Lethal and sublethal responses to a sediment bound toxicant by two oligochaetes from Lake Michigan: stylodrilus heringianus and limnodrilus hoffmeisteri

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1987

OSTI ID:6995494

Keilty, T J

Short-term lethal, and short and long-term sublethal responses by Stylodrilus heringianus (Lumbriculidae) and Limnodrilus hoffmeisteri (Tubificidae) to sediments dosed with endrin were measured in single and mixed species tests. Ninety-six hour LC/sub 50/ values were 2588 +/- 1974 and 2757 +/- 995 ug/g dry weight sediment for S. heringianus and L. hoffmeisteri respectively. Ninety-six hour EC/sub 50/ burrowing avoidance values (concentration where 50% do not burrow) were one to two orders of magnitude lower than the LC/sub 50/'s. Short-term mixed species LC/sub 50/ data suggested that L. hoffmeisteri may benefit from the presence of S. heringianus. Long-term sublethal responses were quantified by measuring sediment reworking rates (the rate at which subsurface sediments are egested at the surface and re-buried) in laboratory microcosms. Rates were determined by monitoring a gamma-emitting /sup 137/Cesium marker layer with a well-collimated NaI detector. Sediment endrin concentrations ranged from 3 ng/g to 82 ug/g in six 1300 hour experiments. For S. heringianus, reworking rates were stimulated at low concentrations during the first half of experiments, followed by gradual decreases relative to controls. Stimulation of L. hoffmeisteri reworking was not observed. At high concentrations, early reworking rates were reduced for both species, followed by dramatic decreases later on. In mixed species experiments at high concentrations, the presence of S. heringianus enhanced the reworking of L. hoffmeisteri, although the reverse was not observed. Decreased mortality and increased post experimental dry weights of L. hoffmeisteri in mixed, relative to single species tests were also observed. Generally, post experimental worm weights were inversely related to sediment endrin loads, and bioconcentration factors for S. heringianus (10-40) were approximately fourfold that of L. hoffmeisteri (1-10).

• Research Organization: Michigan Univ., Ann Arbor (USA)
• OSTI ID: 6995494
• Country of Publication: United States
• Language: English

Related Subjects

520200* -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
550201 -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALKALI METAL ISOTOPES
ASCHELMINTHES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL ACCUMULATION
CESIUM 137
CESIUM ISOTOPES
CONTAMINATION
DOSES
ECOLOGICAL CONCENTRATION
ENVIRONMENTAL TRANSPORT
GREAT LAKES
HELMINTHS
INSECTICIDES
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
LAKE MICHIGAN
LAKES
LETHAL DOSES
MASS TRANSFER
MICROCOSMS
MORTALITY
NEMATODES
NUCLEI
ODD-EVEN NUCLEI
PESTICIDES
RADIOISOTOPES
SEDIMENTS
SURFACE WATERS
TOXICITY
TRACER TECHNIQUES
WEIGHT
YEARS LIVING RADIOISOTOPES