ABSTRACT
NationalToxicologyProgram,NationalInstituteofEnvironmental HealthSciences,ResearchTrianglePark,NorthCarolina
I.INTRODUCTION
I.INTRODUCTION Chemicalscausecancer(quoderatdemonstrandum).Fortunately,
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mostdonot.Certainchemicalscausecancerinhumans[1,2,16,31]; andcertainchemicalscausecancerinanimals[5,13,21,30].Allchemicalsknowntoinducecancerinhumanscausecancerinlaboratoryanimals(apossibleexceptionisarsenic;yetIvankovicetal.[17]diagnosedlungcarcinomasinBDratsafterasingleintratrachealexposure toanarsenic-containingmixtureusedformerlyinvineyards).Therefore,reducingexposuretochemicalsknownorsuspectedtocausecancerinhumansoranimalswillreducechemicallyinducedcancerin humans.Thispublichealthstanceofpreventiveoncologystandsas oneoftheprimarygoalsoftheNationalToxicologyProgram(NTP): toidentifywithcertaintythosechemicalsmostlikelytobehazardous
*Presentaffiliation:EnvironmentalProtectionAgency,Washington, D.C.
