Multiple chemical sensitivity (MCS) is a chronic recurrent condition characterized by reduced tolerance to various environmental agents or to a class of chemical substances. An evidence-based diagnostic panel is not available nor is there a universally accepted definition of the syndrome. This study retrospectively evaluated the prevalence of MCS symptoms and associated risk factors in a sample of 660 young adults, by means of a structured questionnaire. Symptoms of MCS were found to be widely distributed in the sample population and several of the main risk factors suspected to be associated with MCS were not consistently associated with these symptoms in the sample. On the other hand a significant correlation (p<0.05) was found between atopy and symptoms. Further studies are therefore needed to evaluate this association and reach a unifying definition of the syndrome.