The Primary Effects of Embryonic Zebra fish (Danio rerio) Exposed to Iranian Heavy Crude Oil

Abstract

On 7th, December 2007, a barge carrying a crane collided with the oil tanker M/V Hebei Spirit, and 12,547 kl of crude oil were spilled from the tanker into the West coast of Korea. Three different kinds of crude oils (Iranian Heavy, KEC and U/Zkum) were spilled from the punctured tanks, respectively. To clarify the effects of the spilled oil on fish development, two laboratory studies were conducted. Zebrafish embryos (96 h post-fertilization) were exposed to the water-accommodated fraction (WAF) and oiled gravel effluent of Iranian Heavy Crude (IHC) oil for 48 h. Embryos were manually dechorionated and observed by a stereomicroscope and a compound microscope. Embryos were fixed in 4% phosphate-buffered paraformaldehyde and stained for CYP1A and myosin heavy chain. After 24 hr, several complex effects, including the edema and tail mutant were observed in zebrafish embryos exposed to IHC. The distribution of CYP1A in embryo was assessed by immunofluorescence. CYP1A immunofluorescence activity was showed significantly in the endothelium of head, epidermis and endocardium. Our results confirm that Zebra fish embryos exposed to the IHC may disrupt the cardiac function and shape of fish tail during development which is highly relevant for fitness and survival.