1. a Cypress Environmental Laboratory, PO 1431, Wichita Falls, TX 76307, USA
2. b Philadelphia Water Department, Bureau of Laboratory Services, 3427 Decatur St, Philadelphia, PA 19136, USA
3. c Texas State University, 601 University Drive, San Marcos, TX 78666, USA
4. d Stantec, Stantec, 500-4515 Central Blvd, Burnaby, BC, V5H 0C6 Canada
5. e School of Public Health, University of California, Room 61-295 CHS, Charles E. Young Drive, South, Box 951772, Los Angeles, CA 90095, USA