Claimant filed a claim alleging that he contracted an occupational disease as defined in ORS 656.802 (Ilia)1. The referee found that claimant had suffered a compensable occupational disease involving his lungs. The Workers’ Compensation Board reversed, finding that the claimant had not sustained his burden of proof. The circuit court affirmed the Board and claimant appealed.
The only issue on appeal is whether claimant’s physical condition is causally related to his employment as an automobile spray painter, an occupation he performed for over 25 years. The resolution of this question lies outside the scope of lay persons’ knowledge and must be left to expert medical opinion, which the trier of fact must weigh and consider. Iverson v. SAIF, 28 Or App 789, 561 P2d 651 (1977).
Dr. Eugene Kazmierski, an internist who was claimant’s treating physician, began seeing claimant in 1971 for general care. In September 1975 claimant’s x-rays disclosed fuzzy nodular areas that were diagnosed by Dr. John W. Loomis, a radiologist, as "* * * [lying] between healed tuberculosis or other granulomatous disease, and siderosis or pneumoconiosis, possibly disease due to chronic inhalation of dust as in Farmer’s lung.” Although claimant’s condition was asymptomatic, Dr. Kazmierski encouraged claimant to discontinue his employment as a spray painter, which he did on October 23, 1975. Dr. Kazmierski indicated that he felt claimant’s condition might be an allergic response to chronic inhalation of chemical agents in the spray paint, but he did not rule out sarcoidosis, a disease of unknown etiology.
*24At the hearing before the referee Dr. Kazmierski testified that claimant was suffering from nodular pulmonary fibrosis, most likely talc pneumoconiosis. He attributed claimant’s disease to the presence of talc in the air at claimant’s place of employment resulting from sanding of body filler plastic. He said, however, other chemicals may be involved as well.
Dr. John Tuhy, a specialist in respiratory diseases, testified on behalf of the employer. He examined claimant on one occasion. He also found claimant to be asymptomatic with no breathing difficulties. He examined claimant’s x-rays dating back to 1959 and concluded that claimant’s condition had begun developing as early as 1965. Dr. Tuhy disagreed with Dr. Kazmierski’s diagnosis and indicated that he felt claimant was suffering from sarcoidosis. He ruled out talc pneumoconiosis because a person with that disease suffers shortness of breath, coughing, striking x-ray changes and poor breathing tests, none of which was present in this case. Dr. Tuhy did note, however, that he might agree with Dr. Kazmierski if there was evidence that claimant ingested substantial quantities of talc.
The only evidence of talc present in claimant’s work environment was the affidavits of an employe of claimant’s attorney’s office who contacted representatives of firms making body filler plastic. These representatives stated that talc comprised 50 to 60 percent of their products. Even assuming that this evidence was admissible, there is still no evidence that claimant was exposed to sufficient quantities of talc dust to cause the disease. In fact, contrary to claimant’s testimony, two co-workers testified that the painters were not involved in sanding down the body filler. This function was performed in the body shop. Claimant’s doctor did not point to other specific chemical agents that might cause the condition, and Dr. Tuhy indicated that he knew of no cases where auto spray painters contracted respiratory diseases associated with their work.
*25We agree with the Board that claimant has not met his burden of proving by a preponderance of the evidence that his condition is causally related to his occupation or environment and, therefore, the claim was properly denied.
Affirmed.
ORS 656.802(l)(a) provides:
"(1) As used in ORS 656.802 to 656.824, 'occupational disease’ means:
"(a) Any disease or infection which arises out of and in the scope of the employment, and to which an employe is not ordinarily subjected or exposed other than during a period of regular actual employment therein.”