Document 10yM3XOjRRy7qkz3oDg6Y1d75

DEPARTMENT OF HEALTH. EDUCATION. ANO WELFARE pueue health scevics *4rioAfc esarc* m* UM* Mia iaeur4fc aCJLTM Htaa*oaT aaaaaaTi, owo uat April 3, 196? Mr. J. M. Barnhart Executive Secretary National Insulation Manufacturers Association, lac, 441 Lexington Avenue New York, New York 10017 Beet Mr. Barnhart: We have given your letter of February 13, 1967, aad tba material previously seat ua, consldErablE study. As Indicated la tba numerous reprints aad other aatarial you forwardad, a fraat daal of work baa baaa devoted to dafiainf tba biological activity of fibrous (lass. Wa wars laprasaad with tba excellent work raportad la aaay of tba articles. Aay ooa raaaarcb rsport, bowavar, raprasantsd a liaitad seopa of activity, so that tba various reports did aot hava a elosa tie-ia reflecting tba axparlaace of groups of workars la tba ladustry. Wa ballsve a primary weakness la tba knowledge now availabla oo tba bealtb affects of exposure to fibrous glass Is tbs lack of detailed epidemiologic information whereia exposures la tba work aaTiroomaat and tba haaltb patterns of tba workars are correlated so that a quaatitative ralatlo&sblp oaa be established between exposure levels aad a health profile of tba group under study. A broadly-based epidemiologic study of this nature la tba fibrous glass industry would provide vary useful information to supplement research of tba past aad provide answers for the aaay questions now arising which tba peat raaaarcb did aot do. Sincerely yours. Lewis J. Crnllsy, Sefeatfstdlrector Olraotor of Epidemiology aad Field Studies Occupational Health Program