Jeanne Briskin's March 27, 1989, memo to Gary McKee, Deputy Director, EMSL, requested that information be provided, which would answer several questions concerning the preservation of drinking water samples for lead analysis. It was decided to: Do a literature search for relevant information. Two papers were found. One (Issaq and Zielinski, Loss of Lead from Aqueous Solutions During Storage, Analytical Chemistry, Vol. 46, No. 9, pg. 1328, August 1974) identified the problem of rapid loss of lead into the walls of Pyrex, Kimax and polyethylene sample containers. It concluded that the problem could be alleviated by the use of hydrogen peroxide, which seems to function by preventing adsorption, or nitric acid, which causes resolubilization of adsorbed lead. The second paper (Miller, et. al., Influence of the Time of Acidification after Sample Collection on the Preservation of Drinking Water for Lead Determination, Anal. Chem., Vol. 57, No. 6, pg 1020, May 1985) established that 90% of the lead in a sample is recovered from polyethylene containers if the sample is acidified with nitric acid within 14 days of collection, and the sample is analyzed 'within a day' after acidification.