Unless you've been on a desert island, you have probably heard of a relatively new and growing type of occupational disease claim: multiple chemical sensitivity (MCS). Other terms used to describe the same proposed syndrome include 20th Century Disease Syndrome, Immune System Dysregulation or Dysfunction, Total Allergy Syndrome, and even Chemically Acquired Immunodeficiency Syndrome.
The story of MCS goes back to at least the 1950s when a Chicago physician, Theron Randolph, proposed the theory that individuals could be adversely affected by extremely low-level chemical exposures in their environment. He attributed a whole range of symptoms, many of which are typical of everyday experience, to individual susceptibility to such chemicals. Various treatments including rotational diets were proposed, but no controlled, well-structured scientific studies were able to document the condition or efficacy of the unusual therapeutic approaches. The work of Randolph has been highly criticized by the academic community as lacking a scientific basis.
Despite the early skepticism and criticism, the theories of Randolph gained many followers, and the range of interest of these practitioners was significantly enlarged. For example, the "yeast theory" or theory of systemic infection with the common yeast organism Candida Albicans was proposed as a basis for the symptoms of MCS. Authoritative bodies including the American Academy of Allergy and Immunology have cautioned that the theory lacks proof, but it continues to be used as the basis for MCS diagnosis and treatment.
Interest in MCS has grown significantly during the past decade. Many legitimate efforts are being made to determine whether the syndrome actually exists and what may cause it. In the meantime, though, some practitioners have come to wholeheartedly embrace the existence of MCS. These practitioners have developed active MCS practices all over the country, but especially on the West Coast, and in Texas and New York. These practitioners often employ rather unconventional and sometimes quite bizarre forms of treatment for their patients.
Recently, the legal community's interest in this disorder has grown as a small but highly vocal group of health care professionals expound their theories before workers' compensation boards and in courtrooms across the country. Many workers' comp claims and toxic tort actions have resulted from the controversial practices of MCS proponents, who often use the term "clinical ecology" to describe their methods of diagnosis and treatment. These claims initially met with a certain amount of success, but now, many judges have precluded MCS experts and their theories from the courtroom and juries have begun returning verdicts in favor of the defense, sending a clear signal of disbelief, or at least skepticism, in MCS.
The question of MCS prompted a number of occupational physicians and other health care professionals to examine the basis of MCS and undertake studies on patients presenting MCS-type symptoms. Case definitions of the disorder have been developed and it appears that there may be several different variations of MCS.
What Is MCS?
The basic (and unproven) theory of MCS is that chemical exposure can "sensitize" certain individuals to react to that chemical or a huge number of other chemicals and products found throughout the environment. The concept has even been extended to include exposure to electromagnetic fields (EMFs). MCS proponents propose that low-level exposures can initiate this process and that once "sensitized," exceedingly small exposures can trigger symptoms. These exposures are all well below any levels shown heretofore to produce symptoms in either humans or animals. This theory runs counter to the accepted toxicological principle of dose-response. More importantly, this theory goes against one of the tenants of immunology, that if a substance acts as an allergen, a specific antigen-antibody ("lock and key") relationship develops. …