Savannah River Ecology Laboratory, University of Georgia, Aiken, South Carolina, USA.
Eugene P. Odum School of Ecology, University of Georgia, Athens, Georgia, USA.
Environ Toxicol Chem. 2022 Dec;41(12):2999-3006. doi: 10.1002/etc.5481. Epub 2022 Oct 25.
The ability of an organism to cope with environmental stressors varies across the life span because of developmental stage-specific responses and age-related functional declines. In the present study, we examined the effect of age on acute copper toxicity in Japanese medaka (Oryzias latipes). We first determined the median lethal concentration (LC50) at 96 h for embryos, 7-day-old fry, and 6-month-old medaka. Embryos were exposed to 0, 15, 30, 60, 125, 250, and 500 ppb CuSO through hatching. Fry were exposed to 0, 20, 50, 75, 100, 150, 250, and 500 ppb CuSO for 96 h. Adult fish were exposed to 0, 100, 150, 200, 250, and 300 ppb CuSO for 96 h. The 96-h LC50 was 804 ppb for embryos, 262 ppb for embryonically exposed larvae, 60.3 ppb for 7-day-old fry, and 226 ppb for adults. We then challenged cohorts of fish aged 2, 3, 5, 6, 7, 8, 9, 10, 11, 13, 14, 15, and 16 months with a 225-ppb CuSO exposure to determine the acute toxicity across the life span. The fish exhibited a bimodal tolerance to copper, with tolerance peaking in 2- and 3-month-old fish and again at 10 and 11 months of age. Our data demonstrate that copper sensitivity is dynamic throughout the medaka life span and may be influenced by trade-offs with reproduction. Environ Toxicol Chem 2022;41:2999-3006. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
生物体应对环境胁迫的能力因发育阶段特异性反应和与年龄相关的功能下降而在整个生命周期中有所不同。在本研究中，我们研究了年龄对日本青鳉（Oryzias latipes）急性铜毒性的影响。我们首先确定了胚胎、7 日龄幼鱼和 6 月龄青鳉在 96 小时时的半致死浓度（LC50）。胚胎在孵化过程中暴露于 0、15、30、60、125、250 和 500 ppb CuSO4 中。幼鱼在 96 小时内暴露于 0、20、50、75、100、150、250 和 500 ppb CuSO4 中。成鱼在 96 小时内暴露于 0、100、150、200、250 和 300 ppb CuSO4 中。胚胎的 96 小时 LC50 为 804 ppb，胚胎暴露的幼鱼为 262 ppb，7 日龄幼鱼为 60.3 ppb，成鱼为 226 ppb。然后，我们用 225 ppb CuSO4 暴露挑战年龄为 2、3、5、6、7、8、9、10、11、13、14、15 和 16 个月的鱼群，以确定整个生命周期的急性毒性。这些鱼对铜表现出双峰耐受，在 2 月龄和 3 月龄的鱼中耐受性最高，在 10 月龄和 11 月龄的鱼中再次达到峰值。我们的数据表明，铜敏感性在青鳉的整个生命周期中是动态的，可能受到与繁殖权衡的影响。环境毒理学与化学 2022；41:2999-3006。© 2022 作者。环境毒理学与化学由 Wiley Periodicals LLC 代表 SETAC 出版。
