The toxic effects of the pesticide lindane on the early developmental stages of the fathead minnow

Toxic effects of the pesticide Lindane on the eggs, yolksac fry and larvae of the fathead minnow (Pimephales promelas) were investigated over 14 days at 25 and 18°C. The general objective was to understand the effects of the pesticide on the early life stages of the fish, and to evaluate the suitability of these stages as indicators of contaminated environments. Egg, yolk-sac and larval stages that had been exposed to 300, 120, 90, 60, 30, 10, 5, and 0 μg/L of Lindane at 25°C exhibited a 14d-LC₅₀ of 44 μg/L. Similarly, the same stages exposed to 300, 120, 90, 60, 30, 10, and 0 μg/L of Lindane at 18°C exhibited a 14d-LC₅₀ of 37 μg/L. Lower temperature thus seemed to increase the susceptibility of the fish to the pesticide. Mortality data were also used to determine the sensitivity of the early developmental stages of fish to the pesticide. At 25°C, the larval stage was the most sensitive stage. At 18°C, on the other hand, the most sensitive stage was the yolk-sac. Results obtained from experiments in which Lindane doses were applied at different intervals within the 14d-period supported these observations. Low temperatures had a marked effect on the sensitivity of the fathead minnow to Lindane. Embryos exposed to Lindane at 18°C showed different temporal distribution of mortality than those at 25°C. A delay in hatching and emergence of smaller larvae were also noted at 18°C. Lordoscoliosis, edemas and hemorrhages were the most common morphological changes induced by the pesticide during the larval stage. The frequency of these abnormalities was linearly related to doses of Lindane. Impaired swimming behavior was also noted, but it was not related to dosages.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Biology

Department dc:contributor.department

Biology

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1990

Author dc:creator

• Tatis, Anabel G.

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

etd-04252009-040353

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/42196