Abstract

Silver (nAg) and titanium dioxide nanoparticles (nTiO₂) are common engineered nanoparticles (ENPs) added into paint for their antimicrobial and whitening properties, respectively. Weathering of outdoor painted surfaces can release such ENPs, though little is known about the potential effects of released ENPs on aquatic species. The objective of this study was to characterize the toxicity of nAg and nTiO₂ released from painted panels using fish liver cells (CRL2643) and zebrafish embryos (OECD 236 embryotoxicity test). Cells and embryos were exposed to suspensions of pristine nAg or nTiO₂, panels (unpainted or painted with nAg or nTiO₂) or base paint, after sonication. Cell viability and gene expression were assessed using resazurin assay and qPCR, respectively, while embryo mortality and deformities were scored visually via microscopic examination. In the cell studies, both paint-released nanoparticles did not affect viability, but paint-released nAg resulted in differential expression of a few genes including gclc and ncf1. In embryos, paint-released nAg increased mortality and incidence of deformities, whereas paint-released nTiO₂ resulted in differential expression of several genes including gclc, ncf1, txnrd1, gpx1b, and cyp1c1 but without major phenotypic abnormalities. Comparing the two types of exposures, paint-released exposures affected both molecular (gene expression) and apical (embryotoxicity) endpoints, while pristine exposures affected the expression of some genes but had no apical effects. The differing effects of paint-released and pristine nanoparticle exposures suggest that further research is needed to further understand how paint coatings (and the products of their weathering and aging) may influence nanoparticle toxicity to aquatic organisms.

摘要

银 (nAg) 和二氧化钛纳米粒子 (nTiO ₂ ) 是常见的工程纳米粒子 (ENP)，分别添加到涂料中，因为它们具有抗菌和增白特性。室外涂漆表面的风化会释放此类 ENP，但对释放的 ENP 对水生物种的潜在影响知之甚少。本研究的目的是使用鱼肝细胞 (CRL2643) 和斑马鱼胚胎（经合组织 236 胚胎毒性试验）表征从涂漆面板释放的 nAg 和 nTiO _{2 的}毒性。细胞和胚胎暴露于原始 nAg 或 nTiO _{2 的}悬浮液中，面板（未涂漆或涂有 nAg 或 nTiO ₂) 或底漆，超声处理后。分别使用刃天青测定和 qPCR 评估细胞活力和基因表达，同时通过显微镜检查对胚胎死亡率和畸形进行视觉评分。在细胞研究中，两种油漆释放的纳米粒子都不会影响活力，但油漆释放的 nAg 导致一些基因的差异表达，包括gclc和ncf1。在胚胎中，油漆释放的 nAg 增加了死亡率和畸形的发生率，而油漆释放的 nTiO ₂导致了几个基因的差异表达，包括gclc、ncf1、txnrd1、gpx1b和cyp1c1但无重大表型异常。比较两种类型的暴露，油漆释放的暴露影响分子（基因表达）和顶端（胚胎毒性）终点，而原始暴露影响一些基因的表达但没有顶端影响。油漆释放和原始纳米颗粒暴露的不同影响表明，需要进一步研究以进一步了解油漆涂层（及其风化和老化的产物）如何影响纳米颗粒对水生生物的毒性。