以秀麗隱桿線蟲做為模式生物評估奈米二氧化鈦之生態環境風險

Ecological risk evaluation of titanium dioxide nanoparticles in Caneorhabdities elegans

嚴信(Hsin Yen)

指導教授 ： 廖秀娟

國立臺灣大學/生物資源暨農學院/生物環境系統工程學研究所/碩士(2014年)

https://doi.org/10.6342/NTU.2014.11228

摘要

近年來，奈米粒子已被視為潛在的新興環境污染物。而其中，奈米二氧化鈦為現今最廣為使用的奈米粒子之一。奈米二氧化鈦會影響生物體之神經系統以及生殖系統外，更有致癌的可能性，可能會對人類健康及生物造成潛在風險。過去已有研究證實，奈米二氧化鈦會對環境生物產生致死之風險。但對於非致死毒性效應之風險過去鮮少被探討。因此，本研究利用秀麗隱桿線蟲(Caenorhabditis elegans)作為奈米二氧化鈦風險評估之模式生物，探討奈米二氧化鈦之環境神經毒性風險以及族群風險。本研究結果顯示，較小粒徑(4 nm)的奈米二氧化鈦之暴露會造成更大的神經毒性以及氧化壓力之風險。同時，本研究也證實，高濃度奈米二氧化鈦的暴露會造成C. elegans死亡、成長抑制和繁殖系統損害等不利效應。藉由模式擬合該毒理數據，結果發現C. elegans的族群成長率隨奈米二氧化鈦暴露濃度上升會有明顯下降之現象。此外，本研究亦更進一步指出，當C. elegans族群受奈米二氧化鈦之危害，其子代族群會承受更為嚴重之風險。本研究結果可應用於未來實際調查現地生物之環境風險

關鍵字

奈米二氧化鈦 ； 秀麗隱桿線蟲 ； 環境神經毒風險 ； 族群風險

並列摘要

Nanoparticles (NPs) have been considered as potential emerging contaminants in the environment. Titanium dioxide nanoparticles (TiO2-NPs) are one of the most used NPs in the world. TiO2-NPs caused toxic effect on the nervous system and the reproductive system of the organisms. In addition TiO2-NPs might induce possible carcinogenesis. Thus, TiO2-NPs might induce potential risks to human health and other organisms. Several studies have demonstrated that TiO2-NPs caused lethality to the environment organisms. However, for the potential risk of sub-lethal effect of TiO2-NPs have not assessed. In the present study, Caenorhabditis elegans (C. elegans) was used as risk assessment model organism to assess the potential neurotoxic risk and population risk upon TiO2-NPs exposure. The results showed that smaller size of TiO2-NPs (4 nm) exposure resulted in higher neurotoxic and oxidative stress risk. Moreover, the results showed that TiO2-NPs exposure caused C. elegans mortality, growth inhibition and reproduction decline. By fitting the toxicological data, modeling result showed that population growth rates of C. elegans were decreased as the concentration of TiO2-NPsincrease. In addition, when C. elegans populations were exposed of TiO2-NPs, the progeny population exhibited high risk of population decline. Results from this study can provide valuable information for environmental risk assessment.

並列關鍵字

Titanium dioxide nanoparticles ； Caenorhabditis elegans ； neurotoxic risk ； population risk

參考文獻

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