Biopersistence of silver nanoparticles in tissues from Sprague-Dawley rats.
Silver nanoparticles are known to be distributed in many tissues after oral or inhalation exposure. Thus, understanding the tissue clearance of such distributed nanoparticles is very important to understand the behavior of silver nanoparticles in vivo. For risk assessment purposes, easy clearance indicates a lower overall cumulative toxicity. Accordingly, to investigate the clearance of tissue silver concentrations following oral silver nanoparticle exposure, Sprague-Dawley rats were assigned to 3 groups: control, low dose (100 mg/kg body weight), and high dose (500 mg/kg body weight), and exposed to two different sizes of silver nanoparticles (average diameter 10 and 25 nm) over 28 days. Thereafter, the rats were allowed to recover for 4 months. Regardless of the silver nanoparticle size, the silver content in most tissues gradually decreased during the 4-month recovery period, indicating tissue clearance of the accumulated silver. The exceptions were the silver concentrations in the brain and testes, which did not clear well, even after the 4-month recovery period, indicating an obstruction in transporting the accumulated silver out of these tissues. Therefore, the results showed that the size of the silver nanoparticles did not affect their tissue distribution. Furthermore, biological barriers, such as the blood-brain barrier and blood-testis barrier, seemed to play an important role in the silver clearance from these tissues.
Institute of Nanoproduct Safety Research, Hoseo University, 165 Sechul-ri, Baebang-myun, Asan 336-795 South Korea. u1670916@chollian.net.
Ji Hyun
JH
Lee
Yong Soon
YS
Kim
Kyung Seuk
KS
Song
Hyun Ryol
HR
Ryu
Jae Hyuck
JH
Sung
Jung Duck
JD
Park
Hyun Min
HM
Park
Nam Woong
NW
Song
Beom Soo
BS
Shin
Daniel
D
Marshak
Kangho
K
Ahn
Ji Eun
JE
Lee
Il Je
IJ
Yu
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D003102:Colloids; D004305:Dose-Response Relationship, Drug; D005260:Female; D006207:Half-Life; D008297:Male; D008657:Metabolic Clearance Rate; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000633:toxicity / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D009929:Organ Size / Q000187:drug effects; D009928:Organ Specificity; D010316:Particle Size; D051381:Rats; D017207:Rats, Sprague-Dawley; D012834:Silver / Q000737:chemistry / Q000493:pharmacokinetics* / Q000633:toxicity; D014018:Tissue Distribution
D003102:Colloids; D012834:Silver