Dataset Information

The spring runoff in Nebraska's (USA) Elkhorn River watershed and its impact on two sentinel organisms.

ABSTRACT: The objectives of the present study were to determine 1) if temporal variability influenced the toxicity of Elkhorn River, Nebraska, USA, water, and 2) if the toxic effect was consistent between 2 sentinel organisms, the fathead minnow (Pimephales promelas) and the northern leopard frog (Rana pipiens). During spring 2012, atrazine indicator strips were used to document the occurrence of agrichemical pulses in the Elkhorn River. Polar organic chemical integrative samplers (POCIS) were deployed for 14 d during both a pulse and a postpulse period as indicated by the atrazine strips. Pesticide concentrations detected in the POCIS extracts ranged from 1.6-fold to 281-fold higher during the pulse period compared to the postpulse period. Fish and frog bioassays were conducted for 7 d, and hepatic mRNA expression of vitellogenin (VTG) and estrogen receptor alpha (ER?) was determined by quantitative real-time polymerase chain reaction. Compared with lab water controls, fish exposed to water collected during an agrichemical pulse experienced significant reductions in VTG and ER?, whereas exposed female frogs did not. Male leopard frogs, in contrast, experienced significant increases in the expression of ER?, whereas pulse-exposed male minnows did not. The significant effects observed following agrichemical pulse exposure demonstrate that episodic agrichemical runoff adversely impacts sentinel organisms, and that the adverse impacts observed depend on the sex and species of the sentinel organism.

SUBMITTER: Knight LA

PROVIDER: S-EPMC3683351 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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The spring runoff in Nebraska's (USA) Elkhorn River watershed and its impact on two sentinel organisms.

Knight Lindsey A LA Christenson Matthew K MK Trease Andrew J AJ Davis Paul H PH Kolok Alan S AS

Environmental toxicology and chemistry 20130528 7

The objectives of the present study were to determine 1) if temporal variability influenced the toxicity of Elkhorn River, Nebraska, USA, water, and 2) if the toxic effect was consistent between 2 sentinel organisms, the fathead minnow (Pimephales promelas) and the northern leopard frog (Rana pipiens). During spring 2012, atrazine indicator strips were used to document the occurrence of agrichemical pulses in the Elkhorn River. Polar organic chemical integrative samplers (POCIS) were deployed fo ...[more]

PMID: 23504772

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Dataset Information

The spring runoff in Nebraska's (USA) Elkhorn River watershed and its impact on two sentinel organisms.

Publications

The spring runoff in Nebraska's (USA) Elkhorn River watershed and its impact on two sentinel organisms.

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