IARC (International Agency for Research on Cancer) have published a report which sets out their priorities for publishing monographs on cancer risks from workplace exposures to various agents. The report can be found at http://monographs.iarc.fr/ENG/Publications/internrep/14-002.pdf .
The report lists more than 50 recommended agents and exposures. The list includes some old favourites (e.g. pesticides, styrene, welding fumes, metal working fluids, methanol, ethyl acrylate and talc), some new ones (e.g. multi-walled carbon nanotubes) and some more general lifestyle and dietary agents at work (e.g. coffee, physical inactivity, obesity, job stress, red meat and processed meat, salt, shiftwork).
Looks like plenty of topics to keep occupational hygienists and occupational health specialists busy over the next few years!