... BROPHY, a, b,cMARGARET M. KEITH, a, b,cKEVIN M. GOREY,cISAAC LUGINAAH,dETHAN LAUKKANEN,eDEBORAH HELLYER, a ABRAHAM REINHARTZ, a ANDREW WATTERSON,bHAKAMABU-ZAHRA,fELEANOR MATICKA-TYNDALE,cKENNETHSCHNEIDER,fMATTHIAS ... National Occupational Classi-fication. Ottawa, Canada.16. STATISTICS CANADA. 1998. North American Industrial Classification System. Ot-tawa, Canada.17. CHECKOWAY, H., N. PEARCE &D.CRAWFORD-BROWN. ... to induce breast cancer in experimental mammals exist in high concentrations in occupational set-tings.11 In spite of the continuing increase in the incidence of cancer in Canada and the existence...