Subacute inhalation toxicity study of an ice-nucleation-active Pseudomonas syringae administered as a respirable aerosol to rats.
The inhalation toxicity of a commercial sample of an ice-nucleation-active Pseudomonas syringae (strain 31a) was evaluated by repetitively exposing rats to about 700 mg/m3 of an aerosol consisting of a suspension of 0.0008, 0.4 or 0.8 g/l of bacteria in water for 2 h per day, 5 days per week for 13-14 exposures. No mortality, moribundity or biologically significant differences in clinical signs, body weight, food consumption or clinical pathology were observed. Animals tested at 500 times (0.4 g/l) and 1000 times (0.8 g/l) the recommended ice-nucleation concentration (0.0008 g/l) exhibited concentration-dependent increased lung weights. Several animals exhibited enlarged tracheobronchial lymph nodes. The pulmonary responses observed are considered compatible with a mild irritant reaction. There was no evidence of bacterial infection. Animals tested at a concentration typical for the discharge mouth of a snow gun (0.0008 g/l) demonstrated no significant biological effect.
Goodnow
R A
RA
Genencor International, Inc., Rochester, NY 14650-3605.
Katz
G
G
Haines
D C
DC
Terrill
J B
JB
D000280:Administration, Inhalation; D000336:Aerosols; D000818:Animals; D001273:Atmosphere Exposure Chambers; D001426:Bacterial Proteins / Q000032:analysis; D001427:Bacterial Toxins / Q000008:administration & dosage / Q000633:toxicity*; D005260:Female; D008168:Lung / Q000187:drug effects / Q000473:pathology; D008198:Lymph Nodes / Q000187:drug effects / Q000473:pathology; D008297:Male; D011549:Pseudomonas; D051381:Rats; D011919:Rats, Inbred Strains
D000336:Aerosols; D001426:Bacterial Proteins; D001427:Bacterial Toxins