Naphthalene sulfonic acids (NSAs) are used as additives in lubricants, dyes, and greases and commonly act as surfactants in many industrial processes. The calcium salt of dinonyl NSA (calcium dinonylnaphthalenesulfonate; CaDNS) is listed among thousands of chemicals identified as priorities for assessment by the Government of Canada's Chemical Management Plan due to the limited toxicity data. The purpose of this study was two-fold: 1) to establish the toxicity of CaDNS to Western clawed frog (Silurana tropicalis) embryos and 2) to assess the sub-lethal effects and mechanisms of toxicity of CaDNS in amphibians through targeted gene expression and metabolite analyses. Frog embryos were exposed to water overlying sand spiked with a range of concentrations of CaDNS (17-1393 μg/g) over a 72-h period. Results indicated significantly higher mortality and presence of malformations in frog larvae exposed to over 672 μg/g CaDNS in the sand (14 ng/mL CaDNS in the water) compared to control treatments. An overall decrease in the glutathione redox cycle was observed, including decreases in relative mRNA levels of enzymes (glutathione S-transferase (gst), glutathione reductase (gsr), glutathione peroxidase (gpx)) and decreases in the glutathione (GSH) and glutathione disulfide (GSSG) metabolite concentrations. In addition, transcript levels of genes involved in antioxidant capacity and essential amino acid metabolites decreased significantly in embryos exposed to low levels of CaDNS. This is the first study to assess the toxicity of NSAs in amphibians, contributing important data to aid in the assessment of NSAs.

中文翻译：

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二壬基萘磺酸钙对西方爪蛙胚胎的亚致死作用。

萘磺酸（NSA）在润滑剂，染料和油脂中用作添加剂，在许多工业过程中通常用作表面活性剂。由于毒性数据有限，二壬基NSA的钙盐（二壬基萘磺酸钙； CaDNS）被列为数千种化学品，被加拿大政府化学品管理计划确定为需要评估的化学品。这项研究的目的是双重的：1）建立CaDNS对西方爪蛙（Siluranatropicis）胚胎的毒性，以及2）通过靶向基因表达和评估CaDNS对两栖动物的亚致死作用和毒性机制。代谢物分析。在72小时的时间内，将青蛙胚胎暴露在掺有一定浓度CaDNS（17-1393μg/ g）的沙子上的水中。结果表明，与对照处理相比，暴露于沙子中超过672μg/ g CaDNS（水中14 ng / mL CaDNS）的青蛙幼虫的死亡率和畸形的发生率更高。观察到了谷胱甘肽氧化还原循环的总体下降，包括酶（谷胱甘肽S-转移酶（gst），谷胱甘肽还原酶（gsr），谷胱甘肽过氧化物酶（gpx））的相对mRNA水平下降以及谷胱甘肽（GSH）和谷胱甘肽的下降二硫化物（GSSG）代谢产物浓度。此外，在暴露于低水平CaDNS的胚胎中，参与抗氧化能力和必需氨基酸代谢产物的基因的转录水平显着降低。这是评估NSA在两栖动物中的毒性的第一项研究，贡献了重要的数据来帮助评估NSA。