Weathered Alaska North Slope crude oil (ANS 521) was subjected to biodegradation in vigorously stirred incubations for 14 days at 15 +/- 1 degrees C in 20/1000 salinity sterilized seawater, amended with nutrients and inoculated with a @entity7294 -degrading microorganism (EI2V) isolated from an oil-contaminated beach in Prince William Sound, Alaska. A total of 13.7 mg/L @entity12360 ( @entity12360 ) was recovered from the incubation of weathered ANS 521. @entity137 / teratogenicity tests were conducted with @entity12360 recovered from the biodegradation system using embryonic and larval @entity27857 , @entity27857 . Exposures were begun at 4, 48, and 96 h postfertilization of herring eggs. Exposure concentrations were 1, 10, and 100% of the original concentration of @entity12360 recovered from incubations (redissolved in 20/1000 salinity sterile seawater at 15 +/- 1 degrees C). Sterile 20/1000 salinity seawater without the addition of redissolved neutral fraction was used as a control. Significant (p < or = 0.05) embryo mortality or teratogenic responses were observed at @entity12360 concentrations of 10 and 100%. On days 5 through 8 of embryogenesis, counts of heart contraction rates were significantly lower (p < or = 0.05) at the 100% @entity12360 concentration for embryos exposed beginning at 4 and 48 h postfertilization. Grow-out of larvae from selected exposures was conducted. High mortality was noted in larvae exposed to the 10% @entity12360 concentration beginning at 4 and 48 h postfertilization. Most of these larvae died 5 to 8 days after hatching when they elicited vertebral displacements at a time concurrent with the onset of feeding behavior.

Preliminary observations on responses of embryonic and larval @entity27857 , XXXX , to neutral fraction biodegradation products of weathered Alaska North Slope oil.

@entity12360 :: ('MESH:C565532', 'Disease') :: ['water-soluble neutral fraction', 'WSF'] @entity137 :: ('MESH:D064420', 'Disease') :: ['Toxicity'] @entity27857 :: ('30724', 'Species') :: ['Pacific herring', 'Clupea pallasi'] @entity7294 :: ('CHEBI:24632', 'Chemical') :: ['hydrocarbon']
@entity27857 :: (30724,Species) :: ['Clupea pallasi']
