[1] Univ Washington, Dept Med, Seattle, WA 98195 USA
[2] Univ Washington, Dept Environm & Occupat Hlth Sci, Seattle, WA 98195 USA
[3] Safety & Hlth Assessment & Res Prevent SHARP Progr, Washington State Dept Lab & Ind, Olympia, WA 98501 USA
[4] Virginia Mason Franciscan Occupat Med Associates, Tacoma, WA 98003 USA
[5] SHARP Program, Washington State Dept Lab & Ind, POB 44330, Olympia, WA 98504 USA