[In vitro toxicity of naturally occurring silica nanoparticles in C1 coal in bronchial epithelial cells].
OBJECTIVE
China's Xuan Wei County in Yunnan Province have the world's highest incidence of lung cancer in nonsmoking women-20 times higher than the rest of China. Previous studies showed, this high lung cancer incidence may be associated with the silica particles embedded in the production combustion from the C1 coal. The aim of this study is to separate the silica particles from production combustion from the C1 bituminous coal in Xuan Wei County of Yunnan Province, and study in vitro toxicity of naturally occurring silica particles on BEAS-2B.


METHODS
①Separating the silica particles from combustion products of C1 bituminous coal by physical method, observing the morphology by Scanning Electron Microscope, analysis elements by SEM-EDX, observed the single particle morphology by Transmission Electron Microscope, analyed its particle size distribution by Laser particle size analyzer, the surface area of silica particles were determined by BET nitrogen adsorption analysis; ②Cell viability of the experimental group (silica; naturally occurring), control group (silica; industrial produced and crystalline silica) was detected by assay used the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method, and the reactive oxygen species (ROS), lactate dehydrogenase (LDH) were determined after 24 h-72 h exposed to these particles.


RESULTS
①The physical method can separate silica particles from production combustion from the C1 bituminous coal, which have different size, and from 30 nm to 120 nm particles accounted for 86.8%, different morphology, irregular surface area and containing trace of aluminum, calcium and iron and other elements; ②Under the same concentration, the experiment group have higher toxicity on BEAS-2B than control groups.


CONCLUSIONS
Physical method can separate silica particles from production combustion from the C1 bituminous coal and not change the original morphology and containing trace; ②Naturally occurring silica nanoparticles have irregular morphology, surface area, and containing complex trace elements may has greater toxicity than the silica nanoparticle of industrial produced and crystalline silica.
Department of Cardiothoracic Surgery, the Third Affiliated Hospital of Kunming Medical University/the Tumor Hospital of Yunnan Province, Kunming 650118, China.
Guangjian
G
Li
Yunchao
Y
Huang
Yongjun
Y
Liu
Lv
L
Guo
Yongchun
Y
Zhou
Kun
K
Yang
Ying
Y
Chen
Guangqiang
G
Zhao
Yujie
Y
Lei
D001688:Biological Products / Q000737:chemistry / Q000633:toxicity*; D001980:Bronchi / Q000166:cytology*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003031:Coal / Q000032:analysis*; D004305:Dose-Response Relationship, Drug; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D053758:Nanoparticles / Q000633:toxicity*; D010316:Particle Size; D012822:Silicon Dioxide / Q000737:chemistry / Q000633:toxicity*; D013499:Surface Properties; D023382:Toxicity Tests, Acute
D001688:Biological Products; D003031:Coal; D012822:Silicon Dioxide; D007770:L-Lactate Dehydrogenase