Document baDL3p5LmDQjmoXNnmvKE589O

w\ D E P A R T M E N T OF 1ED 1CI N E V I SI ON O F I N D U S T R 1AL H Y G I E N E UNIVERSITY. OF COLORADO SC HO O L OF MEDICINE AND 'HOSPITALS 4 2 0 0 E AST NINTH AVE. DENVER, COLO. September 24, 1941 Dr. Robert A. Kehoe Kettering Laboratory University of Cincinnati Cincinnati, Ohio Ky dear Dr. Kehoe: The Division of Industrial Hygiene has been considering a new method for collecting urine samples for lead determinations in a plant where men are exposed to lead fumes. A place suitable for collecting spot samples is not available, and setting up such a space would involve con siderable expense. The management and employees consider the procedure of delivering clean, sterile bottles to workers* homes and then collecting the bottles with urine a few days later as very troublesome and involving danger of contamination or careless handling. We have considered collect ing only the morning urine sample. This specimen would be concentrated, and the Worker would be least likely to contaminate' the sample from dirty clothes or carelessly-washed hands. The worker could void directly into a container prepared in our laboratory and opened only by him and us. We have also considered a procedure similar to that used by Barnes at Westing house where the time elapsed between two urinations is noted and concentra tion expressed as gamma per hour (Journal of Industrial lygiene 21, 464, 1939). The collecting of such a sample vail be done off working premisesT Tie realize that there is no clear relationship between urinary volume aid lead output and that total lead output per 24 hours varies from day to day. However, does the lead output per 8 or 12 hours remain nearly constant? The work of Barnes would seem to indicate that the lead output does remain constant. The question boils down to: Vihat is the diurnal output of lead not in terms of concentration but in terms of total lead excreted? What has been your experience with the total amount1 of lead ex creted in seme portion of the 24 hour period as compared with the total that is excreted in 24 hours? If we get a morning urine sample voided after 8 hours of uninterrupted sleep and containing 10 gamma of lead, would we be justified in thinking that the excretion for the 24 hour day was approximate ly 30 gamma? ') I would appreciate any comments or criticism you can offer. LP :ce ILeota Pekrul N 6196