Abstract:
This study characterized and investigated the toxicity of two multi-walled carbon nanotubes (MWCNT) NM-401 and NM-403 at 60 and 180 µg after four repeated intratracheal instillations; follow-up times were 3, 7, 30, and 90 days after the last instillation. NM-401 was needle-like, long, and thick, while NM-403 was entangled, short, and thin. Both MWCNT types induced transient pulmonary and systemic alterations in renal function and oxidative lipid damage markers in recent times. Animals showed general toxicity in the immediate times after exposures, in addition to increased pulmonary LDH release at day 3. In further times, decreased liver and kidney relative weights were noted at higher MWCNT doses. Lung histological damages included pulmonary fibrosis, for both MWCNT types, similarly to asbestos; single liver and kidney histological alterations were present. Repeated instillations led to persistent pulmonary damage at low doses, and possibly the extrapulmonary effects may be associated with the consecutive exposures.
摘要:
这项研究表征并研究了在四次重复气管内滴注后60和180µg的两种多壁碳纳米管(MWCNT)NM-401和NM-403的毒性;最后一次滴注后的随访时间为3、7、30和90天。NM-401是针状的,长,又厚,当NM-403被纠缠时,短,又瘦。最近,两种MWCNT类型均诱导了肾功能和氧化脂质损伤标志物的短暂性肺和全身性改变。动物在接触后立即表现出一般毒性,除了第3天肺LDH释放增加。在进一步的时代,在较高的MWCNT剂量下注意到肝脏和肾脏相对重量降低。肺组织学损害包括肺纤维化,对于这两种MWCNT类型,与石棉相似;存在单个肝脏和肾脏组织学改变。反复滴注导致低剂量持续的肺损伤,肺外影响可能与连续暴露有关。