Environmental and Molecular Mutagenesis - Legacy Tobacco ...

nutber of surviving fetuses decreased significantly with increases in irradiation
dose, while resorption rsbes increased . Vfien miee were irradiated for 5 consecutive
days during the preiu+plantation period, the number of surviving fetuses was less than
in controls but litter weights increased faster within one month of birth, and mice
fran treated groups remained larger than those from control during 1h years observation
. The carcinogenic effect of irradiation to embryos showed an incidence of
leukemia 4 .9 times higher in treated versus control animals . Studies of irradiation
induced malformations and carosnogegenesis were also conducted by observing inmediate
and late effects of single or fractionated low dose irradiations . The nssnber of
living fetuses was significaritly reduoed'with increasing radiation dose . The frequency
of rnalfornmations in external appearance increased with radiation doses . The imnediate
ef :ects in the single irradiation group were different fran those in the fractionated
irradiation groups . In general, all effects fraa single irrad3ati .ans were more significant
than those in the fractionated irradiation group, except for the frequency
of cranioschisis . Litters of mice in the fractionated irradiation group were observed
for late effects for 2 years . Litter weights were lower than in controls and the incidenee
of leukania was 2 .5 times higher in the treated group . Late effects were also
studied after 50R of irradiation given at 13-17 days gestation . Litter weights were
lpwer . ThP incidence of tumr was 8 times higher .
671
L .-T . ., ..F n, T', ;="'T~?TY nF L' CTDI!(- :
Lh^u '-hu-,`Zhan~ J+a, -5{a Shu-Zheng, Lfa~Cu+-e,?nd L+an X+n,-3uan ;
health and ;nt+-ez+damjc Center -f Henan =r-v{nce, Zhan3zh-u, P .RC .
Jan-derni ]uc+dun, kjn•.i -f tra~+t+-nat Ch+ne :e med+c+nes, had been
used as a t-n+c f-r th-usands -r" ye,rs . T- evaluate tha Wh-les-mene~!s -f
3d•±