Effects of the size and morphology of zinc oxide nanoparticles on the germination of Chinese cabbage seeds.
The toxicity of four zinc oxide nanoparticles (i.e., spheric ZnO-30, spheric ZnO-50, columnar ZnO-90, and hexagon rod-like ZnO-150) to the seed germination of Chinese cabbage (Brassica pekinensis L.) was investigated in this study. The results showed that zinc oxide nanoparticles (nano-ZnOs) did not affect germination rates at concentrations of 1-80 mg/L but significantly inhibited the root and shoot elongation of Chinese cabbage seedlings, with the roots being more sensitive. The inhibition was evident mainly during seed incubation rather than the seed soaking process. Both the production of free hydroxyl groups (·OH) and the Zn bioaccumulation in roots or shoots resulted in toxicity of nano-ZnOs to Chinese cabbage seedlings. The toxicity of nano-ZnOs was affected significantly by their primary particle sizes in the minimum dimensionality, but large columnar ZnO-90 and small spherical ZnO-50 had comparable toxicities. Therefore, both the particle size and morphology affected the toxicity of nano-ZnOs.
Key Laboratory of Water/Soil Toxic Pollutants Control and Bioremediation of Guangdong Higher Education Institutions, School of Environment, Jinan University, Guangzhou, 510632, People's Republic of China.
Lei
L
Xiang
Hai-Ming
HM
Zhao
Yan-Wen
YW
Li
Xian-Pei
XP
Huang
Xiao-Lian
XL
Wu
Teng
T
Zhai
Yue
Y
Yuan
Quan-Ying
QY
Cai
Ce-Hui
CH
Mo
D001937:Brassica / Q000187:drug effects / Q000502:physiology*; D018525:Germination / Q000187:drug effects*; D053758:Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D010316:Particle Size; D018517:Plant Roots / Q000187:drug effects / Q000502:physiology; D036226:Seedlings / Q000187:drug effects; D012639:Seeds / Q000187:drug effects / Q000502:physiology*; D012989:Soil Pollutants / Q000737:chemistry / Q000633:toxicity*; D015034:Zinc Oxide / Q000737:chemistry / Q000633:toxicity*
D012989:Soil Pollutants; D015034:Zinc Oxide