Biological Responses in Rats Exposed to the Hebei Spirit Oil Spill Constituents

Abstract

Background : The Hebei Spirit Oil Spill, the largest oil spill in Korea, occurred in December 2007,. Many crude-oil components are well-known potential carcinogens and developmental toxicants. Aims : To evaluate the acute to chronic effects of crude oil exposure on hematological and blood biochemical toxicities. Methods : Sprague-Dawley rats were given oral doses of 0, 50 or 100 mg/kg BW/day of Iranian heavy crude oils for four weeks. Results : In the acute phase of exposure (one day after four weeks of oil treatment), decrease in the weight of thymus, serum level of interferon gamma (IFN-?), superoxide dismutase (SOD) and catalase activities in liver or kidney was found, and increase in the weight of adrenal gland occurred after the oral administration of crude oil. In body weight, histopathological examination, hematological, and blood biochemical analyses in the acute phase of exposure, there were no significant differences among the experimental groups. In the subchronic and chronic phase of exposure (two months and six months after four weeks of oil treatment), the changes of biomarkers were normalized except for the indicators of oxidative stress. Conclusions : Our findings show that the bioassay on the indicators of oxidative stress is a sensitive method for determining exposure to crude oil in rats.