Pulmonary and cardiovascular responses of rats to inhalation of silver nanoparticles.
Exposure to wet aerosols generated during use of spray products containing silver (Ag) has not been evaluated. The goal was to assess the potential for cardiopulmonary toxicity following an acute inhalation of wet silver colloid. Rats were exposed by inhalation to a low concentration (100 μg/m(3) ) using an undiluted commercial antimicrobial product (20 mg/L total silver; approximately 33 nm mean aerodynamic diameter [MAD]) or to a higher concentration (1000 μg/m(3)) using a suspension (200 mg/L total silver; approximately 39 nm MAD) synthesized to possess a similar size distribution of Ag nanoparticles for 5 h. Estimated lung burdens from deposition models were 0, 1.4, or 14 μg Ag/rat after exposure to control aerosol, low, and high doses, respectively. At 1 and 7 d postexposure, the following parameters were monitored: pulmonary inflammation, lung cell toxicity, alveolar air/blood barrier damage, alveolar macrophage activity, blood cell differentials, responsiveness of tail artery to vasoconstrictor or vasodilatory agents, and heart rate and blood pressure in response to isoproterenol or norepinephrine, respectively. Changes in pulmonary or cardiovascular parameters were absent or nonsignificant at 1 or 7 d postexposure with the exceptions of increased blood monocytes 1 d after high-dose Ag exposure and decreased dilation of tail artery after stimulation, as well as elevated heart rate in response to isoproterenol 1 d after low-dose Ag exposure, possibly due to bioavailable ionic Ag in the commercial product. In summary, short-term inhalation of nano-Ag did not produce apparent marked acute toxicity in this animal model.
Health Effects Laboratory Division (HELD), National Institute for Occupational Safety and Health (NIOSH), Centers for Disease Control and Prevention (CDC), 1095 Willowdale Rd. (M/S 2015), Morgantown, WV 26505, USA. jur6@cdc.gov
Jenny R
JR
Roberts
Walter
W
McKinney
Hong
H
Kan
Kristine
K
Krajnak
David G
DG
Frazer
Treye A
TA
Thomas
Stacey
S
Waugh
Allison
A
Kenyon
Robert I
RI
MacCuspie
Vincent A
VA
Hackley
Vincent
V
Castranova
D055371:Acute Lung Injury / Q000139:chemically induced* / Q000378:metabolism; D000280:Administration, Inhalation; D000336:Aerosols; D000818:Animals; D000890:Anti-Infective Agents / Q000493:pharmacokinetics / Q000633:toxicity*; D001158:Arteries / Q000187:drug effects / Q000503:physiopathology; D002316:Cardiotonic Agents / Q000494:pharmacology; D002319:Cardiovascular System / Q000187:drug effects*; D003102:Colloids; D006439:Hemodynamics; D007545:Isoproterenol; D008168:Lung / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D053768:Metal Nanoparticles / Q000633:toxicity*; D009638:Norepinephrine; D010316:Particle Size; D051381:Rats; D017207:Rats, Sprague-Dawley; D018030:Silver Compounds / Q000493:pharmacokinetics / Q000633:toxicity*; D014662:Vasoconstrictor Agents
D000336:Aerosols; D000890:Anti-Infective Agents; D002316:Cardiotonic Agents; D003102:Colloids; D018030:Silver Compounds; D014662:Vasoconstrictor Agents; D007545:Isoproterenol; D009638:Norepinephrine