Exposure to different sources of second-hand smoke during pregnancy and its effect on urinary cotinine and tobacco-specific nitrosamine (NNAL) concentrations
Constantine I Vardavas, Eleni Fthenou, Evridiki Patelarou, Emmanouil Bagkeris, Sharon Murphy, Stephen S Hecht, Gregory N Connolly, Leda Chatzi, Manolis Kogevinas
Tobacco Control May 2013, 22 (3) 194-200; DOI: 10.1136/tobaccocontrol-2011-050144