Research Article

Ethylene Oxide: Acute Four-Hour and One-Hour Inhalation Toxicity Testing in Rats

Table 4

Clinical observations, mortality rates, and day of death for female rats following 1-hour exposure to EO.

Exposure group (ppm)Clinical signsMortalityNumber found dead
Observation day
During exposureDuring three days of postexposure periodNumber dead/total0a12

4827 ppmAbsent startle reflexPerinasal wetness, pericular/perioral/perinasal encrustation, unkempt fur, decreased respiration rate, hypoactivity5/50b12

4202 ppmPeriocular/perinasal encrustation, unkempt fur, decreased respiration rate, hypoactivity, ataxia, tremors1/5041

3966 ppmUnkempt fur, decreased respiration rate, hypoactivity, ataxia, tremors2/5001

aDay 0 is exposure day. Days 1 and 2 are days following exposure day.
bNumber of animals found dead on a particular day.