Twenty-eight-day inhalation toxicity study of silver nanoparticles in Sprague-Dawley rats.
The antibacterial effect of silver nanoparticles has resulted in their extensive application in health, electronic, and home products. Thus, the exposed population continues to increase as the applications expand. Although previous studies on silver dust, fumes, and silver compounds have revealed some insights, little is yet known about the toxicity of nano-sized silver particles, where the size and surface area are recognized as important determinants for toxicity. Thus, the inhalation toxicity of silver nanoparticles is of particular concern to ensure the health of workers and consumers. However, the dispersion of inhalable ambient nano-sized particles has been an obstacle in evaluating the effect of the inhalation of nano-sized particles on the respiratory system. Accordingly, the present study used a device that generates silver nanoparticles by evaporation/condensation using a small ceramic heater. As such, the generator was able to distribute the desired concentrations of silver nanoparticles to chambers containing experimental animals. The concentrations and distribution of the nanoparticles with respect to size were also measured directly using a differential mobility analyzer and ultrafine condensation particle counter. Therefore, the inhalation toxicity of silver nanoparticles was tested over a period of 28 days. Eight-week-old rats, weighing about 283 g for the males and 192 g for the females, were divided into 4 groups (10 rats in each group): a fresh-air control, a low-dose group (1.73 x 10(4)/cm3), a middle-dose group (1.27 x 10(5)/cm3), and a high-dose group (1.32 x 10(6) particles/cm3, 61 microg/m3). The animals were exposed to the silver nanoparticles for 6 h/day, 5 days/wk, for a total of 4 wk. The male and female rats did not show any significant changes in body weight relative to the concentration of silver nanoparticles during the 28-day experiment. Plus, there were no significant changes in the hematology and blood biochemical values in either the male or female rats. Therefore, the initial results indicated that exposure to silver nanoparticles at a concentration near the current American Conference of Governmental Industrial Hygienists (ACGIH) silver dust limit (100 microg/m3) did not appear to have any significant health effects.
Ji
Jun Ho
JH
Samsung Electronics Co. Ltd., Suwon, Korea.
Jung
Jae Hee
JH
Kim
Sang Soo
SS
Yoon
Jin-Uk
JU
Park
Jung Duck
JD
Choi
Byung Sun
BS
Chung
Yong Hyun
YH
Kwon
Il Hoon
IH
Jeong
Jayoung
J
Han
Beom Seok
BS
Shin
Jae Hyeg
JH
Sung
Jae Hyuck
JH
Song
Kyung Seuk
KS
Yu
Il Je
IJ
D000818:Animals; D001772:Blood Cell Count / Q000379:methods; D001835:Body Weight / Q000187:drug effects / Q000502:physiology; D005260:Female; D019570:Inhalation Exposure / Q000009:adverse effects; D008297:Male; D053768:Metal Nanoparticles / Q000008:administration & dosage* / Q000633:toxicity; D051381:Rats; D017207:Rats, Sprague-Dawley; D012834:Silver / Q000008:administration & dosage* / Q000633:toxicity; D013997:Time Factors; D014018:Tissue Distribution / Q000187:drug effects / Q000502:physiology
D012834:Silver