Multiple Tumors in Female Germfree Inbred Albino Mice Exposed to Bedding Treated With Ethylene Oxide<xref ref-type="fn" rid="FN2">2</xref>

Abstract

Germfree inbred albino mice were accidentally placed, for 150 days, on ground corncob bedding treated with ethylene oxide by the manufacturer. All the males died with massive hemorrhages in the thoracic and abdominal cavities, multiple hemorrhages in other sites, failure of the blood to clot, and jaundice. These effects confirm the results of Allen et al. [Nature (London) 193: 387–388, 1962], with conventional inbred mice. Few females were so affected. The first indication of a disturbance in the colony was failure to reproduce. The surviving, exposed females were held for observation. Over 90 percent of them, 400 to 900 days old, developed tumors of various kinds and in various sites. The ovaries were abnormal in almost all the animals examined. Graafian follicles and corpora lutea were rarely found. The history of the colony before exposure to ground corncob bedding treated with ethylene oxide, but in contact with nontreated ground corncobs from the same source, showed excellent reproduction and no tumors in either males or females up to 600 days of age. The blood-clotting time of these nonexposed mice and the blood picture were within the normal range for germfree animals.