“…Duration of employment was used to assess exposure in most of these studies Bertazzi et al, 1982Bertazzi et al, , 1987Nicholson & Selikoff, 1987;De Guire et al, 1988;Taylor et al, 1988;Liss, 1989;Petruska & Engelhard, 1991;Tynes et al, 1994;Yassi et al, 1994Yassi et al, , 2003Savitz & Loomis, 1995;Tironi et al, 1996;Kimbrough et al, 1999Kimbrough et al, , 2003Loomis et al, 1997;Mallin et al, 2004;Prince et al, 2006a, b;Ruder et al, 2006;Ahrens et al, 2007;Hopf et al, 2009bHopf et al, , 2010Hopf et al, , 2014Pesatori et al, 2013). In the remaining studies, exposure to PCBs was assessed using a variety of approaches, including job-exposure matrices (JEM), development of worker's exposure zones, and measurement of serum PCB concentrations.…”