The MCS syndrome (multiple chemical sensitivity syndrome) has been described and commented on by numerous authors as a new type of syndrome caused by environmental factors. It is assumed that the affected individuals react with multiple recurrent and exacerbated symptoms of various organ systems to widely differing types of chemical stimuli in very low concentrations which would not cause any reaction in the general population. Due to the lack of measurable and reproducible effects on health, it has not been possible to define causal relationships. There are no specific physical test results or laboratory markers. However, an understanding of MCS is important for the toxicological evaluation of the risk of chemicals in the low dose range. Although the number of MCS-sufferers who consult doctors of various disciplines is increasing, there is neither a generally accepted clinical definition of this syndrome nor a concurrent conception of its pathogenesis and pathophysiology, and thus there is no agreement in terms of the required therapy. In addition to toxicological factors causing MCS-syndrome, there are many and various other factors which could play a part, but which have not been sufficiently considered in attempts at definition to date [45, 46, 47]. In the literature to MCS syndrome there are numerous publications which make vague attempts to define MCS syndrome on the basis of a traditional medical conception of disease. The situation of the MCS-sufferer shows that the diagnosis of "environmental medical syndromes" is not exclusively the concern of specialists in environmental medicine or even of the non-medical professions, but requires the intensive co-operation of various medical disciplines. The psychological (partial) aetiology of MCS syndrome, which has been frequently observed, does not relieve the attending doctor of the obligation to investigate whether there are toxic, allergological or immunological causes for the organic complaints with which the patient presents.
