Crude oil has multiple toxic effects in fish, particularly during their early life stages. Recent transcriptomics studies have highlighted a potential effect on cholesterol homeostasis and biosynthesis, but have not investigated effects on steroid hormones, which are biosynthetically downstream metabolites of cholesterol. We exposed zebrafish (Danio rerio) embryos and larvae to 3 concentrations of a high energy water accommodated fraction (HEWAF) of crude oil and measured effects on cholesterol and steroid hormones at 48 and 96 h post fertilization (hpf). HEWAF exposure caused a small decrease in cholesterol at 96 hpf but not 48 hpf. HEWAF-exposed larvae had higher levels of androstenedione, testosterone, estradiol, cortisol, corticosterone, and progesterone at 96 hpf compared to controls, while effects at 48 hpf were more modest or not present. 2-Methoxyestradiol was lower following HEWAF exposure at both time points. Dihydrotestosterone was elevated in one HEWAF concentration at 48 hpf only. Our results suggest that hormone imbalance may be an important toxic effect of oil HEWAF exposure despite no major effect on their biosynthetic precursor cholesterol.

原油对鱼类有多种毒性作用，尤其是在它们的早期生命阶段。最近的转录组学研究强调了对胆固醇稳态和生物合成的潜在影响，但尚未研究对类固醇激素的影响，类固醇激素是胆固醇的生物合成下游代谢物。我们暴露了斑马鱼 ( Danio rerio) 胚胎和幼虫到 3 种浓度的高能水容纳部分 (HEWAF) 的原油，并测量受精后 48 和 96 小时 (hpf) 对胆固醇和类固醇激素的影响。HEWAF 暴露导致胆固醇在 96 hpf 但不是 48 hpf 时略有下降。与对照相比，HEWAF 暴露的幼虫在 96 hpf 时具有更高水平的雄烯二酮、睾酮、雌二醇、皮质醇、皮质酮和黄体酮，而在 48 hpf 时的影响较为温和或不存在。在两个时间点，HEWAF 暴露后 2-甲氧基雌二醇均较低。一种 HEWAF 浓度的二氢睾酮仅在 48 hpf 时升高。我们的结果表明激素失衡可能是油 HEWAF 暴露的重要毒性作用，尽管对其生物合成前体胆固醇没有重大影响。