H AZ LETON LA BO RA TO RI ES A M ERI CA , I N C. 9 2 0 0 Leesburg Turnpi ke Vienna , Virginia 22180 U .S.A .

' f: DEPARTMENT OF HEALTH.

June 21, 1973 Mr.

Juso 15| 1970 Mr.

AMERICAN OCCUPATIONAL MEDICAL ASSOCIATION 150 NORTH WACKER DRIVE CHICAGO, ILLINOIS 60606 OSHA ISSUES FINAL LEAD STANDARD REDUCING PERMISSIBLE LEVEL TO 50 ug/ m3 A final st andard for occupat ional exposure t o lead which reduces t he permissible exposure level from 200 t o 50 ug/ m3, based on an 8-hour t ime-weight ed average concent rat ion, was promulgat ed by t he Occupat ional Saf et y and Healt h Administ rat ion on November 14.

,July 3 1970 Mr.

ETHYL CORPORATION Medical Dapartmsnt 451 Florida Baton Rouga, Louisiana 70301 February 5, 1975 TELEPHONE: Area 504 387-0131 Mr.

April 22, 1970 Mr.

V4V ****x#Ttfu// tu#/ ** ^9.19^ d epa r t m en t o f en v ir o n m en t a l h ea l t h Ket t erin g Lab o rat o ry, CofJege of M ed icin e, Ed en & Bet hesd a A ves.

Aprii 7, 1971 J, Julian Chisolm, Jr., M.B.

August 20, 1975 Mr.

HOFFMANN-LA ROCHE INC.

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ESTABLISHED 1802 E.

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