Does formaldehyde cause nasopharyngeal cancer in man?

Formaldehyde is a widely used industrial chemical, which also has uses in consumer products, and hence large numbers of people are exposed to it. It is also an endogenous metabolite with measurable levels in body fluids and tissues. The reports of its carcinogenicity to rats have raised concern about its potential to cause a carcinogenic response in exposed populations. This letter reviews the information on the carcinogenicity of formaldehyde, particularly to the upper respiratory tract, in animals and man.