement Patterns of Wintering Lesser Scaup in Grand Calumet River—Indiana Harbor Canal, Indiana

Lesser scaup (Aythya affinis) winter in the Grand Calumet River—Indiana Harbor Canal (GCR-IHC) drainage into southern Lake Michigan, a polluted oasis in the highly urban and industrial corridor of northern Illinois and Indiana. The GCR-IHC is an important wintering area for lesser scaup in northwestern Indiana, especially after Lake Michigan freezes, because of the lack of other wildlife habitat in the area. We investigated the feeding and movement patterns of these wintering lesser scaup to better understand the ecological significance of this area to wintering waterfowl and to interpret contaminant levels in these lesser scaup. We implanted radio transmitters in 20 individuals in January 1994 and tracked them until early March 1994. Four lesser scaup disappeared and four died within the first 2 weeks after implantation; 12 lesser scaup remained in the GCR-IHC for the next 6–7 weeks. Individual radio-marked scaup (n = 12) were located in the GCR-IHC on an average of 62.2% (extreme values = 25–87%) of the searches. No radio-marked lesser scaup were located outside the GCR-IHC. Lesser scaup were feeding during 23% of the radio fixes.

Patterns in Stream Fish Assemblage Structure and Function Associated With a PCB Gradient

Stream fish assemblage structure and function were examined for significant response along a polychlorinated biphenyl (PCB) gradient from two PCB-contaminated streams (Clear Creek and Richland Creek watershed) at three locations and a control stream (Little Indian Creek), Indiana, USA. Fish were sampled in the summer months of 1995 and from 1999 to 2002. 51 fish assemblage attributes—including structure (i.e., fish composition) and function (i.e., trophic, reproductive, condition guilds), biomass, and index of biotic integrity (IBI) metric scores—were evaluated for significance according to an increasing PCB gradient. Eight biomass attributes of fish assemblages decreased with increasing PCB concentration: number of species biomass, number of sunfish biomass, percent sunfish biomass, number of sucker biomass, percent sucker biomass, biomass of sensitive species, percent sensitive species biomass, and percent carnivore biomass. Three biomass attributes increased with PCB concentration: percent minnow biomass, percent pioneer species biomass, and percent tolerant species biomass. Seven species composition and relative abundance characters decreased with increasing PCB concentration: number of species; number of darter, madtom, and sculpin; number of darter; number of sunfish; number of sucker; number of sensitive species; and percent individuals as carnivores. Percent individuals as pioneer species increased with increasing PCB concentration. Two IBI metrics, percent individuals as headwater species and number of minnow species, increased as PCB concentrations increased, whereas number of sucker species and percent individuals as pioneer species decreased with increasing PCB concentration class. We observed a direct response between decreased relative abundance and biomass of carnivores and increased relative abundance minnows as the PCB gradient increased. Total IBI score did not detect subtle changes to the fish community that were observed along a PCB gradient, whereas diagnostic analysis of the individual metrics did.

Preliminary Results Using the Early Embryo Teratogenesis Assay: A Comparison of Early Embryo Abnormalities with Late Embryo and Hatchling Teratogenic Changes

Classical evaluations of the effects of toxicants on development in birds for ecological impact assessments and teratogenic evaluation generally entail an evaluation of the late embryo, immediately before hatching, or young hatchling. In the laboratory, these studies generally require approximately three weeks before one can evaluate the late embryo or hatchling, and a full teratogenic evaluation of growth and developmental parameters is relatively time intensive. Recent studies have shown that many teratogenic abnormalities may be detected as soon as the affected organ system starts to develop or differentiate. The early embryo teratogenesis assay is being developed to reduce the amount of time needed to evaluate potential teratogenic or developmental toxicological effects. Embryos which have been exposed in the laboratory or in the natural environment are incubated (preferably in the laboratory) and sacrificed at known time points which correspond to the time when specific developmental indicators (such as the heart or visceral arches) have begun to develop. These embryos are then evaluated for the type and frequency of abnormalities manifested at each stage of development. We have begun a series of laboratory studies using both a laboratory model animal (the domestic chicken) and wildlife species (barn and tree swallows) which enable us to compare the early embryo abnormalities induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; chicken) or a mixture of environmental contaminants, which include TCDD-like compounds (swallow), to the abnormalities observed in the late embryo, hatchling or nestling.