- Radiootoliosic Studies 13966 . Ietimate Revised Pos. LOSY Estimate Revised AMOUNT LO Pos. $154, COO increase Amount 17 Pos. $354,000 Amount +7 +$200, 000 Supportive radiobiciogical investigations have the following objectives: Obfective i: To provide information on the distribution and dose of wne emoryonic thyroid and its nossibie teratogenic effect. Objective &: To evaluate the frequency and persistence of chromosome aberrations waAat are croduced in thyroid tissue as a function of dose compar- ing X-ray and ~327 exposures and to devermine tne association oF observed enromoscme abnormalities to the induction of thyroid tumors. Cojective 2: To determine the efrent of zonadal and pituitary normones the incucvion anc development of uiyroid vumors afver radiation exnosure. Cojiective =: igenesis. To determine age urwnsitivivy in radiation thyroid tumor- O ~- ty Jay MATH Tae suidies are conducted using chinese namsters, rats, and dogs under controlled and known radiation exposure situations. Work will be conducted at existing laboratory facilities of tne Divisicn ana tae Collasorative Radiological Health Animel Research Laboratory at Colorado State College. Tentative pians are to coordinate the in-uterine phase of wnis study at Colorado with relaved experiments planned at tne University of California (Davis). 1966 L967 Hstimate Revised Pos. AMOUNT 2 Trerease SSstimate Revised Pos. smount 340,000 8 _ S240, 0CO Ros. Amount +6 +$200, 000 py ode tO aa wore wen sok ne 2. a 7 wet anvestigction ofa 7 Environmental Colvresens in Study Posvulations Tyee me a aosence oF Known goitrogenic . Summary: are under leapt wpa t daay mt wrt 4 oe sey? : es on 3 a Bavircemental studies will ce undertaken in the same locales s et svucy i7 ie including minerals in w ver, milk, 5 acy + a =} thar to idenvify major dietary constivuents, and rood, goitrogens in foods, as well as potential soltrogenic Tactors related to pecullarities of ‘the region or habits and needs of the study sopuletions. Efforts will be made to esvablish the extent oF exposure oF selected grcouss and individuals to any goltrogenic Pactors identisied.