Document 8R6Mb72aL7r8Qg9LE1552XDLa

October 27j 1976 Hr. Mel Birch Younger Laboratories 123 Cliff Cave Road St. Louis, Missouri 631^* Dear MeJLi Please initiate the final feeding phase of the following tissue residue accumulation/depletion studies: Y-7&-266 MCS 1558 trichlorodiphenylmethane Y-75-267 MCS 1560 dichlorodipheny1methane Y-75-268 MCS 1826 chlorodiphenyltnethane These studies will be performed in accordance with the procedures enclosed, with animals to be sacrificed at the Indicated times. Tissue samples will go to Oreille Hicks for analysis. Analyses of tissues from the pilot feedings in these studies indicate that levels of 50 and 500 ppa in the diet should be used In the final feeding phase of the studies. Sincerely, /bkp enc. cc: W.C. Hammann 0. Hicks (enc.) M.V. Stevens, PhD Senior Toxicologist ___ ---------- / Jlf DSW 297726 STLCOPCB4067637