Abstract
Increased frequencies of primary brain tumours were seen in male and female F-344 rats exposed to 100 or 33 ppm ethylene oxide (EO) vapour (for 6 hr daily on 5 days/wk for up to 2 yr) but no such increase was seen in rats similarly exposed to 10 ppm EO. The tumours that were seen (glial-cell tumours, granular-cell tumours and malignant reticuloses) were similar in appearance to those that develop spontaneously in F-344 rats, but the tumours associated with EO exposure at levels of 100 or 33 ppm were larger, and in at least six cases were thought to be the primary cause of death. Only two of the 23 tumours seen microscopically were detected by gross examination at necropsy, and brain weights were of minimal value in predicting the presence of tumours. Only three animals demonstrated abnormal neurological signs. These findings point to the need for thorough microscopic examination of the brains of rodents in chronic studies.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
