Appeal from a decision awarding benefits for death from acute myeloblastie leukemia, found due to exposure to radiation. The case was before us on a prior appeal (18 A D 2d 952). The record discloses that decedent was exposed to radiation for a substantial part of two periods and also at other times in various amounts. The testimony of the medical experts is emphatic that there is really no “ threshold ” or “ safe ” dosage of radiation because at the present stage of scientific knowledge it cannot be ascertained exactly what effects radiation has on the human body. It is also admitted that each individual reacts differently to exposure to radiation. The award is supported by substantial evidence and by the presumptions (Workmen’s Compensation Law, § 3, subd. 2; § 47), especially so in view of decedent’s good health prior to his employment. Decision affirmed, with costs to the Workmen’s Compensation Board. Gibson, P. J., Herlihy, Reynolds and Taylor, JJ., concur.