A METHOD OF EXPOSING FISH TO WATER-ACCOMMODATED FRACTIONS OF OIL

Abstract

ABSTRACT The purpose of this study was to determine how to expose rainbow trout to water-accommodated fractions (WAF) from oil, for 96-hour acute lethality testing. Oxygen levels and WAF loss were monitored for a variety of exposure, aeration and fish loading density combinations. Aeration is needed, but the normal aeration rate (NAR) of 6.5 ± 1 mL air/L test solution/minute can be reduced to 1/10 NAR. Also, open and loosely sealed bags with an NAR exhibited a 90% WAF loss in the first 24 hours, compared with a 30% WAF loss by loosely sealed bags with 1/10 NAR. The latter method is therefore preferred for the static exposure of rainbow trout to WAF.