Parrott J L, Raine J C, McMaster M E, Hewitt L M
Water Science and Technology Directorate, Environment and Climate Change Canada, 867 Lakeshore Road, Burlington, Ontario, L7S 1A1, Canada.
Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, Saskatchewan, S7N 5B3, Canada.
Heliyon. 2019 Sep 25;5(9):e02509. doi: 10.1016/j.heliyon.2019.e02509. eCollection 2019 Sep.
In this study fathead minnow () embryo-larval stages were exposed to two oil sands tailings pond sediments which had previously been shown to decrease the survival of embryo-larval larval stages of walleye () and northern pike (). Fathead minnow are standard test species and we wanted to compare their sensitivity to the other two species. Fathead minnow larvae were exposed for 20 days (5 days in the egg stage and 15 days in the larval stage) with daily renewal of sediments and waters. Sediments contained polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs (APAHs). Results from an earlier study showed that Sediment 1 contained 173 μg/g total PAHs + APAHs (97 % alkylated), and sediment 2 contained 401 μg/g total PAHs + APAHs (95 % alkylated). Fathead minnow larvae exposed to oil sands tailings pond sediments had decreased survival, decreased weight, and increased deformities. Fathead minnow survival was unaffected at the embryo stage and at hatch. Most deaths occurred at the larval stages 1-8 days after hatching, showing the importance of exposing the fish for at least a week after hatch. Toxicity was seen at 0.2 g/L of sediment, which was equivalent to the addition of 35 and 80 μg total PAHs + APAHs to 1 L of overlying water for sediment 1 and 2, respectively. When compared to embryo-larval northern pike and walleye results from previous studies, all three species of fish responded more strongly to sediment 2 compared to sediment 1. For effects on lethality, fathead minnow were equally sensitive to pike, but walleye were 5-28 times more sensitive to the lethal effects of the sediments compared to both fathead minnow and pike. The study (and comparisons to our previous studies) shows the difference in sensitivity between a model laboratory species (fathead minnow) and some species of wild fish that are highly relevant to the oil sands area of Alberta.
在本研究中，黑头呆鱼（）的胚胎 - 幼体阶段暴露于两种油砂尾矿池沉积物中，此前的研究表明，这两种沉积物会降低大眼狮鲈（）和白斑狗鱼（）胚胎 - 幼体阶段的存活率。黑头呆鱼是标准测试物种，我们想比较它们与其他两个物种的敏感性。黑头呆鱼幼体暴露20天（卵期5天，幼体期15天），沉积物和水每天更新。沉积物中含有多环芳烃（PAHs）和烷基化多环芳烃（APAHs）。早期研究结果表明，沉积物1含有173μg/g的总PAHs + APAHs（97%为烷基化），沉积物2含有401μg/g的总PAHs + APAHs（95%为烷基化）。暴露于油砂尾矿池沉积物的黑头呆鱼幼体存活率降低、体重减轻且畸形增加。黑头呆鱼在胚胎阶段和孵化时的存活率未受影响。大多数死亡发生在孵化后1 - 8天的幼体阶段，这表明在孵化后至少将鱼暴露一周的重要性。在沉积物浓度为0.2g/L时观察到毒性，这分别相当于向1L上覆水中添加35μg和80μg的总PAHs + APAHs，对应沉积物1和沉积物2。与先前研究中北方梭子鱼和大眼狮鲈的胚胎 - 幼体结果相比，与沉积物1相比，所有三种鱼类对沉积物2的反应更强。对于致死效应，黑头呆鱼对梭子鱼的敏感性相同，但与黑头呆鱼和梭子鱼相比，大眼狮鲈对沉积物致死效应的敏感性高5 - 28倍。该研究（以及与我们先前研究的比较）表明了模式实验室物种（黑头呆鱼）与艾伯塔省油砂地区一些野生鱼类之间敏感性的差异。
