A plan to create solution-mined salt caverns for natural gas storage by discharging brine into the Shubenacadie River estuary poses a potential risk to an "endangered" stock of striped bass. Toxicity of brine made from both salt-core and artificial sea-salt "Instant Ocean" was assessed by 1-h acute toxicity tests at both 19 °C and 12 °C, the typical thermal range in June, post-spawning. The short test duration was justified given the rapid dilution of the brine in the macrotidal estuary. The median lethal concentration (LC50 1 h) 95% confidence intervals of salt-core brine at 19 °C for eggs was 51-60 parts per thousand (ppt); yolk-sac larvae 34-55 ppt; first-feeding stage larvae (6-8 mm total length, TL) 37-44 ppt, and 30-46 ppt for large larvae (14-20 mm TL). Among juveniles, the median lethal concentration was significantly higher compared to larvae: 51-58 ppt for early juveniles (4-cm fork length, FL) and 63-67 ppt for juveniles 12-cm FL. The toxicity of brine made from either Instant Ocean or salt-core was similar. At 12 °C, yolk-sac larvae salinity tolerance was 30% lower than at 19 °C, whereas other life stages exhibited a similar response to 12 °C and 19 °C. The threshold observed effect concentration (TOEC) of the salt-core ranged from 24.4 ppt on large larvae to 59.7 ppt on 12-cm juveniles. In conclusion, a very low direct threat to striped bass is estimated for the discharge of brine into the Shubenacadie River estuary.

中文翻译：

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盐穴盐水对条纹鲈（Morone saxatilis）生命早期的急性毒性。

通过将盐水排入舒贝纳卡迪河河口来创建用于天然气存储的溶液开采盐洞的计划，对条纹鲈“濒危”种群构成了潜在风险。由盐芯和人造海盐“即时海洋”制成的盐水的毒性通过在19℃和12℃（产卵后通常在6月的典型温度范围）下进行1小时急性毒性测试进行了评估。考虑到潮汐河口中盐水的快速稀释，测试时间短是合理的。蛋的盐芯盐水在19°C时的平均致死浓度（LC50 1小时）的95％置信区间为51-60千分之几（ppt）；卵黄囊幼虫34-55 ppt; 初生阶段的幼虫（总长6-8毫米，TL）为37-44 ppt，大型幼虫（14-20毫米TL）为30-46 ppt。在青少年中，与幼虫相比，中位致死浓度明显更高：早期幼虫（4 cm叉长，佛罗里达州）为51-58 ppt，而幼虫12 cm FL为63-67 ppt。由Instant Ocean或盐芯制成的盐水的毒性相似。在12°C下，卵黄囊幼虫的盐度耐受性比19°C下低30％，而其他生命阶段对12°C和19°C表现出相似的响应。盐核心的阈值观察效应浓度（TOEC）在大型幼虫上为24.4 ppt，在12厘米幼鱼上为59.7 ppt。总之，据估计，向舒贝纳卡迪河河口排放盐水对条纹鲈的直接威胁非常低。在12°C下，卵黄囊幼虫的盐度耐受性比19°C下低30％，而其他生命阶段对12°C和19°C表现出相似的响应。盐核心的阈值观察效应浓度（TOEC）在大型幼虫上为24.4 ppt，在12厘米幼鱼上为59.7 ppt。总之，据估计，向舒贝纳卡迪河河口排放盐水对条纹鲈的直接威胁非常低。在12°C下，卵黄囊幼虫的盐度耐受性比19°C下低30％，而其他生命阶段对12°C和19°C表现出相似的响应。盐核心的阈值观察效应浓度（TOEC）在大型幼虫上为24.4 ppt，在12厘米幼鱼上为59.7 ppt。总之，据估计，向舒贝纳卡迪河河口排放盐水对条纹鲈的直接威胁非常低。