title: Toxicity of colloidal silica nanoparticles administered orally for 90 days in rats.
abstract: This study was undertaken to investigate the potential toxicity and establish the no observed adverse effect level (NOAEL) and target organ(s) of negatively charged colloidal silica particles of different sizes, ie, SiO2 (EN20(-)) (20 nm) or SiO2 (EN100(-)) 2(100 nm), administered by gavage in Sprague-Dawley rats. After verification of the physicochemical properties of the SiO2 particles to be tested, a preliminary dose range-finding study and 90-day repeated dose study were conducted according to the Organisation for Economic Cooperation and Development test guideline. Based on the results of the 14-day dose range-finding study, a high dose was determined to be 2,000 mg/kg, and middle and low doses were set at 1,000 and 500 mg/kg, respectively. In the 90-day toxicity study, there were no animal deaths in relation to administration of SiO2 particles of either size. In addition, no treatment-related clinical changes or histopathological findings were observed in any of the experimental groups. Moreover, no difference in toxic effects from chronic exposure to SiO2 (EN20(-))(20 nm) or SiO2 (EN100(-)) (100 nm) was observed. The results of this study indicate that the NOAEL for SiO2 (EN20(-)) and SiO2 (EN100(-)) would most likely be 2,000 mg/kg, and no target organ was identified in rats of either sex.
authors.affiliation: Department of Biochemistry and Molecular Biology, Korea University Medical School and College, Seoul, Republic of Korea.
authors.forename: Yu-Ri
authors.initials: YR
authors.lastname: Kim
authors.affiliation: General Toxicology Team, Korea Testing and Research Institute, Seoul, Republic of Korea.
authors.forename: Seung-Young
authors.initials: SY
authors.lastname: Lee
authors.affiliation: Department of Biochemistry and Molecular Biology, Korea University Medical School and College, Seoul, Republic of Korea.
authors.forename: Eun Jeong
authors.initials: EJ
authors.lastname: Lee
authors.affiliation: Department of Biochemistry, University of Bath, Bath, UK.
authors.forename: Sung Ha
authors.initials: SH
authors.lastname: Park
authors.affiliation: General Toxicology Team, Korea Testing and Research Institute, Seoul, Republic of Korea.
authors.forename: Nak-won
authors.initials: NW
authors.lastname: Seong
authors.affiliation: General Toxicology Team, Korea Testing and Research Institute, Seoul, Republic of Korea.
authors.forename: Heung-Sik
authors.initials: HS
authors.lastname: Seo
authors.affiliation: General Toxicology Team, Korea Testing and Research Institute, Seoul, Republic of Korea.
authors.forename: Sung-Sup
authors.initials: SS
authors.lastname: Shin
authors.affiliation: General Toxicology Team, Korea Testing and Research Institute, Seoul, Republic of Korea.
authors.forename: Seon-Ju
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: General Toxicology Team, Korea Testing and Research Institute, Seoul, Republic of Korea.
authors.forename: Eun-Ho
authors.initials: EH
authors.lastname: Meang
authors.affiliation: General Toxicology Team, Korea Testing and Research Institute, Seoul, Republic of Korea.
authors.forename: Myeong-Kyu
authors.initials: MK
authors.lastname: Park
authors.affiliation: General Toxicology Team, Korea Testing and Research Institute, Seoul, Republic of Korea.
authors.forename: Min-Seok
authors.initials: MS
authors.lastname: Kim
authors.affiliation: Department of Microbiology, Wonju College of Medicine, Yonsei University, Gangwon, Republic of Korea.
authors.forename: Cheol-Su
authors.initials: CS
authors.lastname: Kim
authors.affiliation: Department of Microbiology, Wonju College of Medicine, Yonsei University, Gangwon, Republic of Korea.
authors.forename: Soo-Ki
authors.initials: SK
authors.lastname: Kim
authors.affiliation: Department of Dermatology, Korea University Medical School and College, Seoul, Republic of Korea.
authors.forename: Sang Wook
authors.initials: SW
authors.lastname: Son
authors.affiliation: Department of Life Science, Institute of Environmental Medicine for Green Chemistry, Dongguk University, Seoul, Republic of Korea.
authors.forename: Young Rok
authors.initials: YR
authors.lastname: Seo
authors.affiliation: Nonclinical Research Institute, Chemon Inc, Gyeonggi, Republic of Korea.
authors.forename: Boo Hyon
authors.initials: BH
authors.lastname: Kang
authors.affiliation: Toxicological Research Center, Hoseo University, Chungnam, Republic of Korea.
authors.forename: Beom Seok
authors.initials: BS
authors.lastname: Han
authors.affiliation: Department of Bionanotechnology, Gachon University, Gyeonggi, Republic of Korea.
authors.forename: Seong Soo A
authors.initials: SS
authors.lastname: An
authors.affiliation: College of Veterinary Medicine, Chungbuk National University, Chungbuk, Republic of Korea.
authors.forename: Beom-Jun
authors.initials: BJ
authors.lastname: Lee
authors.affiliation: Department of Biochemistry and Molecular Biology, Korea University Medical School and College, Seoul, Republic of Korea.
authors.forename: Meyoung-Kon
authors.initials: MK
authors.lastname: Kim
mesh_terms: D000284:Administration, Oral; D000818:Animals; D003102:Colloids / Q000008:administration & dosage / Q000737:chemistry / Q000633:toxicity; D053758:Nanoparticles / Q000008:administration & dosage / Q000737:chemistry / Q000633:toxicity; D019055:No-Observed-Adverse-Effect Level; D051381:Rats; D017207:Rats, Sprague-Dawley; D012822:Silicon Dioxide / Q000008:administration & dosage / Q000737:chemistry / Q000633:toxicity; D036401:Toxicity Tests, Chronic
chemical_list: D003102:Colloids; D012822:Silicon Dioxide
keywords: 90-day oral dose toxicity; no observed adverse effect level; particle size; silica nanoparticles