We said in Morrison v. Burlington Industries, 304 N.C. 1, 282 S.E. 2d 458 (1981):
Except as to questions of jurisdiction, the rule is that the findings of fact made by the Commission are conclusive on appeal when supported by competent evidence. This is so even though there is evidence to support a contrary finding *678of fact. Morrison v. Burlington Industries, 301 N.C. 226, 271 S.E. 2d 364 (1980); Inscoe v. Industries, Inc., 292 N.C. 210, 232 S.E. 2d 449 (1977); Anderson v. Construction Co., 265 N.C. 431, 144 S.E. 2d 272 (1965); Rice v. Chair Co., 238 N.C. 121, 76 S.E. 2d 311 (1953); Henry v. Leather Co., 231 N.C. 477, 57 S.E. 2d 760 (1950). The appellate court does not retry the facts. It merely determines from the proceedings before the Commission whether sufficient competent evidence exists to support its findings of fact. Moses v. Bartholomew, 238 N.C. 714, 78 S.E. 2d 923 (1953).
Id. at —, 282 S.E. 2d at 463. We first determine whether there is competent evidence to support the findings of the Industrial Commission.
All pertinent portions of the evidence in this case are set out in the statement of facts. The overwhelming thrust of that evidence is to the effect that Mr. Walston suffers from chronic bronchitis, pulmonary emphysema, asthma, “possible byssinosis,” and chronic pulmonary fibrosis. When asked whether plaintiffs respiratory diseases and breathing problems were due to causes and conditions peculiar to his employment and to which the general public is not equally exposed, Dr. Williams said:
I don’t think we could exclude the possibility, if it were indeed dusty in the cloth room where this man was employed, that it could have played a role in the etiology of his problems. . . . The cloth room is reputed to be a fairly clean area of the mill as far as dust is concerned. ... A fairly dust-free environment.
When asked whether plaintiff’s exposure to cotton dust for thirty years in his employment could have caused his respiratory disease, Dr. Williams replied:
My opinion is that it could possibly have played a role in the causation of his pulmonary problems. . . . [I]f it did, it would be more likely a contributory role rather than a single cause and effect relationship. [Emphasis supplied.]
Dr. Williams further testified that plaintiff’s cigarette smoking would “most likely play a part in his pulmonary disability,” adding that plaintiff did not have a classical history of byssinosis which raised doubts in his mind as to whether plaintiff had byssinosis in the first place. The doctor was unable to give per*679centages regarding the relative contributions to plaintiffs lung disease by (1) his exposure to cotton dust and (2) his cigarette smoking.
It thus appears that substantially all of the competent medical evidence tends to show that plaintiff, suffers from several ordinary diseases of life to which the general public is equally exposed, none of which have been proven to be due to causes and conditions which are characteristic of and peculiar to any particular trade, occupation or employment and none of which have been aggravated or accelerated by an occupational disease. This is fatal to plaintiffs claim. G.S. 97-53(13); Anderson v. Motor Co., 233 N.C. 372, 64 S.E. 2d 265 (1951).
There is little, if any, evidentiary support for the statement in the decision of the Court of Appeals that
the diseases responsible for plaintiffs disability satisfy the statutory requirements of compensability. Its [the testimony’s] clear import is that: (1) the environmental conditions which characterize plaintiffs place of employment are also substantial factors in causing the diseases of which plaintiff suffers; and (2) plaintiff by virtue of his employment is exposed to such irritants in greater quantities than persons otherwise employed.
(Emphasis supplied.) See 49 N.C. App at 309, 271 S.E. 2d at 521. The expert medical testimony does not establish that plaintiff has an occupational disease. While smoking “was almost certain[ly] the primary etiologic agent,” there was only a “possibility” that any portion of plaintiffs disability was caused by the inhalation of cotton dust. Such evidence supports the findings and conclusions of the Commission that plaintiff failed to meet his burden of proof, i.e., failed to prove that he had an occupational disease defined in G.S. 97-53(13). A mere possibility of causation is neither “substantial” nor sufficient. It must be shown that the disease in question is an occupational disease, ie., a disease which is due to causes and conditions which are characteristic of and peculiar to claimant’s trade, occupation or employment as distinguished from an ordinary disease of life to which the general public is equally exposed outside of the employment. G.S. 97-53(13); Duncan v. Charlotte, 234 N.C. 86, 66 S.E. 2d 22 (1951). Disability caused by and resulting from a disease is compensable when, and only when, *680the disease is an occupational disease, or is aggravated or accelerated by an occupational disease, or by an injury by accident arising out of and in the course of the employment. G.S. 97-53(13); Morrison v. Burlington Industries, — N.C. —, 282 S.E. 2d 458 (1981); Booker v. Medical Center, 297 N.C. 458, 256 S.E. 2d 189 (1979); Anderson v. Motor Co., 233 N.C. 372, 64 S.E. 2d 265 (1951); Henry v. Leather Co., 231 N.C. 477, 57 S.E. 2d 760 (1950). Here, the evidence does not satisfy those requirements because the requisite causal connection between plaintiffs diseases and his employment, as required by G.S. 97-53(13), has not been proven. Rather, it amply supports the Commission’s findings that plaintiff does not have an occupational disease and his shortness of breath is due to pulmonary emphysema and chronic bronchitis. The findings are therefore conclusive on appeal.
For the reasons stated the decision of the Court of Appeals is reversed. The case is remanded to that court for further remand to the Industrial Commission for reinstatement of its award denying compensation.
Reversed and remanded.
Justices EXUM and CARLTON concur in the result.