Appeal from a decision and award of the Workmen’s Compensation Board. The medical proof is that claimant, who is a truck driver, has a peripherovascular disease which impairs the circulation. The proof also is that a person so handicapped is especially susceptible to exposure *620to cold. Claimant testified that while standing on the job on a cold day his “ toes became frozen ”. His foreman testified that claimant “ said his feet was cold ” and that “ he complained of his feet ”. The following day, claimant testified, he noticed discoloration in his toes which he tried to treat at home. He was taken some weeks later to a hospital where the condition was diagnosed as gangrene requiring amputation. The medical proof of the gangrene and its cause in the peripherovascular disease is clear in the record. What is arguable is whether there is proof that it was adversely affected by exposure to the cold on the job. The proof of claimant’s sensations and observations is entirely competent and seems credible. The discoloration immediately following the exposure to the cold where no discoloration had been observed before exposure could be found to have been caused by the exposure, whether this is technically “frostbite” or not. No physician observed “frostbite” or effects of cold as such, separated from the effects of the circulatory disease, but if exposure to cold in such a situation could adversely affect the physical condition and induce gangrene, and if exposure with some changes observable by a layman is credibly established to the satisfaction of the board and regarded by medical witnesses to have affected the disease if they existed, we think there is substantial evidence to find they existed and that they had the medical effect described. Award affirmed, with costs to the Workmen’s Compensation Board. Foster, P. J., Bergan, Coon and Gibson, JJ., concur.