1. U.S. Environmental Protection Agency, National Exposure Research Laboratory, Cincinnati, OH 45268. Correspondence to: 7715 Mitchell Park Dr., Cleves, OH 45002.
2. RAPTOR, Inc., 1586 Covered Bridge Rd., Cincinnati, OH 45231
3. U.S. Environmental Protection Agency, National Exposure Research Laboratory, Cincinnati, OH 45268
4. 9016 Winthrop, Cincinnati, OH 45249