This regulation extends the time-limited tolerance for residues of the herbicide pyrithiobac sodium salt (sodium 2-chloro-6- [(4,6-dimethoxypyrimidin-2-yl)thio]benzoate) in or on cottonseed at 0.02 parts per million (ppm). E.I. du Pont de Nemours and Co., Inc., requested this tolerance under the Federal Food, Drug, and Cosmetic Act, as amended by the Food Quality Protection Act of 1966. The tolerance will expire on September 30, 2001.