Anthony R. Carlson

Integrated assessment of contaminated sediments in the lower Fox River and Green Bay, Wisconsin.

Samples of sediment and biota were collected from sites in the lower Fox River and southern Green Bay to determine existing or potential impacts of sediment-associated contaminants on different ecosystem components of this Great Lakes area of concern. Evaluation of benthos revealed a relatively depauperate community, particularly at the lower Fox River sites. Sediment pore water and bulk sediments from several lower Fox River sites were toxic to a number of test species including Pimephales promelas, Ceriodaphnia dubia, Hexagenia limbata, Selenastrum capricornutum, and Photobacterium phosphorum. An important component of the observed toxicity appeared to be due to ammonia. Evaluation of three bullhead (Ictalurus) species from the lower Fox River revealed an absence of preneoplastic or neoplastic liver lesions, and the Salmonella typhimurium bioassay indicated relatively little mutagenicity in sediment extracts. Apparent adverse reproductive effects were noted in two species of birds nesting along the lower Fox River and on a confined disposal facility for sediments near the mouth of the river, and there were measurable concentrations of potentially toxic 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), and planar polychlorinated biphenyls (PCBs) both in the birds and in sediments from several of the study sites. Based on toxic equivalency factors and the results of an in vitro bioassay with H4IIE rat hepatoma cells, it appeared that the majority of potential toxicity of the PCB/PCDF/PCDD mixture in biota from the lower Fox River/Green Bay system was due to the planar PCBs. The results of these studies are discussed in terms of an integrated assessment focused on providing data for remedial action planning.

Growth and Survival of Channel Catfish and Yellow Perch Exposed to Lowered Constant and Diurnally Fluctuating Dissolved Oxygen Concentrations

Abstract Growth and survival were determined for duplicate lots of juvenile channel catfish (Ictalurus punctatus) and yellow perch (Perca flavescens) exposed for 69 and 67 days, respectively, to nearly constant dissolved oxygen (DO) concentrations at near air saturation (control), 6.5, 5.0, 3.5, and 2.0 mg/L. The following year juveniles of the same species were exposed to DO concentrations that gradually fluctuated diurnally at about 1.0 to 1.5 mg/L above and below the constant lowered DO levels of the previous year. At mean constant DO concentrations of 3.5 mg/L or less, channel catfish consumed less food and growth was significantly reduced (P = 0.05). Growth was not impaired by mean fluctuations of about 6.2 to 3.6 and 4.9 to 2 mgL, but was significantly reduced at fluctuations of about 3.1 to 1.0 mg/L. Similarly, at mean constant DO concentrations near 3.5 mg/L, yellow perch consumed less food but growth was not affected; at 2.0 mg/L less food was consumed and growth was significantly reduced (P = 0....

Toxicity of chlorinated benzenes to fathead minnows (Pimephales promelas)

The toxicities of several chlorinated benzene compounds to fathead minnows (Pimephales promelas) were determined. Chronic toxicities were estimated from 32–33 day embryo through early juvenile development exposures. The ranges between the highest no observable effect concentration (NOEC) and lowest observed effect concentration (LOEC) were 1,000–2,300, 570–1,000, and 240–410 μg/L for 1,3-dichlorobenzene (1,3-DCB), 1,4-dichlorobenzene (1,4-DCB), and 1,2,3,4-tetrachlorobenzene (1,2,3,4-TCB), respectively. Pentachlorobenzene (Penta-CB) and hexachlorobenzene (HCB) were non-toxic at the highest concentrations of 55 and 4.8 μg/L (near water saturation), respectively, that could be maintained in the test chambers. The tissue concentrations associated with the NOEC and LOEC for 1,3-DCB, 1,4-DCB and 1,2,3,4,-TCB were 120–160, 70–100, and 640–1,100 μg of chemical per gram of fish tissue (wet weight), respectively. The mean Penta-CB and HCB tissue concentration obtained at the NOEC of 55 and 4.8 μg/L were 390 and 97 μg/g, respectively. Mean bioconcentration factors obtained in these tests were 97, 110, 2,400, 8,400 and 22,000 for 1,3-DCB, 1,4-DCB, 1,2,3,4-TCB, Penta-CB and HCB, respectively. At a Penta-CB concentration of 130 μg/L (near water saturation) in a six day exposure conducted in the reservoir of the chemical saturating apparatus and control, juvenile fathead minnow behavior was affected and lipid content was reduced when compared to the control. Ninety-six hr LC50 values, obtained with juvenile fish, for 1,3-DCB, 1,4-DCB, and 1,2,3,4-TCB were 7,800, 4,200, and 1,100 (μg/L, respectively.

Effects of Lowered Dissolved Oxygen Concentrations on Channel Catfish (Ictalurus punctatus) Embryos and Larvae

Abstract Channel catfish embryos and resulting larvae were exposed to several reduced dissolved oxygen concentrations and control concentrations near air saturation at 25 and 28 C (7.8 and 7.3 mg/liter, respectively). At 25 C survival was similar but slightly reduced at 60% and 70% saturation (5.0 and 5.8 mg/liter) and was statistically less (P=0.01) at 30% and 50% saturation (2.4 and 4.2 mg/liter). No embryos hatched at 20% (1.7 mg/liter) and 25 C. Survival to the end of the test at 28 C was slightly reduced at 50%, 60%, and 70% saturation (3.8, 4.6, and 5.4 mg/liter) and was statistically less (P = 0.01) at 30% saturation (2.3 mg/liter). At all reduced oxygen concentrations at 25 and 28 C embryo pigmentation was lighter, duration of hatch was extended, feeding was delayed, and growth was reduced.

Induced Spawning of Largemouth Bass [Micropterus salmoides (Lacépède)]

Abstract When water temperature and photoperiod were manipulated, largemouth bass were induced to spawn successfully in laboratory tanks during the months of December, January, February, May, June and July.

Effect of Long-term Reduction and Diel Fluctuation in Dissolved Oxygen on Spawning of Black Crappie, Pomoxis nigromaculatus

Abstract Mature black crappies were exposed over winter in the laboratory to constant dissolved oxygen concentrations near 2.5, 4.0, 5.5, and 7.0 mg/liter. Starting on 26 April during a simulated spring-to-summer rise in water temperature, some were continued at the original oxygen concentrations while others were subjected to mean diel fluctuations ranging from 0.8 to 1.9 mg O2/liter above and below the original concentrations. Controls were maintained at concentrations near air saturation. No spawning occurred at the lowest fluctuating treatment of 1.8 to 4.1 mg/liter. This treatment also caused behavioral aberrations as the water temperature reached 20 C. Successful spawning occurred during all other treatments.

Effects of lowered dissolved oxygen concentration on the toxicity of 1,2,4-trichlorobenzene to fathead minnows

The primary objective of this study was to determine if the dissolved oxygen (DO) concentration affects the toxicity of 1,2,4-trichlorobenzene (1,2,4-TCB) to fathead minnows, Pimephales promelas, exposed during the embryonic-to-larval-juvenile development stage. This stage in the growth of the fathead minnow and several other species of fish has been found to be the most sensitive, or among the most sensitive, to chemical pollutants in life-cycle toxicity tests. The chemical 1,2,4-TCB has been identified as a priority pollutant by the US Environmental Protection Agency. It is used as an intermediate in the synthesis of a number of herbicides and insecticides and has been found as a contaminant in fish. It was selected as the chemical stressor in this study in order to provide information useful to the Agency in deriving water quality criteria for the protection of aquatic life.