Following similar events in other European countries, some cases of dermatitis related to contact with China-imported furniture possibly treated with dimethyl(E)-butenedioate (dimethylfumarate [DMF]) were reported to the French institute for public health surveillance at the beginning of September 2008. An active multisource case collection was conducted in order to provide an epidemiological description of this outbreak. Results of this investigation show that, in France, mainly during the 4th quarter of 2008, a large number of people presented dermatological symptoms at least plausibly due to a contact with DMF-treated consumer products. The products involved were mostly shoes and sofa (94% of cases). This work offers an example of a multipartner investigation in the field of environmental health. It also shows how the results obtained contributed to decision-making and resulted in the limitation of DMF-treated products in France and in Europe.