“…In contrast, cancer bioassay data collected in rats for ethylene at 300, 1,000, and 3,000 ppm demonstrated no marked change in tumors of any kind (Hamm, Guest, and Dent 1984). Levels of HEV, which reflect total exposure to ethylene oxide (via all pathways) were measured for rats exposed to ethylene oxide or to ethylene under conditions similar to those corresponding to the rat cancer bioassays (Filser et al 2013), as well as in unexposed control animals (Walker et al 1993(Walker et al , 2000.…”